Jupiter
King of the planets
Jupiter is a gas giant more than twice as massive as all the other planets combined. Its atmosphere is stratified into colorful bands, and its most famous feature is the Great Red Spot, a storm that has raged for centuries.
Key facts
- Diameter
- 139,820 km
- Radius
- 69,911 km
- Mass
- 1.898e+27 kg
- Gravity (Earth = 1)
- 2.360
- Density
- 1.326 g/cm³
- Distance from Sun
- 778,500,000 km
- Orbital period
- 4,331 Earth days
- Rotation period
- 9.93 hours
- Average temperature
- -110°C
- Known moons
- 95
Values are approximate and based on cited sources.
Atmosphere
- Hydrogen
- Helium
- Methane
- Ammonia
Surface
No solid surface; a deep atmosphere transitions to liquid metallic hydrogen at extreme pressures.
Internal structure
A likely diluted rocky core, a layer of metallic hydrogen, and a thick molecular hydrogen envelope.
Moons
Io
Hundreds of active volcanoes powered by tidal heating.
Europa
Considered one of the most promising places to search for life beyond Earth.
Ganymede
The only moon known to generate its own magnetic field.
Callisto
Its ancient surface preserves a record of billions of years of impacts.
Exploration missions
- • Voyager 1 and 2
- • Galileo
- • Juno
Sources
- NASA Science — Jupiter— last verified 2026-01-15