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Challenges of landing on alien worlds EUROPEAN SPACE AGENCY SCIENCE RELEASE Posted: October 22, 2002
Experts take every precaution to ensure that these probes will not burn up entering an alien atmosphere, or meet a spectacular, untimely end via a crash landing on inhospitable terrain. These probes expect the worst. For example, the Huygens probe, which is currently on its journey to Titan, Saturn's largest moon, on-board the Cassini spacecraft, can withstand temperatures of up to 18,000 deg C in the shockwave in front of the heat shield. This is about three times the Sun's surface temperature. Why? The heat generated as Huygens travels through Titan's thick atmosphere will be immense. Jean-Pierre Lebreton, Huygens Project Scientist, says "Things will get interesting once Cassini draws close to Saturn. We'll get the best views of Saturn and Titan that we ever had. We'll also observe Titan to verify that our models are correct. If we find the atmospheric density is different from what we expected, we could consider slightly changing the angle at which Huygens enters to protect it from overheating or the parachute deploying wrongly. However, late changes may bring new risks." Scientists chose the site for the landing of the Mars Express lander, Beagle 2, very carefully. Isidis Planitia, the chosen site, is largely flat without too many rocks to jeopardise a safe landing. However, Mars's famous planetwide dust storms were taken into consideration. " Major dust storms are not expected to occur at the time and place of the landing. However, there may be strong lateral winds." says Mars Express Project Scientist Agustin Chicarro. ESA's Rosetta lander, which will be the first man-made object to land on a comet, has another set of challenges altogether. "Firstly, we don't know anything about how rough the surface is," says Rosetta Project Scientist Gerhard Schwehm. "It could be covered with fluffy snow like the Alps or it could be hard rocks and craters. We can, however, be sure that it will not be smooth and flat resembling parking lots." Scientists designed Rosetta's landing gear to cope with most nasty surprises as soon as it touches down on Comet Wirtanen in 2011. Two harpoons will anchor the probe to the surface. The self-adjusting landing gear will ensure that it stays upright, even on a slope. The lander's feet will drill into the ground. These devices will help counteract the fact that there is no gravity on a comet. Observations of Mars, Titan, and Comet Wirtanen will continue frantically while the spacecrafts approach their final destination. In this way, scientists will be able to make last-minute adjustments to the timing of the landing. Information from other space missions and ground-based observations will increase scientists' understanding about the targets of the missions. In Rosetta's case, this will help to determine the comet's probable size and speed of rotation. These will help improve our 'models' for comet behaviour. However, for Rosetta, they may come too late. "We'll just have to see if the models we're using are good enough" says Schwehm.
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Hubble Calendar
NEW! This remarkable calendar features stunning images of planets, stars, gaseous nebulae, and galaxies captured by NASA's orbiting Hubble Space Telescope . Gemini 7 Gemini 7: The NASA Mission Reports covers this 14-day mission by Borman and Lovell as they demonstrated some of the more essential facts of space flight. Includes CD-ROM.U.S. - U.K. - E.U. - Worldwide Apollo patches The Apollo Patch Collection: Includes all 12 Apollo mission patches plus the Apollo Program Patch. Save over 20% off the Individual price. U.S. - U.K. - E.U. - Worldwide Mars Rover mission patch A mission patch featuring NASA's Mars Exploration Rover is available from our online.U.S. - U.K. - E.U. - Worldwide Apollo 9 DVD On the road to the moon, the mission of Apollo 9 stands as an important gateway in experience and procedures. This 2-DVD collection presents the crucial mission on the voyage to the moon.U.S. - U.K. - E.U. - Worldwide Apollo 15 DVDs Bring a unique piece of space history to your living room. Two- and six-disc Apollo 15 DVDs will be shipping soon.Hubble Astronomy Now presents Hubble: the space telescope's view of the cosmos. A collection of the best images from the world’s premier space observatory. Gemini 12: The NASA Mission Reports covers the voyage of James Lovell and Buzz Aldrin that capped the Gemini program's efforts to prove the technologies and techniques that would be needed for the Apollo Moon landings. Includes CD-ROM.U.S. - U.K. - E.U. - Worldwide Soviet Space For the first time ever available in the West. Rocket & Space Corporation Energia: a complete pictorial history of the Soviet/Russian Space Program from 1946 to the present day all in full color. Available from our store.U.S. - U.K. - E.U. - Worldwide Viking patch This embroidered mission patch celebrates NASA's Viking Project which reached the Red Planet in 1976.U.S. - U.K. - E.U. - Worldwide Apollo 7 DVD For 11 days the crew of Apollo 7 fought colds while they put the Apollo spacecraft through a workout, establishing confidence in the machine what would lead directly to the bold decision to send Apollo 8 to the moon just 2 months later.U.S. - U.K. - E.U. - Worldwide Gemini 12 Gemini 12: The NASA Mission Reports covers the voyage of James Lovell and Buzz Aldrin that capped the Gemini program's efforts to prove the technologies and techniques that would be needed for the Apollo Moon landings. Includes CD-ROM.U.S. - U.K. - E.U. - Worldwide Get e-mail updates Sign up for our NewsAlert service and have the latest news in astronomy and space e-mailed direct to your desktop (privacy note: your e-mail address will not be used for any other purpose). Expedition 18 patch & pin The official embroidered patch and lapel pin for the International Space Station Expedition 18 crew is now available to from our stores.Ares patch The Ares Project will develop two new rockets to launch astronauts back to the Moon under NASA's Vision for Exploration. The Ares 1 will employ a single space shuttle solid rocket booster to loft the Orion crew capsule. The gigantic Ares 5 will haul the equipment and cargo needed for such lunar voyages. This is the Ares emblem.![]() Apollo patches The Apollo Patch Collection: Includes all 12 Apollo mission patches plus the Apollo Program Patch. Save over 20% off the Individual price. U.S. STORE Columbus mission patch The official astronaut embroidered patch of Atlantis' STS-122 mission that launched the Columbus science lab in February is available to U.S. customers from our store. |
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