Did Jupiter Collide with a Massive Planet?
A planet 10 times larger than the Earth may have collided with Jupiter as planets were first taking shape, a new computer simulation reveals. This impact, happening 4.5 billion years ago, would have stirred the young core of Jupiter, altering the largest planet of the Solar System until our own time.
Unexpected readings from the Juno spacecraft, studying the massive planet since 2016, found the core of the gas giant is both larger, and less dense, than calculations had predicted, altering what we thought of about the inner structure of Jupiter. This observation sparked researchers to investigate the mystery.
“This is puzzling. It suggests that something happened that stirred up the core, and that’s where the giant impact comes into play,” Andrea Isella, astronomer at Rice University, explains.
Jupiter’s Accidental Encounter
Theories of planet formation suggest that Jupiter started as a dense, frozen, rocky world. This body collected vast quantities of gas over time from the primordial disk forming the Solar System. The core, deep beneath the clouds, was thought to have a smooth surface, the result of enormous gravity and pressure.
Juno measured the gravitational field around Jupiter, revealing a different model.
