When the Hubble Telescope snapped this true-color image in April, NASA scientists found Jupiter staring right back at them. That black dot is Ganymede's shadow, crossing Jupiter's Great Red Spot, creating an eerily blank-looking eye. It is almost certainly the eye of a large and eternally amused monster (after all, Jupiter was, among other things, the "bringer of jollity").
The shadows of Jupiter's four major moons--Ganymede, Io, Europa, and Callisto--often cross its surface, the Hubble team reports. So this image is actually not so rare, just well-aligned. Ganymede is the solar system's largest moon, so its shadow is especially impressive.
For another example of unintentionally spooky stuff in space, check out this image of the sun that NASA captured earlier this month.
