Jupiter's Galilean Moons

Four of Jupiter's inner-most satellites - the Galilean moons - are very easy to spot and their relatively short orbital periods make them entertaining to watch as they change position, eclipse each other and disappear and reappear from behind Jupiter itself. However they don't show up on the webcam videos unless they are over-exposed in which case Jupiter becomes a big blur. Hence a bit of artistic licence...


Here we have am over-exposed image of the moons overlaid on a processed image of Jupiter! From left to right we have Ganymede (the largest moon in the Solar System and even bigger than Mercury), Callisto (third largest in Solar System after Saturn's moon Titan) and Europa (sixth largest in the Solar System). Io (fourth largest in Solar System) is behind Jupiter so not visible. In case you were wondering, our moon is the fifth largest moon in the Solar System so sits between Io and Europa in size.