Mars Lander Prepares for Second Ice Sample
This image, taken by NASA's Phoenix Mars Lander's Surface Stereo Imager on Sol 50, or the 50th day of the mission, July 15, 2008, shows two holes at the top created by the lander's Robotic Arm's motorized rasp tool. The holes are about 1 centimeter (0.4 inch) apart.
Credit: NASA/JPL-Caltech/University of Arizona/Texas A&M University

NASA scientists planned to instruct the Phoenix Mars Lander to test out its method for shaving and collecting ice for a second time Friday.

The test is in preparation for collecting a similar sample of ice to be analyzed in one of Phoenix's instruments in the coming days.

The ice scrapings will be placed into one of the tiny ovens in the lander's Thermal and Evolved-Gas Analyzer (TEGA), which heats up samples of Martian dirt and analyzes the vapors they give off. Mission team members hope that the TEGA analysis of the ice samples will show that they are rich in water ice, as some scientists expect.

Water is the key to life as we know it, and the lander, which touched down May 25, is designed to probe its location in the Martian arctic for conditions that might be hospitable to microbes. The 90-day mission is not designed to detect life.

The first test of the collecting method was conducted on July 15. The rasp on the end of the lander's scoop was used to scrape away some ice into the scoop. The test planned for Friday will be a little different.

"First, we will scrape the terrain before rasping, to expose fresh terrain for sampling," said Richard Volpe of NASA's Jet Propulsion Laboratory, in Pasadena, Calif., an engineer for the Phoenix robotic arm team. "Second, we will rasp four times in a row, twice the amount previously. Third, the scoop blade will be run across the rasp holes to pick up as much of the tailings as possible."

The scrapings are being taken from a 2-inch (5-centimeter) deep trench informally known as Snow White.

The sample for the TEGA instrument will also be taken from this trench. Mission controllers hope to collect and deliver the sample quickly and early in the Martian morning to minimize the amount of ice lost to sublimation.