Jupiter
Gas Giant
Distance from Sun
778.5 M km
Orbital Period
11.86 years
About Jupiter
Jupiter is the largest planet in our solar system, with a mass more than twice that of all the other planets combined. This colossal gas giant is composed primarily of hydrogen and helium, with no solid surface beneath its swirling, colorful cloud bands. Its immense gravity has shaped the architecture of the entire solar system, acting as both a cosmic shield by deflecting asteroids and comets, and as a gravitational sculptor of nearby orbits.
The planet's atmosphere is a dynamic showcase of extreme weather. Wind speeds can exceed 600 km/h, and the iconic Great Red Spot is a storm larger than Earth that has been raging for at least 350 years. Jupiter's banded appearance results from ammonia crystal clouds organized into alternating zones and belts driven by powerful jet streams flowing in opposite directions.
Jupiter also possesses a faint ring system, an enormous magnetosphere extending millions of kilometers, and a diverse system of moons. The four largest, known as the Galilean moons (Io, Europa, Ganymede, and Callisto), are worlds unto themselves, with Europa considered one of the most promising places to search for extraterrestrial life due to its subsurface ocean.
Key Facts
- Jupiter's Great Red Spot is a persistent anticyclonic storm larger than Earth, observed since at least 1831 and possibly since 1665.
- The planet has the shortest day of any planet in the solar system, completing one rotation in just under 10 hours.
- Jupiter's magnetic field is approximately 20,000 times stronger than Earth's, creating intense radiation belts.
- Ganymede, Jupiter's largest moon, is bigger than the planet Mercury and is the only moon with its own magnetic field.
- Europa's subsurface ocean likely contains twice as much water as all of Earth's oceans combined.
- Jupiter emits more energy than it receives from the Sun due to slow gravitational contraction and residual heat from its formation.
- If Jupiter had been about 80 times more massive, it would have become a star through hydrogen fusion.
Exploration History
Pioneer 10 & 11 (1973-1974)
First spacecraft to fly through the asteroid belt and past Jupiter, returning the first close-up images.
Voyager 1 & 2 (1979)
Discovered Jupiter's faint rings, volcanic activity on Io, and detailed the complex Jovian atmosphere.
Galileo (1995-2003)
First spacecraft to orbit Jupiter. Deployed an atmospheric probe and provided evidence for subsurface oceans on Europa.
Juno (2016-present)
Currently studying Jupiter's composition, gravity field, magnetic field, and polar magnetosphere from a polar orbit.
Europa Clipper (2024)
Launched in October 2024 to conduct detailed reconnaissance of Europa and investigate its habitability.
You could fit more than 1,300 Earths inside Jupiter. Despite its enormous size, Jupiter has the shortest day in the solar system, spinning so fast that the planet visibly bulges at the equator, making its diameter 7% wider side-to-side than pole-to-pole.