Hey, remember that one ton nuclear rover we sent to Mars? Yeah, that. On October 20, it aimed its megaWatt laser at the sand on Mars and blasted it 30 times in rapid succession, carving out a hole about 3 mm across. NASA kindly has provided a before-and-after animation of the damage inflicted on the Red Planet:
Cool, eh? [Click to coherentlightenate.] Curiosity's laser is designed not as a weapon against a hapless Marvin, but instead to do actual science. It very rapidly heats the rock (or sand or whatever) to the point where it vaporizes. Material heated like that glows, and in fact glows at very specific colors. By identifying those colors, scientists can determine precisely what the material is composed of. I gave the details in an earlier post when Curiosity zapped its first rock. You should read it, because spectroscopy is cool, and I spent many years ...
