Cosmic Scale
Europa
Moon of Jupiter · 778 million km from the Sun
How big is Europa?
Europa is about 3,122 km across.
See Europa in 3D, at true scale
Beneath Europa's cracked shell of ice lies an ocean holding perhaps twice as much water as every ocean on Earth combined. Jupiter's tides keep it liquid, and the seafloor may be warm. It is one of the best places we know to look for life beyond Earth.
At a glance
| Diameter | 3,122 km |
|---|---|
| Mass | 4.80 × 10²² kg |
| Diameter compared with Earth | 0.245 × Earth |
| Orbits | Jupiter, every 3.5 days |
| Ice shell | 15–25 km thick |
| Ocean | 60–150 km deep |
| Discovered | 1610, Galileo |
Good to know
- Its surface is the smoothest of any solid body in the Solar System, and has very few craters — the ice is being resurfaced.
- NASA's Europa Clipper launched in October 2024 and will make dozens of close flybys from 2030.
- The reddish streaks may be salts from the ocean below, darkened by Jupiter's radiation.