Catching Supernovae in Advance

Gemini spectra from Olling et al.

The earliest observations of supernovae can distinguish among their formation mechanisms. For a Type Ia supernova, the progenitor white dwarf may be pushed to become a supernova by merger with another white dwarf or by accretion from a companion. Two new results, led by Rob Olling (University of Maryland) and Yi Ciao (California Institute of Technology), find evidence for both of these processes in different examples, based on early observations from NASA’s Kepler and Swift satellites (see NASA release). In both papers, observations from Gemini and other ground-based facilities provided key evidence to enable classification of the supernovae as Type Ia. The two papers appear in Nature (here and here, subscription required).