Speaker: Dr. Craig M Pellegrino

Host: Prof. Tamara Bogdanovic

Title: A New Era of Time-Domain Astronomy: Catching the Fastest, Brightest, and Most Interesting Astronomical Events

Abstract:

 Time-domain astronomy–the study of astronomical events that appear, change in brightness, and disappear on timescales of seconds to years–is currently undergoing a revolution. Survey missions such as the Legacy Survey of Space and Time on the Vera Rubin Observatory, which images the night sky repeatedly, are set to detect millions of these objects each night. This deluge of data opens new discovery spaces, allowing us to identify the fastest-evolving, brightest, and rarest events, and to study them in unprecedented detail. In this talk, I will discuss the current state of time-domain astronomy, focusing on two explosive phenomena: supernovae, the explosive deaths of stars, and kilonovae, the optical counterparts to binary neutron star mergers. Both are intricately tied to many areas of physics and astronomy, from enabling cosmological measurements to providing unique views into the origins of heavy elements and exotic states of matter. I will detail what we currently understand about these objects as well as future studies that will lead to greater insights into their underlying physics. Finally, I will discuss the broader time-domain discovery and follow-up ecosystem, including how alerts are generated, disseminated, and rapidly followed across multiple telescopes and wavelengths. I will introduce a new NASA-led initiative, ACROSS, which aims to improve coordination and response to rare or high-impact transient events, such as nearby supernovae or neutron star mergers—phenomena where rapid observations across the electromagnetic spectrum are critical.