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© NASA/GSFC/Arizona State University
This image of the moon's surface was snapped by the Lunar Reconnaissance Orbiter's Wide Angle Camera with the sun directly overhead. Under these conditions, surface features show no shadows, causing an increase in brightness in the image called an "opposition surge".

The camera uses different filters to observe different pieces of the ground at different times. Here, the 689, 643, and 604 nanometre filters are displayed in red, green, and blue, respectively.

Because the opposition surge is seen by different filters at different times, when the observations from separate filters are combined to a single colour image, the shifting bright spot is seen as a rainbow, inadvertently recreating Pink Floyd's "Dark Side of the Moon".

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