Uncovering the mystery of early massive galaxies running on empty

Early massive galaxies—those that formed in the 3 billion years following the Big Bang—should have contained large amounts of cold hydrogen gas, the fuel required to make stars. But scientists observing the early universe ...

Image: Hubble views a faraway galaxy through a cosmic lens

The center of this image from the NASA/ESA Hubble Space Telescope is framed by the tell-tale arcs that result from strong gravitational lensing, a striking astronomical phenomenon which can warp, magnify, or even duplicate ...

WFIRST will add pieces to the dark matter puzzle

The true nature of dark matter is one of the biggest mysteries in the universe. Scientists are trying to determine what exactly dark matter is made of so they can detect it directly, but our current understanding has so many ...

Gravitationally lensed quasars

The path of light is bent by mass, an effect predicted by Einstein's theory of gravity, and when a massive galaxy or cluster lies along our line-of-sight to a more distant galaxy its matter will act as a lens to image the ...