Samples collected from the Curiosity Rover’s mission on Mars reveals evidence of nitrates, lending additional credence to the theory that the red planet once hosted habitable environments.
Nitrates are the molecules that make it easier for living things to access Nitrogen from the Earth’s atmosphere, a key component of amino acids and other biomolecules. Scientists are now saying that they have found evidence of the molecules in samples collected from Mars’ sedimentary rock during the Curiosity Rover mission.
The findings were published in the journal, Proceedings of the National Academy of Sciences, and support the idea that the red planet, which is now dry and barren, was once hospitable to life.
“People want to follow the carbon, but in many ways nitrogen is just as important a nutrient for life,” lead author and planetary geochemist at NASA Goddard Space Flight Center Jennifer Stern said. “Life runs on nitrogen as much as it runs on carbon.”
The samples were collected by the Curiosity Rover from three different sites on Mars, all of which were part of a detour from the Rover’s main mission, one that apparently proved extremely fruitful for NASA scientists. Samples were collected from aeolian deposits from the Rocknest site, and mudstone deposits from the John Klein and Cumberland sites, before they were stored and processed by the Sample Analysis at Mars (SAM) instrument in Curiosity.
The rocks were cooked in SAM’s oven and scientists analyzed the resulting gases. In studying the samples, scientists had to carefully subtract that amount of contamination from the Rover itself. What they found was a significant amount of nitric oxide, which they believe came from nitrates before the rocks were heated and cooked.
“What we’re detecting is a nitrate oxide,” Stern said. “But we know from lab experiments when we heat up nitrates, they break down in a predictable way, and that’s why we think these are nitrates.”
The scientists found enough nitrogen in the samples to account for an amount of nitrates equivalent to that present in extremely dry places on Earth, such as the Atacama Desert in South America.
While nitrates are usually produced by living things on Earth, Stern said that in the case of Mars, her team believes they were created during a “thermal shock”, such as a lightning strike or an asteroid impact.
“We’re going to try to understand whether this process is still happening today at all,” She said, outlining the team’s next steps. “Or whether this all happened in the past in a different Mars, in a different climate regime, in a different atmosphere.”
NASA scientists reveal new compelling evidence that proves the red planet once hosted a massive body of water, at least the size of the Arctic Ocean.
The evidence unveiled by NASA scientists lends credence to the idea that Mars may be a more promising place for the emergence of alien life than previously believed. It additionally supports the theory that the planet was a warm and wet world in its youth, soon after it formed around 4.5 billion years ago.
The body of water, according to findings obtained after six years of planetary observation, covered over a fifth of Mars’s surface, equivalent to the portion of Earth covered by the Atlantic Ocean. The ocean was over a mile deep in places and held an impressive 20 million cubic km of water, more than the Arctic Ocean.
The findings were revealed in the journal, Science, and were a result of a collaborative study between NASA scientists and others at the European Southern Observatory in Munich. “A major question has been how much water did Mars actually have when it was young and how much did it lose.” Michael Mumma, a principal investigator at NASA’S Goddard Center for Astrobiology said. “Our results tells us there had to be a northern ocean.”
The scientists addressed this question by using three of the most powerful infrared telescopes in the world — located in Hawaii and in Chile — to track changes to the Martian atmosphere over six years and specifically look at how different forms of water molecules in the Martian air varied in different places through changing seasons.
Scientists found that Martian water contained standard H20 water molecules, as well as a form of water made of a heavier hydrogen isotope called deuterium. They speculate that as the Martian atmosphere thinned over time, the water containing lighter molecules wafted into space, leaving behind a higher concentration of deuterium. It is also estimated that the planet had lost a massive amount of water, roughly six times than currently locked up in the its frozen ice caps.
The findings allow scientists to re-write the once strongly held belief that flowing water on the planet was only an erratic presence.
Other experts, like Curiosity rover project scientist Ashwin Vasavada, remain skeptical of the results, stating that the idea of a Mars ocean is still simply “hypothetical.” Geronima Villanueva, the study’s first author and another planetary scientist, is convinced the findings are enough to support the theory.
“Ultimately,” He said. “We can conclude this idea of an ocean covering 20% of the planet which opens the idea of habitability and the evolution of life on the planet.”