How Big Is Jupiter?

How big is Jupiter compared to Earth?

Jupiter is enormous. According to NASA, Jupiter's diameter is about 86,881 miles (139,820 km), roughly 11 times Earth's diameter. About 11 Earths could line up across Jupiter's face. By volume, Jupiter is about 1,321 times the size of Earth, meaning you could fit roughly 1,300 Earths inside it. Jupiter's mass is about 318 times Earth's, and its surface gravity at the cloud tops is about 2.5 times Earth's.

How does Jupiter compare to other planets?

Jupiter is the largest, by far. It's more massive than all the other planets in our solar system combined, more than twice as massive as Saturn (the next-largest planet), and over 5,000 times more massive than tiny Mercury. Jupiter's volume alone is about 60 percent of all the planetary volume in the solar system. The planet is so big that if you were to weigh everything in the solar system except the Sun, Jupiter alone would tip the scale by a wide margin.

Could Jupiter become a star?

Not with its current mass. Stars form when hydrogen at their core is compressed enough to ignite nuclear fusion, which requires immense gravity and pressure. Jupiter would need to be about 80 times its current mass to become even a small red dwarf star. Despite being mostly hydrogen and helium (the same materials stars are made of), Jupiter simply isn't massive enough to compress its core to the temperatures and densities needed for fusion. It's often called a failed star, but it's more of a never-could-have-been.

Why is Jupiter so big?

Jupiter formed in the right place at the right time. Early in the solar system's history, Jupiter's region contained large amounts of hydrogen, helium, ice, and dust beyond the frost line, where volatile compounds could remain solid. Jupiter accumulated a large rocky core first, then its gravity attracted enormous amounts of gas from the surrounding disk. The accumulation was rapid, possibly over a few hundred thousand years, before the Sun cleared the leftover material.