Nov 10, 2008

Dwayne Brown Headquarters, Washington 202-358-1726 dwayne c brown@nasa gov

Guy Webster/Rhea Borja Jet Propulsion Laboratory, Pasadena, Calif 818-354-6278/0850 guy webster@jpl nasa gov, rhea r borja@jpl nasa gov

Lori Stiles University of Arizona, Tucson 520-626-4402 lstiles@email arizona edu

RELEASE: 08-284

MARS PHOENIX LANDER FINISHES SUCCESSFUL WORK ON RED PLANET

WASHINGTON -- NASA's Phoenix Mars Lander has ceased communications after operating for more than five months As anticipated, seasonal decline in sunshine at the robot's arctic landing site is not providing enough sunlight for the solar arrays to collect the power necessary to charge batteries that operate the lander's instruments

Mission engineers last received a signal from the lander on Nov 2 Phoenix, in addition to shorter daylight, has encountered a dustier sky, more clouds and colder temperatures as the northern Mars summer approaches autumn The mission exceeded its planned operational life of three months to conduct and return science data

The project team will be listening carefully during the next few weeks to hear if Phoenix revives and phones home However, engineers now believe that is unlikely because of the worsening weather conditions on Mars While the spacecraft's work has ended, the analysis of data from the instruments is in its earliest stages

"Phoenix has given us some surprises, and I'm confident we will be pulling more gems from this trove of data for years to come," said Phoenix Principal Investigator Peter Smith of the University of Arizona in Tucson

Launched Aug 4, 2007, Phoenix landed May 25, 2008, farther north than any previous spacecraft to land on the Martian surface The lander dug, scooped, baked, sniffed and tasted the Red Planet's soil Among early results, it verified the presence of water-ice in the Martian subsurface, which NASA's Mars Odyssey orbiter first detected remotely in 2002 Phoenix's cameras also returned more than 25,000 pictures from sweeping vistas to near the atomic level using the first atomic force microscope ever used outside Earth

"Phoenix not only met the tremendous challenge of landing safely, it accomplished scientific investigations on 149 of its 152 Martian days as a result of dedicated work by a talented team," said Phoenix Project Manager Barry Goldstein at NASA's Jet Propulsion Laboratory in Pasadena, Calif

Phoenix's preliminary science accomplishments advance the goal of studying whether the Martian arctic environment has ever been favorable for microbes Additional findings include documenting a mildly alkaline soil environment unlike any found by earlier Mars missions; finding small concentrations of salts that could be nutrients for life; discovering perchlorate salt, which has implications for ice and soil properties; and finding calcium carbonate, a marker of effects of liquid water

Phoenix findings also support the goal of learning the history of water on Mars These findings include excavating soil above the ice table, revealing at least two distinct types of ice deposits; observing snow descending from clouds; providing a mission-long weather record, with data on temperature, pressure, humidity and wind; observations of haze, clouds, frost and whirlwinds; and coordinating with NASA's Mars Reconnaissance Orbiter to perform simultaneous ground and orbital observations of Martian weather

"Phoenix provided an important step to spur the hope that we can show Mars was once habitable and possibly supported life," said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington "Phoenix was supported by orbiting NASA spacecraft providing communications relay while producing their own fascinating science With the upcoming launch of the Mars Science Laboratory, the Mars Program never sleeps "

The University of Arizona leads the Phoenix mission with project management at JPL and development partnership at Lockheed Martin Corporation in Denver International contributions came from the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus in Denmark; the Max Planck Institute in Germany; the Finnish Meteorological Institute; and Imperial College of London

For additional information about Phoenix mission findings, visit:

http://www nasa gov/phoenix

-end-

To subscribe to the list, send a message to: hqnews-subscribe@mediaservices nasa gov To remove your address from the list, send a message to: hqnews-unsubscribe@mediaservices nasa gov

The following information is a reminder of your current mailing list subscription:

You are subscribed to the following list: [list_name]

using the following email: example@example.com

You may automatically unsubscribe from this list at any time by visiting the following URL:

http://www aus-city com/cgi-bin/dada/plugins/dada_bridge pl/u/[list]/

If the above URL is inoperable, make sure that you have copied the entire address Some mail readers will wrap a long URL and thus break this automatic unsubscribe mechanism

You may also change your subscription by visiting this list's main screen:

<[program_url]/list/[list]>

If you're still having trouble, please contact the list owner at:

<mailto:[list_owner_email]>

The following physical address is associated with this mailing list:

[physical_address]