Become a Member


News Archive



2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017

Thursday, May 3, 2007



Patchy Water

Mars is shown by false colors in this map made using THEMIS temperature measurements. Blue shows where ice would be 5 centimeters (2 inches) deep, while red shows an ice depth of more than 18 centimeters (7 inches).
Mars is shown by false colors in this map made using THEMIS temperature measurements. Blue shows where ice would be 5 centimeters (2 inches) deep, while red shows an ice depth of more than 18 centimeters (7 inches).
Credit: NASA/JPL/Arizona State University
Scientist at Arizona State University have found ice at variable depths on Mars. "Scientists have known for more than a decade that water is on Mars, mostly in the form of ice," says Philip Christensen of ASU's Mars Space Flight Facility. Christensen, a Regents' Professor of geological sciences at ASU, designed THEMIS but did not participate in this research. "What's exciting is finding out where the ice is in detail and how it got there. We've reached the next level of sophistication in our questions. ... [Gamma Ray Spectrometer] can probe a meter deep, but it has a giant footprint [~500km]. Most infrared spectrometers can detect surface ice and ice a few fractions of a millimeter down. THEMIS is sensitive to thermal waves which can penetrate several inches deep - and it can spot details the size of a football field."

Joshua Bandfield, a research specialist in Arizona State University's School of Earth and Space Exploration and sole author of the paper, explains, "pump a lot of heat into the ground and increase the depth where you'll find stable ice." In contrast, he says, dusty areas tend to insulate the ice, allowing it to survive closer to the surface. "These two surface materials - rock and dust - vary widely across the ground, giving underground ice a patchy distribution." Bandfield adds "[t]he take-home message for the Phoenix lander is that the THEMIS results show a lot of patchiness in the ground ice, and this should continue down to smaller and smaller scales." "Phoenix", he adds, "may find ground ice is shallower and much easier to reach in some spots than in others."

THEMIS @ ASU


- posted by Jim @ 9:05 EST