From Talk Radio News: Reusable Spacecraft Key For Human Space Exploration
SpaceX Founder and CEO Elon Musk addressed a small audience at the National Press Club Thursday to offer his expertise on the future of human space flight exploration.
In the attempt to make the human race a multi-planetary species, Musk said SpaceX has created some of the world’s most reliable and economical launch vehicles and spacecraft. Some, including the Falcon 9 rocket and the Dragon, have gained high global recognition for abilities such as carrying payloads to space at 30-50 percent of the cost of its competitors.
“The pivotal breakthrough that’s necessary, that some company has to come up with to make life multi-planetary, is a fully and rapidly reusable forward-class rocket,” Musk said. The Dragon, he said, fits this description.
The Dragon is SpaceX’s fully reusable spacecraft and is set to launch to the International Space Station on November 3. During that mission the company will be monitoring the reusability for future launches. However, Musk said the company is aware of the various engineering problems, such as spacecraft weight accuracy and engine efficiency.
“If your rocket ends up being just a little bit heavier, you get nothing to orbit,” he said. However, he said, this is a risk the company is willing to take to create for the future of human space flight.
“SpaceX is going to try to do it. We could fail; I’m not saying we have certain success here but we are gonna try to do it,” Musk said.
Musk said SpaceX has been working hard in creating a reusable spacecraft and said it is the key to dramatic cost savings enabling innovative U.S. space exploration programs.
Elon Musk is also the co-founder of Paypal, which he sold to Ebay in 2002 for $1.5 billion which allowed him to start SpaceX.
Friday, September 30, 2011
China’s space station: A new era of space exploration?
From SmartPlanet.com: China’s space station: A new era of space exploration?
With the retirement of NASA’s space shuttles and Russia announcing plans to eventually sink the International Space Station, 2011 hasn’t exactly shaped up to be a banner year for space exploration. But don’t tell that to China, where the feeling is far from mutual.
On Thursday evening, the unmanned Tiangong-1 space lab launched into orbit aboard a Chinese Long March 2F rocket, a monumental milestone for an ascending superpower embarking on it’s own golden age of space exploration. The move is part of the China National Space Administration’s bold vision to put into operation a 60-ton space station in orbit by 2020. In the next phase, officials will launch in 2013 the Tiangong-2, a module equipped to provide three astronauts with a livable environment for about 20 days. Tiangong-3, scheduled for 2015, will enable to the astronauts to stay on-board for about twice as long, during which time they’ll conduct experiments to test regenerative life-support technology and other space survival projects.
* Related: China to launch lunar rover, mine moon for nuclear fuel
While flipping the lights on aboard a fully-functional space station would be an impressive accomplishment for a nation that only eight years ago sent their first astronauts into space, officials would still consider it merely a stepping stone towards much more ambitious goals, such as colonizing the moon and, perhaps, even a manned mission to Mars. But before the fledgling space program can even begin dreaming about setting foot on other planets, scientists need to show that they’re up to task technologically. At this point, it means demonstrating that their Shenzhou space capsule is capable of successfully docking the space lab.
“It’s a big deal at several levels,” said Dean Cheng, a research fellow at the conservative Heritage Foundation told Space.com. “If all goes according to plan this will be China’s initial effort at docking, and of course docking is one of those sin qua nons for more prolonged exploration of space. They have to get this skill set down.”
China is gearing up the Shenzhou spacecraft for three upcoming flights in which it will connect with the Tiangong 1 module. First up is the Shenzhou 8 mission, scheduled to launch in November, followed by Shenzhou 9 the following year. Both trips will be unmanned missions and serve as docking trials in preparation for Shenzhou 10, a potentially manned journey that’s expected to be notable in more than one way since it may include the country’s first female astronaut.
Though the Chinese have completed three manned missions using the capsule, it has never met the type of stringent standards that would have enabled it to dock with the International Space Station. The Space Review’s Dwayne A. Day sheds some light on the often-complicated relations between the U.S. and china and why NASA considers the Shenzhou technology to be unproven:
For starters, the United States has limited knowledge of and therefore no confidence in the Chinese manned spacecraft. To date, Shenzhou has flown only twice with humans aboard. The second flight took place two years after the first, and the third, scheduled for this year, will be three years after the second. It is doubtful that the Chinese themselves can have much understanding and confidence in the vehicle considering how rarely they actually fly it. If they were moving any slower, they’d be going backward. Each new flight accomplishes more than the last, but they may be losing experience they have gained—you can climb stairs with less steps if take them three at a time, but you also run the risk of falling and breaking your neck.
Despite such doubts, China has shown it has no qualms about going its own way and the successful launch of Tiangong-1 should set the stage for what will be — at the very least — a defining year.
Tuesday, September 27, 2011
The planet Venus: A brief history of our knowledge of the planet
Studies
Early studies
The Venus tablet of Ammisaduqa, dated 1581 BC, records the observations of Babylonian astrologers. It refers to Venus as Nin-dar-an-na, or "bright queen of the sky".Venus was known to ancient civilizations both as the "morning star" and as the "evening star", names that reflect the early understanding that these were two separate objects. The Venus tablet of Ammisaduqa, dated 1581 BC, shows that the Babylonians understood that the two were a single object, referred to in the tablet as the "bright queen of the sky," and could support this view with detailed observations.
The Greeks thought of the two as separate stars, Phosphorus and Hesperus, until the time of Pythagoras in the sixth century BC. The Romans designated the morning aspect of Venus as Lucifer, literally "Light-Bringer", and the evening aspect as Vesper.
The transit of Venus was first observed in 1032 by the Persian astronomer Avicenna, who concluded that Venus is closer to the Earth than the Sun, and established that Venus was, at least sometimes, below the Sun. In the 12th century, the Andalusian astronomer Ibn Bajjah observed "two planets as black spots on the face of the Sun," which was later identified as the transit of Venus and Mercury by the Maragha astronomer Qotb al-Din Shirazi in the 13th century.
17th Century
When the Italian physicist Galileo Galilei first observed the planet in the early 17th century, he found that it showed phases like the Moon, varying from crescent to gibbous to full and vice versa. When Venus is furthest from the Sun in the sky it shows a half-lit phase and when it is closest to the Sun in the sky it shows as a crescent or full phase. This could be possible only if Venus orbited the Sun, and this was among the first observations to clearly contradict the Ptolemaic geocentric model that the Solar System was concentric and centered on the Earth.
The atmosphere of Venus was discovered in 1761 by Russian polymath Mikhail Lomonosov. Venus' atmosphere was observed in 1790 by German astronomer Johann Schröter. Schröter found that when the planet was a thin crescent, the cusps extended through more than 180°. He correctly surmised that this was due to scattering of sunlight in a dense atmosphere. Later, American astronomer Chester Smith Lyman observed a complete ring around the dark side of the planet when it was at inferior conjunction, providing further evidence for an atmosphere.
The atmosphere complicated efforts to determine a rotation period for the planet, and observers such as Italian-born astronomer Giovanni Cassini and Schröter incorrectly estimated periods of about 24 hours from the motions of markings on the planet's apparent surface.
Ground-based research
Little more was discovered about Venus until the 20th century. Its almost featureless disc gave no hint what its surface might be like, and it was only with the development of spectroscopic, radar and ultraviolet observations that more of its secrets were revealed. The first UV observations were carried out in the 1920s, when Frank E. Ross found that UV photographs revealed considerable detail that was absent in visible and infrared radiation. He suggested that this was due to a very dense yellow lower atmosphere with high cirrus clouds above it.
Spectroscopic observations in the 1900s gave the first clues about the Venusian rotation. Vesto Slipher tried to measure the Doppler shift of light from Venus, but found that he could not detect any rotation. He surmised that the planet must have a much longer rotation period than had previously been thought. Later work in the 1950s showed that the rotation was retrograde. Radar observations of Venus were first carried out in the 1960s, and provided the first measurements of the rotation period which were close to the modern value.
Radar observations in the 1970s revealed details of the Venusian surface for the first time. Pulses of radio waves were beamed at the planet using the 300 m radio telescope at Arecibo Observatory, and the echoes revealed two highly reflective regions, designated the Alpha and Beta regions. The observations also revealed a bright region attributed to mountains, which was called Maxwell Montes. These three features are now the only ones on Venus which do not have female names.
Exploration
Early efforts
Mariner 2, launched in 1962The first robotic space probe mission to Venus, and the first to any planet, began on February 12, 1961 with the launch of the Venera 1 probe. The first craft of the otherwise highly successful Soviet Venera program, Venera 1 was launched on a direct impact trajectory, but contact was lost seven days into the mission, when the probe was about 2 million km from Earth. It was estimated to have passed within 100,000 km from Venus in mid-May.
The United States exploration of Venus also started badly with the loss of the Mariner 1 probe on launch. The subsequent Mariner 2 mission enjoyed greater success, and after a 109-day transfer orbit on December 14, 1962 it became the world's first successful interplanetary mission, passing 34,833 km above the surface of Venus. Its microwave and infrared radiometers revealed that while the Venusian cloud tops were cool, the surface was extremely hot—at least 425 °C, finally ending any hopes that the planet might harbor ground-based life. Mariner 2 also obtained improved estimates of its mass and of the astronomical unit, but was unable to detect either a magnetic field or radiation belts.
Atmospheric entry
The Soviet Venera 3 probe crash-landed on Venus on March 1, 1966. It was the first man-made object to enter the atmosphere and strike the surface of another planet, though its communication system failed before it was able to return any planetary data.
Venus's next encounter with an unmanned probe came on October 18, 1967 when Venera 4 successfully entered the atmosphere and deployed a number of science experiments. Venera 4 showed that the surface temperature was even hotter than Mariner 2 had measured at almost 500 °C, and that the atmosphere was about 90 to 95% carbon dioxide. The Venusian atmosphere was considerably denser than Venera 4's designers had anticipated, and its slower than intended parachute descent meant that its batteries ran down before the probe reached the surface. After returning descent data for 93 minutes, Venera 4's last pressure reading was 18 bar at an altitude of 24.96 km.[90]
Another probe arrived at Venus one day later on October 19, 1967 when Mariner 5 conducted a flyby at a distance of less than 4000 km above the cloud tops. Mariner 5 was originally built as backup for the Mars-bound Mariner 4, but when that mission was successful, the probe was refitted for a Venus mission. A suite of instruments more sensitive than those on Mariner 2, in particular its radio occultation experiment, returned data on the composition, pressure and density of the Venusian atmosphere.
The joint Venera 4–Mariner 5 data were analyzed by a combined Soviet-American science team in a series of colloquia over the following year, in an early example of space cooperation.[93]
Armed with the lessons and data learned from Venera 4, the Soviet Union launched the twin probes Venera 5 and Venera 6 five days apart in January 1969; they encountered Venus a day apart on May 16 and May 17 that year. The probes were strengthened to improve their crush depth to 25 bar and were equipped with smaller parachutes to achieve a faster descent. Since then-current atmospheric models of Venus suggested a surface pressure of between 75 and 100 bar, neither was expected to survive to the surface. After returning atmospheric data for a little over fifty minutes, they both were crushed at altitudes of approximately 20 km before going on to strike the surface on the night side of Venus.
Surface and atmospheric science
Venera 7 represented an effort to return data from the planet's surface, and was constructed with a reinforced descent module capable of withstanding a pressure of 180 bar. The module was pre-cooled before entry and equipped with a specially reefed parachute for a rapid 35-minute descent.
Entering the atmosphere on December 15, 1970, the parachute is believed to have partially torn during the descent, and the probe struck the surface with a hard, yet not fatal, impact. Probably tilted onto its side, it returned a weak signal supplying temperature data for 23 minutes, the first telemetry received from the surface of another planet.
The Venera program continued with Venera 8 sending data from the surface for 50 minutes, after entering the atmosphere on July 22, 1972. Venera 9, which entered the atmosphere of Venus on October 22, 1975, and Venera 10, which entered the atmosphere three days later on October 25, sent the first images of the Venusian landscape.
The two landing sites presented very different terrain in the immediate vicinities of the landers: Venera 9 had landed on a 20 degree slope scattered with boulders around 30–40 cm across; Venera 10 showed basalt-like rock slabs interspersed with weathered material.
In the meantime, the United States had sent the Mariner 10 probe on a gravitational slingshot trajectory past Venus on its way to Mercury. On February 5, 1974, Mariner 10 passed within 5790 km of Venus, returning over 4000 photographs as it did so. The images, the best then achieved, showed the planet to be almost featureless in visible light, but ultraviolet light revealed details in the clouds that had never been seen in Earth-bound observations.
The American Pioneer Venus project consisted of two separate missions. The Pioneer Venus Orbiter was inserted into an elliptical orbit around Venus on December 4, 1978, and remained there for over thirteen years studying the atmosphere and mapping the surface with radar. The Pioneer Venus Multiprobe released a total of four probes which entered the atmosphere on December 9, 1978, returning data on its composition, winds and heat fluxes.
Four more Venera lander missions took place over the next four years, with Venera 11 and Venera 12 detecting Venusian electrical storms;[98] and Venera 13 and Venera 14, landing four days apart on March 1 and March 5, 1982, returning the first color photographs of the surface. All four missions deployed parachutes for braking in the upper atmosphere, but released them at altitudes of 50 km, the dense lower atmosphere providing enough friction to allow for an unaided soft landing.
Both Venera 13 and 14 analyzed soil samples with an on-board X-ray fluorescence spectrometer, and attempted to measure the compressibility of the soil with an impact probe.[98] Venera 14, though, had the misfortune to strike its own ejected camera lens cap and its probe failed to contact the soil.
The Venera program came to a close in October 1983 when Venera 15 and Venera 16 were placed in orbit to conduct mapping of the Venusian terrain with synthetic aperture radar.
In 1985 the Soviet Union took advantage of the opportunity to combine missions to Venus and Comet Halley, which passed through the inner Solar System that year. En route to Halley, on June 11 and June 15, 1985 the two spacecraft of the Vega program each dropped a Venera-style probe (of which Vega 1's partially failed) and released a balloon-supported aerobot into the upper atmosphere. The balloons achieved an equilibrium altitude of around 53 km, where pressure and temperature are comparable to those at Earth's surface. They remained operational for around 46 hours, and discovered that the Venusian atmosphere was more turbulent than previously believed, and subject to high winds and powerful convection cells.
Radar mapping
The United States' Magellan probe was launched on May 4, 1989 with a mission to map the surface of Venus with radar. The high-resolution images it obtained during its 4½ years of operation far surpassed all prior maps and were comparable to visible-light photographs of other planets. Magellan imaged over 98% of the Venusian surface by radar and mapped 95% of its gravity field. In 1994, at the end of its mission, Magellan was deliberately sent to its destruction into the atmosphere of Venus to quantify its density.[103] Venus was observed by the Galileo and Cassini spacecraft during flybys on their respective missions to the outer planets, but Magellan would otherwise be the last dedicated mission to Venus for over a decade.
Current and future missions
NASA's MESSENGER mission to Mercury performed two flybys of Venus in October 2006 and June 2007, to slow its trajectory for an eventual orbital insertion of Mercury in March 2011. MESSENGER collected scientific data on both those flybys.[106]
The Venus Express probe was designed and built by the European Space Agency. Launched on November 9, 2005 by a Russian Soyuz-Fregat rocket procured through Starsem, it successfully assumed a polar orbit around Venus on April 11, 2006.
The probe is undertaking a detailed study of the Venusian atmosphere and clouds, including mapping of the planet's plasma environment and surface characteristics, particularly temperatures. One of the first results emerging from Venus Express is the discovery that a huge double atmospheric vortex exists at the south pole of the planet.
The Japan Aerospace Exploration Agency (JAXA) devised a Venus orbiter, Akatsuki (formerly "Planet-C"), which was launched on May 20, 2010 but the craft failed to enter orbit in December 2010. Hopes remain that the probe can successfully hibernate and make another insertion attempt in six years. Planned investigations included surface imaging with an infrared camera and experiments designed to confirm the presence of lightning as well as the determination of the existence of current surface volcanism.
The European Space Agency (ESA) hopes to launch a mission to Mercury in 2014, called BepiColombo, which will perform two flybys of Venus before it reaches Mercury orbit in 2020.
Under its New Frontiers Program, NASA has proposed a lander mission called the Venus In-Situ Explorer to land on Venus to study surface conditions and investigate the elemental and mineralogical features of the regolith. The probe would be equipped with a core sampler to drill into the surface and study pristine rock samples not weathered by the very harsh surface conditions. The Venera-D probe is a proposed Russian space probe to Venus, to be launched around 2016 with its goal to make remote-sensing observations around the planet Venus and deploying a lander, based on the Venera design, capable of surviving for a long duration on the planet's surface. Other proposed Venus exploration concepts include rovers, balloons, and airplanes.
NASA has recommended the Surface and Atmosphere Geochemical Explorer (SAGE) candidate mission to land on Venus, with a possible launch in 2016.
