Abstract: In this talk I will review progress in planet formation, with a focus on the basic question of how rapidly it occurs. Solar System evidence traditionally favors a slow track, with the final assembly of terrestrial planets taking 100 Myr, and Uranus and Neptune interpreted as core that failed to grow to gas giants. Recent observations of protoplanetary disk substructure, interpreted as planet-disk interactions, suggest a dramatically different history, with planets forming rapidly even at large orbital distances. Fast planet formation, if confirmed, would support a modern theoretical scenario that starts with planetesimal formation via gravitational collapse and continues with a dominant role for pebble accretion in growth. I will discuss our simulation work on prompt planetesimal formation, and how that piece of the puzzle can be independently tested via observations in the Kuiper Belt.
Host: Eric Feigelson
Astro Colloquium and 'coffee & cookies' Department gathering (3:30-4:00pm)