WASHINGTON - The discovery by John Mather and George Smoot of "cosmic ripples," which won them the Nobel Prize in physics on Tuesday, was lauded in 1992 by cosmologist Stephen Hawking as "the greatest discovery of the century, if not of all time."

While most physicists do not go that far, they are universal in their praise of the experiment, in which the pair and their team designed a satellite and used it to find proof of the Big Bang theory of the universe's origins.

They found faint variations in microwave radiation that dated back to just 300,000 years after the fiery birth of the universe.

These ripples in the microwave radiation, they said, were the primordial framework on which the galaxies, stars and other stuff of the universe took shape. It explained why the universe is lumpy and not a smooth sheet of matter and energy.

"The discovery changed everything," said Lawrence Krauss, a theoretical physicist at Case Western University in Ohio.

"It produced a revolution in what we know about the universe -- we know it is expanding, we know it is flat ... and we can measure that to an incredible accuracy," Krauss said in a telephone interview.

"Cosmology now is a precision science."

Until then, theoretical physicists had cobbled together small pieces of evidence that the universe and everything in it had appeared suddenly about 15 billion years ago from an infinitesimally small point in a vacuum of nothingness.

When the 40-member research team announced some of their findings to a meeting of physicists in 1992, an "audible gasp was heard from the audience," according to the American Institute of Physics.

Stephen Hawking, the Cambridge University physicist who explained theories about how the universe was formed in his popular book "A Brief History of Time," was one of most excited. "It is the discovery of the century, if not of all time," Hawking said in a statement at the time.

FILLING IN THE BLANKS

"I don't think he was completely out of control," Krauss said. People had known what to look for. "The picture, however, had been blank up to then," he said.

"Then it was clear -- it wasn't a vague idea. It was clear the lumps were there."

These fluctuations were faint variations in temperature, and scientists have since followed up on those measurements to try to understand, for instance, dark matter -- mass that no one has been able to see or measure but which must exist because of the amount of gravity measured in the universe.

Some teams have come up with new theories of dark energy -- a mysterious force that may be accelerating the expansion of the universe.

While the implications may far outlast humanity -- the end of the universe may be coming in a few more billion years -- Smoot has been clear on the need for the work.

"It is extremely important for human beings to know their origins and their place in the world," Smoot said in a statement.

Krauss said the prize supports his own arguments -- made toNASA and the U.S. Congress -- that funding should go to similar experiments.

President Bush has urged NASA to concentrate on getting people to the moon and Mars.

"New experiments on the cosmic microwave background, new experiments to probe dark energy, to look for habitable planets -- all these have been delayed and/or canceled because we are sending people back to the moon," Krauss said.