Princeton University

In Search Of: Failed Supernovae

Christopher Kochanek
Ohio State University
May 12, 2015

Failed supernovae, where core collapse leads to the formation of a black hole without an external supernova, have always been one of the possible outcomes when a massive star dies.  The observed properties of the dying, progenitor stars, mismatches between the star formation and supernova rates, the black hole mass

Heavy Element Synthesis in the Universe

Enrico Ramirez-Ruiz
University of California, Santa Cruz
April 28, 2015

The source of about half of the heaviest elements in the Universe has been a mystery for a long time. Although the general picture of element formation is well understood, many questions about the nuclear physics processes and particularly the astrophysical details remain to be answered. Here I focus on advances in our understanding of the origin of the heaviest and rarest elements in the Universe.

Enigmatic Enceladus

Peter Goldreich
California Institute of Technology & Institute for Advanced Study
April 7, 2015

Saturn’s satellite Enceladus displays a bewildering array of thermal activity. I will describe our attempts to understand these phenomena in terms of tidal heating associated with the 2:1 mean motion resonance between Enceladus and Dione. Then I will argue that Enceladus and the other midsize satellites of Saturn are young.