Jupiter is shrinking from being twice as big, stunning study shows

Jupiter's radius was once twice as large as it is now, and the planet's magnetic field was 50 times stronger than it is today. (Photo: K. Batygin)

A new study suggests that Jupiter, the largest planet in our solar system, was once even larger.

The cloud of gas and dust that formed the sun and planets dissipated about 4.5 billion years ago. At that time, Jupiter was at least twice its current volume and its magnetic field was about 50 times stronger, according to data presented by the researchers. The results, described by the team in a study published May 20 in the journal Nature Astronomy, may help scientists gain a clearer picture of the early solar system.

“Our primary goal is to figure out where we came from, and understanding the early stages of planet formation is essential to that goal,” study co-author Konstantin Batygin, a planetary scientist at Caltech, said in a statement. “It brings us closer to understanding how not only Jupiter but the entire solar system formed.”