What Can Meteorites Tell Us About The Formation Of Jupiter? Comment

Gas giants like Jupiter are a fundamental component of planetary systems, but how they formed has been uncertain. Here we discuss how paleomagnetic records in meteorites of the solar nebula may tell us about Jupiter's final growth stage. We suggest that under certain testable assumptions, the meteorite data indicate that proto-Jupiter grew from a mass of similar to 50 Earth masses (M-circle plus) at >3.46 million years (Ma) after solar system formation to its final mass of 318 M-circle plus over just <0.5 Ma. This rapid acceleration is consistent with a key prediction of the core accretion model for giant planet formation.Plain Language Summary Giant planets like Jupiter are composed largely of hydrogen and helium with small amounts of rocky and icy material. They formed from the gaseous reservoirs present during the formation stage of solar systems known as protoplanetary disks. Considerable theoretical progress has been made on understanding Jupiter's formation, yet there have been few observational constraints on its growth rate. In this Commentary, we synthesize meteorite compositional and magnetism data to glean insights into Jupiter's growth, arguing that Jupiter formed slowly over several million years before growing at least 30 times faster to reach its final mass. This long timescale and late, rapid acceleration match models showing that Jupiter formed first with the assembly of a rock-ice core followed by rapid accretion of gas. We can further test this idea with future astronomical observations of young star systems, magnetic measurements of meteorites, and theoretical studies that track the evolution of meteorite parent bodies.