Schematic of Supernova 2014C
This schematic shows the various ejecta and winds (red and purple) given off by the exploding star (left, yellow). The common-envelope disk (blue) surrounds both stars, the one exploding as a supernova and its binary partner (not shown). The boundary layer around the common-envelope disk is the source of the hydrogen the team detected. (credit: B. Thomas et al./UT Austin)