A spacecraft orbiting Mars has spotted glass in the red planet's impact craters. And it's possible that this glass, formed in the searing heat of ancient impacts, could contain signs of long-ago life.
The latest findings from NASA's Mars Reconnaissance Orbiter (MRO), published in the journal Geology, suggest that glass may actually be a pretty common feature on Mars. On Earth, scientists have found that impact glass can contain ancient organic molecules that were present during the collision. If the same is true on Mars, it could mean treasure troves that have stayed locked away since the days when Mars hosted some form of life. If there were ever microbes thriving on the alien world, they may still be buried in some of this impact glass.
This is the first time such glass has been detected on Mars. The way to find it is to look for its signature reflectiveness when measuring the light that bounces off the planet. But impact glass has a fairly low light signal, and it's usually drowned out by the rocks sitting around it. To tease out the glass itself, researchers had to figure out what its spectral signal would be in a lab experiment, then create an algorithm to go looking for that signal specifically amid all the data noise produced by the rocky planet.
“The researchers’ analysis suggests glass deposits are relatively common impact features on Mars,” said Jim Green, director of NASA’s planetary science division, said in a statement. “These areas could be targets for future exploration as our robotic scientific explorers pave the way on the journey to Mars with humans in the 2030s.”
In fact, one of the craters thought to contain glass is quite near one of the proposed landing sites for the Mars 2020 mission, in which a new NASA rover will collect samples in the hopes of one day returning them to Earth. So it's possible we'll get a closer look at this tantalizing glass one day.