August 22, 2025 8-10 PM

Event Type: Lecture and Stargazing
Title: Cosmic Fireworks: How Astronomers Explore the Changing Sky
Lecturer: Sam Rose
Position: PhD Candidate
Institution: Caltech
Abstract:
The Universe evolves over the course of billions of years—a timescale almost incomprehensible to humans. But there are some things in the night sky that change much faster. Spectacular explosions of massive stars dying, pulsing stars, and comets and asteroids drifting through our Solar System are all examples of changes in the sky that happen over the course of weeks, months, or years. These events which cause new sources of light to appear and disappear in the sky are called “astronomical transients.” In this talk, we will explore the history of astronomical transients: including observations of an exploding star by Chinese astronomers in 1054 CE, the search for comets over the centuries, and the first large-scale surveys of the sky using the Mt. Wilson and Palomar observatories. We will also cover the next-generation efforts to detect these events using Caltech's very own Zwicky Transient Facility (ZTF) and the brand new Vera Rubin Observatory, which will reveal millions of new asteroids and supernovae across the sky in the coming years.