Stockholm, Oct 4 (IANS) Three scientists Tuesday won the 2011 Nobel Prize in Physics for their studies of exploding stars that revealed the universe was expanding quickly.


Saul Perlmutter and Adam G. Riess, from the US, shared the honour with Brian P. Schmidt from Australia.

"They have studied several dozen exploding stars, called supernovae, and discovered that the universe is expanding at an ever-accelerating rate," Staffan Normark, permanent secretary of the Royal Swedish Academy of Sciences, said in a statement.

Perlmutter was honoured for his contributions to the Supernova Cosmology Project and Riess "for the discovery of the accelerating expansion of the universe through observations of distant supernovae".

Schmidt is associated with the High-z Supernova Search Team in Australia, Xinhua reported.

The acceleration is thought to be driven by dark energy, but what that dark energy is remains a mystery.

"Therefore the findings of the 2011 Nobel laureates in physics have helped to unveil a universe that to a large extent is unknown to science. And everything is possible again," the statement said.

This was the second of this year's crop of Nobel Prizes, which are handed out annually for achievements in science, literature, economics and peace.

The winners of chemistry will be announced Wednesday, literature Thursday, peace Friday and economics next Monday.

On Monday, American Bruce Beutler and French scientist Jules Hoffmann shared the Nobel Prize in Medicine with Canadian Ralph Steinman.

The annual Nobel Prizes are usually announced in October and are handed out Dec 10, the anniversary of the 1896 death of Alfred Nobel, a Swedish industrialist and inventor of dynamite.

All but one of the prizes were established in the will of 19th century dynamite millionaire Nobel. The economics award was established by Sweden's central bank in 1968.

Nobel dedicated his vast fortune to creating prizes for those who have conferred the greatest benefit on mankind.

The prizes have been awarded since 1901. Each prize consists of a medal, a personal diploma and a cash award of 10 million Swedish kronor (about $1.46 million).