NASA's Curiosity rover has found new evidence preserved in rocks on Mars that suggests the planet could have supported ancient life, as well as new evidence in the Martian atmosphere that relates to the search for current life on the Red Planet.
While not direct evidence of life, the compounds drilled from Mars' Gale Crater are the most diverse array ever taken from the surface of the planet since the robotic vehicle landed in 2012, experts say. Understandably, the authors of the two papers, published in the journal Science, are very careful not to make the claim that they have discovered life on Mars.
At this point, there's simply no way of knowing whether the organic molecules and the methane findings point to potential life on Mars. Earth-based telescopes, spacecraft orbiting Mars and now Curiosity, have measured episodic sudden increases in the background methane content.
Although there is not enough information to know whether the carbon molecules were created by biological or non-biological processes, it is possible that they could be a source of methane, Dr Eigenbrode said.
The Curiosity rover, launched in 2011 with about $2.5 billion worth of scientific equipment with the intent of exploring and analyzing Mars' Gale Crater.
Curiosity's project scientist, Ashwin Vasavada of NASA's Jet Propulsion Laboratory in Pasadena, California, said: "The chances of being able to find signs of ancient life with future missions, if life ever was present, just went up".
Researchers said the findings correspond with findings of traces of methane, a chemical produced by some organic life forms, in the planet's atmosphere.
"We don't know, but these results tell us we are on the right track"'. If there was, then that life would have left behind organic molecules when it decayed. The Martian surface is bombarded with radiation that can degrade organic compounds, explains Eigenbrode. "And what it does, it gives us a key to unlocking the mysteries associated with Mars methane because now we have something to test our models and our understanding against".
"With these new findings, Mars is telling us to stay the course and keep searching for evidence of life", said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters.
Just a couple of weeks ago, NASA announced that Curiosity had successfully drilled a hole using this new technique, and its handlers were excited that the rover could get back to work.
Some of the new science instruments included on the next Mars rover include an X-ray spectrometer, ultraviolet laser, excited rings of carbon atoms, and a ground-penetrating radar that will allow the space agency to look under the surface of Mars up to 30 feet deep depending on terrain.
Three Mars years' worth of data shows that along with spikes in methane, levels swing between 0.24 and 0.65 parts per billion, peaking in the northern hemisphere summer. This mudstone gradually formed billions of years ago from silt that accumulated at the bottom of the ancient lake.
"We have no proof that the methane is formed biologically, but we can not rule it out, even with this new data set", Webster said. Hell comes from Mars, NASA, and it's only been two years since we cleaned up the last incident of Mars Hell. But they could also be the result of abiotic chemical reactions on the surface of the planet.