Supernovae, TDEs, and Scintillation: How ASKAP and Rubin Are Mapping the Variable Universe
Multi-messenger astrophysicsShow Notes
In this episode, we dive into how astronomers are combining the power of the Australian Square Kilometre Array Pathfinder (ASKAP) and the Vera C. Rubin Observatory to capture the dynamic, ever-changing sky in real time.
Historically, optical and gravitational-wave observatories issued rapid alerts, but radio astronomy lacked automated, large-scale, real-time alert infrastructure. Now, a long-term monitoring program (project AS331) targets Rubin’s Deep Drilling Fields (DDFs), taking 3-hour radio snapshots approximately every 10 days to achieve a sensitivity of \\(\sim 60\ \mu\text{Jy}\\). This complementary survey automatically processes and streams radio data to the global astronomical community in near-real-time without human intervention.
Episode Highlights & Key Discoveries: Bridging Optical and Radio Astronomy: How contemporaneous, non-coordinated radio surveys solve the bottleneck of follow-up observations for millions of optical alerts. Tidal Disruption Events (TDEs): Updated high-cadence light curves for AT2018hyz, revealing late-time radio flaring and scintillation effects that constrain the outflow size. Supernova Interaction: Modelling circumstellar material interactions around the Type IIb supernova SN2024abfo. New Cosmic Discoveries: The detection of ASKAP J095711.5+051205 (a candidate optical-less TDE in a poststarburst galaxy) and ASKAP J005026.4-422958 (an ongoing Extreme Scattering Event caused by plasma lensing).
### Article Reference Title: ASKAP Monitoring of the Rubin Deep Drilling Fields Authors: Dougal Dobie, James Freeburn, Iris de Ruiter, Katie Auchettl, James Coulson, Brent Miszalski, Anais Möller, and Nikhil Sarin Identifier: arXiv:2610.13011v1
Acknowledements: Podcast prepared with Google/Gemini Notebook. Illustration credits: CSIRO
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