Mars is a strange place, whether we’re talking the seemingly nature-defying behavior of its liquids or just the tendency of even the most ordinary rock to have a secret life. But this latest look into one of its craters shows something odd even by Martian standards: There’s glass in there — and lots of it.
The Mars Reconnaissance Orbiter took a series of shots that showed some of the impact craters it had been looking at had large amounts of glass at the bottom. So where did it come from? Are Mars’ once-active volcanoes involved? Is it just really shiny, mirrored rocks? Perhaps evidence of an interstellar space collision? No to all of that, although the explanation is (almost) as fantastic — it’s impact glass, formed when super-heated debris slammed into the planet’s surface, creating a layer of glass that looks to go down fairly deep.
But even if they’re not signs of some lost alien spacecraft crash-landing on the planet, marooning the sole occupant with nothing to survive on but a collection of spaceship parts, his wits, and perhaps a friendly-looking volleyball upon which he can draw a face, they may still be telling us something about the possibility of life on Mars.
How? Well, we get impact glass here on Earth, too, and when it hits it pulls in and preserves the things around it (dust, plant life, signs of bacteria, whatever), a little like a time capsule would. If there was life when the impact glass on Mars was made, the signs of it could still be there, etched into the glass.
Of course, just knowing that it’s there isn’t enough to really figure out what’s going on; we’d need a sample and, with no rover within distance, we’re not getting one anytime right away. But give it five years, a rover visit is scheduled by NASA nearby for 2020 — we just might figure out what’s in the glass yet.
Image: NASA/JPL-Caltech/JHUAPL/Univ. of Arizona.