This is an exciting week for NASA’s Curiosity rover, which will perform a highly anticipated experiment that could reveal clues about the possibility of life once existing on Mars.
Curiosity frequently uses its Sample Analysis at Mars (SAM) instrument to analyze Martian samples including rocks and the atmosphere. However, this week SAM will be performing a very special investigation.
Within the SAM instrument are two small cups of a compound called tetramethylammonium hydroxide, or TMAH, which is used to identify organic materials in samples. It was only possible to fit a small amount of this compound into the rover, so it is a commodity that has to be used very carefully. Curiosity scientists have been waiting a long time for the right opportunity to use the TMAH and search for organic compounds.
“SAM contains only two small containers of TMAH and so we’ve been waiting for 8 years for just the right rock to drill to use this very precious expendable commodity,” NASA atmospheric scientist Scott Guzewich wrote in a blog post. “The wait is finally over and SAM will hopefully soon give us new insight into the chemistry of ancient Mars.”
Curiosity has recently been investigating a location called Mary Anning 3, where it has drilled a hole to access rock samples. This particular area of the Gale Crater is rich in clay minerals and could hold organic compounds, which can be associated with the presence of life but can be created by other processes as well. So finding organic compounds would indicate that the possible ingredients for life were once present on Mars, but it wouldn’t confirm that life definitely existed there.
To check for these organic compounds, Curiosity will run its drill backwards to drop samples of powdered rock into the SAM instrument where they’ll be soaked in TMAH. The gases given off can tell the researchers what kind of compounds make up the sample.
At the end of August, Curiosity performed a dry run of this experiment to make sure everything was working as expected and to ensure that the precious cup of TMAH wouldn’t be biased. Now, the instrument is ready to go ahead with the real experiment, and we’ll have to wait and see what results it finds.
