In Depth | Ganymede – NASA Solar System Exploration
Jupiter’s moon Ganymede is proving to be a fascinating world. Not only is it the largest moon in our solar system, bigger than the planet Mercury and the dwarf planet Pluto, but NASA’s Hubble Space …
In Depth | Callisto – NASA Solar System Exploration
Callisto was discovered Jan. 7, 1610, by Italian scientist Galileo Galilei along with Jupiter’s three other largest moons: Ganymede, Europa and Io. Callisto is named for a woman turned into a bear by Zeus …
In Depth | Amalthea – NASA Solar System Exploration
Orbiting within Io's orbit, which is the innermost of the four largest moons of Jupiter (called the Galilean moons), are four smaller moons named Metis, Adrastea, Amalthea, and Thebe.
In Depth | Io – NASA Solar System Exploration
Jupiter's rocky moon Io is the most volcanically active world in the solar system, with hundreds of volcanoes, some erupting lava fountains dozens of miles (or kilometers) high.
Callisto - NASA Solar System Exploration
Jun 26, 2019 · As it approached Jupiter in June 2016, NASA's Juno spacecraft captured a movie of Jupiter’s largest moons circling the giant planet, marking the first time we could see the moons in orbit.
In Depth | Titan – NASA Solar System Exploration
Titan is bigger than Earth's moon, and larger than even the planet Mercury. This mammoth moon is the only moon in the solar system with a dense atmosphere, and it’s the only world besides Earth that …
Jupiter - NASA Solar System Exploration
Sep 3, 2025 · Before NASA’s Juno mission, three of Jupiter’s four largest moons, known as Galilean moons — Io, Europa, and Ganymede — were shown to produce these distinct auroral signatures. …
Europa By the Numbers – NASA Solar System Exploration
May 16, 2024 · Europa is one of the largest of Jupiter’s more than 90 moons. It's the sixth-closest moon to the planet.
In Depth | Europa – NASA Solar System Exploration
Jupiter’s large Galilean moons – Io, Europa, Ganymede, and Callisto – likely formed out of leftover material after Jupiter condensed from the initial cloud of gas and dust surrounding the sun, early in …
In Depth | Moons – NASA Solar System Exploration
Jupiter's menagerie of moons includes the largest in the solar system (Ganymede), an ocean moon (Europa) and a volcanic moon (Io). Many of Jupiter's outer moons have highly elliptical orbits and …