Jupiter’s Past Revealed: Once Even Bigger and Stronger
Jupiter’s status as the largest planet in the Solar System is well-known, with a mass that surpasses all other planets combined. However, recent calculations by astronomers Konstantin Batygin and Fred Adams suggest that Jupiter was once even more massive than it is today, with a volume up to 2.5 times larger.
According to their study of Jupiter’s moons, just 3.8 million years after the formation of solid materials in the Solar System, Jupiter had a volume 2 to 2.5 times its current size, along with a much stronger magnetic field.
This finding supports the theory of bottom-up planet formation for gas giants like Jupiter, where gradual accumulation of dust and rocks leads to the creation of a differentiated core.
Batygin explains, “Our ultimate goal is to understand where we come from, and pinning down the early phases of planet formation is essential to solving the puzzle. This brings us closer to understanding how not only Jupiter but the entire Solar System took shape.”
Gas giants like Jupiter are believed to start forming similarly to rocky planets, but once they reach a certain mass, they begin to accumulate a substantial gas envelope due to their strong gravity. This process likely occurred in the outer Solar System due to the lack of material closer to the Sun.
The study of Jupiter’s formation and evolution is crucial in understanding the development of the Solar System. By analyzing the orbits of Jupiter’s moons, the researchers were able to reconstruct the planet’s early history.
The results indicated that Jupiter experienced rapid growth early in the Solar System’s history, reaching at least twice its current volume in just 3.8 million years. Its magnetic field was also significantly stronger, aiding in the accretion of material from the surrounding disk.
As the material around Jupiter dissipated, the planet contracted under its own gravity, reducing its volume and increasing its spin speed. While Jupiter continues to shrink slowly, it was never massive enough to become a star.
The research provides valuable insights into Jupiter’s past and its role in shaping the Solar System, paving the way for a better understanding of planetary evolution.
Batygin concludes, “What we’ve established here is a valuable benchmark, a point from which we can more confidently reconstruct the evolution of our Solar System.”
The study has been published in Nature Astronomy.
