A joint Fermilab/SLAC publication
Illustration of "spectroscopy" (red and blue)


Spectroscopy is a technique that astronomers use to measure and analyze the hundreds of colors contained in the light emitted by stars, galaxies and other celestial objects.

Illustration of: Dark Universe Feature (purple and yellow)

Illuminating the dark universe

The pursuit of dark matter and dark energy is one of the most exciting—and most challenging—areas of science. Now researchers think they’re beginning to close in.

Image of Essay: A Galaxy with a View: Cerro Tololo

A galaxy with a view

A physicist, a software developer and a writer step outside one night to take in nature’s beauty at a mountaintop observatory in Chile.

Photo of LCLS SXR

Ironing out an astrophysics problem

Using an X-ray laser, scientists unravel the longstanding conundrum of why extreme plasmas in space look different than expected.

Illustration purple space, sea-foam green galaxies, planet in center, yellow telescope coming out of orange circle eye inside

Complex simulations: a driving force for LSST

The Large Synoptic Survey Telescope, the world’s largest sky survey, will rain a monsoon of data onto the astrophysics community. Simulations prepare scientists for the approaching storm.

Photo of Roger Romani

Stellar black widows entrap companion stars

Of the hundreds of objects in the universe emitting gamma rays, two look to be "black widows," ancient stars extending their lives by sucking in material from companion stars. Stanford physicist Roger Romani is hot on the trail of these extreme stars.

Logbook of Cosmic rays

Cosmic rays

Enrico Fermi's notebook of December 1948 contains four pages that represent the genesis of his theory of cosmic rays, particles that can hit the Earth's atmosphere at high speeds.

Illustration of quasars' view of early universe - BOSS SDSS-III

BOSS collaboration measures expansion of the universe 11 billion years ago

The BOSS collaboration has looked so far back in time that they observed the period before dark energy began to dominate the largest scales of the universe.

Photo of Fermi Symposium 2012

Social scientists: Far-flung physicists meet face-to-face

A tidal wave of gamma-ray scientists swept into Monterey, California, for the Fourth International Fermi Symposium, and despite the idyllic photo of a lovely local beach that graced the event poster, they didn’t come for the sun and surf. They came for science—and some face time.

Photo of Stars per 100 billion cubic light years

Fermi telescope gazes through fog to count the stars

A recent measurement of how many gamma rays make it through a cosmic “fog” of starlight reveals just how many stars there are in the universe.