Just like David Bowie, many astronomers keep wondering “Is there life on Mars?” Since the earliest exploration of the Red Planet, we have been trying to find signs of living organisms or at least evidence of past life, but as we have limited resources it’s good to know where to look. And a new study might now narrow the search a bit.
Published in Scientific Reports, the study suggests that if organic material is on Mars, it might not be able to survive meteorite impacts. According to the researchers from Imperial College London and the University of Edinburgh, only some of the organic material encased in rocks can survive such blasts.
The researchers simulated an impact from a meteorite of around 10 meters (33 feet) in size and looked at what type of organic compound could withstand the extreme conditions of a blast. Long hydrocarbon chains found in microbes would be destroyed, but molecules known as aromatic hydrocarbons (often found in plant matter) would survive the impact.
The study also suggests that the organic material present on meteorites, which is not created by living organisms, could survive the blast.
"The study is helping us to see that when organic matter is observed on Mars, no matter where, it must be considered whether the sample could have been affected by the pressures associated with blast impacts,” co-author Dr Wren Montgomery said in a statement. “We still need to do more work to understand what factors may play an important role in protecting organic compounds from these blast impacts. However, we think some of the factors may include the depths at which the rock records are buried and the angles at which meteorites hit the Martian surface."
Drilling on Mars is expensive and limited by how deep a probe or rover can physically reach. Using blast sites has been seen as a convenient alternative to study deeper rocks that might not have been exposed otherwise. But this research has shown that blast sites have also got drawbacks.
The study, though, can help future missions to the Red Planet by suggesting the best locations to land, and even what type of blast rocks could be hiding the long-sought piece of evidence that Mars used to host life.
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