This mission will spend several years studying the icy Galilean moons Europa, Callisto, and Ganymede in an attempt to better understand their formation, structure, and evolution.

67 moons orbit the great gas giant Jupiter; of these, the four largest are known as the Galilean moons, having been discovered by Galileo Galilei using his telescope in 1610. The four moons are Io ...

The moons of Jupiter. As mentioned last week, current count has them at 79, though only 53 have been officially named. The majority of these moons are fairly tiny, which is why it’s difficult to ...

Jupiter's big ocean-harboring moons may have a strong gravitational effect on each other, raising big tides in each others' subsurface seas, a new study suggests.

Growing moons. In general, researchers agree that the four Galilean moons — Io, Europa, Ganymede and Callisto — probably formed from a disk of gas that surrounded Jupiter in its infancy.

The Galilean moons are much brighter than the others. It took 282 years of telescope advancements for the fifth moon, Amalthea, to be discovered. Galileo’s scope was indeed primitive.

Saturn may have played a key role in the birth of Jupiter's largest moons, a new study finds. This discovery may shed light on whether potentially habitable giant moons could form around alien ...

The two Galilean moons of Io and Europa (left to right) can also be seen. (CORBIS/Corbis via Getty Images) On Jan. 7, 1610, Galileo discovered four moons revolving around Jupiter — a discovery ...

Jupiter presented a stunning gift last weekend, at least to those who had a clear view from Earth. On Aug. 15, Jupiter’s largest moons, known as the Galilean moons, aligned to give two stunning ...

The moons’ extremely thin atmospheres make their red auroras shine far more intensely than their green ones do. Io, the oddest Galilean satellite, has a streetlamp-like yellow-orange radiance.

The moons of Jupiter. As mentioned last week, current count has them at 79, though only 53 have been officially named. The majority of these moons are fairly tiny, which is why it’s difficult to ...