Astronomers were able to establish the original size of Jupiter just after the formation of the solar system. It was twice as large and had a much stronger magnetic field than today.
Studying the early evolution of Jupiter plays a huge role in understanding how our solar system formed its structure. The gas giant is often described as its “architect”. Jupiter’s powerful gravity played a crucial role in shaping the orbital trajectories of the other planets and influenced the gas-dust disk from which they formed.
In their new study, which was published in the journal Nature Astronomy, scientists from the California Institute of Technology and the University of Michigan took a detailed look at Jupiter’s primordial state. Their calculations showed that about 3.8 million years after the first solids formed in the solar system (the key moment when the disk of matter around the Sun began to dissipate), the planet was much larger and had a very powerful magnetic field.
The researchers came to this conclusion by studying Amalthea and Thebe. These are two inner moons of Jupiter, which are so close to the gas giant that from their surface it looks like a huge disk with a diameter dozens of times larger than the Moon.
Because the orbits of Amalthea and Thebe are slightly tilted, scientists analyzed these small orbital discrepancies to calculate Jupiter’s original size. Calculations have shown that immediately after its formation, the gas giant had a radius twice as large as today. Its volume was 2,000 times that of Earth. The researchers also determined that Jupiter’s magnetic field at that time was about 50 times stronger than now.
The new results add important details to existing theories of planet formation, which suggest that Jupiter and other giants formed by core accretion, a process in which a rocky and icy core rapidly accumulates gas. According to the researchers, although the first moments of the gas giant’s existence are still shrouded in a veil of uncertainty, the current study has established a valuable point of reference on which they can more confidently reconstruct the evolution of our solar system.
Earlier we reported on how the James Webb Telescope photographed the auroras on Jupiter.
According to Phys.org
