NASA's long-dormant Phoenix Mars Lander is broken and officiallydown for the count, with new images taken by an orbiting probe showing severedamage to the spacecraft's solar panels due to the harsh Martian winter.
Repeated attempts by NASA in recent months to reestablishcontact with Phoenixfollowing its winter hibernation were unsuccessful, with no peeps coming fromthe lander.
The new photos of Phoenix, sent by NASA's MarsReconnaissance Orbiter, indicate that the lander has suffered severe ice damageto at least one of its solar panels, NASA officials said Monday.
The discovery led NASA to declare that its Phoenix'smission has officially ended its prolonged mission. [Deadspacecraft on Mars.]
"The Phoenix spacecraft succeeded in its investigationsand exceeded its planned lifetime," said Fuk Li, manager of the MarsExploration Program at NASA's Jet Propulsion Laboratory in Pasadena, Calif."Although its work is finished, analysis of information from Phoenix'sscience activities will continue for some time to come."
Phoenix touched down in the arctic plains of VastitasBorealis in Mars' northern hemisphere on May 25, 2008 and spent several monthsdigging up the Martian soil, confirming the presence of water ice beneath thesurface.
Last week, NASA's Mars Odyssey orbiter flew over the Phoenixlanding site 61 times during a final attempt to communicate with thelander. No transmission from the lander was detected. Phoenix also did not communicateduring 150 flights in three previous listening campaigns earlier this year.
Slim chance of resurrection
Phoenix was not designed to survive the dark, cold, icywinter of the Martian arctic and mission managers were not optimistic they wouldhear from the spacecraft again after it fell silent in November 2008, when thesun dipped too low in the sky for Phoenix to get enough sunlight to poweritself and temperatures plummeted.
At the time, the $475 million landerhad already survived two months longer than planned. However, the slimpossibility Phoenix survived could not be eliminated without listening for thelander after abundant sunshine returned.
The new photo of Phoenix taken this month by the HighResolution Imaging Science Experiment, or HiRISE, camera on board the MarsReconnaissance Orbiter suggests the lander no longer casts shadows the way itdid during its working lifetime.
"Before and after images are dramaticallydifferent," said Michael Mellon of the University of Colorado in Boulder,a science team member for both Phoenix and HiRISE. "The lander lookssmaller, and only a portion of the difference can be explained by accumulationof dust on the lander, which makes its surfaces less distinguishable fromsurrounding ground."
Apparent changes in the shadows cast by the lander areconsistent with predictions of how Phoenixcould be damaged by harsh winter conditions. It was anticipatedthat the weight of a carbon-dioxide ice buildup could bend or break thelander's solar panels. Mellon calculated hundreds of pounds of ice probablycoated the lander in mid-winter.
Phoenix's icy success
During its mission, Phoenix confirmed and examined patchesof the widespread deposits of underground water ice detected by Odyssey andidentified a mineral called calcium carbonate that suggested occasionalpresence of thawed water.
The lander also found soil chemistry with significantimplications for life and observed falling snow.
The mission's biggest surprise was the discoveryof perchlorate, an oxidizing chemical on Earth that is food for somemicrobes and potentially toxic for others.
"We found that the soil above the ice can act like asponge, with perchlorate scavenging water from the atmosphere and holding on toit," said Peter Smith, Phoenix principal investigator at the University ofArizona in Tucson. "You can have a thin film layer of water capable ofbeing a habitable environment. A micro-world at the scale of grains of soil --that's where the action is."
The perchlorate results are shaping subsequent astrobiologyresearch, as scientists investigate the implications of its antifreezeproperties and potential use as an energy source by microbes.
- Images:Phoenix on Mars!
- MarsIs a Spacecraft Graveyard
- SPACE.comSpecial Report: Phoenix Mars Lander