Manned flyby
A manned Venus flyby mission, using Apollo program hardware, was proposed in the late 1960s. The mission was planned to launch in late October or early November 1973, and would have used a Saturn V to send three men to fly past Venus in a flight lasting approximately one year. The spacecraft would have passed approximately 5,000 kilometres from the surface of Venus about four months later.
Early studies
The Venus tablet of Ammisaduqa, dated 1581 BC, records the observations of Babylonian astrologers. It refers to Venus as Nin-dar-an-na, or "bright queen of the sky".Venus was known to ancient civilizations both as the "morning star" and as the "evening star", names that reflect the early understanding that these were two separate objects. The Venus tablet of Ammisaduqa, dated 1581 BC, shows that the Babylonians understood that the two were a single object, referred to in the tablet as the "bright queen of the sky," and could support this view with detailed observations.
The Greeks thought of the two as separate stars, Phosphorus and Hesperus, until the time of Pythagoras in the sixth century BC. The Romans designated the morning aspect of Venus as Lucifer, literally "Light-Bringer", and the evening aspect as Vesper.
The transit of Venus was first observed in 1032 by the Persian astronomer Avicenna, who concluded that Venus is closer to the Earth than the Sun, and established that Venus was, at least sometimes, below the Sun. In the 12th century, the Andalusian astronomer Ibn Bajjah observed "two planets as black spots on the face of the Sun," which was later identified as the transit of Venus and Mercury by the Maragha astronomer Qotb al-Din Shirazi in the 13th century.
17th Century
When the Italian physicist Galileo Galilei first observed the planet in the early 17th century, he found that it showed phases like the Moon, varying from crescent to gibbous to full and vice versa. When Venus is furthest from the Sun in the sky it shows a half-lit phase and when it is closest to the Sun in the sky it shows as a crescent or full phase. This could be possible only if Venus orbited the Sun, and this was among the first observations to clearly contradict the Ptolemaic geocentric model that the Solar System was concentric and centered on the Earth.
The atmosphere of Venus was discovered in 1761 by Russian polymath Mikhail Lomonosov. Venus' atmosphere was observed in 1790 by German astronomer Johann Schröter. Schröter found that when the planet was a thin crescent, the cusps extended through more than 180°. He correctly surmised that this was due to scattering of sunlight in a dense atmosphere. Later, American astronomer Chester Smith Lyman observed a complete ring around the dark side of the planet when it was at inferior conjunction, providing further evidence for an atmosphere.
The atmosphere complicated efforts to determine a rotation period for the planet, and observers such as Italian-born astronomer Giovanni Cassini and Schröter incorrectly estimated periods of about 24 hours from the motions of markings on the planet's apparent surface.
Ground-based research
Little more was discovered about Venus until the 20th century. Its almost featureless disc gave no hint what its surface might be like, and it was only with the development of spectroscopic, radar and ultraviolet observations that more of its secrets were revealed. The first UV observations were carried out in the 1920s, when Frank E. Ross found that UV photographs revealed considerable detail that was absent in visible and infrared radiation. He suggested that this was due to a very dense yellow lower atmosphere with high cirrus clouds above it.
Spectroscopic observations in the 1900s gave the first clues about the Venusian rotation. Vesto Slipher tried to measure the Doppler shift of light from Venus, but found that he could not detect any rotation. He surmised that the planet must have a much longer rotation period than had previously been thought. Later work in the 1950s showed that the rotation was retrograde. Radar observations of Venus were first carried out in the 1960s, and provided the first measurements of the rotation period which were close to the modern value.
Radar observations in the 1970s revealed details of the Venusian surface for the first time. Pulses of radio waves were beamed at the planet using the 300 m radio telescope at Arecibo Observatory, and the echoes revealed two highly reflective regions, designated the Alpha and Beta regions. The observations also revealed a bright region attributed to mountains, which was called Maxwell Montes. These three features are now the only ones on Venus which do not have female names.
Exploration
Early efforts
Mariner 2, launched in 1962The first robotic space probe mission to Venus, and the first to any planet, began on February 12, 1961 with the launch of the Venera 1 probe. The first craft of the otherwise highly successful Soviet Venera program, Venera 1 was launched on a direct impact trajectory, but contact was lost seven days into the mission, when the probe was about 2 million km from Earth. It was estimated to have passed within 100,000 km from Venus in mid-May.
The United States exploration of Venus also started badly with the loss of the Mariner 1 probe on launch. The subsequent Mariner 2 mission enjoyed greater success, and after a 109-day transfer orbit on December 14, 1962 it became the world's first successful interplanetary mission, passing 34,833 km above the surface of Venus. Its microwave and infrared radiometers revealed that while the Venusian cloud tops were cool, the surface was extremely hot—at least 425 °C, finally ending any hopes that the planet might harbor ground-based life. Mariner 2 also obtained improved estimates of its mass and of the astronomical unit, but was unable to detect either a magnetic field or radiation belts.
Atmospheric entry
The Soviet Venera 3 probe crash-landed on Venus on March 1, 1966. It was the first man-made object to enter the atmosphere and strike the surface of another planet, though its communication system failed before it was able to return any planetary data.
Venus's next encounter with an unmanned probe came on October 18, 1967 when Venera 4 successfully entered the atmosphere and deployed a number of science experiments. Venera 4 showed that the surface temperature was even hotter than Mariner 2 had measured at almost 500 °C, and that the atmosphere was about 90 to 95% carbon dioxide. The Venusian atmosphere was considerably denser than Venera 4's designers had anticipated, and its slower than intended parachute descent meant that its batteries ran down before the probe reached the surface. After returning descent data for 93 minutes, Venera 4's last pressure reading was 18 bar at an altitude of 24.96 km.[90]
Another probe arrived at Venus one day later on October 19, 1967 when Mariner 5 conducted a flyby at a distance of less than 4000 km above the cloud tops. Mariner 5 was originally built as backup for the Mars-bound Mariner 4, but when that mission was successful, the probe was refitted for a Venus mission. A suite of instruments more sensitive than those on Mariner 2, in particular its radio occultation experiment, returned data on the composition, pressure and density of the Venusian atmosphere.
The joint Venera 4–Mariner 5 data were analyzed by a combined Soviet-American science team in a series of colloquia over the following year, in an early example of space cooperation.[93]
Armed with the lessons and data learned from Venera 4, the Soviet Union launched the twin probes Venera 5 and Venera 6 five days apart in January 1969; they encountered Venus a day apart on May 16 and May 17 that year. The probes were strengthened to improve their crush depth to 25 bar and were equipped with smaller parachutes to achieve a faster descent. Since then-current atmospheric models of Venus suggested a surface pressure of between 75 and 100 bar, neither was expected to survive to the surface. After returning atmospheric data for a little over fifty minutes, they both were crushed at altitudes of approximately 20 km before going on to strike the surface on the night side of Venus.
Surface and atmospheric science
Venera 7 represented an effort to return data from the planet's surface, and was constructed with a reinforced descent module capable of withstanding a pressure of 180 bar. The module was pre-cooled before entry and equipped with a specially reefed parachute for a rapid 35-minute descent.
Entering the atmosphere on December 15, 1970, the parachute is believed to have partially torn during the descent, and the probe struck the surface with a hard, yet not fatal, impact. Probably tilted onto its side, it returned a weak signal supplying temperature data for 23 minutes, the first telemetry received from the surface of another planet.
The Venera program continued with Venera 8 sending data from the surface for 50 minutes, after entering the atmosphere on July 22, 1972. Venera 9, which entered the atmosphere of Venus on October 22, 1975, and Venera 10, which entered the atmosphere three days later on October 25, sent the first images of the Venusian landscape.
The two landing sites presented very different terrain in the immediate vicinities of the landers: Venera 9 had landed on a 20 degree slope scattered with boulders around 30–40 cm across; Venera 10 showed basalt-like rock slabs interspersed with weathered material.
In the meantime, the United States had sent the Mariner 10 probe on a gravitational slingshot trajectory past Venus on its way to Mercury. On February 5, 1974, Mariner 10 passed within 5790 km of Venus, returning over 4000 photographs as it did so. The images, the best then achieved, showed the planet to be almost featureless in visible light, but ultraviolet light revealed details in the clouds that had never been seen in Earth-bound observations.
The American Pioneer Venus project consisted of two separate missions. The Pioneer Venus Orbiter was inserted into an elliptical orbit around Venus on December 4, 1978, and remained there for over thirteen years studying the atmosphere and mapping the surface with radar. The Pioneer Venus Multiprobe released a total of four probes which entered the atmosphere on December 9, 1978, returning data on its composition, winds and heat fluxes.
Four more Venera lander missions took place over the next four years, with Venera 11 and Venera 12 detecting Venusian electrical storms;[98] and Venera 13 and Venera 14, landing four days apart on March 1 and March 5, 1982, returning the first color photographs of the surface. All four missions deployed parachutes for braking in the upper atmosphere, but released them at altitudes of 50 km, the dense lower atmosphere providing enough friction to allow for an unaided soft landing.
Both Venera 13 and 14 analyzed soil samples with an on-board X-ray fluorescence spectrometer, and attempted to measure the compressibility of the soil with an impact probe.[98] Venera 14, though, had the misfortune to strike its own ejected camera lens cap and its probe failed to contact the soil.
The Venera program came to a close in October 1983 when Venera 15 and Venera 16 were placed in orbit to conduct mapping of the Venusian terrain with synthetic aperture radar.
In 1985 the Soviet Union took advantage of the opportunity to combine missions to Venus and Comet Halley, which passed through the inner Solar System that year. En route to Halley, on June 11 and June 15, 1985 the two spacecraft of the Vega program each dropped a Venera-style probe (of which Vega 1's partially failed) and released a balloon-supported aerobot into the upper atmosphere. The balloons achieved an equilibrium altitude of around 53 km, where pressure and temperature are comparable to those at Earth's surface. They remained operational for around 46 hours, and discovered that the Venusian atmosphere was more turbulent than previously believed, and subject to high winds and powerful convection cells.
Radar mapping
The United States' Magellan probe was launched on May 4, 1989 with a mission to map the surface of Venus with radar. The high-resolution images it obtained during its 4½ years of operation far surpassed all prior maps and were comparable to visible-light photographs of other planets. Magellan imaged over 98% of the Venusian surface by radar and mapped 95% of its gravity field. In 1994, at the end of its mission, Magellan was deliberately sent to its destruction into the atmosphere of Venus to quantify its density.[103] Venus was observed by the Galileo and Cassini spacecraft during flybys on their respective missions to the outer planets, but Magellan would otherwise be the last dedicated mission to Venus for over a decade.
Current and future missions
NASA's MESSENGER mission to Mercury performed two flybys of Venus in October 2006 and June 2007, to slow its trajectory for an eventual orbital insertion of Mercury in March 2011. MESSENGER collected scientific data on both those flybys.[106]
The Venus Express probe was designed and built by the European Space Agency. Launched on November 9, 2005 by a Russian Soyuz-Fregat rocket procured through Starsem, it successfully assumed a polar orbit around Venus on April 11, 2006.
The probe is undertaking a detailed study of the Venusian atmosphere and clouds, including mapping of the planet's plasma environment and surface characteristics, particularly temperatures. One of the first results emerging from Venus Express is the discovery that a huge double atmospheric vortex exists at the south pole of the planet.
The Japan Aerospace Exploration Agency (JAXA) devised a Venus orbiter, Akatsuki (formerly "Planet-C"), which was launched on May 20, 2010 but the craft failed to enter orbit in December 2010. Hopes remain that the probe can successfully hibernate and make another insertion attempt in six years. Planned investigations included surface imaging with an infrared camera and experiments designed to confirm the presence of lightning as well as the determination of the existence of current surface volcanism.
The European Space Agency (ESA) hopes to launch a mission to Mercury in 2014, called BepiColombo, which will perform two flybys of Venus before it reaches Mercury orbit in 2020.
Under its New Frontiers Program, NASA has proposed a lander mission called the Venus In-Situ Explorer to land on Venus to study surface conditions and investigate the elemental and mineralogical features of the regolith. The probe would be equipped with a core sampler to drill into the surface and study pristine rock samples not weathered by the very harsh surface conditions. The Venera-D probe is a proposed Russian space probe to Venus, to be launched around 2016 with its goal to make remote-sensing observations around the planet Venus and deploying a lander, based on the Venera design, capable of surviving for a long duration on the planet's surface. Other proposed Venus exploration concepts include rovers, balloons, and airplanes.
NASA has recommended the Surface and Atmosphere Geochemical Explorer (SAGE) candidate mission to land on Venus, with a possible launch in 2016.
Manned flyby
A manned Venus flyby mission, using Apollo program hardware, was proposed in the late 1960s. The mission was planned to launch in late October or early November 1973, and would have used a Saturn V to send three men to fly past Venus in a flight lasting approximately one year. The spacecraft would have passed approximately 5,000 kilometres from the surface of Venus about four months later.
Neil Armstrong says US space program 'embarrassing'
From Google News: Neil Armstrong says US space program 'embarrassing'
WASHINGTON — Neil Armstrong, the first man to walk on the moon, told lawmakers Thursday that the end of the space shuttle era has left the American human spaceflight program in an "embarrassing" state.
"We will have no American access to, and return from, low Earth orbit and the International Space Station for an unpredictable length of time in the future," Armstrong told the House Committee on Science, Space, and Technology.
"For a country that has invested so much for so long to achieve a leadership position in space exploration and exploitation, this condition is viewed by many as lamentably embarrassing and unacceptable."
Armstrong was part of a four-member panel of space experts who told lawmakers that NASA needs a stronger vision for the future and should focus on returning humans to the Moon and to the International Space Station.
"A lead, however earnestly and expensively won, once lost, is nearly impossible to regain," said the US astronaut, now 81, who was commander of Apollo 11 and walked on the Moon in 1969.
President Barack Obama canceled the Constellation program that would have returned humans to the Moon and called on NASA to instead focus on new, deep-space capabilities to carry people to an asteroid by 2025 and Mars by 2030.
The retirement in July of the three-decade-old space shuttle program brought an end to the US capability to send humans to space until private industry can come up with a new commercial space capsule to the ISS, maybe by 2015.
In the meantime, Russia's Soyuz capsules are the only taxis for the world's astronauts heading to low-Earth orbit, and a ticket to the ISS costs global space agencies between 50 and 60 million dollars each.
"Get the shuttle out of the garage down there at Kennedy (Space Center), crank up the motors and put it back in service," said Eugene Cernan, who commanded the Apollo 17 flight and was the last man to walk on the Moon in 1972.
"You want a launch vehicle today that will service the ISS? We've got it sitting down there. So before we put it in a museum, let's make use of it. It's in the prime of its life, how could we just put it away?"
Cernan hailed the vision of John F. Kennedy, "a bold and courageous president who started us on a journey to the stars," and said thousands of Americans have been inspired by the space race with the Soviet Union.
"Today, we are on a path of decay. We are seeing the book close on five decades of accomplishment as the leader in human space exploration," Cernan said.
Cernan said Constellation has been replaced by a "mission to nowhere" and called on NASA to make plans to return to the Moon.
"As unimaginable as it seems, we have now come full circle and ceded our leadership role in space back to the same country -- albeit by a different name -- that spurred our challenge five decades ago."
He added: "I take no solace in the failure of the last Soyuz booster."
Due to technical problem with a Soyuz rocket in August, a Russian cargo ship failed to reach orbit and crashed back to Earth, prompting Russia to temporarily ground a part of its Soyuz program to do emergency checks.
Armstrong and others on the panel appeared to favor the unveiling earlier this month of a massive new launcher capable of powering manned space flights well beyond low-Earth orbit, the Space Launch System, which NASA called the most powerful rocket since the Saturn V rocket put US astronauts on the moon.
Maria Zuber, principal investigator on NASA's unmanned GRAIL (Gravity Recovery and Interior Laboratory) mission that launched earlier this month to orbit the Moon, said lunar study is valuable, but noted that her students are inspired by the notion of exploring Mars.
"The goal of human exploration of Mars is also the consensus opinion of the next generation who will carry out this challenge," she said.
"Unfortunately Congress is cutting back NASA's advanced technology work and it is not clear how the agency will be able to unfold new advanced missions without a more concentrated effort to develop new technologies.
Michael Griffin, professor of mechanical and aerospace engineering at the University of Alabama in Huntsville, raised concerns about a new space race and called China, which wants to put a robot on the Moon in 2013 and build its own space station for 2015, "a near-peer competitor."
"When the Chinese can reach the Moon and we cannot, I do not see why any other nation would regard us as a world leader," he said.
WASHINGTON — Neil Armstrong, the first man to walk on the moon, told lawmakers Thursday that the end of the space shuttle era has left the American human spaceflight program in an "embarrassing" state.
"We will have no American access to, and return from, low Earth orbit and the International Space Station for an unpredictable length of time in the future," Armstrong told the House Committee on Science, Space, and Technology.
"For a country that has invested so much for so long to achieve a leadership position in space exploration and exploitation, this condition is viewed by many as lamentably embarrassing and unacceptable."
