NSF Award
2407206
A research collaboration between the University of Hawai’i and Ohio State University will continue to operate the All-Sky Automated Survey for Supernovae (ASAS-SN), which is a network of 20 telescopes deployed at four sites around the globe with a scientific goal to provide a survey of the bright transient and variable astronomical sky. ASAS-SN is the first project to image the entire visible sky on a nightly basis to a visible magnitude of g~18, making the data public. The project discovers and observes approximately 300 supernova per year, and is also an important resource for other science such as active galactic nuclei and blazar flares, tidal disruption events, Galactic and Local Group novae, cataclysmic variables, and other transients. ASAS-SN triggers on events from other NSF-supported facilities, such as astrophysical neutrinos from IceCube and gravitational wave events from LIGO to search for the optical counterparts that are crucial to fully exploring them. ASAS-SN will continue to provide a critical training ground for the next generation of time-domain astronomers and the investigators plan future Citizen Science projects to classify detected objects.<br/><br/>Targeted observations of multimessenger alerts can reach g~20 over 100s of square degrees in a few hours. It is a unique all-sky optical counterpart to other facilities searching for neutrinos, gravitational waves, and gamma rays. The depth of ASAS-SN is nearly perfectly matched to many spacecraft (TESS/Swift for imaging, and HST/CXO/JWST for spectra). Because ASAS-SN transients are bright and promptly announced, they frequently become the best-studied sources in any transient class. Many ASAS-SN sources and transients can be studied in detail for long periods of time, whereas fainter transients cannot. ASAS-SN discovers and recovers ~300 SNe per year, with ~3300 total projected by 2027, the majority with spectroscopic classifications. It will be the largest such sample for studies of rates and correlations by type or with host properties. ASAS-SN provides public databases of 600,000 homogeneously classified variable stars as well as continuously updated light curves of more than 100 million g < 18 sources. This enables new science across many sub-fields of astronomy. ASAS-SN also provides the community with a unique tool to obtain an up-to-date optical light curve for any point on the sky.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
