Martian 'ice cauldrons' are prime spot to hunt LGMs, say boffins
But only if there's water there, which other boffins doubt
One of the reasons it's so hard to find life on Mars is that hardly anwyhere we've spotted on the red planet combines liquid water and survivable temperatures.
Now a study from the University of Texas (UT) suggests such a place may exist, because it once had enough volcanic activity to produce the right conditions.
The location is in the Hellas basin, and when UT research associate Joseph Levy first noticed it in 2009, he noticed similarities to features on Earth, but needed a second study to confirm his suspicions.
As the university's announcement says, Levy first spotted tracks on Mars Reconnaissance Orbiter images that looked like “ice cauldrons” on Earth. Such features are known from places in Iceland and Greenland where volcanoes erupt under ice sheets.
Confirmation of what the boffins were looking at had to wait until Levy could re-examine the Martian locale using stereo images put together by collaborator Timothy Goudge. Goudge used pairs of high-resolution images to create a digital elevation model (DEM) of the region.
The DEM revealed a deep funnel structure – similar to ice cauldrons.
The Hellas depression (left) looks more like an ice cauldron than the Galaxias Fossae depression (right). Image: Joseph Levy and NASA
Levy adds that with the DEM the pair could “measure not just their shape and appearance, but also how much material was lost to form the depression”, something he says helps differentiate between volcanic activity or comet impact.
Between 1,000 and 100,000 cubic metres of magma would be needed to melt the amount of ice Levy spotted (big error bars, but there's nobody to take measurements on the ground).
A nearby depression in the Galaxias Fossae region provided a handy comparison: while it looked similar, it had nearby debris indicating an impact (which the Hellas depression lacked), while Hellas also has a “fracture pattern associated with concentrated removal of ice by melting or sublimation”.
Levy hopes that future Mars exploration missions can get the chance to check out the depressions, since the volcanic activity wouldn't just provide water and heat, it would also contain the kinds of chemical ingredients necessary for life.
The research is published in the solar system research publication Icarus (abstract here).
The only downside to the idea is that researchers from Stirling University in Scotland think Mars is far drier than current models suggest.
The researchers, led by the university's Dr Christian Schröder (who is also a collaborator on the Opportunity rover mission), looked at rust formation on Mars as their proxy for how much water is available on the surface. ®