NASA's Curiosity Rover discovered previously unknown organic molecules on Mars by using a new onboard experiment.
Although none of the organic molecules found in the sand are definitive signs of life, they do indicate that the new technique, which doesn't require the Rover to drill, can be used to search for evidence of carbon-based compounds, which are essential building blocks of life as we know.
Curiosity experienced a metaphorical bump in the road as it tried to find signs of life on Mars at the end of 2016, and the wet-lab experiment was born.
As the rover was about to sample the Martian rock near the base of Mt Sharp's summit, the drill stopped working.
NASA researchers changed their minds and put a halt to the mission until the problem was resolved.
Curiosity decided to not pulverize rock samples into powder. Instead, some loose sand from Ogunquit Beach was added into the 'wet chemical lab'.
The on-board laboratory contains only nine cups of solvent. Each sample can only be used once so researchers need to be very selective about the samples they choose.
Martian rock is full of organic compounds that can be difficult to identify because they become simpler when heated.
These organic compounds will react first with other chemicals, so they are more likely not to be broken down and enter a gaschromatograph or mass spectrometer. Curiosity has nine cups of solvent.
It is a cleverly designed system, which allows us to quickly analyze the soil on Mars from our planet. It was not tested until late 2016.
NASA's team didn't expect Ogunquit's sand to be organic rich. However, they weren't certain they could continue drilling on the planet moving forward so it was worth a shot.
Researchers broke the first seal on the Ogunquit Sand to find several organic compounds, including benzoic acid and ammonia. Some of these organic compounds were not previously identified on Mars.
The results were peer-reviewed and published a few years later.
These organic molecules are not a definitive sign that there was once life in Mars. No amino-acid derivatives were found in the sample.
What's even more exciting is the fact that you can use this technique to search for signs of life even if you don't have the ability to drill.
"This Mars derivatization experiment has increased the inventory of molecules in Martian samples and showed a powerful tool for further enable the search to find polar organic molecules with biotic or prebiotic relevance," said the NASA research team led by Mava Millan, an astrobiologist from NASA's Goddard Space Flight Center.
It took more than a year for engineers to fix Curiosity’s drill and get it working again. But, by that time, we had figured out how the wet chemicals cups worked.
The second cup was ready for use to sample clay-bearing rocks from higher up Mt Sharp by 2019. More analyses will be done on Mars and Earth.
NASA intends to conduct a mission in 2030s to continue collecting the remaining Curiosity samples so they can be more thoroughly analyzed on our planet.
Nature Astronomy published the study.