Normally we see the Earth from space as a gorgeous “blue marble”. Here it is, shown in an eerie grayscale, as seen from the Moon on June 12, 2010 — awe-inspiring yet with a different sheen. The picture was snapped by the Lunar Reconnaissance Orbiter (LRO) Cameras during a calibration sequence. The LRO has spent over a year on a mission to scout the moon. By imaging the bright Earth against the dark background of space, it’s possible to measure and correct for scattered light effects on the camera — which is important so that scientists can interpret color images from the camera properly.

In case you're wondering why the bottom of the Earth is clipped in this image, it's because the prediction of the exact time when the cameras' fields of view would cross the Earth was off by a few seconds. Nevertheless, it still makes for a spectacular view, don’t you think?

Thanks to the LRO Camera page for the image and information.