Michele Bannister (University of Canterbury, NZ): "Interstellar Worlds: New Insights on Planetary Systems"

Title: "Interstellar Worlds: New Insights on Planetary Systems"

Abstract: The discovery of 1I/‘Oumuamua and 2I/Borisov have created great interest in the population of interstellar objects that pass through the Solar System. These small worlds are samples of the building blocks of planet formation that took place at other stars, but which come close enough for the same detailed physical characterisation possible for Solar System small worlds. 1I/ʻOumuamua and 2I/Borisov share some features with local populations — and a delightful array of variation, hinting at remarkable differences in their original homes. Their 10^26 cousins wandering the Galaxy are part of an overarching cycle of planetesimal formation and scattering over billions of years. I will outline how this vast population of interstellar objects across the Galaxy provide a rich scope of possibilities for linking together very different areas of astronomy, from the formation of planets and their Oort clouds to the star-formation history of the Milky Way.