Jupiter’s wild youth may have reshaped the entire Solar System

Using advanced computer simulations, planetary scientists André Izidoro and Baibhav Srivastava found that Jupiter's rapid early expansion disturbed the disk of gas and dust surrounding the young sun. The planet's strong gravitational pull generated ripples throughout the disk, creating what they describe as "cosmic traffic jams" that kept small particles from falling into the sun. Instead, these particles accumulated in dense bands, allowing them to merge into planetesimals, the solid precursors of planets.

Second-Generation Planetesimals and the Origin of Chondrites

A key finding from the study is that the planetesimals forming within these bands were not the solar system's original building blocks. They were part of a later generation and formed at a time that matches the birth of many chondrites, a class of stony meteorites that contain both chemical and chronological clues from the solar system's earliest era.

"Chondrites are like time capsules from the dawn of the solar system," said Izidoro, assistant professor of Earth, environmental and planetary sciences at Rice. "They have fallen to Earth over billions of years, where scientists collect and study them to unlock clues about our cosmic origins. The mystery has always been: Why did some of these meteorites form so late, 2 to 3 million years after the first solids? Our results show that Jupiter itself created the conditions for their delayed birth."

Chondrites are especially important because they preserve some of the most untouched material available for scientific study. Meteorites from the first generation of planet-building objects melted and transformed, losing much of their original structure. In contrast, chondrites retain primitive solar system dust as well as small molten droplets called chondrules. Their unexpectedly late formation has challenged researchers for decades.

"Our model ties together two things that didn't seem to fit before -- the isotopic fingerprints in meteorites, which come in two flavors, and the dynamics of planet formation," Srivastava explained. "Jupiter grew early, opened a gap in the gas disk, and that process protected the separation between inner and outer solar system material, preserving their distinct isotopic signatures. It also created new regions where planetesimals could form much later."

How Jupiter Helped Shape the Inner Solar System

The research also sheds light on another puzzle: why Earth, Venus and Mars orbit near 1 astronomical unit from the sun instead of spiraling inward, a common outcome in many planetary systems observed around other stars. By blocking the inward flow of gas, Jupiter prevented young planets from migrating toward the sun. As a result, these worlds remained in the terrestrial zone, where Earth and its neighboring planets eventually formed.

"Jupiter didn't just become the biggest planet -- it set the architecture for the whole inner solar system," Izidoro said. "Without it, we might not have Earth as we know it."

The team's conclusions align with ring-and-gap patterns now seen in the disks of young star systems observed through the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in northern Chile. These structures show how forming giant planets can reshape their surroundings.

"Looking at those young disks, we see the beginning of giant planets forming and reshaping their birth environment," Izidoro said. "Our own solar system was no different. Jupiter's early growth left a signature we can still read today, locked inside meteorites that fall to Earth."

This research was supported in part by the National Science Foundation (NSF), the NSF-funded Big-Data Private-Cloud Research Cyberinfrastructure and Rice's Center for Research Computing.