spacetoday.net: Astronomers win Physics Nobel for expanding universe discovery

Posted: Wed, Oct 5, 2011, 7:47 AM ET (1147 GMT)
Three astronomers will share the 2011 Nobel Prize in Physics for their discovery that the expansion of the universe is accelerating. The Royal Swedish Academy of Sciences awarded the prize Tuesday to Saul Perlmutter of the University of California Berkeley, Brian Schmidt of the Australian National University, and Adam Reiss of Johns Hopkins University and the Space Telescope Science Institute. The three astronomers led teams that found in the late 1990s that the universe was not only expanding, but that expansion is accelerating. The astronomers observed distant supernovae that served as "standard candles" that astronomers used to determine their distances, and hence the expansion rate of the universe. That expansion has since been linked to the presence of dark energy, which makes up over 70 percent of the universe but whose nature remains a mystery.