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Phoenix Mars Lander is Silent, New Image Shows Damage

Copyright NASA

NASA’s Phoenix Mars Lander has ended operations after repeated attempts to contact the spacecraft were unsuccessful. A new image transmitted by NASA’s Mars Reconnaissance Orbiter shows signs of severe ice damage to the lander’s solar panels.

“The Phoenix spacecraft succeeded in its investigations and exceeded its planned lifetime,” said Fuk Li, manager of the Mars Exploration Program at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Although its work is finished, analysis of information from Phoenix’s science activities will continue for some time to come.”

Last week, NASA’s Mars Odyssey orbiter flew over the Phoenix landing site 61 times during a final attempt to communicate with the lander. No transmission from the lander was detected. Phoenix also did not communicate during 150 flights in three earlier listening campaigns this year.

Earth-based research continues on discoveries Phoenix made during summer conditions at the far-northern site where it landed May 25, 2008. The solar-powered lander completed its three-month mission and kept working until sunlight waned two months later.

Phoenix was not designed to survive the dark, cold, icy winter. However, the slim possibility Phoenix survived could not be eliminated without listening for the lander after abundant [...]

Europe reaches new frontier -Huygens lands on Titan


Copyright ESA

ESA PR 03-2005. Today, after its seven-year journey through the Solar System on board the Cassini spacecraft, ESA’s Huygens probe has successfully descended through the atmosphere of Titan, Saturn’s largest moon, and safely landed on its surface.

The first scientific data arrived at the European Space Operations Centre (ESOC) in Darmstadt, Germany, this afternoon at 17:19 CET. Huygens is mankind’s first successful attempt to land a probe on another world in the outer Solar System. “This is a great achievement for Europe and its US partners in this ambitious international endeavour to explore the Saturnian system,” said Jean-Jacques Dordain, ESA’s Director General.

Following its release from the Cassini mothership on 25 December, Huygens reached Titan’s outer atmosphere after 20 days and a 4 million km cruise. The probe started its descent through Titan’s hazy cloud layers from an altitude of about 1270 km at 11:13 CET. During the following three minutes Huygens had to decelerate from 18 000 to 1400 km per hour.

A sequence of parachutes then slowed it down to less than 300 km per hour. At a height of about 160 km the probe’s scientific instruments were exposed to Titan’s atmosphere. At about 120 km, [...]

Landers feel the heat on space missions


Copyright ESA

Space is certainly a cold place, but spacecraft have to face extremely high temperatures when they are exposed to the Sun’s radiation. However, there are other extreme situations in which spacecraft are subject to tremendous heat. ESA’s spacecraft must endure temperatures from hell…

When a lander plunges at high speed through the atmosphere of an alien planet, things can get very hot. This rise in temperature comes from the friction between the landing craft and the atmosphere. The heat can become as intense as several thousands of degrees Celsius. Con McCarthy is a senior engineer on Mars Express, due to start its journey to the Red Planet later in 2003. He explains the process is similar to putting the brakes on when driving a car. “When you apply the brakes to a fast-moving car, they convert all the energy being used in the car’s forward motion into heat. This makes the brake disks burning hot. Similarly, when a lander enter into a planet’s atmosphere at very high speed, a great deal of heat will be generated by friction.”

The Beagle 2 lander

Beagle 2 lander deployed on Mars

Landers have to be well prepared to withstand such vicious [...]

Challenges of landing on alien worlds


Copyright ESA

Three ESA missions are due to send down robotic ‘spaceprobes’ when they arrive at their alien destinations. Since these craft will be going where no one has gone before, how can scientists be sure what it will be like down there? How do you ensure that your spaceprobe is prepared for anything?

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°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.

A typical weather update

Dust storms such as these on Mars complicate landings

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 [...]

Beagle 2 landing site selected


The Mars Express lander, Beagle 2, will land on Isidis Planitia, a large flat region that overlies the boundary between the ancient highlands and the northern plains. The choice of site was announced last week at a meeting of the Mars Express science working team in ESTEC, Noordwijk, the Netherlands.

The region appears to be a sedimentary basin where traces of life could have been preserved, if primitive life really did exist at some time on Mars. “This is the best site given the landing constraints and scientific aims of Beagle 2,” said John Bridges from the Natural History Museum, London, who has been assessing several sites on behalf of the project.

Isidis Planitia, the third largest impact basin on Mars, lies between latitudes of 5° and 20° N. The specific site chosen lies close to 10° N, which is the maximum latitude for a site to be warm enough for Beagle 2 to function properly during early spring, the season at which it is due to land on Mars. The number of rocks on the surface seems to be about right – not too many to threaten a safe landing, but enough to provide an interesting landscape for [...]