|This is one of the newly posted images from more than 1,000 observations by the high resolution camera on NASA's Mars Reconnaissance Orbiter provided by NASA Thursday Sept. 18, 2008. This image shows the Dune Field in an Impact Crater Near Cerberus Fossae. AP Photo/NASA - JPL/University of Arizona|
Water Ice on Mars ConfirmedJuly 30, 2008
NASA's Phoenix Mars Lander has confirmed the existence of water ice on Mars.
Mission scientists celebrated the news after a sample of the ice was finally delivered to one of the lander's instruments. Phoenix's mission has also officially been extended for one month beyond its original mission, NASA announced today at a briefing at the University of Arizona at Tucson, where mission control is currently based.
"I'm very happy to announce that we've gotten an ice sample," said the University of Arizona's William Boynton, co-investigator for Phoenix's Thermal and Evolved-Gas Analyzer (TEGA), which heats up samples and analyzes the vapors they give off to determine their composition.
"We have water," Boynton added. "We've seen evidence for this water ice before in observations by the Mars Odyssey orbiter and in disappearing chunks observed by Phoenix last month, but this is the first time Martian water has been touched and tasted."
The news that ice had fallen into TEGA came on Thursday morning, surprising scientists who had run into problems delivering a sample of the icy dirt because of its unexpected stickiness.
"There were champagne corks popping in the downlink room," Boynton said. "It's something we've been waiting a long time for."
When scientists tried to deliver samples of icy dirt scraped up from the Snow White trench and deliver it to TEGA last week, the sample stuck to the scoop of Phoenix's robotic arm, with only a few tiny pieces of ice falling onto the oven screen. Scientists decided to deliver a second sample of dry dirt to the oven while they revised their sample delivery method.
The dry sample was scooped up and delivery to the oven was confirmed yesterday. When scientists began heating up the sample, the signal confirmed that "we got a little bit of ice mixed in with this sample," Boynton said.
Scientists could detect the water ice in the sample because when water begins to melt, more heat is needed to raise the temperature of the sample.
Boynton said he initially dubbed the sample "Wicked Witch" after the witch in "Hansel in Gretel" who met her end when she was shoved into an oven. While donning a green costume witch hat, to the laughter of those in the briefing room, he said perhaps he should have named it for the witch in "The Wizard of Oz," famous for her dying line, "I'm melting..."
Phoenix has also completed its color panorama view of its landing site, made of images taken with its Surface Stereo Imager. The images show the Martian terrain in the high arctic regions, which is relatively flat with few rocks and the hummocks and troughs that indicate subsurface ice.
"Essentially it's an ice-dominated terrain," said Mark Lemmon of Texas A&M University, lead scientist for Phoenix Surface Stereo Imager.
The completion of the panorama was one of the criteria Phoenix had to meet to achieve mission success, which Phoenix principal investigator Peter Smith said should be completely met by the end of the lander's primary mission of 90 sols, or Martian days.
Michael Meyer, chief scientist with Mars Exploration Program at NASA Headquarters in Washington, D.C., said that the mission would be extended through sol 124, or Sept. 30. The mission extension will tack another $2 million onto the $420 million mission.