As promised, NASA has announced new milestone Mars discoveries, namely the presence of organic molecules and seasonal changes in atmospheric methane. The findings add to the body of evidence suggesting Mars may once have been able to sustain life. Both discoveries were made possible by NASA’s Mars Curiosity rover and have been detailed in a pair of new studies.
NASA announced the discoveries in a livestream this afternoon, saying Curiosity found the latest evidence for ancient life on Mars in rocks. According to the space agency, Curiosity rover discovered organic molecules after drilling mudstone, a type of sedimentary rock, in a handful of places in the Gale Crater.
Researchers previously determined that the Gale Crater likely contained a water lake billions of years ago that had the basic, vital ingredients for life. This latest discovery adds evidence that Mars may have been capable of supporting life in its ancient past, though there’s still no evidence that life had actually existed on the Red Planet.
In addition to organic chemicals, NASA revealed that Curiosity discovered seasonal atmospheric methane variations on the Red Planet. The changes were detected by the rover’s Sample Analysis at Mars instrument suite, more commonly called SAM. The changes were observed over three Martian years, which are equivalent to nearly half a dozen Earth years.
Researchers had previously revealed the discovery of methane in the Martian atmosphere, and this latest discovery builds upon that via season-based variations. Specifically, NASA says that lower levels of methane were found to decrease in the winter and peak in the summer on an annual basis. NASA JPL’s Chris Webster explains the significance of that finding, saying:
This is the first time we’ve seen something repeatable in the methane story, so it offers us a handle in understanding it. This is all possible because of Curiosity’s longevity. The long duration has allowed us to see the patterns in this seasonable ‘breathing.’