It's easy for Hubble to take pictures of Jupiter or its moons, but it only gets the chance to capture the planet on cam with three visible Galilean satellites once or twice a decade. That's what makes the photo above special: it's a picture of the gas giant with three of its largest moons (and their shadows) making their way across the surface. Hubble used its Wide Field Camera 3 to take several photos of the event on January 23rd, 2015 -- the still you see above shows how the moons were positioned by the end of the 40-minute period.