Ganymede is a moon, one of dozens circling Jupiter, yet it is larger than the planet Mercury. As the biggest natural satellite in the solar system, it stretches about 3,273 miles across, wider than a ...

Already high in the east as darkness falls, Jupiter still dominates the constellation Gemini. The gas giant’s large moon Ganymede transits the disk this evening, with its shadow following a few hours ...

The Hubble Space Telescope has spied evidence of water vapor in the atmosphere around Jupiter's moon Ganymede, the largest moon in our solar system. The water vapor forms as the icy surface of the ...

Add Yahoo as a preferred source to see more of our stories on Google. Jupiter's giant moon Ganymede is the only known moon to have its own magnetic field — and it may be heating up in a process "not ...

A new study suggests Ganymede—our neighborhood's biggest moon—still has a hot, churning core cranking out its unique magnetic field. Reading time 3 minutes Jupiter, the biggest planet in our solar ...

Add Yahoo as a preferred source to see more of our stories on Google. This natural-color image of Ganymede was captured by the Galileo spacecraft during its first flyby of the moon. (CREDIT: NASA/JPL) ...

Ganymede transits the face of Jupiter this morning, trailed by its large shadow. The event starts just before 4 A.M. EST, as Jupiter is slowly setting in the west for much of the U.S. (The planet is ...

The European Space Agency's (ESA's) Jupiter Icy Moons Explorer (JUICE) probe is on its (very long) way to Jupiter, and will finally arrive at the King of Planets in 2031. Its primary mission is to ...

Ganymede has long looked like a contradiction in orbit. Jupiter’s largest moon is the only moon known to generate its own magnetic field, a trait more commonly associated with planets like Earth and ...