The MESSENGER spacecraft settled into orbit around Mercury earlier this month, and engineers have been busy making sure it's functioning well. Now, the first pictures are coming in from the solar system's innermost world, and as expected, wow!

Cooool! Or rather, hot. I mean, duh, it's Mercury. [Click to ensmallestplanetate.] The picture is dominated by the crater Debussy (named after the composer, who wrote "Clair de Lune", apropos of nothing, I suppose*), an impact crater about 80 kilometers (50 miles) across. It's a rayed crater, with plumes of ejecta leaving those long, linear features across the planet. This image is the first ever returned from a spacecraft orbiting Mercury, but MESSENGER has already taken hundreds more, and thousands are planned during this commissioning phase (when the various instruments and spacecraft are checked out). The real science observations begin April 4. Tomorrow, NASA will have a press conference and more images. I'll have more info and more amazing pictures from Mercury to show you then! Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

^* Oh, duh. After posting this article I realized he also wrote "Trois Scènes au Crépuscule". Why is that appropriate? Because Debussy is a rayed crater.

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