NASA's Phoenix Mars Lander inserted the four needles of its thermal and
conductivity probe into Martian soil during the 98th Martian day, or sol,
of the mission and left it in place until Sol 99 (Sept. 4, 2008).
The Surface Stereo Imager on Phoenix took this image on the morning of Sol
99 after the probe was lifted away from the soil. This imaging served as a
check of whether soil had stuck to the needles.
The thermal and conductivity probe measures how fast heat and electricity
move from one needle to an adjacent one through the soil or air between
the needles. Conductivity readings can be indicators about water vapor,
water ice and liquid water.
The probe is part of Phoenix's Microscopy, Electrochemistry and
Conductivity suite of instruments.
The Phoenix Mission is led by the University of Arizona, Tucson, on behalf
of NASA. Project management of the mission is by NASA's Jet Propulsion
Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin
Space Systems, Denver.