Big Pic: The Solar System's Largest Moon, Mapped

A geological guide to Jupiter's moon Ganymede

Otherworldly

G. C. Collins and colleagues. USGS.

Fancy a trip to see Punt crater? This map will show you the way, though you're on your own for arranging transportation.

This is a map of Ganymede, one of the moons of Jupiter. With a diameter of more than 3,000 miles, Ganymede is three-quarters the size of Mars and the largest satellite in the solar system. This is the first moon-wide, geologic map of the moon. The map's different colors indicate different materials on Ganymede's surface. Those yellowish circles everywhere are craters, young (pale yellow) and old (dark yellow).

The data for this map came from NASA's Galileo orbiter and the Voyager 1 and Voyager 2 missions. It summarizes everything scientists know about the geology of this moon.

Check out the full map for more details about Ganymede's surface features. Or just enjoy this global view the U.S. Geological Survey prepared for NASA: