Do "completely dark" dark matter halos exist?

San Diego CA (SPX) Apr 14, 2025
Every galaxy is thought to form at the center of a dark matter halo - a region of gravitationally bound matter that extends far beyond the visible boundaries of a galaxy. Stars are formed when gravity within dark matter halos draws in gas, but astrophysicists don't yet know whether star-free dark matter halos exist. Now Ethan Nadler, a computational astrophysicist at UC San Diego, has calc