The discovery of organic molecules on Mars comes from a new technique used by NASA in 2017 when the Curiosity rover's drilling rig stopped working. However, the research team reoriented Curiosity to place soil samples in cups containing pre-made chemical mixtures instead of placing them in regular hollow bins.
These Martian soil models have traces of Benzoic and amoniac acids - both of which occur naturally in plants and animals, including humans.
The molecules discovered on Mars are not biological signs - that is, evidence of past or present life. However, post-doctoral fellow Dr Maëva Millan at NASA's Goddard Space Center said that these are good indicators of the presence of biological signs.
One of the things we are trying to understand when looking for organic molecules on Mars is understanding the possibility of life on Mars before and looking for biological indicators, she told Inverse.
The Curiosity rover landed on Mars on August 6, 2012 to investigate Mars' climate and geology as well as determine whether human cape has ever had life.
Five years after making landfall on Mars, the Curiosity rover collected soil samples from the Bagnold Dune area of Gale C study and the drilling rig stopped working.
To avoid wasting the samples, Millan and his colleagues have re-routed them. There are 74 cups in the Curiosity's belly used to hold soil samples, with 9 cups containing a chemical mixture.
Mars samples are often put into empty cups, but NASA is putting the samples in places where chemicals are available for the first time.
NASA researchers have not found evidence of life on Mars, such as amino acids. However, the results prove that those experiments are capable of detecting signs of life.
"Although we have not found what we are looking for, the biological traces, we do see that this technique is really promising," said Ms. Millan.
The conclusion of this new discovery was published in Nature Astronomy.
Like NASA's Mars Perseverance rover, Europe's upcoming Rosalind Franklin Mars rover will also search for life on Mars. The Rosalind Franklin spacecraft, due to launch in September 2022, will also use the experimental method that the Curiosity spacecraft has applied when searching for signs of ancient life on Mars. Europe's Mars rover is equipped with drilling equipment about 6.5m deep into the Martian surface for samples.
