New Study Reveals Jupiter Once Measured Twice Its Current Size

A recent study suggests that Jupiter was much larger and possessed a considerably stronger magnetic field in its early years compared to what we observe today. This research looks back in time to visualize what the planet was like shortly after its formation.

New calculations indicate that just 3.8 million years after the formation of the solar system’s first solid bodies, Jupiter was approximately twice its current size and had a magnetic field at least 50 times stronger than it is today. These findings were presented in a paper published on May 20 in the journal Nature Astronomy, as reported by Space.com.

“Our ultimate aim is to understand our origins, and clarifying the early stages of planetary formation is crucial to solving the puzzle,” stated Konstantin Batygin, a professor of planetary science at Caltech and the study’s lead researcher. “This brings us closer to unraveling how Jupiter and the entire solar system were formed.”

Batygin and his team sought to minimize the assumptions of contemporary planetary formation models, such as how quickly nascent planets accumulated primordial gas. Instead, they focused on Amalthea and Thebe, two lesser-known moons of Jupiter.

Scientists believe that the slightly tilted orbits of these small moons, which orbit closely around Jupiter, have remained relatively unchanged since the early solar system. The recent study claims that by examining these small orbital tilts, researchers could reverse-engineer Jupiter’s initial size and magnetic intensity.

The team estimates that early Jupiter had a capacity to hold more than 2,000 Earths and a radius nearly twice its current measurement. Today, Jupiter can fit about 1,321 Earths within its volume.

This study emphasizes that Jupiter’s formation and early growth were critical in shaping the overall structure of the solar system, although it does not delve into how such a colossal Jupiter might have influenced the early solar system’s development.