NASA Announces New Results That Could Suggest Life on Mars

On 7th June 2018, American space agency NASA announced a press conference to discuss two new results from the Curiosity rover, that has been on the planet Mars since 2012. In the conference, streamed live on the NASA website at 11:30 pm IST, it was announced that the rover had found new organic molecules on the surface and seasonal variations in the atmospheric methane levels, suggesting the presence of ancient life on the Red Planet.  While this is not concrete evidence of life, it strengthens the argument and could drive further expeditions to look for life and other geological activities on Mars. 

Back in 2014, Curiosity had found chlorinated molecules in a rock millions of years old, leading to the discovery of organic materials in Mars. Now, landing on a lake bed, it has detected a variety of organic compounds, ranging from ring-shaped (like benzene) to straight chained (like propene) molecules. This observation is ground-breaking because scientists speculate that these molecules could be part of a bigger macromolecule, like Kerogen. Lending support to this is the detection of thiophene. It has sulphur in its molecular structure, which can bind molecules to form large macromolecules and resist oxidation. Resisting oxidation was crucial to the discovery, as the rocks were ancient and any changes in the composition of these molecules would not lead to the development. All the evidence gathered points towards life because on Earth, Kerogen is a remnant of dead plants and algae. 

The molecular structure of Kerogen

But that’s not all that Curiosity uncovered. Uneven spikes of methane in the Martian atmosphere had perplexed scientists for years, until now. With the help of a suite of instruments called SAM (Sample Analysis at Mars), it was seen that the total amount of methane was constrained to 0.4 parts per billion. It also found out that the spikes were, in fact, dependant on the season of the year. This limited amount of methane was enough for the scientists to conclude that the gas was, in fact, seeping through the ground with the surface temperature playing a crucial role in its modulation.

Concentration of methane in Mars’ atmosphere in different seasons of the year

95% of all the methane on Earth’s atmosphere is made, directly or indirectly, by microbes. It is plausible that the methane in the atmosphere of Mars is generated by microbial activity.  So, while the answer to the eternal question of “Are we alone in the universe?” is still “maybe”, scientists believe that they are closer to the truth than ever before and our second closest neighbour might just have a more conclusive answer.

Image Credits: NASA