Europa, along with Jupiter's three other large moons, Io, Ganymede, and Callisto, was discovered by Galileo Galilei on 8 January 1610, and possibly independently by Simon Marius. On 7 January, Galileo had observed I… See more

Europa orbits Jupiter in just over three and a half days, with an orbital radius of about 670,900 km. With an orbital eccentricity of only 0.009, the orbit itself is nearly circular, and the orbital inclination relative to Jupiter's equatorial … See more

Europa is slightly smaller than the Earth's moon. At just over 3,100 kilometres (1,900 mi) in diameter, it is the sixth-largest moon and fifteenth-largest object in the Solar System. Though by a wide margin the least massive of … See more

Exploration of Europa began with the Jupiter flybys of Pioneer 10 and 11 in 1973 and 1974, respectively. The first closeup photos were of low resolution compared to later missions. The two Voyager probes traveled thr… See more