NASA's Mars Reconnaissance Orbiter has found glass in a crater on Mars.
No, it's not the leftovers from an ancient Mars cocktail party where rowdy guests smashed "marstini" glasses on the ground. It's a type of glass known as impact glass, which is formed from the heat of a meteorite impact. Because the material that's around when the meteorite hits can be sealed in the glass, NASA researchers believe the glass could provide a clue to possible past life on Mars.
That's especially true because some of the impact glass the MRO found was in a crater called Hargraves that's situated near a 400-mile-long (about 650 kilometers) trough known as Nili Fossae. That area is rich in hydrothermal fractures, which are vents that might have sustained life just below the Martian surface.
"If you had an impact that dug in and sampled that subsurface environment, it's possible that some of it might be preserved in a glassy component," Brown University researcher John Mustard said in a statement. "That makes this a pretty compelling place to go look around, and possibly return a sample."
Mustard worked with Brown graduate student Kevin Cannon to find the glass. The duo built on previous research from Peter Shultz (also of Brown) that showed plant matter and other organic molecules in impact glass found in Argentina from a meteorite collision millions of years ago.
"The work done by Pete and others showed us that glasses are potentially important for preserving biosignatures," Cannon said. "Knowing that, we wanted to go look for them on Mars and that's what we did here. Before this paper, no one had been able to definitively detect them on the surface." The paper Cannon is referring to was published last week in the journal Geology.
Seeing the glass in images from the MRO proved to be quite a challenge because -- believe it or not -- the glass doesn't give off as strong a signal as the rock that's mixed with it when light is reflected off the Martian surface.
To tease it out, Mustard and Cannon re-created a bit of Mars in the lab by firing powders similar to Martian rocks in an oven to create glass. Next they captured the light waves that glass reflected and created an algorithm to find similar signals in MRO's data. Their experiment was a success.
"This significant new detection of impact glass illustrates how we can continue to learn from the ongoing observations by this long-lived mission," said Richard Zurek, MRO project scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.
MRO has been orbiting Mars since its arrival on March 10, 2006, with the primary goal of figuring out whether water existed on the Red Planet for a long period of time in its history.