Polar explorer: Phoenix landed at 68.2 degrees north latitude, 234.2 degrees east longitude. The far-northern location of the site is indicated on this global view from the Mars Orbiter Camera on NASA's Mars Global Surveyor spacecraft.
Credit: NASA/JPL-Caltech/University of Arizona/MSSS
The MECA evidence came from a 'buffering effect' characteristic of calcium carbonate found in a wet chemical analysis of the soil. The measured concentration of calcium was exactly what would be expected for a solution buffered by calcium carbonate.
Furthermore, "we are seeing smooth-surfaced [flat] particles with the atomic-force microscope, not inconsistent with the appearance of clay particles," said Michael Hecht, MECA lead scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.
Falling into shadow
The Phoenix mission, originally planned for three months on Mars, is now in its fifth month. However, it faces a decline in solar energy that is expected to curtail the lander's activities before the end of the year.
"For nearly three months after landing, the Sun never went below the horizon at our landing site." said Barry Goldstein, JPL Phoenix project manager. "Now it is gone for more than four hours each night, and the output from our solar panels is dropping each week. Before the end of October, there won't be enough energy to keep using the robotic arm."
Before power totally ceases, the Phoenix team will attempt to activate a microphone on the lander to capture sounds on Mars.
With NASA.
