"The Curiosity rover has been sampling on Mars for the past 5 years. Eigenbrode et al. used two instruments in the SAM (Sample Analysis at Mars) suite to catch traces of complex organics preserved in 3-billion-year-old sediments. Heating the sediments released an array of organics and volatiles reminiscent of organic-rich sedimentary rock found on Earth. Most methane on Earth is produced by biological sources, but numerous abiotic processes have been proposed to explain martian methane. Webster et al. report atmospheric measurements of methane covering 3 martian years and found that the background level varies with the local seasons. The seasonal variation provides an important clue for determining the origin of martian methane.
Science, this issue p. 1096, p. 1093; see also p. 1068"
Organic compounds... hmmm... does that mean there might have once been a Whole Foods there?
They won't say it because they are good scientists and their reputations are on the line. But I'll go ahead and say it ... it's really starting to look like there's something alive on Mars.
I have to say that I agree with the scientists here. Saying that there is clear evidence of past or present life on Mars is premature.
This is not my area of science... but based on what I am hearing, there are three possibilities. First, it is very possible that these molecules have a source that is not biological... meteoric activity for example. Second, it is possible that the origin of the organic molecules was biological, but that the life that caused them is now extinct. The periodic methane (from what I have heard) could be cycling through some environmental process.
And Third.... Of course, it is possible that something is living under the surface. It is hard to say what fits the data when we don't have all the data yet.
Sorry to be a downer. It is just that I share the caution of the scientists.
I have personally always considered it a given that tiny life once existed on Mars.
But the possibility says the government should keep human feet away from there, until they asses the impact it would make.