Is Jupiter a planet-eater? A new report suggests the planet actually behaves like some villain out of a Marvel movie, by consuming whole planets. In fact, the report goes so far as to say that Jupiter achieved its massive size (300 times bigger than Earth) by consuming other worlds in order to build itself up into the biggest planet in our entire solar system, approximately twice the size of all the other planets in this system, combined.
Our results imply that Jupiter continued to accrete heavy elements in large amounts while its hydrogen-helium envelope was growing, contrary to predictions based on the pebble-isolation mass in its simplest incarnation (Lambrechts et al. 2014), favouring instead planetesimal-based or more complex hybrid models (Alibert et al. 2018; Guilera et al. 2020). Furthermore, the envelope did not mix completely during the planet’s subsequent evolution, not even when Jupiter was young and hot (Vazan et al. 2018).
Our result clearly shows the need for further exploration of non-adiabatic interior models for the giant planets, and it provides a base example for exoplanets: a non-homogeneous envelope implies that the metallicity observed is a lower limit to the planet bulk metallicity. Therefore, metallicities inferred from remote atmospheric observations in exoplanets might not represent the bulk metallicity of the planet.
