January 14, 2022 7-9PM

Event Type: Lecture and Stargazing
Title: How to Rip Apart a Star
Lecturer: Samantha Wu
Position: PhD Candidate
Institution: Caltech
Abstract:
Stars traveling through space can sometimes be destroyed by encounters with other nearby objects. If a star wanders too closely to a supermassive black hole, such as the one in the center of the Milky Way, it can be ripped apart in a process known as a tidal disruption event (TDE). As one side of the star experiences a stronger gravitational pull from the black hole than the other side, the black hole's extreme gravity rips material off the star that then flows into the black hole itself. However, even stars that are far away from these supermassive black holes are not always safe from catastrophe. Binary stars, stars that orbit around a companion star, can pass too closely to their neighbors. This process results in the outer layers of the star getting stripped away and consumed by the neighbor, oftentimes leading to an explosive visual display! I will discuss how both these scenarios for ripping apart a star occur and how we see them in action.