Distant Black Holes Map Universe's Dark Energy History
Zosia Rostomian, Lawrence Berkeley National Laboratory; Nic Ross, BOSS Lyman-alpha team, Berkeley Lab; and Springel et al, Virgo Consortium and Max Planck Institute for Astrophysics
November 14, 2012 12:59 PM
Light from distant quasars (red dots at left) is partially absorbed as it passes through clouds of hydrogen gas. Astronomers working on the BOSS survey used this effect to study the history of dark energy in the universe's ancient past.