New Mars Fossil Study Confirms the Ancient Red Planet Was 'Hospitable' to Alien Life
Earlier this month, we reported that acidic streams in a small region of Dorset, UK, could give astrobiologists a template for how to find microbe fossils in Mars' dried-up stream beds. Now, a full-blown "Field Guide to Finding Fossils on Mars" has been published in the Journal of Geophysical Research, outlining the best places to look for fossilized traces of life on the Martian surface.
The new study sums up the paradox of Mars quite nicely: "There is no compelling evidence for life on Mars, now or in the geological past. However, there is now a very strong case that the surface of early Mars was habitable."
Claims of alien cannon balls aside, no rover or satellite has found direct evidence of life on the Martian surface, though there is significant evidence that the planet had oceans and rivers of liquid water.
A lot of brainpower and resources have gone into the examination of these waterways, but that may be the problem with our search—maybe the important water was below Mars' surface all along.
According to the study:
"The Martian surface has been cold and predominantly dry for at least the last three billion years (i.e., the Amazonian Period, immediately following the Hesperian), but the subsurface could have sustained stable reservoirs of geothermally heated liquid water for much of this time, representing a long-lived habitat that could have exchanged living cells with shorter-lived habitats at the surface...Once established, however, a"deep biosphere"would have been protected from the deteriorating conditions at the surface and able to persist far longer given indigenous sources of energy and nutrients."
All of this is assuming that whatever life survives on Mars was predominantly microscopic—no alien civilization, not bug-eyed greys, just extraterrestrial bacteria.
With this in mind, the study says some of the best places to look for fossilized microbes would be basaltic rocks, silicas, and certain types of sediments either on Mars' surface or below it.
Luckily for us, NASA's InSight mission is already gearing up to do exactly that.