Possible signs of life on Mars? The Curiosity rover finds ‘tantalizing” organic matter from the red planet
NASA’s Curiosity rover has found some interesting organic compounds on the red planet that could be signs of ancient life on Mars, but much more needs to be done to test that hypothesis.
The powdery stone samples that Curiosity has collected over the years contain a type of carbon-rich organic compound that is involved in life here on Earth, researchers report in a new study.
But Mars is very different from our Earth and the process of many Mars remains a mystery. So too soon to find out what the disturbing chemicals created, the research team members insisted.
“We are finding something very interesting on Mars, but we will need more evidence to say that we have identified life,” said Paul Mahafi, who served as chief investigator at Curiosity’s Sample Analysis Chemistry Laboratory on Mars (SAM) until his retirement. Did. From NASA’s Goddard Space Flight Center in Greenbelt, Maryland in December 2021, it said in a statement. “So we’re seeing the carbon signature we’re seeing, what could happen if not life.”
Almost a decade of sample analysis
Curiosity landed on a 96-mile-wide (154-kilometer) gale crater inside Mars in August 2012 on a mission to determine if the area supported microbial life. The rover team soon determined that Gail’s soil was a potential habitable environment billions of years ago, hosting a system of lakes and streams that probably continued for millions of years at a time.
In a new study published Tuesday (January 18) in the proceedings of the National Academy of Sciences, the research team analyzed two dozen powdery rock samples that Curiosity collected through its percussion drills at various locations between August 2012 and July 2021. Rover introduced this material to SAM, which Organic compounds can detect and identify carbon-containing molecules that are the building blocks of life on Earth.
Scientists have found that about half of this sample is rich in carbon-12, which is lighter than the two stable isotopes of carbon compared to previous measurements from the Martian meteorite and the Martian atmosphere. (Isotopes are versions of an element that contains a large number of neutrons in their atomic nucleus. Carbon-12 has six neutrons, and much less abundant carbon-13 has seven.)
These carbon-12-rich specimens come from five different locations in the Gal Crater, each with features of ancient surfaces that have been preserved for centuries.
On Earth, organisms prefer carbon 12 for their metabolic processes, so the enrichment of these isotopes in ancient rock specimens is generally interpreted as a sign of biochemistry. But the carbon cycle on Mars is not understood enough to make similar assumptions for the red planet’s results, say research team members.
Researchers have suggested three possible explanations for the attractive carbon signal. The first involves a bacterium that produces methane from Mars, which is converted into more complex organic molecules after interacting with ultraviolet (UV) light in the red planet’s air. These larger organic compounds then fell to the ground and merged into the specified rocks of Curiosity.
But similar reactions involving ultraviolet rays and non-organic carbon dioxide, the most abundant gas in Mars’ atmosphere, could also produce results. It is also possible that the solar system passed through a huge molecular cloud rich in carbon-12 long ago, the researchers said.
“All three interpretations match the data,” said research leader Christopher House, a Pennsylvania State University-based curiosity scientist in the same statement. “We need more data to cancel these.”