Armstrong was part of a four-member panel of space experts who told lawmakers that NASA needs a stronger vision for the future and should focus on returning humans to the Moon and to the International Space Station.
"A lead, however earnestly and expensively won, once lost, is nearly impossible to regain," said the US astronaut, now 81, who was commander of Apollo 11 and walked on the Moon in 1969.
President Barack Obama canceled the Constellation program that would have returned humans to the Moon and called on NASA to instead focus on new, deep-space capabilities to carry people to an asteroid by 2025 and Mars by 2030.
The retirement in July of the three-decade-old space shuttle program brought an end to the US capability to send humans to space until private industry can come up with a new commercial space capsule to the ISS, maybe by 2015.
In the meantime, Russia's Soyuz capsules are the only taxis for the world's astronauts heading to low-Earth orbit, and a ticket to the ISS costs global space agencies between 50 and 60 million dollars each.
"Get the shuttle out of the garage down there at Kennedy (Space Center), crank up the motors and put it back in service," said Eugene Cernan, who commanded the Apollo 17 flight and was the last man to walk on the Moon in 1972.
"You want a launch vehicle today that will service the ISS? We've got it sitting down there. So before we put it in a museum, let's make use of it. It's in the prime of its life, how could we just put it away?"
Cernan hailed the vision of John F. Kennedy, "a bold and courageous president who started us on a journey to the stars," and said thousands of Americans have been inspired by the space race with the Soviet Union.
"Today, we are on a path of decay. We are seeing the book close on five decades of accomplishment as the leader in human space exploration," Cernan said.
Cernan said Constellation has been replaced by a "mission to nowhere" and called on NASA to make plans to return to the Moon.
"As unimaginable as it seems, we have now come full circle and ceded our leadership role in space back to the same country -- albeit by a different name -- that spurred our challenge five decades ago."
He added: "I take no solace in the failure of the last Soyuz booster."
Due to technical problem with a Soyuz rocket in August, a Russian cargo ship failed to reach orbit and crashed back to Earth, prompting Russia to temporarily ground a part of its Soyuz program to do emergency checks.
Armstrong and others on the panel appeared to favor the unveiling earlier this month of a massive new launcher capable of powering manned space flights well beyond low-Earth orbit, the Space Launch System, which NASA called the most powerful rocket since the Saturn V rocket put US astronauts on the moon.
Maria Zuber, principal investigator on NASA's unmanned GRAIL (Gravity Recovery and Interior Laboratory) mission that launched earlier this month to orbit the Moon, said lunar study is valuable, but noted that her students are inspired by the notion of exploring Mars.
"The goal of human exploration of Mars is also the consensus opinion of the next generation who will carry out this challenge," she said.
"Unfortunately Congress is cutting back NASA's advanced technology work and it is not clear how the agency will be able to unfold new advanced missions without a more concentrated effort to develop new technologies.
Michael Griffin, professor of mechanical and aerospace engineering at the University of Alabama in Huntsville, raised concerns about a new space race and called China, which wants to put a robot on the Moon in 2013 and build its own space station for 2015, "a near-peer competitor."
"When the Chinese can reach the Moon and we cannot, I do not see why any other nation would regard us as a world leader," he said.
Space technology is still important
From the Stylus, College at Brockport: Space technology is still important
Apollo astronaut and first man on the Moon, Neil Armstrong, stood up in front of congress to express his disgust over the state of NASA's affairs.
Among his bones of contention with lawmakers is the fact President Obama withdrew support for the Constellation Space Exploration program after promising it was a priority over the past few years. In a letter to the president, Armstrong wrote, "Without the skill and experience that actual spacecraft operation provides, the USA is far too likely to be on a long downhill slide to mediocrity."
These are grim words, but then again, Armstrong is just the right man to say them. He and his crew allegedly traveled over 242,000 miles of dead vacuum to land on the Moon without any guarantee they would be able to get back again. If that worked, they would have to make that same trip back and slam into the atmosphere at 36,000 feet per second, protected by a metal can and some ceramics.
The chances that something could go fatally wrong were astoundingly high. However that didn't stop Neil, Buzz Aldrin, and their pilot, Michael Collins to blast off into history.
Now the space shuttle program is dead and there's nothing left to replace it. These men don't want see the dream of space exploration end in a committee. They risked their lives for these advancements and many of their friends died along the way.
Now, I think it's important for me to clarify this point: I do not blame the president for retiring the shuttle program. The first shuttle was flight-tested in 1977, that's two years older than my 1979 Impala. We got over 30 years of service out of the ships, so I can't blame them for taking those tired old horses out to pasture.
What I do lay at the president's feet is that there was no program to replace the aging fleet. By the time Apollo 17 made its trip to the Moon in December of 1972, the Space Shuttle contract had been awarded to contractors who had been working on it for almost a year.
As Atlantis made its final landing last July, I was bothered by how little it seemed to matter to anyone under 40. I imagine the reason I paid any attention to it was due to the fact that my dad raised me to have an enduring fascination of space. Not everyone my age had that.
I think some of it has to do with that fact that we don't have a sense of urgency about space anymore. In the '60s, everyone wanted to see an American on the Moon before the USSR. As this century breaks, no one sees the point.
We're so jaded by the glut of technology at our fingertips, that we forget just how awesome safely travelling to the Moon and back really is.
We have smart phones and videogame consoles in our homes with more power than the reel-to-reel banks that NASA had in the '60s and they took men into space. Meanwhile, we complain that Google Maps routed us through construction.
The prevailing argument for cutting NASA's budget — and dashing hopes for future space exploration against the rocks — is that we have more pressing earthbound matters to deal with. Fair enough, but let me point out the only way we can do anything meaningful in space is to do it as humans — not Americans, Russians or Chinese.
When I went to the Kennedy Space Center in Florida some years ago, the first thing I noticed was you can easily overhear a dozen languages. It struck me then that exploring space is a human endeavor. If we want to move beyond ourselves, we need to stop wallowing in our petty problems here and look to the stars as one.
Apollo astronaut and first man on the Moon, Neil Armstrong, stood up in front of congress to express his disgust over the state of NASA's affairs.
Among his bones of contention with lawmakers is the fact President Obama withdrew support for the Constellation Space Exploration program after promising it was a priority over the past few years. In a letter to the president, Armstrong wrote, "Without the skill and experience that actual spacecraft operation provides, the USA is far too likely to be on a long downhill slide to mediocrity."
These are grim words, but then again, Armstrong is just the right man to say them. He and his crew allegedly traveled over 242,000 miles of dead vacuum to land on the Moon without any guarantee they would be able to get back again. If that worked, they would have to make that same trip back and slam into the atmosphere at 36,000 feet per second, protected by a metal can and some ceramics.
The chances that something could go fatally wrong were astoundingly high. However that didn't stop Neil, Buzz Aldrin, and their pilot, Michael Collins to blast off into history.
Now the space shuttle program is dead and there's nothing left to replace it. These men don't want see the dream of space exploration end in a committee. They risked their lives for these advancements and many of their friends died along the way.
Now, I think it's important for me to clarify this point: I do not blame the president for retiring the shuttle program. The first shuttle was flight-tested in 1977, that's two years older than my 1979 Impala. We got over 30 years of service out of the ships, so I can't blame them for taking those tired old horses out to pasture.
What I do lay at the president's feet is that there was no program to replace the aging fleet. By the time Apollo 17 made its trip to the Moon in December of 1972, the Space Shuttle contract had been awarded to contractors who had been working on it for almost a year.
As Atlantis made its final landing last July, I was bothered by how little it seemed to matter to anyone under 40. I imagine the reason I paid any attention to it was due to the fact that my dad raised me to have an enduring fascination of space. Not everyone my age had that.
I think some of it has to do with that fact that we don't have a sense of urgency about space anymore. In the '60s, everyone wanted to see an American on the Moon before the USSR. As this century breaks, no one sees the point.
We're so jaded by the glut of technology at our fingertips, that we forget just how awesome safely travelling to the Moon and back really is.
We have smart phones and videogame consoles in our homes with more power than the reel-to-reel banks that NASA had in the '60s and they took men into space. Meanwhile, we complain that Google Maps routed us through construction.
The prevailing argument for cutting NASA's budget — and dashing hopes for future space exploration against the rocks — is that we have more pressing earthbound matters to deal with. Fair enough, but let me point out the only way we can do anything meaningful in space is to do it as humans — not Americans, Russians or Chinese.
When I went to the Kennedy Space Center in Florida some years ago, the first thing I noticed was you can easily overhear a dozen languages. It struck me then that exploring space is a human endeavor. If we want to move beyond ourselves, we need to stop wallowing in our petty problems here and look to the stars as one.
Saturday, September 24, 2011
How Can NASA Not Know Where It Landed????
With all the tracking capability everywhere in the world - how can we not know where the wreckage of this satellite landed? At some point it must have made re-entry which should have been trackable, then simple math will tell you where it came down!
From Yahoo News: NASA: 6-ton satellite hits Earth; location unknown
By SETH BORENSTEIN - Associated Press | AP – 16 mins ago
WASHINGTON (AP) — NASA's dead 6-ton satellite plunged to Earth early Saturday, but more than eight hours later, U.S. space officials didn't know just where it hit. They thought the fiery fall was largely over water and the debris probably hurt no one.
The agency did not give a more specific location in a midday update on its website, which also said officials were not aware of any reports of injuries or property damage. Most of the spacecraft was believed to have burned up.
The bus-sized satellite first penetrated Earth's atmosphere somewhere over the Pacific Ocean, according to NASA and the U.S. Air Force's Joint Space Operations Center. But that doesn't necessarily mean it all fell into the sea.
NASA's earlier calculations had predicted that the 20-year-old former climate research satellite would fall over a 500-mile (800-kilometer) swath and could include land.
Because the plummet began over the ocean and given the lack of any reports of people being hit, that "gives us a good feeling that no one was hurt," but officials didn't know for certain, NASA spokesman Steve Cole told The Associated Press.
The two government agencies said the 35-foot (11-meter) satellite fell sometime between 11:23 p.m. EDT Friday (0323 GMT Saturday) and 1:09 a.m. EDT (0509 GMT) Saturday, but with no precise time or location.
There was rampant speculation on the Internet and Twitter, much of it focusing on unconfirmed reports and even video of debris from the Upper Atmosphere Research Satellite over Alberta, Canada.
Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics said the spacecraft entered the atmosphere around 12:15 a.m. EDT (1615 GMT) over the coast of Washington state. He said much of the debris likely fell over the Pacific Ocean, though its trajectory suggests some of it could have fallen over more heavily populated areas in the U.S. and Canada, including Portland, Oregon; Seattle; Calgary, Alberta; and Saskatoon, Saskatchewan.
"Pieces are falling off of this flaming fire ball, and some of it has enough momentum to go hundreds of miles," he said.
Cole said that was possible because the last track for the satellite included Canada, starting north of Seattle and then in a large arc north then south. From there, the track continued through the Atlantic south toward Africa, but it was unlikely the satellite got that far if it started falling over the Pacific.
Cole said NASA was hoping for more details from the Air Force, which was responsible for tracking debris.
But given where the satellite may have fallen, officials may never quite know precisely.
"Most space debris is in the ocean. It'll be hard to confirm," Cole said.
Some 26 pieces of the satellite representing 1,200 pounds (544 kilograms) of heavy metal had been expected to rain down somewhere. The biggest surviving chunk should be no more than 300 pounds (136 kilograms).
UARS is the biggest NASA spacecraft to crash back to Earth, uncontrolled, since the post-Apollo 75-ton Skylab space station and the more than 10-ton Pegasus 2 satellite, both in 1979.
Russia's 135-ton Mir space station slammed through the atmosphere in 2001, but it was a controlled dive into the Pacific.
Before UARS fell, no one had ever been hit by falling space junk and NASA expected that not to change.
NASA put the chances that somebody somewhere on Earth would get hurt at 1-in-3,200. But any one person's odds of being struck were estimated at 1-in-22 trillion, given there are 7 billion people on the planet.
The satellite ran out of fuel and died in 2005. UARS was built and launched before NASA and other nations started new programs that prevent this type of uncontrolled crashes of satellite.
From Yahoo News: NASA: 6-ton satellite hits Earth; location unknown
By SETH BORENSTEIN - Associated Press | AP – 16 mins ago
WASHINGTON (AP) — NASA's dead 6-ton satellite plunged to Earth early Saturday, but more than eight hours later, U.S. space officials didn't know just where it hit. They thought the fiery fall was largely over water and the debris probably hurt no one.
The agency did not give a more specific location in a midday update on its website, which also said officials were not aware of any reports of injuries or property damage. Most of the spacecraft was believed to have burned up.
The bus-sized satellite first penetrated Earth's atmosphere somewhere over the Pacific Ocean, according to NASA and the U.S. Air Force's Joint Space Operations Center. But that doesn't necessarily mean it all fell into the sea.
NASA's earlier calculations had predicted that the 20-year-old former climate research satellite would fall over a 500-mile (800-kilometer) swath and could include land.
Because the plummet began over the ocean and given the lack of any reports of people being hit, that "gives us a good feeling that no one was hurt," but officials didn't know for certain, NASA spokesman Steve Cole told The Associated Press.
The two government agencies said the 35-foot (11-meter) satellite fell sometime between 11:23 p.m. EDT Friday (0323 GMT Saturday) and 1:09 a.m. EDT (0509 GMT) Saturday, but with no precise time or location.
There was rampant speculation on the Internet and Twitter, much of it focusing on unconfirmed reports and even video of debris from the Upper Atmosphere Research Satellite over Alberta, Canada.
Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics said the spacecraft entered the atmosphere around 12:15 a.m. EDT (1615 GMT) over the coast of Washington state. He said much of the debris likely fell over the Pacific Ocean, though its trajectory suggests some of it could have fallen over more heavily populated areas in the U.S. and Canada, including Portland, Oregon; Seattle; Calgary, Alberta; and Saskatoon, Saskatchewan.
"Pieces are falling off of this flaming fire ball, and some of it has enough momentum to go hundreds of miles," he said.
Cole said that was possible because the last track for the satellite included Canada, starting north of Seattle and then in a large arc north then south. From there, the track continued through the Atlantic south toward Africa, but it was unlikely the satellite got that far if it started falling over the Pacific.
Cole said NASA was hoping for more details from the Air Force, which was responsible for tracking debris.
But given where the satellite may have fallen, officials may never quite know precisely.
"Most space debris is in the ocean. It'll be hard to confirm," Cole said.
Some 26 pieces of the satellite representing 1,200 pounds (544 kilograms) of heavy metal had been expected to rain down somewhere. The biggest surviving chunk should be no more than 300 pounds (136 kilograms).
UARS is the biggest NASA spacecraft to crash back to Earth, uncontrolled, since the post-Apollo 75-ton Skylab space station and the more than 10-ton Pegasus 2 satellite, both in 1979.
Russia's 135-ton Mir space station slammed through the atmosphere in 2001, but it was a controlled dive into the Pacific.
Before UARS fell, no one had ever been hit by falling space junk and NASA expected that not to change.
NASA put the chances that somebody somewhere on Earth would get hurt at 1-in-3,200. But any one person's odds of being struck were estimated at 1-in-22 trillion, given there are 7 billion people on the planet.
The satellite ran out of fuel and died in 2005. UARS was built and launched before NASA and other nations started new programs that prevent this type of uncontrolled crashes of satellite.
The planet Mercury: A brief history of its discovery
From Wikipedia
The earliest known recorded observations of Mercury are from the Mul.Apin tablets. These observations were most likely made by an Assyrian astronomer around the 14th century BC.
The cuneiform name used to designate Mercury on the Mul.Apin tablets is transcribed as Udu.Idim.Gu\u4.Ud ("the jumping planet"). Babylonian records of Mercury date back to the 1st millennium BC. The Babylonians called the planet Nabu after the messenger to the gods in their mythology.
The ancient Greeks of Hesiod's time knew the planet as Στίλβων (Stilbon), meaning "the gleaming", and Ἑρμάων (Hermaon). Later Greeks called the planet Apollo when it was visible in the morning sky, and Hermes when visible in the evening. Around the 4th century BC, Greek astronomers came to understand that the two names referred to the same body.
The Romans named the planet after the swift-footed Roman messenger god, Mercury (Latin Mercurius), which they equated with the Greek Hermes, because it moves across the sky faster than any other planet. The Roman-Egyptian astronomer Ptolemy wrote about the possibility of planetary transits across the face of the Sun in his work Planetary Hypotheses. He suggested that no transits had been observed either because planets such as Mercury were too small to see, or because the transits were too infrequent.
In ancient China, Mercury was known as Chen Xing, the Hour Star. It was associated with the direction north and the phase of water in the Wu Xing. Modern Chinese, Korean, Japanese and Vietnamese cultures refer to the planet literally as the “water star”, based on the Five elements.
Hindu mythology used the name Budha for Mercury, and this god was thought to preside over Wednesday. The god Odin (or Woden) of Germanic paganism was associated with the planet Mercury and Wednesday. The Maya may have represented Mercury as an owl (or possibly four owls; two for the morning aspect and two for the evening) that served as a messenger to the underworld.
