— Hubble telescope captures striking image of a dying galaxy.
"For this supernova, we were able to make ultra-rapid observations with Hubble, giving unprecedented coverage of the region right next to the star that exploded.".
Helpfully, Hubble also has an archive of observations of this star dating to the 1990s.Astronomers probed the image series and added TESS observations of the system every 30 minutes in the days before the explosion, as well as during the explosion itself and for a few more weeks (before, we assume, the standard schedule of TESS shifted the telescope to gaze at another spot in the sky.).
Scientists then calculated the mass of the exploding star using three different methods: comparing observations with theoretical models, using information from a 1997 archival image of Hubble (this was to rule out higher-mass stars in the model), and measuring the amount of oxygen in the supernova, which is a proxy for mass."This could be a warning system," Foley said of the explosion behavior Hubble and other observatories noted.