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Friday, January 14, 2022
7:00 PM - 9:00 PM
Online Event

Stargazing Lecture

How to Rip Apart a Star
Samantha Wu, PhD Candidate, Department of Astronomy, Caltech,

Because this is an online event, the in-person stargazing that normally follows events in this series will not be possible.

Join the YouTube Livestream here:

7:00–7:30 p.m. - Virtual Lecture
7:30–9:00 p.m. - Virtual Panel Q&A and Discussion

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.

About the Series

Stargazing Lectures are free lectures at a public level followed by a Q&A panel and guided stargazing with telescopes (weather permitting). All events are held at the Cahill Center for Astronomy and Astrophysics at Caltech. No reservations are needed. Lectures are 30 minutes; stargazing and panel Q&A last 90 minutes. Stay only as long as you want.

Stargazing is only possible with clear skies, but the lecture and panel Q&A takes place regardless of weather.

For directions, weather updates, and more information, please visit:

For more information, please contact Cameron Hummels by email at