Mars Lander Gets Another Sample In Oven
NASA's Phoenix Mars Lander's Surface Stereo Imager took this false color image on Sol 72 (August 7, 2008), the 72nd Martian day after landing. It shows a dirt sample from a trench informally called "Rosy Red" after being delivered to a gap between partially opened doors on the lander's Thermal and Evolved-Gas Analyzer, or TEGA.
Credit: NASA/JPL-Caltech/University of Arizona/Texas A&M University

NASA's Phoenix Mars Lander has successfully dumped another sample of surface dirt into its ovens for analysis, mission scientists reported this weekend.

Phoenix's robotic arm delivered dirt Thursday from a trench informally named "Rosy Red" through a narrow opening to a screen above the No. 5 oven on the lander's Thermal and Evolved-Gas Analyzer (TEGA). TEGA heats up the samples in its oven and then analyzes the vapors given off to help determine the composition of the Martian dirt.

The $420 million Phoenix mission is designed to analyze the surface dirt and underlying ice in the arctic regions of Mars to assess whether or not the area might have been habitable at some point in the past.

A few particles of the sample passed through the screen on Thursday, but not enough to fill the oven and allow analysis of the sample to begin. The Phoenix team sent commands for TEGA to vibrate the screen again on Friday, and more material reached the oven, though still not enough to proceed with analysis.

"There appear to be clumps blocking the opening," said Phoenix science lead Doug Ming of NASA Johnson Space Center, in Houston, on Friday.

Vibration of the screen on Saturday finally succeeded in getting enough dirt into the oven to begin analysis. The team sent instructions to begin analysis of the sample on Sunday.

Phoenix scientists will be looking for signs of perchlorate, a highly oxidizing substance that was detected in dirt samples by the lander's wet chemistry laboratory. The last sample analyzed by TEGA found no indications of any chlorine present

On Friday, the spacecraft also extended the width of an exploratory trench informally named "Neverland," which runs between two rocks on the surface of the ground.

Phoenix also took overnight measurements of the conductivity of the Martian regolith that were completed on Wednesday. A fork-like probe inserted into the dirt checks how well heat and electricity move through the dirt from one prong to another.

Phoenix's mission, originally slated to end at the end of August, has been extended to Sept. 30.