In ancient Indian astronomy, the Surya Siddhanta, an Indian astronomical text of the 5th century, estimates the diameter of Mercury as 3,008 miles, an error of less than 1% from the currently accepted diameter of 3,032 miles. This estimate was based upon an inaccurate guess of the planet's angular diameter as 3.0 arcminutes.
In medieval Islamic astronomy, the Andalusian astronomer Abū Ishāq Ibrāhīm al-Zarqālī in the 11th century described the deferent of Mercury's geocentric orbit as being oval, like an egg or a pignon, although this insight did not influence his astronomical theory or his astronomical calculations. In the 12th century, Ibn Bajjah observed "two planets as black spots on the face of the Sun," which was later suggested as the transit of Mercury and/or Venus by the Maragha astronomer Qotb al-Din Shirazi in the 13th century. (Note that most such medieval reports of transits were later taken as observations of sunspots.)
In India, the Kerala school astronomer Nilakantha Somayaji in the 15th century developed a partially heliocentric planetary model in which Mercury orbits the Sun, which in turn orbits the Earth, similar to the Tychonic system later proposed by Tycho Brahe in the late 16th century.
Ground-based telescopic research
The first telescopic observations of Mercury were made by Galileo in the early 17th century. Although he observed phases when he looked at Venus, his telescope was not powerful enough to see the phases of Mercury.
In 1631 Pierre Gassendi made the first telescopic observations of the transit of a planet across the Sun when he saw a transit of Mercury predicted by Johannes Kepler. In 1639 Giovanni Zupi used a telescope to discover that the planet had orbital phases similar to Venus and the Moon. The observation demonstrated conclusively that Mercury orbited around the Sun.
A very rare event in astronomy is the passage of one planet in front of another (occultation), as seen from Earth. Mercury and Venus occult each other every few centuries, and the event of May 28, 1737 is the only one historically observed, having been seen by John Bevis at the Royal Greenwich Observatory. The next occultation of Mercury by Venus will be on December 3, 2133.
The difficulties inherent in observing Mercury mean that it has been far less studied than the other planets. In 1800 Johann Schröter made observations of surface features, claiming to have observed 20 km high mountains. Friedrich Bessel used Schröter's drawings to erroneously estimate the rotation period as 24 hours and an axial tilt of 70°. In the 1880s Giovanni Schiaparelli mapped the planet more accurately, and suggested that Mercury’s rotational period was 88 days, the same as its orbital period due to tidal locking.
This phenomenon is known as synchronous rotation and is shown by Earth’s Moon. The effort to map the surface of Mercury was continued by Eugenios Antoniadi, who published a book in 1934 that included both maps and his own observations. Many of the planet's surface features, particularly the albedo features, take their names from Antoniadi's map.
In June 1962 Soviet scientists at the Institute of Radio-engineering and Electronics of the USSR Academy of Sciences led by Vladimir Kotelnikov became first to bounce radar signal off Mercury and receive it, starting radar observations of the planet. Three years later radar observations by Americans Gordon Pettengill and R. Dyce using 300-meter Arecibo Observatory radio telescope in Puerto Rico showed conclusively that the planet’s rotational period was about 59 days.
The theory that Mercury’s rotation was synchronous had become widely held, and it was a surprise to astronomers when these radio observations were announced. If Mercury were tidally locked, its dark face would be extremely cold, but measurements of radio emission revealed that it was much hotter than expected. Astronomers were reluctant to drop the synchronous rotation theory and proposed alternative mechanisms such as powerful heat-distributing winds to explain the observations.
Italian astronomer Giuseppe Colombo noted that the rotation value was about two-thirds of Mercury’s orbital period, and proposed that the planet’s orbital and rotational periods were locked into a 3:2 rather than a 1:1 resonance. Data from Mariner 10 subsequently confirmed this view.
This means that Schiaparelli's and Antoniadi's maps were not "wrong". Instead, the astronomers saw the same features during every second orbit and recorded them, but disregarded those seen in the meantime, when Mercury's other face was toward the Sun, since the orbital geometry meant that these observations were made under poor viewing conditions.
Ground-based optical observations did not shed much further light on the innermost planet, but radio astronomers using interferometery at microwave wavelengths, a technique that enables removal of the solar radiation, were able to discern physical and chemical characteristics of the subsurface layers to a depth of several meters.
Not until the first space probe flew past Mercury did many of its most fundamental morphological properties become known. Moreover, recent technological advances have led to improved ground-based observations. In 2000, high-resolution lucky imaging observations were conducted by the Mount Wilson Observatory 1.5 meter Hale telescope. They provided the first views that resolved surface features on the parts of Mercury which were not imaged in the Mariner mission.
Later imaging has shown evidence of a huge double-ringed impact basin even larger than the Caloris Basin in the non-Mariner-imaged hemisphere. It has informally been dubbed the Skinakas Basin. Most of the planet has been mapped by the Arecibo radar telescope, with 5 km resolution, including polar deposits in shadowed craters of what may be water ice.
Exploration of Mercury
Reaching Mercury from Earth poses significant technical challenges, since the planet orbits so much closer to the Sun than does the Earth. A Mercury-bound spacecraft launched from Earth must travel over 91 million kilometers into the Sun’s gravitational potential well. Mercury has an orbital speed of 48 km/s, while Earth’s orbital speed is 30 km/s. Thus the spacecraft must make a large change in velocity (delta-v) to enter a Hohmann transfer orbit that passes near Mercury, as compared to the delta-v required for other planetary missions.
The potential energy liberated by moving down the Sun’s potential well becomes kinetic energy; requiring another large delta-v change to do anything other than rapidly pass by Mercury. To land safely or enter a stable orbit the spacecraft would rely entirely on rocket motors. Aerobraking is ruled out because the planet has very little atmosphere. A trip to Mercury requires more rocket fuel than that required to escape the Solar System completely. As a result, only two space probes have visited the planet so far. A proposed alternative approach would use a solar sail to attain a Mercury-synchronous orbit around the Sun.
Mariner 10
The first spacecraft to visit Mercury was NASA’s Mariner 10 (1974–75). The spacecraft used the gravity of Venus to adjust its orbital velocity so that it could approach Mercury, making it both the first spacecraft to use this gravitational “slingshot” effect and the first NASA mission to visit multiple planets.
Mariner 10 provided the first close-up images of Mercury’s surface, which immediately showed its heavily cratered nature, and revealed many other types of geological features, such as the giant scarps which were later ascribed to the effect of the planet shrinking slightly as its iron core cools. Unfortunately, due to the length of Mariner 10's orbital period, the same face of the planet was lit at each of Mariner 10’s close approaches. This made observation of both sides of the planet impossible, and resulted in the mapping of less than 45% of the planet’s surface.
On March 27, 1974, two days before its first flyby of Mercury, Mariner 10's instruments began registering large amounts of unexpected ultraviolet radiation near Mercury. This led to the tentative identification of Mercury's moon. Shortly afterward, the source of the excess UV was identified as the star 31 Crateris, and Mercury's moon passed into astronomy's history books as a footnote.
The spacecraft made three close approaches to Mercury, the closest of which took it to within 327 km of the surface. At the first close approach, instruments detected a magnetic field, to the great surprise of planetary geologists—Mercury’s rotation was expected to be much too slow to generate a significant dynamo effect.
The second close approach was primarily used for imaging, but at the third approach, extensive magnetic data were obtained. The data revealed that the planet’s magnetic field is much like the Earth’s, which deflects the solar wind around the planet. The origin of Mercury’s magnetic field is still the subject of several competing theories.
On March 24, 1975, just eight days after its final close approach, Mariner 10 ran out of fuel. Since its orbit could no longer be accurately controlled, mission controllers instructed the probe to shut down.[135] Mariner 10 is thought to be still orbiting the Sun, passing close to Mercury every few months.
MESSENGER
MESSENGER being prepared for launchA second NASA mission to Mercury, named MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging), was launched on August 3, 2004, from the Cape Canaveral Air Force Station aboard a Boeing Delta 2 rocket. It made a fly-by of the Earth in August 2005, and of Venus in October 2006 and June 2007 to place it onto the correct trajectory to reach an orbit around Mercury.
A first fly-by of Mercury occurred on January 14, 2008, a second on October 6, 2008,[138] and a third on September 29, 2009. Most of the hemisphere not imaged by Mariner 10 has been mapped during these fly-bys. The probe successfully entered an elliptical orbit around the planet on March 18, 2011. The first orbital image of Mercury was obtained on March 29, 2011. The nominal mapping mission is one terrestrial year.[138]
The mission is designed to clear up six key issues: Mercury’s high density, its geological history, the nature of its magnetic field, the structure of its core, whether it has ice at its poles, and where its tenuous atmosphere comes from. To this end, the probe is carrying imaging devices which will gather much higher resolution images of much more of the planet than Mariner 10, assorted spectrometers to determine abundances of elements in the crust, and magnetometers and devices to measure velocities of charged particles. Detailed measurements of tiny changes in the probe’s velocity as it orbits will be used to infer details of the planet’s interior structure.
BepiColombo
The European Space Agency is planning a joint mission with Japan called BepiColombo, which will orbit Mercury with two probes: one to map the planet and the other to study its magnetosphere. Once launched, the spacecraft bus is expected to reach Mercury in 2019.
The bus will release a magnetometer probe into an elliptical orbit, then chemical rockets will fire to deposit the mapper probe into a circular orbit. Both probes will operate for a terrestrial year.[140] The mapper probe will carry an array of spectrometers similar to those on MESSENGER, and will study the planet at many different wavelengths including infrared, ultraviolet, X-ray and gamma ray.
The earliest known recorded observations of Mercury are from the Mul.Apin tablets. These observations were most likely made by an Assyrian astronomer around the 14th century BC.
The cuneiform name used to designate Mercury on the Mul.Apin tablets is transcribed as Udu.Idim.Gu\u4.Ud ("the jumping planet"). Babylonian records of Mercury date back to the 1st millennium BC. The Babylonians called the planet Nabu after the messenger to the gods in their mythology.
The ancient Greeks of Hesiod's time knew the planet as Στίλβων (Stilbon), meaning "the gleaming", and Ἑρμάων (Hermaon). Later Greeks called the planet Apollo when it was visible in the morning sky, and Hermes when visible in the evening. Around the 4th century BC, Greek astronomers came to understand that the two names referred to the same body.
The Romans named the planet after the swift-footed Roman messenger god, Mercury (Latin Mercurius), which they equated with the Greek Hermes, because it moves across the sky faster than any other planet. The Roman-Egyptian astronomer Ptolemy wrote about the possibility of planetary transits across the face of the Sun in his work Planetary Hypotheses. He suggested that no transits had been observed either because planets such as Mercury were too small to see, or because the transits were too infrequent.
In ancient China, Mercury was known as Chen Xing, the Hour Star. It was associated with the direction north and the phase of water in the Wu Xing. Modern Chinese, Korean, Japanese and Vietnamese cultures refer to the planet literally as the “water star”, based on the Five elements.
Hindu mythology used the name Budha for Mercury, and this god was thought to preside over Wednesday. The god Odin (or Woden) of Germanic paganism was associated with the planet Mercury and Wednesday. The Maya may have represented Mercury as an owl (or possibly four owls; two for the morning aspect and two for the evening) that served as a messenger to the underworld.
In ancient Indian astronomy, the Surya Siddhanta, an Indian astronomical text of the 5th century, estimates the diameter of Mercury as 3,008 miles, an error of less than 1% from the currently accepted diameter of 3,032 miles. This estimate was based upon an inaccurate guess of the planet's angular diameter as 3.0 arcminutes.
In medieval Islamic astronomy, the Andalusian astronomer Abū Ishāq Ibrāhīm al-Zarqālī in the 11th century described the deferent of Mercury's geocentric orbit as being oval, like an egg or a pignon, although this insight did not influence his astronomical theory or his astronomical calculations. In the 12th century, Ibn Bajjah observed "two planets as black spots on the face of the Sun," which was later suggested as the transit of Mercury and/or Venus by the Maragha astronomer Qotb al-Din Shirazi in the 13th century. (Note that most such medieval reports of transits were later taken as observations of sunspots.)
In India, the Kerala school astronomer Nilakantha Somayaji in the 15th century developed a partially heliocentric planetary model in which Mercury orbits the Sun, which in turn orbits the Earth, similar to the Tychonic system later proposed by Tycho Brahe in the late 16th century.
Ground-based telescopic research
The first telescopic observations of Mercury were made by Galileo in the early 17th century. Although he observed phases when he looked at Venus, his telescope was not powerful enough to see the phases of Mercury.
In 1631 Pierre Gassendi made the first telescopic observations of the transit of a planet across the Sun when he saw a transit of Mercury predicted by Johannes Kepler. In 1639 Giovanni Zupi used a telescope to discover that the planet had orbital phases similar to Venus and the Moon. The observation demonstrated conclusively that Mercury orbited around the Sun.
A very rare event in astronomy is the passage of one planet in front of another (occultation), as seen from Earth. Mercury and Venus occult each other every few centuries, and the event of May 28, 1737 is the only one historically observed, having been seen by John Bevis at the Royal Greenwich Observatory. The next occultation of Mercury by Venus will be on December 3, 2133.
The difficulties inherent in observing Mercury mean that it has been far less studied than the other planets. In 1800 Johann Schröter made observations of surface features, claiming to have observed 20 km high mountains. Friedrich Bessel used Schröter's drawings to erroneously estimate the rotation period as 24 hours and an axial tilt of 70°. In the 1880s Giovanni Schiaparelli mapped the planet more accurately, and suggested that Mercury’s rotational period was 88 days, the same as its orbital period due to tidal locking.
This phenomenon is known as synchronous rotation and is shown by Earth’s Moon. The effort to map the surface of Mercury was continued by Eugenios Antoniadi, who published a book in 1934 that included both maps and his own observations. Many of the planet's surface features, particularly the albedo features, take their names from Antoniadi's map.
In June 1962 Soviet scientists at the Institute of Radio-engineering and Electronics of the USSR Academy of Sciences led by Vladimir Kotelnikov became first to bounce radar signal off Mercury and receive it, starting radar observations of the planet. Three years later radar observations by Americans Gordon Pettengill and R. Dyce using 300-meter Arecibo Observatory radio telescope in Puerto Rico showed conclusively that the planet’s rotational period was about 59 days.
The theory that Mercury’s rotation was synchronous had become widely held, and it was a surprise to astronomers when these radio observations were announced. If Mercury were tidally locked, its dark face would be extremely cold, but measurements of radio emission revealed that it was much hotter than expected. Astronomers were reluctant to drop the synchronous rotation theory and proposed alternative mechanisms such as powerful heat-distributing winds to explain the observations.
Italian astronomer Giuseppe Colombo noted that the rotation value was about two-thirds of Mercury’s orbital period, and proposed that the planet’s orbital and rotational periods were locked into a 3:2 rather than a 1:1 resonance. Data from Mariner 10 subsequently confirmed this view.
This means that Schiaparelli's and Antoniadi's maps were not "wrong". Instead, the astronomers saw the same features during every second orbit and recorded them, but disregarded those seen in the meantime, when Mercury's other face was toward the Sun, since the orbital geometry meant that these observations were made under poor viewing conditions.
Ground-based optical observations did not shed much further light on the innermost planet, but radio astronomers using interferometery at microwave wavelengths, a technique that enables removal of the solar radiation, were able to discern physical and chemical characteristics of the subsurface layers to a depth of several meters.
Not until the first space probe flew past Mercury did many of its most fundamental morphological properties become known. Moreover, recent technological advances have led to improved ground-based observations. In 2000, high-resolution lucky imaging observations were conducted by the Mount Wilson Observatory 1.5 meter Hale telescope. They provided the first views that resolved surface features on the parts of Mercury which were not imaged in the Mariner mission.
Later imaging has shown evidence of a huge double-ringed impact basin even larger than the Caloris Basin in the non-Mariner-imaged hemisphere. It has informally been dubbed the Skinakas Basin. Most of the planet has been mapped by the Arecibo radar telescope, with 5 km resolution, including polar deposits in shadowed craters of what may be water ice.
Exploration of Mercury
Reaching Mercury from Earth poses significant technical challenges, since the planet orbits so much closer to the Sun than does the Earth. A Mercury-bound spacecraft launched from Earth must travel over 91 million kilometers into the Sun’s gravitational potential well. Mercury has an orbital speed of 48 km/s, while Earth’s orbital speed is 30 km/s. Thus the spacecraft must make a large change in velocity (delta-v) to enter a Hohmann transfer orbit that passes near Mercury, as compared to the delta-v required for other planetary missions.
