VIDEO: Hubble’s Hat Trick

The space telescope captures three moons crossing the disk of Jupiter at the same time.

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Hubble view of Jupiter moons transiting the planets surface on January 24, 2015.

Astronomers routinely see the moons of other planets crossing in front of the worlds they orbit.  But only once or twice a decade do they see three of Jupiter’s largest moons—Europa, Callisto and Io—“transiting” at the same time.  The Hubble Space Telescope captured such a view on January 24—and caught a couple of smaller moons in the process. Click here for a larger version of the image.