Scientists using the Curiosity rover’s Sample Analysis at Mars (SAM) instrument have found complex organic molecules on Mars when analyzing samples from a mudstone in the site dubbed ‘Yellowknife Bay.’ The findings are the first results from the wet chemistry experiment on SAM, and were presented at the 46th Lunar and Planetary Science Conference (LPSC).

The wet chemistry experiment was designed to detect refractory organics. These molecules are bigger and more polar than other organic molecules, and can’t be analyzed by simple heating (e.g. pyrolysis) of a sample. After arriving at Mars, vapor from a chemical used in the experiment (known as MTBSTFA or N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide) leaked into the system. Due to the leak, researchers had to find a way to carefully exclude MTBSTFA from results obtained in the pyrolysis experiments.

However, the MTBSTFA leak has also presented an opportunity for some unique science because researchers can study how the chemical reacts with refractory components in Mars samples. The preliminary results presented at LPSC are promising, and future work will help rule out contamination as a possible source of the complex organic molecules that were found.

Finding complex organic molecules native to Mars is an important step in determining the habitability of ancient Mars.

The abstract, “First in situ wet chemistry experiment on Mars using the SAM instrument: MTBSTFA derivatization on a Martian mudstone,” is available as a pdf at: http://www.hou.usra.edu/meetings/lpsc2015/pdf/2934.pdf

Development of instruments on the Curiosity rover, including Sample Analysis at Mars (SAM) and Chemistry & Mineralogy (CheMin), was supported by the ASTID element of the NASA Astrobiology Program.