Jupiter's moon Ganymede was hit by an asteroid about 4 billion years ago that was so large the moon's axis shifted as a result, study finds.

Astronomers have observed 12 additional moons orbiting Jupiter, bringing its total number of confirmed moons to 92.

Jupiter's largest moon Ganymede, the main target of the JUICE mission, is also believed to possess an ocean, and so might the most distant, crater-riddled Callisto.

Jupiter already reigns as king of the planets — it's the largest one in our solar system. And now, the gas giant has the most known moons, too. Astronomers have observed 12 additional moons ...

The Jupiter Icy Moons Explorer, or JUICE, is a European Space Agency mission to explore Jupiter and three of its icy moons: Europa, Callisto and Ganymede.

Jupiter already reigns as king of the planets — it's the largest one in our solar system. And now, the gas giant has the most known moons, too. Astronomers have observed 12 additional moons ...

"We have been surveying for new moons around Jupiter serendipitously while our main survey is looking for planets in the outer solar system beyond Pluto," Sheppard said.

Jupiter already reigns as king of the planets — it's the largest one in our solar system. And now, the gas giant has the most known moons, too.