The potential energy liberated by moving down the Sun’s potential well becomes kinetic energy; requiring another large delta-v change to do anything other than rapidly pass by Mercury. To land safely or enter a stable orbit the spacecraft would rely entirely on rocket motors. Aerobraking is ruled out because the planet has very little atmosphere. A trip to Mercury requires more rocket fuel than that required to escape the Solar System completely. As a result, only two space probes have visited the planet so far. A proposed alternative approach would use a solar sail to attain a Mercury-synchronous orbit around the Sun.
Mariner 10
The first spacecraft to visit Mercury was NASA’s Mariner 10 (1974–75). The spacecraft used the gravity of Venus to adjust its orbital velocity so that it could approach Mercury, making it both the first spacecraft to use this gravitational “slingshot” effect and the first NASA mission to visit multiple planets.
Mariner 10 provided the first close-up images of Mercury’s surface, which immediately showed its heavily cratered nature, and revealed many other types of geological features, such as the giant scarps which were later ascribed to the effect of the planet shrinking slightly as its iron core cools. Unfortunately, due to the length of Mariner 10's orbital period, the same face of the planet was lit at each of Mariner 10’s close approaches. This made observation of both sides of the planet impossible, and resulted in the mapping of less than 45% of the planet’s surface.
On March 27, 1974, two days before its first flyby of Mercury, Mariner 10's instruments began registering large amounts of unexpected ultraviolet radiation near Mercury. This led to the tentative identification of Mercury's moon. Shortly afterward, the source of the excess UV was identified as the star 31 Crateris, and Mercury's moon passed into astronomy's history books as a footnote.
The spacecraft made three close approaches to Mercury, the closest of which took it to within 327 km of the surface. At the first close approach, instruments detected a magnetic field, to the great surprise of planetary geologists—Mercury’s rotation was expected to be much too slow to generate a significant dynamo effect.
The second close approach was primarily used for imaging, but at the third approach, extensive magnetic data were obtained. The data revealed that the planet’s magnetic field is much like the Earth’s, which deflects the solar wind around the planet. The origin of Mercury’s magnetic field is still the subject of several competing theories.
On March 24, 1975, just eight days after its final close approach, Mariner 10 ran out of fuel. Since its orbit could no longer be accurately controlled, mission controllers instructed the probe to shut down.[135] Mariner 10 is thought to be still orbiting the Sun, passing close to Mercury every few months.
MESSENGER
MESSENGER being prepared for launchA second NASA mission to Mercury, named MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging), was launched on August 3, 2004, from the Cape Canaveral Air Force Station aboard a Boeing Delta 2 rocket. It made a fly-by of the Earth in August 2005, and of Venus in October 2006 and June 2007 to place it onto the correct trajectory to reach an orbit around Mercury.
A first fly-by of Mercury occurred on January 14, 2008, a second on October 6, 2008,[138] and a third on September 29, 2009. Most of the hemisphere not imaged by Mariner 10 has been mapped during these fly-bys. The probe successfully entered an elliptical orbit around the planet on March 18, 2011. The first orbital image of Mercury was obtained on March 29, 2011. The nominal mapping mission is one terrestrial year.[138]
The mission is designed to clear up six key issues: Mercury’s high density, its geological history, the nature of its magnetic field, the structure of its core, whether it has ice at its poles, and where its tenuous atmosphere comes from. To this end, the probe is carrying imaging devices which will gather much higher resolution images of much more of the planet than Mariner 10, assorted spectrometers to determine abundances of elements in the crust, and magnetometers and devices to measure velocities of charged particles. Detailed measurements of tiny changes in the probe’s velocity as it orbits will be used to infer details of the planet’s interior structure.
BepiColombo
The European Space Agency is planning a joint mission with Japan called BepiColombo, which will orbit Mercury with two probes: one to map the planet and the other to study its magnetosphere. Once launched, the spacecraft bus is expected to reach Mercury in 2019.
The bus will release a magnetometer probe into an elliptical orbit, then chemical rockets will fire to deposit the mapper probe into a circular orbit. Both probes will operate for a terrestrial year.[140] The mapper probe will carry an array of spectrometers similar to those on MESSENGER, and will study the planet at many different wavelengths including infrared, ultraviolet, X-ray and gamma ray.
Friday, September 23, 2011
NASA gives 1-hour window for falling satellit
From Yahoo News: NASA gives 1-hour window for falling satellite
CAPE CANAVERAL, Florida (AP) — A 6-ton NASA satellite on a collision course with Earth clung to space Friday, apparently flipping position in its ever-lower orbit and stalling its death plunge.
The old research spacecraft was targeted to crash through the atmosphere sometime Friday night or early Saturday, putting Canada and Africa in the potential crosshairs, although most of the satellite should burn up during re-entry. The United States wasn't entirely out of the woods; the possible strike zone skirted Washington state.
"It just doesn't want to come down," said Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics.
McDowell said the satellite's delayed demise demonstrates how unreliable predictions can be. That said, "the best guess is that it will still splash in the ocean, just because there's more ocean out there."
Until Friday, increased solar activity was causing the atmosphere to expand and the 35-foot, bus-size satellite to free fall more quickly. But late Friday morning, NASA said the sun was no longer the major factor in the rate of descent and that the satellite's position, shape or both had changed by the time it slipped down to a 100-mile orbit.
"In the last 24 hours, something has happened to the spacecraft," said NASA orbital debris scientist Mark Matney.
On Friday night, NASA said it expected the satellite to come crashing down between 11:45 p.m. and 12:45 a.m. EDT Saturday. It was going to be passing over the Atlantic, Pacific and Indian oceans at that time, as well as Canada and Africa.
"The risk to public safety is very remote," NASA said in a statement.
Any surviving wreckage is expected to be limited to a 500-mile swath.
The Upper Atmosphere Research Satellite, or UARS, will be the biggest NASA spacecraft to crash back to Earth, uncontrolled, since the post-Apollo 75-ton Skylab space station and the more than 10-ton Pegasus 2 satellite, both in 1979.
Russia's 135-ton Mir space station slammed through the atmosphere in 2001, but it was a controlled dive into the Pacific.
Some 26 pieces of the UARS satellite — representing 1,200 pounds of heavy metal — are expected to rain down somewhere. The biggest surviving chunk should be no more than 300 pounds (136 kilograms).
Earthlings can take comfort in the fact that no one has ever been hurt by falling space junk — to anyone's knowledge — and there has been no serious property damage. NASA put the chances that somebody somewhere on Earth would get hurt at 1-in-3,200. But any one person's odds of being struck were estimated at 1-in-22 trillion, given there are 7 billion people on the planet.
"Keep in mind that we have bits of debris re-entering the atmosphere every single day," Matney said in brief remarks broadcast on NASA TV.
In any case, finders definitely aren't keepers.
Any surviving wreckage belongs to NASA, and it is against the law to keep or sell even the smallest piece. There are no toxic chemicals on board, but sharp edges could be dangerous, so the space agency is warning the public to keep hands off and call police.
The $740 million UARS was launched in 1991 from space shuttle Discovery to study the atmosphere and the ozone layer. At the time, the rules weren't as firm for safe satellite disposal; now a spacecraft must be built to burn up upon re-entry or have a motor to propel it into a much higher, long-term orbit.
NASA shut UARS down in 2005 after lowering its orbit to hurry its end. A potential satellite-retrieval mission was ruled out following the 2003 shuttle Columbia disaster, and NASA did not want the satellite hanging around orbit posing a debris hazard.
Space junk is a growing problem in low-Earth orbit. More than 20,000 pieces of debris, at least 4 inches in diameter, are being tracked on a daily basis. These objects pose a serious threat to the International Space Station.
CAPE CANAVERAL, Florida (AP) — A 6-ton NASA satellite on a collision course with Earth clung to space Friday, apparently flipping position in its ever-lower orbit and stalling its death plunge.
The old research spacecraft was targeted to crash through the atmosphere sometime Friday night or early Saturday, putting Canada and Africa in the potential crosshairs, although most of the satellite should burn up during re-entry. The United States wasn't entirely out of the woods; the possible strike zone skirted Washington state.
"It just doesn't want to come down," said Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics.
McDowell said the satellite's delayed demise demonstrates how unreliable predictions can be. That said, "the best guess is that it will still splash in the ocean, just because there's more ocean out there."
Until Friday, increased solar activity was causing the atmosphere to expand and the 35-foot, bus-size satellite to free fall more quickly. But late Friday morning, NASA said the sun was no longer the major factor in the rate of descent and that the satellite's position, shape or both had changed by the time it slipped down to a 100-mile orbit.
"In the last 24 hours, something has happened to the spacecraft," said NASA orbital debris scientist Mark Matney.
On Friday night, NASA said it expected the satellite to come crashing down between 11:45 p.m. and 12:45 a.m. EDT Saturday. It was going to be passing over the Atlantic, Pacific and Indian oceans at that time, as well as Canada and Africa.
"The risk to public safety is very remote," NASA said in a statement.
Any surviving wreckage is expected to be limited to a 500-mile swath.
The Upper Atmosphere Research Satellite, or UARS, will be the biggest NASA spacecraft to crash back to Earth, uncontrolled, since the post-Apollo 75-ton Skylab space station and the more than 10-ton Pegasus 2 satellite, both in 1979.
Russia's 135-ton Mir space station slammed through the atmosphere in 2001, but it was a controlled dive into the Pacific.
Some 26 pieces of the UARS satellite — representing 1,200 pounds of heavy metal — are expected to rain down somewhere. The biggest surviving chunk should be no more than 300 pounds (136 kilograms).
Earthlings can take comfort in the fact that no one has ever been hurt by falling space junk — to anyone's knowledge — and there has been no serious property damage. NASA put the chances that somebody somewhere on Earth would get hurt at 1-in-3,200. But any one person's odds of being struck were estimated at 1-in-22 trillion, given there are 7 billion people on the planet.
"Keep in mind that we have bits of debris re-entering the atmosphere every single day," Matney said in brief remarks broadcast on NASA TV.
In any case, finders definitely aren't keepers.
Any surviving wreckage belongs to NASA, and it is against the law to keep or sell even the smallest piece. There are no toxic chemicals on board, but sharp edges could be dangerous, so the space agency is warning the public to keep hands off and call police.
The $740 million UARS was launched in 1991 from space shuttle Discovery to study the atmosphere and the ozone layer. At the time, the rules weren't as firm for safe satellite disposal; now a spacecraft must be built to burn up upon re-entry or have a motor to propel it into a much higher, long-term orbit.
NASA shut UARS down in 2005 after lowering its orbit to hurry its end. A potential satellite-retrieval mission was ruled out following the 2003 shuttle Columbia disaster, and NASA did not want the satellite hanging around orbit posing a debris hazard.
Space junk is a growing problem in low-Earth orbit. More than 20,000 pieces of debris, at least 4 inches in diameter, are being tracked on a daily basis. These objects pose a serious threat to the International Space Station.
Thursday, September 22, 2011
Storm of Controversy Bedevils NASA's New Deep Space Program
From TechNewsWOrld: Storm of Controversy Bedevils NASA's New Deep Space Program
By Richard Adhikari
TechNewsWorld
NASA has launched a new deep space manned exploration program, but the project is already facing opposition from the White House that may keep it from getting off the ground. At issue is the program's cost. The White House is concerned that the project may cost more than $60 billion through 2025, nearly double the original estimate of $35 billion.
Struggling through a welter of controversy, the U.S. National Aeronautics and Space Administration this week announced plans for a new deep space exploration program.
At the heart of the Space Launch System is development of an advanced heavy-lift launch vehicle that will enable human exploration in space.
The program seeks to develop two vehicles that will carry the Orion Multi-Purpose Crew Vehicle into space, along with cargo, equipment and science experiments, among other things.
"There will be a heavy lifter for cargo and a smaller, safer one for human flight," Rogier Windhorst, a professor in the School of Earth and Space Exploration at Arizona State University (ASU), told TechNewsWorld.
The SLS launch vehicles "will be able to place an unprecedented payload mass into orbit with a single launch," NASA spokesperson J.D. Harrington said. "The anticipated lift capability will allow a significant increase in the ability to perform scientific and human missions."
The SLS program will use a combination of existing and new technologies, Harrington told TechNewsWorld.
However, the project has been surrounded by controversy. The White House is reportedly concerned about the price tag, and an independent analysis found NASA's projections flawed, according to The Wall Street Journal.
Space Cowboys Do It in SLS
Despite its problems with the SLS project, NASA has adopted an upbeat attitude, publishing a document titled "SLS Fun Facts" on its website, for instance.
The document includes statistics about SLS likely to dazzle space aficionados. For example, the initial vehicle will stand 320 feet high, and the SLS Evolved Lift Capability will be 400 feet. The initial vehicle will weigh 5.5 million pounds and have a payload of 70 metric tons, equal to 12 fully grown elephants, while the Evolved Lift Capability will weigh 6.5 million pounds, and have a payload of 130 metric tons, the equivalent of 21 fully grown elephants.
NASA plans to reuse hardware and manufacturing tooling from previous programs to hold down costs.
"The SLS development plan leverages existing Constellation and Shuttle Program and Ares Project derived hardware and manufacturing tooling while incorporating advanced manufacturing processes, new operational efficiencies and a streamlined approach to acquisition and management that we anticipate will lead to savings," NASA's Harrington said.
The New NASA Math
NASA expects the new design "to cost (US)$3 billion per year," agency spokesperson Harrington remarked, adding NASA will "continue to refine cost and schedule estimates on an ongoing basis."
That refinement may be sorely needed.
The White House is concerned that the project may cost more than $60 billion through 2025, nearly double the original estimate of $35 billion, The Wall Street Journal reported.
NASA got Booz Allen Hamilton to conduct an independent assessment to validate its costs, and the results "provided that validation," Harrington said.
That statement stands in stark contrast to the Journal's report, which stated that Booz Allen found some of NASA's projections overly optimistic and that some were based on unjustified, sometimes substantial, assumed future cost savings.
Other Battles
NASA's plan to rely on equipment and materials from previous programs could add to the cost of the SLS program, according to the WSJ article.
Meanwhile, NASA has reportedly delayed providing specific plans to Congress.
Further, a bipartisan group of lawmakers who support NASA's plans have criticized White House officials and subpoenaed thousands of pages of NASA documents, after essentially accusing the Office of Management and Budget of delaying tactics, The Wall Street Journal said.
Then there's the Planetary Society, founded in 1980 by Carl Sagan, Bruce Murray and Louis Friedman to advocate space exploration.
The society blasted the SLS program during testimony before the U.S. House of Representatives' Committee on Science, Space and Technology in July.
SLS is "wasteful" and has no clear mission goals. Also, the SLS rocket won't advance exploration, and NASA can't afford to build or sustain the SLS rockets, the Planetary Society said.
By Richard Adhikari
TechNewsWorld
NASA has launched a new deep space manned exploration program, but the project is already facing opposition from the White House that may keep it from getting off the ground. At issue is the program's cost. The White House is concerned that the project may cost more than $60 billion through 2025, nearly double the original estimate of $35 billion.
Struggling through a welter of controversy, the U.S. National Aeronautics and Space Administration this week announced plans for a new deep space exploration program.
At the heart of the Space Launch System is development of an advanced heavy-lift launch vehicle that will enable human exploration in space.
The program seeks to develop two vehicles that will carry the Orion Multi-Purpose Crew Vehicle into space, along with cargo, equipment and science experiments, among other things.
"There will be a heavy lifter for cargo and a smaller, safer one for human flight," Rogier Windhorst, a professor in the School of Earth and Space Exploration at Arizona State University (ASU), told TechNewsWorld.
The SLS launch vehicles "will be able to place an unprecedented payload mass into orbit with a single launch," NASA spokesperson J.D. Harrington said. "The anticipated lift capability will allow a significant increase in the ability to perform scientific and human missions."
The SLS program will use a combination of existing and new technologies, Harrington told TechNewsWorld.
However, the project has been surrounded by controversy. The White House is reportedly concerned about the price tag, and an independent analysis found NASA's projections flawed, according to The Wall Street Journal.
Space Cowboys Do It in SLS
Despite its problems with the SLS project, NASA has adopted an upbeat attitude, publishing a document titled "SLS Fun Facts" on its website, for instance.
The document includes statistics about SLS likely to dazzle space aficionados. For example, the initial vehicle will stand 320 feet high, and the SLS Evolved Lift Capability will be 400 feet. The initial vehicle will weigh 5.5 million pounds and have a payload of 70 metric tons, equal to 12 fully grown elephants, while the Evolved Lift Capability will weigh 6.5 million pounds, and have a payload of 130 metric tons, the equivalent of 21 fully grown elephants.
NASA plans to reuse hardware and manufacturing tooling from previous programs to hold down costs.
"The SLS development plan leverages existing Constellation and Shuttle Program and Ares Project derived hardware and manufacturing tooling while incorporating advanced manufacturing processes, new operational efficiencies and a streamlined approach to acquisition and management that we anticipate will lead to savings," NASA's Harrington said.
The New NASA Math
NASA expects the new design "to cost (US)$3 billion per year," agency spokesperson Harrington remarked, adding NASA will "continue to refine cost and schedule estimates on an ongoing basis."
That refinement may be sorely needed.
