The Spirit rover’s first detailed look at the soil of Mars show it to be a complex jumble of surface materials, akin to that found at the Viking and Mars Pathfinder landing sites.Using Spirit-deployed science gear to study a select patch of Mars at Gusev Crater, silicon, sulfur, chlorine, calcium, iron, and nickel have been detected. One mineral, Olivine has also been found. That finding would seemingly cast doubt on the prevalence of water as a geological agent at Gusev Crater. Olivine is a suite of iron-magnesium silicate minerals known to crystallize, first from a magma, and subject to weathering in the presence of water. The occurrence of olivine on the surface of Mars and its weakness to chemical weathering has science teams pondering over how long that material has been there and about the prospect of a watery history at Gusev Crater.Spirit’s landing zone is thought to be a crater lake at one time and should be filled with sediments deposited in the lake. But at what depth those sediments now reside remains arguable.

"It’s going to take a long time to puzzle through this…but the key is we’ve got the tools to do it," said Steve Squyres, Principal Investigator for the Mars Exploration Rover project.


View: Full Article | Source: space.com