Weighing Galaxies

We live in a galaxy of about a hundred billion stars, the Milky Way. As the sky over Mount Tam darkens, and the stars in the disk of our galactic home come into view, see how we are mapping out where the Dark Matter is, both in our local group of galaxies and further out in the depths of space. Galaxies are much heavier than they look – what could that mean for our understanding of how stars form, and what Dark Matter is?

Speaker: Dr. Phil Marshall, Kavli Institute