What are the key features of Jupiter’s four Galilean moons?
Io – innermost of the 4 Galilean moons, 4th largest moon in the Solar System at 3642 km in diameter, over 400 active volcanoes, more than 100 mountains, some of which are larger than Mt. Everest, mostly made of silicate rock surrounding a molten iron or iron sulfide core. Europa – 2nd closest to Jupiter of the 4 Galilean moons and the smallest at 3121.6 km in diameter (slightly smaller than Earth’s Moon), one of the smoothest objects in the Solar System with a layer of water surrounding the mantle of the moon, thought to be 100 km thick. This leads to a possibility of extraterrestrial life. Few craters because the surface is tectonically active and strong. Primarily made of silicate rock and likely has an iron core. Tenuous atmosphere primarily composed of oxygen. Ganymede – Largest natural satellite in the Solar System at 5262.4 km in diameter, only satellite in the Solar System known to posses a magnetosphere likely created by convection within the liquid iron core. Composed primaril
