Mars Dirt Found Surprisingly Sticky

By Andrea Thompson Senior Writer posted: 29 July 2008 11:23 am ET

The icy dirt mixture that NASA's Phoenix Mars Lander is trying to sample is surprisingly sticky, mission scientists learned this weekend, as they tried to deliver a clump to one of the craft's instruments.

The difficulties of delivering the sticky dirt, thought to be a mixture of water ice and dust and other unknown minerals similar to terrestrial soil, but without microbes, to one of the ovens in Phoenix's Thermal and Evolved-Gas Analyzer (TEGA) are forcing scientists to delay those plans and dig for another sample of dry dirt instead. The lander analyzed its first dry dirt sample about a month ago.

"While we continue with determining the best way to get an icy sample, we intend to proceed with analyzing dry samples that we already know how to deliver," said Phoenix principal investigator Peter Smith, of the University of Arizona.

Phoenix mission controllers have been scraping up samples from the subsurface rock- hard ice layer and testing out methods to deliver an icy sample to TEGA since mid-July. TEGA heats up the samples and then analyzes the vapors they give off to determine the sample's composition.

More at www.space.com