John Bahcall Colloquium

Prof. Hans-Walter Rix 

Director, Max Planck Institute for
Astronomy, Heidelberg

Date: Dec. 12, 2010

Title: Impressively Unimpressive: the Tiniest of Galaxies

Abstract:

Galaxies are objects where normal, baryonic matter has condensed at
the centers of dark matter mass concentrations and has been turned
into stars. There is a well established, and broadly understood, upper
limit for how many stars can make up a single galaxy. Yet, how few
stars a galaxy can have is not at all understood. And we now know
galaxies that have 100 times fewer stars than the smallest ones known
only 5 years ago. The tiniest galaxies are proving a fabulous
laboratory for understanding how galaxies form and at the same time
provide a unique opportunity to constrain the physical properties of
dark matter.