Gas giant
Jupiter
The giant planet
Jupiter is the fifth planet from the Sun and by far the largest in the solar system: more than twice as massive as all the other planets combined. It is a gas giant made mostly of hydrogen and helium with no solid surface. Its most famous feature, the Great Red Spot, is a storm larger than Earth that has raged for centuries. Jupiter's powerful gravity shapes the orbits of asteroids and comets throughout the solar system.
Quick facts
- Distance from Sun
- 778 million km (5.2 AU)
- Diameter
- 139,820 km (11x Earth)
- Day length
- 9.9 hours (fastest spin)
- Year length
- 11.9 Earth years
- Moons
- 95 confirmed
- Avg. temperature
- -110 C (cloud tops)
What's it like there?
There is nowhere to stand on Jupiter; descending into its clouds, pressure and temperature rise until hydrogen is squeezed into a strange liquid-metal state. The visible "surface" is bands of ammonia clouds racing in alternating directions at hundreds of kilometers per hour. Jupiter spins so fast that a full day lasts under 10 hours, flattening the planet visibly at its poles. Its radiation belts are the harshest of any planet.
Notable moons
Io
The most volcanically active world in the solar system.
Europa
An ice-covered moon hiding a global subsurface ocean; a top target in the search for life.
Ganymede
The largest moon in the solar system, bigger than Mercury.
Callisto
One of the most heavily cratered objects known.
Fun facts
Jupiter has the shortest day of any planet: under 10 hours.
The Great Red Spot is a storm at least 190 years old, possibly older than 350 years.
Jupiter has faint rings, discovered by Voyager 1 in 1979.
Jupiter's moon Ganymede is larger than the planet Mercury.
If Jupiter were about 80 times more massive, it could have become a star.
Exploration history
Pioneer 10 1973
First spacecraft to fly past Jupiter.
Galileo 1995-2003
First Jupiter orbiter; dropped a probe into the atmosphere.
Juno 2016+
Currently orbiting, studying Jupiter's interior, gravity, and polar storms.
Europa Clipper 2030 (arrival)
NASA mission en route to study Europa's hidden ocean.
Jupiter vs Earth
| Property | Earth | Jupiter |
|---|---|---|
| Diameter | 12,742 km | 139,820 km |
| Year length | 365 days | 11.9 years |
| Moons | 1 | 95 |
| Day length | 24 hours | 9.9 hours |
| Mass | 1x | 318x Earth |
Scientific Sources & Provenance
All data is verified against official space agency records (NASA, ESA, and IAU).
- NASA Science / Mission Datahttps://science.nasa.gov/jupiter/
- NASA Science / Mission Datahttps://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html
- NASA Science / Mission Datahttps://europa.nasa.gov/