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Uploaded on Mar 5, 2011
NASA's Solar Dynamics Observatory caught the Moon slipping in front of the face of the Sun on March 4, 2011. This view is in the far ultraviolet and shows lots of solar activity like sunspots (which are bright in the UV) and prominences.
The Moon appears to change direction because SDO is orbiting the Earth. This is difficult to explain using just words, so I have created a diagram on my blog. It's the same effect that makes planets seem to reverse direction over several days (called "retrograde motion") or race cars seem to move left-to-right on the near side of the racetrack and right-to-left on the far side.