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Astronomers with the help of the Baryon Oscillation Spectroscopic Survey data have been able to figure out how fast the universe was expanding just 3 billion years after the Big Bang.

The Baryon Oscillation Spectroscopic Survey is the largest component of the third Sloan Digital Sky Survey (SDSS-III). It also pioneered the use of quasars to map density variation in the intergalactic gas at high redshifts, helping determine the structure of the young universe.

"This means if we look back to the universe when it was less than a quarter of its present age, we'd see that a pair of galaxies separated by a million light years would be drifting apart at a velocity of 68 kilometers a second as the universe expands," said Font-Ribera, a postdoctoral fellow in Berkeley Lab's Physics Division, according to astronomy.com. "The uncertainty is plus or minus only a kilometer and a half per second."

BOSS is able to determine the expansion rate at a given time in the universe by measuring the size of baryon acoustic oscillation (BAO), a signature that is imprinted in the way matter is distributed out of sound waves in the early universe. 

"Three years ago BOSS used 14,000 quasars to demonstrate we could make the biggest 3-D maps of the universe," added Berkeley Lab's David Schlegel, principal investigator of BOSS, according to astronomy.com. "Two years ago, with 48,000 quasars, we first detected baryon acoustic oscillations in these maps. Now, with more than 150,000 quasars, we've made extremely precise measures of BAO."

The findings of the study will be presented at the April 2014 meeting of the American Physical Society in Savannah, GA.