Behold the First Geological Map of Ganymede, Jupiter’s Largest Moon
Four hundred years ago, Galileo Galilei observed Ganymede in orbit around Jupiter. This week, a team of planetary scientists unveiled the first global geological map of our solar system’s largest moon.
Using images obtained by NASA’s Voyager 1 and 2 spacecraft and the Galileo orbiter, a team led by Geoffrey Collins of Wheaton College pieced together a mosaic image of the planet, giving us our first complete image of the geological features of the satellite. Above, you can see the moon centered at 200 west longitude. The darker areas represent the very old and heavily cratered region of Ganymede, while the lighter areas are somewhat younger regions marked with grooves and ridges.