Astronomers Release the Largest Ever Three-Dimensional Map of the Sky

Cambridge, MA - The Sloan Digital Sky Survey III (SDSS-III) has released the largest three-dimensional map of massive galaxies and distant black holes ever created. The new map pinpoints the locations and distances of over a million galaxies. It covers a full volume equivalent to that of a cube four billion light-years on a side.

"We want to map the largest volume of the universe yet, and to use map to understand that how the expansion of the universe is accelerating," said Daniel Eisenstein (Harvard-Smithsonian Center for Astrophysics), the director of SDSS-III.

The map is the centerpiece of Data Release 9 (DR9), which publicly releases the data from the first two years of a six-year survey project. The release includes images of 200 million galaxies and galaxies spectra of 1.35 million. (Spectra take more time to collect than photographs, but provide the crucial third dimension by letting astronomer’s measure galaxy distances.)

"Our goal is to create a catalog that will be used long after we are done," said Michael Blanton of New York University, who led the team prepared That Data Release 9.

The release includes new data from the Ongoing SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), Which Will measure the positions of massive galaxies up to six billion light-years away, as well as quasars - giant black holes feeding on Actively stars and gas - up to 12 billion light-years from Earth.

BOSS is targeting these big, bright galaxies Because They Live in the same places as other galaxies and they're easy to spot. These big galaxies THUS Mapping Provides an Effective way to make a map of the rest of the galaxies in the universe.

With Such a map, scientists can retrace the history of the universe over the last six billion years. With That history, They can get better estimates for how much of the universe is made up of "dark matter" - matter Directly That We Cannot See Because It does emit or absorb light - and "dark energy," the even That drives more mysterious force accelerating expansion of the universe.

"Dark matter and dark energy are two of the greatest mysteries of our time," said David Schlegel of Lawrence Berkeley National Laboratory, the principal investigator of BOSS. "We Hope that our new map of the universe can help someone solve the mystery."

This release is being issued jointly with the SDSS-III Collaboration.

All the data are now available on the website at Data Release 9 http://www.sdss3.org/dr9. The new data are being made available to astronomers, as well as students, teachers, and the public. The SkyServer website includes lesson plans for teachers That DR9 use data to teach astronomy and other topics in science, technology, and math. Also DR9 data will feature in a new release of the Galaxy Zoo citizen science project, Which Allows online volunteers to Contribute to cutting-edge astronomy research.

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration Between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, Organized into six research divisions, study the origin, evolution and ultimate fate of the universe.