In the 1990's two teams of astronomers independently foundthat the expansion of the universe was in fact speeding up, contrary to popularopinion at the time. The leader of one team was AAAS member Saul Perlmutter, who it wasannounced will receive half of the 2011 Nobel Prize in Physics for hisdiscovery. The other half of the prize will be split between the leaders ofthe other team, Brian Schmidt and Adam Riess.
Perlmutter is the head of the Supernova Cosmology Project atthe Lawrence Berkley National Laboratory at the University of California,Berkeley. By observing distant stars and supernovas Perlmutter concluded thatthe universe was expanding at an increasingly rapid pace.
Popular opinion atthe time held that the universe's expansion must be slowing down as gravitypulled the galaxies together. However the independent discovery by two teamsrocked the scientific world. Researchers now believe there must be anotherforce acting against gravity in deep space, that fuels the increasing pace ofthe universe's expansion. This other force is being called dark matter, asubstance researchers are still trying to measure and study.
Perlmutter told the Associated Press that he was surprisedby the win, and at first thought the telephone call informing him he'd won wasa hoax. "Nobody really expects a Nobel Prize call," Perlmutter told AP by telephone shortly after Tuesday's announcement inStockholm. Perlmutter will receive his half of the prize in Sweden in December.