Editor's note: I wish I had a larger view of this one. I'll keep my eye out for one...
The terminator, the division between night and day, is not as obvious in this image as in some others, but it can be seen on the bottom left portion of the planet in this image. This bottom left edge of Mercury appears to fade away, in contrast to the sunlit limb of the bottom right edge. The terrain near the terminator is heavily shadowed, and some of the neighboring surface is in the darkness of Mercury's night.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
More about the MESSENGER mission to Mercury:
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