A cosmic census triples the known number of black holes in dwarf galaxies

The new tally takes a step toward revealing how black holes and galaxies grow together

A line of four telescopes on a mountain ridge under a starry sky

Astronomers are running a vast survey of the cosmos using the DESI instrument on the Mayall Telescope (right) at the Kitt Peak National Observatory in Arizona.

Marilyn Sargent/Berkeley Lab

A colossal census of the cosmos has more than tripled the number of active black holes known to reside in miniature galaxies and found the biggest haul of middleweight black holes to date.