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Universe Might be Bigger and Older than Expected

Thursday, August 10, 2006

A project aiming to create an easier way to measure cosmic distances has instead turned up surprising evidence that our large and ancient universe might be even bigger and older than previously thought.

If accurate, the finding would be difficult to mesh with current thinking about how the universe evolved, one scientist said.

A research team led by Alceste Bonanos at the Carnegie Institution of Washington has found that the Triangulum Galaxy, also known as M33, is about 15 percent farther away from our own Milky Way than previously calculated.

The finding, which will be detailed in an upcoming issue of Astrophysical Journal, suggests that the Hubble constant, a number that measures the expansion rate and age of the universe, is actually 15 percent smaller than other studies have found.

Currently, most astronomers agree that the value of the Hubble constant is about 71 kilometers per second per megaparsec (a megaparsec is 3.2 million light-years). If this value were smaller by 15 percent, then the universe would be older and bigger by this amount as well.

Scientists now estimate the universe to be about 13.7 billion years old (a figure that has seemed firm since 2003, based on measurements of radiation leftover from the Big Bang) and about 156 billion light-years wide.

The new finding implies that the universe is instead about 15.8 billion years old and about 180 billion light-years wide., Ken Than More:Universe Might be Bigger and Older than Expected