The White House is concerned that the project may cost more than $60 billion through 2025, nearly double the original estimate of $35 billion, The Wall Street Journal reported.
NASA got Booz Allen Hamilton to conduct an independent assessment to validate its costs, and the results "provided that validation," Harrington said.
That statement stands in stark contrast to the Journal's report, which stated that Booz Allen found some of NASA's projections overly optimistic and that some were based on unjustified, sometimes substantial, assumed future cost savings.
Other Battles
NASA's plan to rely on equipment and materials from previous programs could add to the cost of the SLS program, according to the WSJ article.
Meanwhile, NASA has reportedly delayed providing specific plans to Congress.
Further, a bipartisan group of lawmakers who support NASA's plans have criticized White House officials and subpoenaed thousands of pages of NASA documents, after essentially accusing the Office of Management and Budget of delaying tactics, The Wall Street Journal said.
Then there's the Planetary Society, founded in 1980 by Carl Sagan, Bruce Murray and Louis Friedman to advocate space exploration.
The society blasted the SLS program during testimony before the U.S. House of Representatives' Committee on Science, Space and Technology in July.
SLS is "wasteful" and has no clear mission goals. Also, the SLS rocket won't advance exploration, and NASA can't afford to build or sustain the SLS rockets, the Planetary Society said.
Villagers’ astronaut son shares passion for space program, plans for the future
The Villages Daily Sun, Dlorida: Villagers’ astronaut son shares passion for space program, plans for the future
By DAISY MOON, DAILY SUN The Villages Daily Sun
THE VILLAGES — Characteristically humble, Andrew Feustel attributes his success as an astronaut to being “in the right place at the right time.”
Dig a little deeper into this space genius’ career and it’s easy to see that the past several years of his life have been about much more than luck.
He’s flown twice into space — first in 2009 as a crew member of space shuttle Atlantis during its STS-125 mission to the Hubble Space Telescope, then again in 2011 as the lead space walker of the STS-134 Endeavour crew during a mission to the International Space Station.
In the months and years surrounding his visits into space, Feustel has been traveling the world, promoting space education to students as he shares insight into his out-of-this-world career.
All the while, his family, including wife Indira and their two sons, have stood by his side offering their emotional support. He’s also had two very important fans rooting him on throughout his space endeavors from right here in The Villages: his father, Steve, and stepmother, Beth.
The Village of Duval residents, who divide their time between Florida and Michigan, were at Kennedy Space Center to witness their son’s inaugural and, later, his final flight into space.
While their son performed his space walks, the pair kept tuned in to NASA television watching Andrew, whom they call Drew, sporting his massive white spacesuit as he made repairs and climbed, hopped and floated about his missions.
“We kind of knew what to expect the second time,” Beth said.
Steve noted that he and his wife remained positive, keeping faith that their son would return to Earth safely.
“I wasn’t really too nervous,” Steve said, reflecting on his son’s two missions. “I knew that the people that were supporting him and the crew were doing everything they could to make them safe.”
“They’ve always been very supportive,” Andrew said of his father and stepmother, sharing his appreciation of their working to “increase awareness in The Villages of the work we’ve done in space flight.”
Andrew has visited The Villages, he said, and plans to return sometime in the future.
Role model
To put it simply, Andrew Feustel is one busy man. Aside from his space travels, which include tedious preparation and often many hours of waiting simply hoping for a clear take-off, Feustel devotes his time to the younger generation.
During his final flight into space, he took aboard a stuffed character named Krtech, which has long been featured in a popular Czechoslovakian children’s television show.
“My wife’s mother is from the Czech Republic,” he shared in a phone interview from Houston, Texas. “We’ve always been interested in the culture there.”
Space flight is something that is very important in the country of his wife’s ancestors, he explained, thus prompting him to further promote the study of space by including Krtech in his final mission.
Through his space endeavors, Andrew aims to serve as a role model for people of every age, a fact his parents frequently pointed out during the times surrounding Andrew’s two space missions.
“I like to think that (astronauts) are role models for people who stay focused on tasks,” he said, noting that those in his field often have “high expectations of ourselves.”
“We want to advance science and technology for the betterment of our lives,” he explained.
The road to NASA
Before he was gaining recognition as an astronaut, Andrew was a student who merely dreamed of what was to come, never imagining the grand adventures that awaited him.
“From an early age, I was interested in space flight and exploration and tried to pursue a career in science and technology,” he said.
After graduating from Purdue University, Andrew earned his Ph.D. from Queens University in Ontario, Canada.
From there, he went on to work as a geophysicist in Houston.
It was while living in Houston that he decided to attempt the road toward becoming an astronaut.
“I saw the opportunity to apply to the space program,” he said. “I think it was about luck and being in the right place at the right time.
“It was a great opportunity,” Andrew added. “And I feel very fortunate to have had the chance to (work for NASA).”
His first couple of years with NASA were spent in basic training, he said. “In my case, learning about the space shuttle systems and space systems.”
In learning how to fly a shuttle, Andrew worked with robotics operations, he said.
He compared an astronaut’s basic-level training to the years spent earning an undergraduate degree in college. It’s during that time that all facets of what an astronaut does are covered, Andrew said.
Then, at last, his chance came to leave Earth for his first trip into outer space.
“It’s a pretty exciting event,” Andrew said of his initial voyage into space. “It’s a wild ride. The big adrenaline rush is when you know the countdown is proceeding down to zero.”
That’s when the realization hit him, he said, that “we were no longer going to be staying on the planet.”
What’s ahead
With the landing of Space Shuttle Atlantis in July came what appears to be the conclusion of NASA’s manned shuttle program.
Steve noted the disappointment such news brings with it.
“The excitement is kind of minimized in that we don’t have a launch to look forward to,” he said.
However the proud dad pointed out that he’s certainly looking forward to the next phase of his son’s NASA career.
“It’s kind of neat to be able to participate and be aware of all the things that he’s been doing,” Steve said.
So what is next for Andrew Feustel? For one, he’ll be paying a visit to Italy to see the pope. Steve plans to look after his grandsons while Andrew and Indira are away.
This won’t be Andrew’s first encounter with Pope Benedict XVI. Steve said that during the STS-134 mission, the pope called the astronauts while they were in space.
And while he won’t be traveling to the International Space Station anytime soon, Andrew’s space exploits aren’t exactly coming to a halt.
“What’s happening here for us (at NASA) is sort of a function of all of the years of the budget challenge,” he explained, “and sort of a decision that we need to move past (the shuttle program) to lower-orbit space flight.”
Thus, NASA’s efforts will now be turned from a longtime consummation of the shuttle program to focusing on lower-orbit flight, he said, noting that “retiring the shuttle will open up new opportunities for all of the (space) industry, and space flight will continue to progress.”
Wednesday, September 21, 2011
$500 million launch platform may find new life
From MSNBC: $500 million launch platform may find new life
A brand-new launch platform built for NASA moon rockets may instead help send people to asteroids or Mars — or a private company could use it to loft astronauts to low-Earth orbit.
NASA completed the $500 million mobile launch platform in 2010 to prepare for the Ares 1 rocket, part of its moon-oriented Constellation program. Though the Obama administration canceled Constellation last year, the platform should still get significant use, NASA officials said.
The U.S. space agency is looking at adapting the structure for its next-generation deep space rocket, which is known as the Space Launch System (SLS). While that may be the platform's most likely fate, the private company Alliant Techsystems (ATK) has also inquired about the structure for its Liberty rocket, a contender to ferry NASA astronauts to the International Space Station.
"We're looking at using it for SLS, and all those possibilities still are being evaluated," NASA spokesman Allard Beutel said.
After Constellation
The mobile launch platform stands about 390 feet (119 meters) tall and is parked at NASA's seaside Kennedy Space Center in Cape Canaveral, Fla.
The platform was built to host the Ares 1 rocket launches that would have lofted the crew-carrying Orion spacecraft skyward under NASA's Constellation program. Constellation aimed to return humans to the moon by 2020; NASA spent about $9 billion over four years on research, technology and infrastructure for the project before it was scrapped.
Engineers craned the final piece of the massive platform into place in January 2010. But a month later, President Barack Obama announced he was canceling Constellation and directing NASA to work instead toward getting astronauts to an asteroid by 2025, then on to Mars by the mid-2030s.
On Sept. 14, NASA announced its plans for SLS, the huge deep space rocket that should help make these long journeys possible. SLS will carry a revised version of the Orion capsule, called the Orion Multi-Purpose Crew Vehicle, and should be ready for its first test flight by the end of 2017, officials said.
When the giant rocket is ready to go, it could well blast off from the mobile launch platform.
"The basic structure of the tower is in place and could support an SLS rocket," Beutel told Space.com in an email. "So, we're looking at the modifications that would be needed to specifically support the SLS and Orion spacecraft, such as the power and propellant umbilicals (pipes, cables, etc.) now that we've announced the SLS architecture."
At NASA's Kennedy Space Center in Florida, NASA's new mobile launcher support structure, consisting of a base, a tower and a launch mount, is complete. It took about two years to build.
While that's what NASA's looking at right now, nothing is set in stone yet, Beutel added. And other parties have expressed interest in using the platform as well.
Private spaceflight possibilities
The Utah-based ATK is working with European firm Astrium to develop a rocket called Liberty. For 30 years, ATK provided the reusable twin solid rocket boosters that launched NASA's space shuttles to low-Earth orbit.
ATK also was tapped to develop the first stage of the Ares 1, and it built a solid rocket motor similar to the shuttle's boosters, but slightly longer. Liberty will incorporate that engine as a first stage and Astrium's Ariane 5 rocket as a second stage, ATK officials have said.
ATK and Astrium hope that NASA selects Liberty to launch its crews to low-Earth orbit. Under its Commercial Crew Development (CCDev) program, the space agency is seeking to spur the capabilities of American private spaceflight companies.
NASA hopes these firms can eventually take over the taxi role of ferrying its astronauts to and from the International Space Station — a service that Russian Soyuz vehicles have been exclusively providing in the wake of the space shuttle fleet's retirement in July. The agency hopes private spacecraft will be ready to go by 2015 or so.
Liberty is slated to stand about 300 feet tall (91 m) — considerably smaller than the SLS, which may be a towering 400 feet (122 m) in its final configuration. But the mobile launch platform could accommodate either rocket at the moment, Beutel said, since the wiring and piping that would make it specific to one launch vehicle haven't been installed yet.
ATK
The new Liberty launch vehicle, which draws on parts of NASA's canceled Ares I rocket and Europe's Ariane 5 rocket, will use existing infrastructure at Kennedy Space Center — including, possibly, the mobile launch platform.
"ATK has expressed interest in using it, and we've discussed it with them," Beutel said.
While NASA has yet to make a final decision about the mobile launcher's fate, the death of Constellation did not consign the massive structure to the scrap heap.
"I can definitely say the mobile launcher has a lot of potential uses beyond Ares 1," Beutel said.
A brand-new launch platform built for NASA moon rockets may instead help send people to asteroids or Mars — or a private company could use it to loft astronauts to low-Earth orbit.
NASA completed the $500 million mobile launch platform in 2010 to prepare for the Ares 1 rocket, part of its moon-oriented Constellation program. Though the Obama administration canceled Constellation last year, the platform should still get significant use, NASA officials said.
The U.S. space agency is looking at adapting the structure for its next-generation deep space rocket, which is known as the Space Launch System (SLS). While that may be the platform's most likely fate, the private company Alliant Techsystems (ATK) has also inquired about the structure for its Liberty rocket, a contender to ferry NASA astronauts to the International Space Station.
"We're looking at using it for SLS, and all those possibilities still are being evaluated," NASA spokesman Allard Beutel said.
After Constellation
The mobile launch platform stands about 390 feet (119 meters) tall and is parked at NASA's seaside Kennedy Space Center in Cape Canaveral, Fla.
The platform was built to host the Ares 1 rocket launches that would have lofted the crew-carrying Orion spacecraft skyward under NASA's Constellation program. Constellation aimed to return humans to the moon by 2020; NASA spent about $9 billion over four years on research, technology and infrastructure for the project before it was scrapped.
Engineers craned the final piece of the massive platform into place in January 2010. But a month later, President Barack Obama announced he was canceling Constellation and directing NASA to work instead toward getting astronauts to an asteroid by 2025, then on to Mars by the mid-2030s.
On Sept. 14, NASA announced its plans for SLS, the huge deep space rocket that should help make these long journeys possible. SLS will carry a revised version of the Orion capsule, called the Orion Multi-Purpose Crew Vehicle, and should be ready for its first test flight by the end of 2017, officials said.
When the giant rocket is ready to go, it could well blast off from the mobile launch platform.
"The basic structure of the tower is in place and could support an SLS rocket," Beutel told Space.com in an email. "So, we're looking at the modifications that would be needed to specifically support the SLS and Orion spacecraft, such as the power and propellant umbilicals (pipes, cables, etc.) now that we've announced the SLS architecture."
At NASA's Kennedy Space Center in Florida, NASA's new mobile launcher support structure, consisting of a base, a tower and a launch mount, is complete. It took about two years to build.
While that's what NASA's looking at right now, nothing is set in stone yet, Beutel added. And other parties have expressed interest in using the platform as well.
Private spaceflight possibilities
The Utah-based ATK is working with European firm Astrium to develop a rocket called Liberty. For 30 years, ATK provided the reusable twin solid rocket boosters that launched NASA's space shuttles to low-Earth orbit.
ATK also was tapped to develop the first stage of the Ares 1, and it built a solid rocket motor similar to the shuttle's boosters, but slightly longer. Liberty will incorporate that engine as a first stage and Astrium's Ariane 5 rocket as a second stage, ATK officials have said.
ATK and Astrium hope that NASA selects Liberty to launch its crews to low-Earth orbit. Under its Commercial Crew Development (CCDev) program, the space agency is seeking to spur the capabilities of American private spaceflight companies.
NASA hopes these firms can eventually take over the taxi role of ferrying its astronauts to and from the International Space Station — a service that Russian Soyuz vehicles have been exclusively providing in the wake of the space shuttle fleet's retirement in July. The agency hopes private spacecraft will be ready to go by 2015 or so.
Liberty is slated to stand about 300 feet tall (91 m) — considerably smaller than the SLS, which may be a towering 400 feet (122 m) in its final configuration. But the mobile launch platform could accommodate either rocket at the moment, Beutel said, since the wiring and piping that would make it specific to one launch vehicle haven't been installed yet.
ATK
The new Liberty launch vehicle, which draws on parts of NASA's canceled Ares I rocket and Europe's Ariane 5 rocket, will use existing infrastructure at Kennedy Space Center — including, possibly, the mobile launch platform.
"ATK has expressed interest in using it, and we've discussed it with them," Beutel said.
While NASA has yet to make a final decision about the mobile launcher's fate, the death of Constellation did not consign the massive structure to the scrap heap.
"I can definitely say the mobile launcher has a lot of potential uses beyond Ares 1," Beutel said.
NASA looks to solar to power engines for space exploration
From Clean Energy.com: NASA looks to solar to power engines for space exploration
The origins of modern photovoltaics can be found in NASA’s powering of satellites. But now the U.S. space exploration agency is looking to photovoltaics to provide propulsion for space exploration. Most recently the agency asked six companies to explore using photovoltaics to power ion-thrust engines for spacecraft undergoing deep-space missions.
NASA has asked Analytical Mechanics Associates Inc., Ball Aerospace & Technologies Corp., The Boeing Co., Lockheed Martin Space Systems Company and Northrop Grumman Systems Corp. to develop plans for deploying solar electric propulsion systems for future spacecraft.
It will award approximately $3 million with a maximum individual contract award of $600,000, the agency said in a press release.
“Each company will provide a final report to help define a mission concept to demonstrate the solar electric propulsion technologies, capabilities, and infrastructure required for sustainable, affordable human presence in space,” NASA said.
Photovoltaics are being considered to power the engines because they can provide electricity for a much longer period than batteries alone. As part of the research NASA asked the companies to pursue, it also asked them to evaluate which photovoltaics will be the most cost effective.
In the past, most satellites have used germanium-based cells because of their high efficiency levels, but other photovoltaics may offer certain advantages over that technology now. For instance, flexible photovoltaics could be folded for deployment but when unfurled could provide a larger collection area for sunlight.
Spacecraft today use liquid or solid rocket fuel as the power source to break through the earth’s gravitational barrier. These fuel sources require a lot of physical space and add a lot of weight to a spacecraft. Ion-based engines use a lot of electricity, but little actual propellant to generate thrust, which means a smaller amount of propellant could fly a craft much farther in space.
However, some spacecraft already are using ion thrusters. Most are geosynchronous satellites with ion-hull thrusters, used to help the satellites remain in the proper position, according to said Kurt Hack, a NASA chief engineer on the solar-electric propulsion demonstration project.
“Because of that, they’re operating at a much lower power,” he said. “They’ll do some short maneuvers to keep them in their position.”
To provide large amounts of electricity, NASA is looking into solar-electric propulsion systems.
