Department of Astronomy


Taking Supernova Cosmology into the New Decade


Michael Wood-Vasey

University of Pittsburgh


Type Ia supernovae played an important role in launching the recent explosion of interest in dark energy. The original discovery of dark energy was with fewer than 100 supernovae. Current efforts to characterize the equation-of-state of dark energy have brought us to 1,000 supernovae. As we enter a new decade that will finish with at least 100,000 supernovae, it is time to take stock of where the field is and what challenges confront us.

The current hand-wringing in Type Ia supernova cosmology centers around unknown systematics that could confuse evolution in the brightness of a Type Ia supernova with a change in luminosity distance in the Universe. Specifically, we need to improve our understanding of the current correlations of brightness with of host galaxy dust, mass, and star formation. With the significant increase in supernova samples with Pan-STARRS1, SkyMapper, DES, and eventually LSST we can tackle these systematics by exploring the rich samples that will be gathered across environments and redshift. I will present the latest supernova results from the Pan-STARRS1 survey and share my thoughts on the best ways to make optimal use of the unprecedented numbers of supernovae that we will have observed by the end of the decade and invite discussion on the most likely physical underpinnings of dark energy.