080630 Phoenix soil could support life

Top Stories

		Twin galaxies in cosmic arm wrestle ...astronomers at the Gemini Observatory have captured the early stages of gravitational interaction between two similar galaxies as they tug on each other’s spiral arms.... read more Massive impact on Mars supported by computer simulations ...the dramatic differences between the topography of the northern and southern hemispheres of Mars could finally be supported by computer simulations of a planet sculpting collision.... read more One hundred not out ...the impact event that rocked the unsuspecting Siberian outback 100 years ago today may hold the secrets to the protection of our precious blue planet against a similar cosmic assault in the future. .... read more

Spaceflight Now +

		Subscribe to Spaceflight Now Plus for access to our extensive video collections! How do I sign up? Video archive STS-120 day 2 highlights Flight Day 2 of Discovery's mission focused on heat shield inspections. This movie shows the day's highlights. Play STS-120 day 1 highlights The highlights from shuttle Discovery's launch day are packaged into this movie. Play STS-118: Highlights The STS-118 crew, including Barbara Morgan, narrates its mission highlights film and answers questions in this post-flight presentation. Full presentation Mission film STS-120: Rollout to pad Space shuttle Discovery rolls out of the Vehicle Assembly Building and travels to launch pad 39A for its STS-120 mission. Play Dawn leaves Earth NASA's Dawn space probe launches aboard a Delta 2-Heavy rocket from Cape Canaveral to explore two worlds in the asteroid belt. Full coverage Dawn: Launch preview These briefings preview the launch and science objectives of NASA's Dawn asteroid orbiter. Launch \| Science Become a subscriber More video

Phoenix soil could support life
BY DR EMILY BALDWIN
ASTRONOMY NOW
Posted: June 30, 2008

The results of the first ‘wet chemistry’ experiments on Mars soil were returned to Earth last week, revealing conditions that could support life as we know it.

Close up view of fine grained 'fluffy' soil sitting on the Robotic Arm scoop. Scientists have named this sample 'Rosy Red', which was dug from the Snow White trench. Some of this sample was delivered to the wet chemistry laboratory for analysis. Image: NASA/JPL-Caltech/University of Arizona/Max Planck Institute.

Scientists say that the Martian soil looks a lot like the kind of soil that can be found in the dry valleys of Antarctica on the Earth, and even shows evidence of water through the presence of salts.

"The alkalinity of the soil at this location is definitely striking," says Sam Kounaves of Tufts University. At this specific location, one inch into the surface layer, the soil is very basic, with a pH of between eight and nine. We also found a variety of components of salts that we haven't had time to analyse and identify yet, but that include magnesium, sodium, potassium and chloride."

"We also found a reasonable number of nutrients, or chemicals needed by life as we know it," he continues. "Over time, I've come to the conclusion that the amazing thing about Mars is not that it's an alien world, but that in many aspects, like mineralogy, it's very much like Earth."

The 'Wonderland' digging site which includes the Snow White trenches. Digging and scraping here proves that surface soil, subsurface soil and icy samples can all be taken from one unit. Image: NASA/JPL-Caltech/University of Arizona/Texas A&M University.

While the results of the wet chemistry tests continue to be analysed, the Thermal and Evolved Gas Analyser (TEGA) has baked its first soil sample to an impressive 1,000 degrees Celsius. Analysis of the gases released at a range of temperatures is a complicated procedure and will take weeks to process, but will ultimately identify the chemical make-up of the soil and ice that makes up the northern polar region of Mars.

Phoenix digging tools have also been busy in the last few days, sampling surface soil, subsurface soil and icy soil in a single trench. Onboard instruments will test samples to determine if some ice in the soil may have been liquid in the past during warmer climate cycles.