“There are really two classes of thrusters we’re looking at the fit the type of missions we’re [considering],” Hack said. The main engine designs they’re considering are Hall effect thrusters and ion engines.
“The basic concept is you ionize the gas and send it through something to accelerate it,” Hack said.
The gas is ionized with large amounts of electricity using magnetic or electrostatic forces.
“The propellant of choice is a dense, yet easily ionizable material, typically using a noble gas,” he said.
According to Hack, Xenon is the most typically used gas in such engines because it is easier to ionize.
The gas is expelled from the engine at incredibly high speeds, averaging around 20 kilometers per second, providing propulsion. For comparison, the speed of sound, depending on atmospheric conditions, is about 1 kilometer per three seconds.
But because of a slow mass flow, such engines use very little fuel.
“The tank size on board will dictate how long [the engines] can run,” said Cameron Cunningham, NASA project manager with the demonstration project.
NASA plans to announce winners over the next month or so and to receive the studies as early as January 2012, he said.
The origins of modern photovoltaics can be found in NASA’s powering of satellites. But now the U.S. space exploration agency is looking to photovoltaics to provide propulsion for space exploration. Most recently the agency asked six companies to explore using photovoltaics to power ion-thrust engines for spacecraft undergoing deep-space missions.
NASA has asked Analytical Mechanics Associates Inc., Ball Aerospace & Technologies Corp., The Boeing Co., Lockheed Martin Space Systems Company and Northrop Grumman Systems Corp. to develop plans for deploying solar electric propulsion systems for future spacecraft.
It will award approximately $3 million with a maximum individual contract award of $600,000, the agency said in a press release.
“Each company will provide a final report to help define a mission concept to demonstrate the solar electric propulsion technologies, capabilities, and infrastructure required for sustainable, affordable human presence in space,” NASA said.
Photovoltaics are being considered to power the engines because they can provide electricity for a much longer period than batteries alone. As part of the research NASA asked the companies to pursue, it also asked them to evaluate which photovoltaics will be the most cost effective.
In the past, most satellites have used germanium-based cells because of their high efficiency levels, but other photovoltaics may offer certain advantages over that technology now. For instance, flexible photovoltaics could be folded for deployment but when unfurled could provide a larger collection area for sunlight.
Spacecraft today use liquid or solid rocket fuel as the power source to break through the earth’s gravitational barrier. These fuel sources require a lot of physical space and add a lot of weight to a spacecraft. Ion-based engines use a lot of electricity, but little actual propellant to generate thrust, which means a smaller amount of propellant could fly a craft much farther in space.
However, some spacecraft already are using ion thrusters. Most are geosynchronous satellites with ion-hull thrusters, used to help the satellites remain in the proper position, according to said Kurt Hack, a NASA chief engineer on the solar-electric propulsion demonstration project.
“Because of that, they’re operating at a much lower power,” he said. “They’ll do some short maneuvers to keep them in their position.”
To provide large amounts of electricity, NASA is looking into solar-electric propulsion systems.
“There are really two classes of thrusters we’re looking at the fit the type of missions we’re [considering],” Hack said. The main engine designs they’re considering are Hall effect thrusters and ion engines.
“The basic concept is you ionize the gas and send it through something to accelerate it,” Hack said.
The gas is ionized with large amounts of electricity using magnetic or electrostatic forces.
“The propellant of choice is a dense, yet easily ionizable material, typically using a noble gas,” he said.
According to Hack, Xenon is the most typically used gas in such engines because it is easier to ionize.
The gas is expelled from the engine at incredibly high speeds, averaging around 20 kilometers per second, providing propulsion. For comparison, the speed of sound, depending on atmospheric conditions, is about 1 kilometer per three seconds.
But because of a slow mass flow, such engines use very little fuel.
“The tank size on board will dictate how long [the engines] can run,” said Cameron Cunningham, NASA project manager with the demonstration project.
NASA plans to announce winners over the next month or so and to receive the studies as early as January 2012, he said.
Sunday, September 18, 2011
The hunt for rocks from space
From BBC News Magazine: The hunt for rocks from space
In a hunt that makes the proverbial needle in a haystack look like easy quarry, scientists have begun the search for remains of a suspected meteor which lit up the skies over the south-western US this week. How do they know where to start looking, and why do they bother?
The meteor, which appeared as a dazzling streak of flame, was probably a chunk of space rock about the size of a football, scientists say.
They believe tiny pieces of the meteor - meteorites - could have survived the fall to Earth, and they have begun gathering data to aid the search.
The fireball flew eastward over southern California, was observed in Nevada and Arizona, and was last seen disintegrating in the sky over Phoenix, the Arizona state capital, according to media reports, eyewitnesses and astronomers.
Many of those who saw the phenomenon telephoned the authorities after capturing it on mobile phone cameras. The footage spread across Twitter and the news media on Thursday.
"It was closer than a shooting star, and you could see it breaking up into pieces," said Sgt Mark Clark of the Scottsdale, Arizona police department, who witnessed it.
If found, those meteorites could yield further clues about the origins of our solar system and the chemistry and physical make-up of other celestial bodies.
'Building blocks'
"Most meteorites are older than any of the rocks that are found on the earth," said Prof Peter Brown, professor of physics and astronomy at the University of Western Ontario.
"They are essentially the primordial building blocks of the solar system."
The fireball was most likely caused by a piece of space rock travelling about up to 20 miles (32km) per second, about 30 miles high when it burned up, scientists said.
The fireball was captured on mobile phone cameras "Fireballs happen somewhere on the Earth every day," said Paul Chodas, a research scientist with Nasa's Jet Propulsion Laboratory.
"This one was over a populated area, on a convenient time, in the early evening, and so it was widely seen and reported."
It appeared at about 1945 local time on Wednesday (0245 GMT, Thursday).
Scientific investigators are expected to consult a variety of sources as they try to get to the bottom of the fireball and attempt to narrow the meteorite search area.
These include eyewitnesses and a range of records and instruments, including satellites, astronomical cameras, radar, amateur video, CCTV and even dashboard cameras on police cars.
"Our colleagues will try to gather data and videos that they can use to triangulate the path and then they will be able to calculate where the meteorites are likely to be found," said Mr Chodas.
"With just word of mouth descriptions, it's not enough."
Crowdsourced search
Meteorites that survive the fiery fall through the Earth's atmosphere continue travelling tens of kilometres before they finally hit the ground.
To find them, searchers also take into account the direction and speed of winds high in the earth's atmosphere.
Once a search area has been modelled, often scientists will in effect crowdsource the meteorite hunt, asking local residents about damaged roofs and cars and asking them to join the search.
The meteorite that fell in Sudan was tracked from space, then found by a team of searchers "The trouble is there are lots of rocks all over the world, and the vast majority of unusual rocks that people think might be a meteorite do not pan out," said Alan MacRobert, senior editor at Sky and Telescope Magazine.
"If it attracts a magnet at all, if it has a thin, darkened, molten crust just a millimetre or two thick, that's a good sign."
In 2000, researchers in Canada's Yukon territory recovered 1kg of meteorites from a 25 sq mile (64 sq km) area, after a local pilot discovered the first fragments while driving across a frozen lake.
Jim Brook collected the samples without touching them, grabbing them in plastic bags and storing them in his freezer until he could provide them to the meteor scientists.
Eight years later, a team of more than 40 searchers, including students and staff from the University of Khartoum, found 47 meteorites in the Nubian desert of northern Sudan.
Astronomers had tracked the falling body through space from a telescope in Arizona, then predicted the broad area of its impact.
Where to look
Eyewitnesses in the town of Wadi Halfa and at a train station between there and Khartoum reported witnessing the fireball, and US government satellites also sensed it.
"We just lined 45 people up and did a foot search," said Dr Peter Jenniskens, a meteor astronomer with the Seti Institute in California, who helped lead the hunt.
"We had everybody about 10-20 metres apart and started walking the desert."
It took about two hours, "but that was because we knew where to look".
Dr Brown of the University of Western Ontario, who is familiar with the Sudan meteorites, said the space rocks were found within 100m of their predicted target.
With the Arizona fireball - should it have dropped meteorites - researchers will be aided by the fact it would have fallen over a more densely populated area relative to northern Canada and the Sudanese desert, scientists say.
"We've populated our country so densely there's a chance something may have fallen into a building or a car," Dr Jenniskens said.
"It would be a great help."
Declassified US spy satellites reveal rare look at Cold War space program
From MSNBC: Declassified US spy satellites reveal rare look at Cold War space program
CHANTILLY, Va. — Twenty-five years after their top-secret, Cold War-era missions ended, two clandestine American satellite programs were declassified Saturday, with the agency unveiling three of the United States' most closely guarded assets: the KH-7 GAMBIT, the KH-8 GAMBIT 3 and the KH-9 HEXAGON spy satellites.
The vintage National Reconnaissance Office satellites were displayed to the public Saturday in a one-day-only exhibit here at the Smithsonian National Air & Space Museum's Udvar-Hazy Center at Dulles Airport, Va. The three spacecraft are the centerpiece of the NRO's invitation-only 50th Anniversary Gala celebration held at the center later that evening.
Saturday's spysat unveiling was attended by a number of jubilant NRO veterans who developed and refined the classified spacecraft and their components for decades in secret, finally able to show their wives and families what they actually did 'at the office' for so many years. Both of the newly declassified satellite systems, GAMBIT and HEXAGON, followed the U.S. military's frontrunner spy satellite system CORONA, which was declassified in 1995.
Big spy satellites revealed
The KH-9 HEXAGON, often referred to by its popular nickname "Big Bird," lived up to its legendary expectations. As large as a school bus, the KH-9 HEXAGON carried 60 miles of high resolution photographic film for space surveillance missions.
The Hexagon's panoramic cameras rotated as they swept back and forth while the satellite flew over Earth, a process intelligence officials referred to as "mowing the lawn."
Each 6-inch-wide frame of HEXAGON film captured a wide swath of terrain covering 370 nautical miles — the distance from Cincinnati to Washington — on each pass over the former Soviet Union and China. The satellites had a resolution of about 2 to 3 feet (0.6 to nearly 1 meter), according to the NRO. [10 Ways the Government Watches You]
According to documents released by the NRO, each HEXAGON satellite mission lasted about 124 days, with the satellite launching four film return capsules that could send its photos back to Earth. An aircraft would catch the return capsules in mid-air by snagging their parachutes following the canisters' re-entry.
The NRO launched 20 HEXAGON satellites from California’s Vandenberg Air Force Base from June 1971 to April 1986.
The HEXAGON's final launch in April 1986 — just weeks after the Space Shuttle Challenger explosion — also met with disaster as the spy satellite’s Titan 34D booster erupted into a massive fireball just seconds after liftoff, crippling the NRO's orbital reconnaissance capabilities for many months.
The spy satellite GAMBIT
Before the first HEXAGON spy satellite systems ever launched, the NRO's GAMBIT series of reconnaissance craft flew several space missions aimed at providing surveillance over specific targets around the world.
The satellite program's initial system, GAMBIT 1, first launched in 1963 carrying a KH-7 camera system that included a "77-inch focal length camera for providing specific information on scientific and technical capabilities that threatened the nation," according to an NRO description. A second GAMBIT satellite system, which first launched aboard GAMBIT 3 in 1966, included a175-inch focal length camera.
The GAMBIT 1 series satellite has a resolution similar to the HEXAGON series, about 2 to 3 feet, but the follow-up GAMBIT 3 system had an improved resolution of better than 2 feet, NRO documents reveal.
Both satellites were huge and launched out of Vandenberg Air Force Base.
The satellite series' initial version was 15 feet (4.5 m) long and 5 feet (1.5 m) wide, and weighed about 1,154 pounds (523 kilograms). The GAMBIT 3 satellite was the same width but longer, stretching nearly 29 feet (9 m) long, not counting its Agena D rocket. It weighed about 4,130 pounds (1,873 kg).
Unlike the follow-up HEXAGON satellites, the GAMBIT series were designed for extremely short missions.
The GAMBIT 1 craft had an average mission life of about 6 1/2 days. A total of 38 missions were launched, though 10 of them were deemed failures, according to NRO documents.
The GAMBIT 3 series satellites had missions that averaged about 31 days. In all, 54 of the satellites were launched, with four failures recorded.
Like the CORONA and HEXAGON programs, the GAMBIT series of satellites returned their film to Earth in re-entry capsules that were then snatched up by recovery aircraft. GAMBIT 1 carried about 3,000 feet (914 meters) of film, while GAMBIT 3 was packed with 12,241 feet (3,731 meters) of film, NRO records show.
The GAMBIT satellite program was active from July 1963 to April 1984.
CHANTILLY, Va. — Twenty-five years after their top-secret, Cold War-era missions ended, two clandestine American satellite programs were declassified Saturday, with the agency unveiling three of the United States' most closely guarded assets: the KH-7 GAMBIT, the KH-8 GAMBIT 3 and the KH-9 HEXAGON spy satellites.
The vintage National Reconnaissance Office satellites were displayed to the public Saturday in a one-day-only exhibit here at the Smithsonian National Air & Space Museum's Udvar-Hazy Center at Dulles Airport, Va. The three spacecraft are the centerpiece of the NRO's invitation-only 50th Anniversary Gala celebration held at the center later that evening.
Saturday's spysat unveiling was attended by a number of jubilant NRO veterans who developed and refined the classified spacecraft and their components for decades in secret, finally able to show their wives and families what they actually did 'at the office' for so many years. Both of the newly declassified satellite systems, GAMBIT and HEXAGON, followed the U.S. military's frontrunner spy satellite system CORONA, which was declassified in 1995.
Big spy satellites revealed
The KH-9 HEXAGON, often referred to by its popular nickname "Big Bird," lived up to its legendary expectations. As large as a school bus, the KH-9 HEXAGON carried 60 miles of high resolution photographic film for space surveillance missions.
The Hexagon's panoramic cameras rotated as they swept back and forth while the satellite flew over Earth, a process intelligence officials referred to as "mowing the lawn."
Each 6-inch-wide frame of HEXAGON film captured a wide swath of terrain covering 370 nautical miles — the distance from Cincinnati to Washington — on each pass over the former Soviet Union and China. The satellites had a resolution of about 2 to 3 feet (0.6 to nearly 1 meter), according to the NRO. [10 Ways the Government Watches You]
According to documents released by the NRO, each HEXAGON satellite mission lasted about 124 days, with the satellite launching four film return capsules that could send its photos back to Earth. An aircraft would catch the return capsules in mid-air by snagging their parachutes following the canisters' re-entry.
The NRO launched 20 HEXAGON satellites from California’s Vandenberg Air Force Base from June 1971 to April 1986.
The HEXAGON's final launch in April 1986 — just weeks after the Space Shuttle Challenger explosion — also met with disaster as the spy satellite’s Titan 34D booster erupted into a massive fireball just seconds after liftoff, crippling the NRO's orbital reconnaissance capabilities for many months.
The spy satellite GAMBIT
Before the first HEXAGON spy satellite systems ever launched, the NRO's GAMBIT series of reconnaissance craft flew several space missions aimed at providing surveillance over specific targets around the world.
The satellite program's initial system, GAMBIT 1, first launched in 1963 carrying a KH-7 camera system that included a "77-inch focal length camera for providing specific information on scientific and technical capabilities that threatened the nation," according to an NRO description. A second GAMBIT satellite system, which first launched aboard GAMBIT 3 in 1966, included a175-inch focal length camera.
The GAMBIT 1 series satellite has a resolution similar to the HEXAGON series, about 2 to 3 feet, but the follow-up GAMBIT 3 system had an improved resolution of better than 2 feet, NRO documents reveal.
Both satellites were huge and launched out of Vandenberg Air Force Base.
The satellite series' initial version was 15 feet (4.5 m) long and 5 feet (1.5 m) wide, and weighed about 1,154 pounds (523 kilograms). The GAMBIT 3 satellite was the same width but longer, stretching nearly 29 feet (9 m) long, not counting its Agena D rocket. It weighed about 4,130 pounds (1,873 kg).
Unlike the follow-up HEXAGON satellites, the GAMBIT series were designed for extremely short missions.
The GAMBIT 1 craft had an average mission life of about 6 1/2 days. A total of 38 missions were launched, though 10 of them were deemed failures, according to NRO documents.
The GAMBIT 3 series satellites had missions that averaged about 31 days. In all, 54 of the satellites were launched, with four failures recorded.
Like the CORONA and HEXAGON programs, the GAMBIT series of satellites returned their film to Earth in re-entry capsules that were then snatched up by recovery aircraft. GAMBIT 1 carried about 3,000 feet (914 meters) of film, while GAMBIT 3 was packed with 12,241 feet (3,731 meters) of film, NRO records show.
The GAMBIT satellite program was active from July 1963 to April 1984.
New planet; deep space exploration: is NASA bouncing back
From The Washington Post, blog Post: New planet; deep space exploration: is NASA bouncing back?
