as its Galilean moons show off while they dance in their orbits around the gas giant. Tonight, Europa and Ganymede transit Jupiter together, as they have a few other times this month. However ...

Following the discovery of the Galilean moons in January 1610 by means of a ... in California – the largest telescope in the world at the time. The moon, discovered by Barnard, orbits Jupiter within ...

But not all moons behave this way, and due to the complicated nature of some exoplanet orbits it’s now believed that many moons end up being flung from their homes and sent drifting into space.