Glass formed by the searing-hot impact of an asteroid or other celestial body could hold clues toward past life on Mars. 

Two planetary science researchers at Brown University have found glass in impact craters on Mars by looking at satellite data, as they describe in an article in the journal Geology. Geologists have found that glass in similar craters on Earth holds excellently preserved evidence of life in ancient times, including tiny leaf fragments trapped inside, indicating that impact craters might be a viable target in the search for life on other planets.

The glass deposits detected by the satellites may provide “a means to trap signs of ancient life on the accessible martian surface,” the researchers write. To find glass on a planet 140 million miles away, they measured the spectrum of light bouncing off the planet’s surface using a spectrometer on NASA's Mars Reconnaissance Orbiter. Much of the glass they found is located near crater peaks, suggesting that the glass did come from an impact. Glass is shown in green in the image above.

Mapping out locations rife with this impact glass helps scientists determine where they should be exploring on Mars, and where they might need to send a rover to collect a sample that might hold ancient alien life. 

[h/t: Eurekalert]