Two months ago, it seemed as if the whole world was composing a dirge for NASA. With the space shuttle program ending after 30 years, the media wondered if the agency would ever be able to find its footing. Then, the shuttle backup plan — catching a ride on Russian flights — was delayed, and the possibility of shuttering the International Space Station rose for the first time since 2000.
This week, though, a series of news-catching announcements seems to suggest the agency is doing just fine, with or without its shuttle program.
Space fans were introduced to two planet discoveries and a giant shuttle planned for deep space exploration.
NASA Administrator Charles Bolden participates in a news conference to introduce the design of the new Space Launch System. (Chip Somodevilla/Getty Images)
On Monday, NASA announced a “Super Earth,” a planet that could possibly have water and may be habitable.
On Wednesday, the agency announced plans for a massive rocket capable of lifting 70 to 100 metric tons that will explore the deep reaches of space.
On Thursday, an even more exciting announcement for Sci-Fi fans: plucked from the “Star Wars” script, astronomers discovered a planet with two suns, much like the famous “Star Wars” home of Luke Skywalker, Tatooine.
(Brian Vastag got this memorable quote from one of the planet’s discovery team members, astronomer Alan Boss of the Carnegie Institution of Washington: “It’d be a weird cocktail hour. The sun would go down, and you’d have a drink, and then, a few hours later, the other sun would go down while you have another drink.”)
The Post’s Vastag said that while the planet discoveries are definitely exciting, the shuttle plans were still uncertain, as Congress has yet to fund it.
Despite some Senate backing for the plan, the House has yet to support it. The estimated five-year price tag for the project is $18 billion. The House has been the most adamant about cutting NASA’s budget. The House proposal for the 2012 fiscal year is $2 billion less than for 2011. Seeking House approval for an $18 billion project may be a tough sell.
Even if it doesn’t become a reality, NASA still proved this week it has the power to inspire great dreams.
Monday, September 12, 2011
Trouble for the Space Station
From The Hindu: Trouble for the Space Station
It was in July 2011 that the last of the Space Shuttles, Atlantis, made the final trip to the International Space Station. With the Shuttles' retirement, only Russia's Soyuz spacecraft can transport crew to and from the huge station that is orbiting the earth. But with a question mark hanging over the Soyuz rocket that launches the manned capsule, there is a very real possibility that the station might have to be temporarily abandoned. The issue arose after a Soyuz rocket, which lifted off from the Baikonur cosmodrome on August 24, malfunctioned.
The Progress cargo vessel it was carrying, with supplies for the space station, ended up crashing to the ground. The loss of those supplies is not a cause for concern as the station is well-stocked and can easily support the three Russians, two Americans, and one Japanese who are currently living aboard for several months. The problem is that the replacement crew, who are scheduled to leave for the station on September 21, is likely to be delayed while the Russians make sure it is safe for them to travel on the Soyuz rocket.
But the astronauts on the space station may not be able to remain till the next crew arrive. That's because the two Soyuz capsules docked to the space station, in which they are to return home, are time-limited. Each of those capsules is certified to remain in space for only 200 days. Consequently, one set of three astronauts is now expected to leave the space station later this month and the remaining three in mid-November.
The Soyuz rocket is a lineal descendant of the launcher that carried the world's first satellite, Sputnik, and subsequently the first human to travel in to space, Yuri Gagarin. A production defect has been identified as the culprit in the latest failure. A week earlier, a Proton rocket with a communications satellite onboard developed trouble. Last December, another Proton rocket failed, followed by a Rokot booster this February. Some media reports suggest that poor pay, an ageing workforce, and inadequate state support are leading to a decline in quality standards in Russia's once well-funded space sector.
After the Soyuz failure, the Russian government ordered an industry-wide review and improvement of quality control procedures. It is, however, clearly desirable to have an alternative to the Soyuz capsule and rocket, which can provide much-needed back-up. But it could take a few years for U.S. spaceflight companies, like Space Exploration Technologies (SpaceX), to develop the necessary man-rated space hardware. Till then, Russia will have to shoulder the responsibility for taking astronauts to and from the International Space Station.
It was in July 2011 that the last of the Space Shuttles, Atlantis, made the final trip to the International Space Station. With the Shuttles' retirement, only Russia's Soyuz spacecraft can transport crew to and from the huge station that is orbiting the earth. But with a question mark hanging over the Soyuz rocket that launches the manned capsule, there is a very real possibility that the station might have to be temporarily abandoned. The issue arose after a Soyuz rocket, which lifted off from the Baikonur cosmodrome on August 24, malfunctioned.
The Progress cargo vessel it was carrying, with supplies for the space station, ended up crashing to the ground. The loss of those supplies is not a cause for concern as the station is well-stocked and can easily support the three Russians, two Americans, and one Japanese who are currently living aboard for several months. The problem is that the replacement crew, who are scheduled to leave for the station on September 21, is likely to be delayed while the Russians make sure it is safe for them to travel on the Soyuz rocket.
But the astronauts on the space station may not be able to remain till the next crew arrive. That's because the two Soyuz capsules docked to the space station, in which they are to return home, are time-limited. Each of those capsules is certified to remain in space for only 200 days. Consequently, one set of three astronauts is now expected to leave the space station later this month and the remaining three in mid-November.
The Soyuz rocket is a lineal descendant of the launcher that carried the world's first satellite, Sputnik, and subsequently the first human to travel in to space, Yuri Gagarin. A production defect has been identified as the culprit in the latest failure. A week earlier, a Proton rocket with a communications satellite onboard developed trouble. Last December, another Proton rocket failed, followed by a Rokot booster this February. Some media reports suggest that poor pay, an ageing workforce, and inadequate state support are leading to a decline in quality standards in Russia's once well-funded space sector.
After the Soyuz failure, the Russian government ordered an industry-wide review and improvement of quality control procedures. It is, however, clearly desirable to have an alternative to the Soyuz capsule and rocket, which can provide much-needed back-up. But it could take a few years for U.S. spaceflight companies, like Space Exploration Technologies (SpaceX), to develop the necessary man-rated space hardware. Till then, Russia will have to shoulder the responsibility for taking astronauts to and from the International Space Station.
Sunday, September 11, 2011
What Terror Looks Like From Space; NASA 9/11 Video
From Forex TV: What Terror Looks Like From Space; NASA 9/11 Video
Astronaut Frank Culbertson was the lone American not on the planet at the moment the 9/11 attacks took place. Culbertson was floating in orbit far above the evil that was unleashed and unaware of the destruction that had choked the skies on the ground.
Expedition 3 Commander Frank Culbertson was aboard the International Space Station at the time of the attacks, and the only American on the crew. As soon as he learned of the attacks, he began documenting the event in photographs because the station was flying over the New York City area. He captured incredible images in the minutes and hours following the event. From his unique vantage point in space, he recorded his thoughts of the world changing beneath him.
Yet, even from his perch in space, Culbertson reports that the face of evil was evident.
"The smoke seemed to have an odd bloom to it at the base of the column that was streaming south of the city. After reading one of the news articles we just received, I believe we were looking at NY around the time of, or shortly after, the collapse of the second tower. How horrible…" wrote Culbertson.
The following day, he posted a public letter that captured his initial thoughts of the events as they unfolded. "The world changed today. What I say or do is very minor compared to the significance of what happened to our country today when it was attacked."
Culbertson said, "It's horrible to see smoke pouring from wounds in your own country from such a fantastic vantage point. The dichotomy of being on a spacecraft dedicated to improving life on the earth and watching life being destroyed by such willful, terrible acts is jolting to the psyche, no matter who you are."
Astronaut Frank Culbertson was the lone American not on the planet at the moment the 9/11 attacks took place. Culbertson was floating in orbit far above the evil that was unleashed and unaware of the destruction that had choked the skies on the ground.
Expedition 3 Commander Frank Culbertson was aboard the International Space Station at the time of the attacks, and the only American on the crew. As soon as he learned of the attacks, he began documenting the event in photographs because the station was flying over the New York City area. He captured incredible images in the minutes and hours following the event. From his unique vantage point in space, he recorded his thoughts of the world changing beneath him.
Yet, even from his perch in space, Culbertson reports that the face of evil was evident.
"The smoke seemed to have an odd bloom to it at the base of the column that was streaming south of the city. After reading one of the news articles we just received, I believe we were looking at NY around the time of, or shortly after, the collapse of the second tower. How horrible…" wrote Culbertson.
The following day, he posted a public letter that captured his initial thoughts of the events as they unfolded. "The world changed today. What I say or do is very minor compared to the significance of what happened to our country today when it was attacked."
Culbertson said, "It's horrible to see smoke pouring from wounds in your own country from such a fantastic vantage point. The dichotomy of being on a spacecraft dedicated to improving life on the earth and watching life being destroyed by such willful, terrible acts is jolting to the psyche, no matter who you are."
Saturday, September 10, 2011
Nasa on the track of lunar Grail
From News Scotsman.com: Nasa on the track of lunar Grail
By Angus Howarth
By Angus Howarth
NASA has launched twin probes called Grail to the Moon to map tiny variations in the pull of gravity.
The information should give scientists fresh insight into the internal structure of Earth's satellite and is expected to help explain many mysteries, such as why the far side of the Moon looks so different from that of the near side, with its swathe
ADVERTISEMENT of dark volcanic plains. The data also will be an invaluable navigation tool for future exploration, enabling more precise landings.
A Delta rocket sent the Grail twins on their way from Cape Canaveral in Florida yesterday. The journey is a slow cruise, however. The duo are not expected to enter into the Moon's orbit until the turn of the year.The near side of the Moon is covered in smooth, dark material created by magma flooding on to the surface. The far side is more rugged, with a thicker crust pock-marked by impact craters.
"The improvement that Grail will have for the gravity field on the nearside is a factor of 100 better than we have now, and on the farside it is a factor of 1,000," said Grail programme scientist Dr Robert Fogel.
"Imagine trying to see something microscopic with your own eyes and then putting a lens in front of them that has 100 times power or 1,000 times power - it becomes a different world; and that's what we'll get with Grail."
Grail is an acronym for gravity recovery and internal laboratory.
Atlantis space shuttle crew visits Aviano schools
From Stars and Stripes: Atlantis space shuttle crew visits Aviano schools
AVIANO AIR BASE, Italy — Students whose parents work for the 31st Fighter Wing are used to watching jets soar into the sky. On Friday, a group of elementary students got to meet some really high fliers: The astronauts who flew the last U.S. space shuttle mission wrapped up a tour of U.S. military facilities in Turkey and Italy with visits to Aviano schools.
“While you were enjoying your summer vacation, we were busy up in space,” Chris Ferguson, commander of the Atlantis shuttle flight told students gathered at an assembly of third- to fifth-graders, most of whon raised their hands when asked if they wanted to be astronauts.
Fifth-grade aspiring astronaut Julia Gabel got to talk with crewmember Sandy Magnus and got all four crewmembers to sign her book.
“She’s going to be an astronaut one day,” Magnus told Ferguson.
Students asked questions, including how the toilet situation works (it’s complicated), if they can see the moon from up there (yes) and do you have to go to college to become an astronaut (most definitely yes).
Ferguson, a former Navy F-14 pilot, said answering such questions and meeting the public is part of the job. After flying back to Houston, Magnus – a civilian – and Doug Hurley – an active duty Marine F/A-18 pilot –will travel north to make an appearance at a NASCAR race. Ferguson and Rex Walheim – a former Air Force officer – will get a few days off.
Now that the space shuttle mission has ended, the astronaut program is in a state of flux, Ferguson said. After reaching its high point with 149 astronauts in 1998, it’s down to 60 now and has been “decreasing rapidly,” he said.
It’s not that astronauts don’t believe in NASA or the space program, he said. For pilots like himself, riding to the International Space Station on a Russian space ship is not the same. Still, he said he fully supports NASA and the continued exploration of space.
“It’s very hard to go and present the case that we have to go to Mars when the country is $14 trillion in debt,” he said. “It’s a hard thing, because it takes years for these things to happen, and politicians and people want quick results.”
If the students at Aviano were voting, however …
AVIANO AIR BASE, Italy — Students whose parents work for the 31st Fighter Wing are used to watching jets soar into the sky. On Friday, a group of elementary students got to meet some really high fliers: The astronauts who flew the last U.S. space shuttle mission wrapped up a tour of U.S. military facilities in Turkey and Italy with visits to Aviano schools.
“While you were enjoying your summer vacation, we were busy up in space,” Chris Ferguson, commander of the Atlantis shuttle flight told students gathered at an assembly of third- to fifth-graders, most of whon raised their hands when asked if they wanted to be astronauts.
Fifth-grade aspiring astronaut Julia Gabel got to talk with crewmember Sandy Magnus and got all four crewmembers to sign her book.
“She’s going to be an astronaut one day,” Magnus told Ferguson.
Students asked questions, including how the toilet situation works (it’s complicated), if they can see the moon from up there (yes) and do you have to go to college to become an astronaut (most definitely yes).
Ferguson, a former Navy F-14 pilot, said answering such questions and meeting the public is part of the job. After flying back to Houston, Magnus – a civilian – and Doug Hurley – an active duty Marine F/A-18 pilot –will travel north to make an appearance at a NASCAR race. Ferguson and Rex Walheim – a former Air Force officer – will get a few days off.
Now that the space shuttle mission has ended, the astronaut program is in a state of flux, Ferguson said. After reaching its high point with 149 astronauts in 1998, it’s down to 60 now and has been “decreasing rapidly,” he said.
It’s not that astronauts don’t believe in NASA or the space program, he said. For pilots like himself, riding to the International Space Station on a Russian space ship is not the same. Still, he said he fully supports NASA and the continued exploration of space.
“It’s very hard to go and present the case that we have to go to Mars when the country is $14 trillion in debt,” he said. “It’s a hard thing, because it takes years for these things to happen, and politicians and people want quick results.”
If the students at Aviano were voting, however …
Large satellite crashing to earth next month, says NASA
From: Large satellite crashing to earth next month, says NASA
By Derrol Nail
FOX 35 News
KENNEDY SPACE CENTER, Fla. (WOFL FOX 35) - Have you ever wished that a shooting star won’t end up hitting and killing you? Well, it's not totally out of the realm of possibility, NASA informed us on Friday.
Back in 1991, the space shuttle put an Upper Atmosphere Research Satellite into orbit to study human effects on the ozone layer. Twenty years later, and NASA informs us it's going to come crashing back to earth.
The space agency says the UARS satellite will de-orbit sometime in October, but no one knows where the 26-pieces that will survive re-entry will land.
"It will have what we call an uncontrolled re-entry” said NASA Kennedy Space Center spokesman Allard Beutel. “They can’t be brought down in a specific place, it's just wherever they come down."
So, that begs the question: what are the chances it will hit one of the 6.7 billion people on our planet? NASA has assigned the odds at 3,200 to 1.
"In fifty plus years of the space age, no one has been hit by a piece of falling satellite" said Beutel.
That’s because most satellite chunks that survive the disintegrating heat of re-entry land in the water, which covers roughly 3/4ths of the earth’s surface. Still, some have hit land.
In 1979, parts of the space station Skylab broke apart and rained down over the Australian outback. In 2001, a rocket chunk crashed in the sparsely populated Saudi Arabian desert. And parts of space shuttle Columbia accident reached the ground in 2003. But no one was ever hit.
"You just go with the odds. And statistically, the chances of it being over a populated area are very, very small."
The UARS satellite was launched before 1995. That’s the year NASA started requiring all satellites be built with fewer heavy components capable of making it through the earth’s atmosphere.
By Derrol Nail
FOX 35 News
KENNEDY SPACE CENTER, Fla. (WOFL FOX 35) - Have you ever wished that a shooting star won’t end up hitting and killing you? Well, it's not totally out of the realm of possibility, NASA informed us on Friday.
Back in 1991, the space shuttle put an Upper Atmosphere Research Satellite into orbit to study human effects on the ozone layer. Twenty years later, and NASA informs us it's going to come crashing back to earth.
The space agency says the UARS satellite will de-orbit sometime in October, but no one knows where the 26-pieces that will survive re-entry will land.
"It will have what we call an uncontrolled re-entry” said NASA Kennedy Space Center spokesman Allard Beutel. “They can’t be brought down in a specific place, it's just wherever they come down."
So, that begs the question: what are the chances it will hit one of the 6.7 billion people on our planet? NASA has assigned the odds at 3,200 to 1.
"In fifty plus years of the space age, no one has been hit by a piece of falling satellite" said Beutel.
That’s because most satellite chunks that survive the disintegrating heat of re-entry land in the water, which covers roughly 3/4ths of the earth’s surface. Still, some have hit land.
In 1979, parts of the space station Skylab broke apart and rained down over the Australian outback. In 2001, a rocket chunk crashed in the sparsely populated Saudi Arabian desert. And parts of space shuttle Columbia accident reached the ground in 2003. But no one was ever hit.
"You just go with the odds. And statistically, the chances of it being over a populated area are very, very small."
The UARS satellite was launched before 1995. That’s the year NASA started requiring all satellites be built with fewer heavy components capable of making it through the earth’s atmosphere.
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