Curiosity rover's 'selfie' at John Klein drilling site taken on 3 February 2013. Image via NASA/JPL-Caltech/MSSS
The discovery of nitrates in Martian rocks shows promise regarding the previous existence of life on Mars, according to samples collected by US space agency NASA’s Curiosity rover.
The nitrogen compounds discovered in the samples are important for discovering the history of the red planet as the element is present in the birth of the three factors which give birth to protein: DNA, RNA and amino acids.
The team from NASA’s Goddard Space Flight Center, which included Jennifer Stern, a planetary geochemist, examined three different samples that covered varied locations on the planet’s surface including aeolian deposits from Rocknest and mudstone deposits from John Klein and Cumberland, according to Phys.org.
When the samples were super-heated in Curiosity’s Sample Analysis at Mars (SAM) analyser, the samples were shown to have as much nitrate as would be comparable with some of the driest places on Earth, which is understandably a good sign.
A successful detour
Until now, much of NASA’s research into the possible previous existence of life on Mars has revolved around the search for carbon which would indicate the remains of a former example of life, but nitrogen, the team say, is just as important in establishing whether the planet was once a lot greener.
The discovery of these samples was actually down to an executive decision by Curiosity’s handlers to go on a risky three-day detour to climb Mount Sharp located in the centre of the enormous Gale crater which, the team believed, could be home to former evidence of life due to its large deposits of clay-like material.
However, the team are still looking at the more likely reasons as to how nitrates exist within the Martian rock which they say could be down to them having been caused by a ‘thermal shock’, most commonly seen during a meteorite impact or lightning.
Speaking of the mission’s next step, Jennifer Stern said, “We’re going to try to understand whether this process is still happening today at all, or whether this all happened in the past in a different Mars, in a different climate regime, in a different atmosphere.”
