What It Takes

Artemis III: Our Next Step Back to the Moon

Tiny Worlds Discovered by Hubble and Webb

There’s a Place on the Moon Where It’s 17°C

Shoot for the moon — so we can help the Earth #TEDTalks

As of September 2026, Jupiter officially has 115 known moons. It is a very diverse system: four of these moons — Io, Europa, Ganymede, and Callisto — were called the Galilean moons because they were discovered by Galileo Galilei in 1610. Io is the most volcanically active world in the Solar System: its interior is constantly heated by the powerful tidal interactions of Jupiter and the other moons. Europa is covered in an icy shell, likely harboring a global ocean of liquid water, making it one o