An Astronomical Time Machine: Light Echoes from Historic Supernovae

Johns Hopkins University, Baltimore MD

Investigators

Abstract

The investigator has discovered a way to study the 3-dimensional (3D) properties of a Supernova (SN), by observing SN light that only now reaches Earth, after bouncing off dust filaments. These light echoes provide a unique opportunity in astronomy: direct observation of the cause (the explosion) as well as the effect (the expanded remnant) of the same astronomical event. Because the light echoes come from many directions around the supernovae, a 3D model of the event can be constructed. The investigators plan public outreach talks, video summaries of their research and citizen science opportunities for the public. The light echoes are novel events and are naturally great introductions to the history of astronomy, light travel time, SN explosion physics, and the advantage of spectroscopy compared to historical brightness measurements. They are developing interactive learning materials available for introductory undergraduates. They have an exciting Citizen Science plan, which enables the public to learn the scientific process by identifying new light echoes in their observations. The 3D model is valuable because modern theoretical work suggests that asymmetry may be a critical ingredient in the SN explosion mechanism. The investigators will expand their program to regularly observe 6 historical SN events. They will observe with the NSF?s Blanco telescope, a large telescope, with a 4-meter aperture size. The 3-degree square field of view, combined with the fast 20 second readout of DECam, this the ideal telescope for this search. Since their targets are generally older than already detected supernovae, they expect the targets to be slightly fainter. They will produce many 5 minute duration images a night. They will use computers programmed for machine learning to identify echoes. They will compare their machine learning results with Citizen Science analysis of the same images. 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.