Title: How cores grow by pebble accretion
Authors: Mark Brouwers, Allona Vazan, Chris Ormel
First Author’s Institution: Anton Pannekoek Institute, University of Amsterdam
Status: Submitted to A&A [open access]
Do you know how gas giant planets form in a protoplanetary disk? It all starts with a bunch of planetesimals (km-sized and above) that collide together one-by-one until they grow into an object that is the largest in the neighborhood. As the biggest object in its vicinity, this protoplanet core will naturally continue to collect and accrete more planetesimals until it consumes everything nearby. Eventually, the core will grow large enough to build up a significant atmosphere from the gas that makes up the disk. Once its atmosphere becomes more massive than the core itself, it will become unstable and devour a ton more gas — thereby growing to roughly Jupiter’s size.If anyone tells you they know how gas giants form and provides an explanation of the process (like I did above), it might be a good idea to ask them: How long does that process take? Protoplanetary disks – a gas giant’s source of gas – only live about 3 million years on average. Yet, the original model (a classic ...