Multi-messenger and Multi-wavelength follow-up with ASAS-SN

With the discovery of the first optical counterpart for both a high-energy neutrino source and a gravitational-wave source, 2017 kicked off the age of multi-messenger astronomy. Now, 5 years later the optical follow-up landscape for multi-messenger astronomy is rapidly evolving. In this talk, I will first discuss the status and future of the All-Sky Automated Survey for Supernovae (ASAS-SN), an all-sky optical survey with more than a decade of data from 20 telescopes at 4 sites around the world. I will review: 1) ASAS-SN’s LIGO O3 follow-up efforts, 2) ASAS-SN’s IceCube follow-up coverage and detected counterpart candidates including the discovery of the flaring blazar coincident with high-energy neutrino IceCube-170922A, and 3) our ASASN-SN Optical/Fermi 𝛾-ray blazar flare correlation study. I will finish by presenting our future LIGO and IceCube follow-up strategy, shaped by the lessons learned from these earlier follow-up efforts, and now including triggering immediate spectroscopic follow-up from the Spectral Classification of Astronomical Transients (SCAT) survey on the UH 2.2m telescope.