Jupiter
The King of Planets
Jupiter is the largest planet in our solar system — over 1,300 Earths could fit inside it. Its Great Red Spot is a storm larger than Earth that has raged for over 350 years. Jupiter acts as a cosmic vacuum cleaner, its immense gravity deflecting asteroids and comets that might otherwise hit Earth. It has 95 known moons, including the four Galilean moons discovered in 1610.
Mass
1.90 × 10²⁷
kg
Diameter
139,820
km
Gravity
24.79
m/s²
Temperature
-110
°C cloud top
Day Length
9.9
hours
Year Length
11.86
Earth years
Distance from Sun
778.5
M km
Atmosphere
90% H₂, 10% He — no solid surface
Moons(4)
Io
The most volcanically active body in the solar system, with over 400 active volcanoes. Tidal forces from Jupiter constantly knead its interior.
Europa
Has a subsurface ocean beneath its icy crust that contains more water than all of Earth's oceans combined. Top candidate for extraterrestrial life.
Ganymede
The largest moon in the solar system — even bigger than Mercury. The only moon with its own magnetic field.
Callisto
The most heavily cratered object in the solar system. May also harbor a subsurface ocean. A potential base for future Jupiter exploration.