WASHINGTON -- Peering into the dim glow from the explosive birth of the universe, astronomers for the first time have seen the seeds of matter that over the eons grew into gigantic galaxies of stars.
The astronomers said the patterns of seeds represent the oldest and largest structures in the universe.
The findings could revolutionize astronomy, the scientists said, by helping to solve several major problems, including how galaxies formed and why they clump together in huge "superclusters."
"English doesn't have enough superlatives . . . to convey the story" of the new results, said George Smoot of the University of California at Berkeley, leader of the team that reported the discovery. "We have observed . . . 15 billion-year-old fossils that we think were created at the birth of the universe."
Mr. Smoot said at a scientific meeting here yesterday the discovery indicated the universe must contain large amounts of exotic matter unlike the protons and neutrons of ordinary atoms.
Furthermore, the new work will enhance progress in cosmology, the study of the entire universe, by ruling out a variety of theories proposed in recent years.
"This is a major step forward for cosmology," said Princeton University astrophysicist David Spergel, who was not involved in the study. "It's exciting, because now we really know what's the right direction to go. The whole field of cosmology will be different after this meeting."
The new evidence came from NASA's Cosmic Background Explorer satellite, or COBE, launched into orbit in November 1989. COBE's instruments probe the cold bath of microwave radiation believed to be the remnant of the cosmic explosion known as the big bang.
COBE's first findings, reported in 1990, provided some of the strongest evidence to date that the universe was born in such a cosmic explosion, roughly 15 billion years ago.
The new reports add further support to the big-bang scenario.
"The big bang is alive and well -- very alive and well," said astrophysicist Edward Wright of the University of California, Los Angeles, and a member of the COBE team.
Initial COBE data did not show any temperature variations in the background radiation. Except for illusory differences caused by the Earth's motion through space, the radiation temperature is just under 3 degrees above absolute zero no matter what direction in the sky it comes from.
Small temperature differences should have been caused, however, by lumps of matter present when the big bang's fireball subsided enough for atoms to form, about 300,000 years after the universe was born.
Since the discovery of the background radiation in 1964, astronomers had searched unsuccessfully for evidence of those primordial lumps of matter. By attracting more matter through the force of gravity, those seeds would have grown into the galaxies that populate the universe.
In recent years, astronomers have found larger and larger clusters of galaxies apparently speeding through space at hundreds of miles per second. These features were hard to explain without any information about the seeds from which they grew.
The seeds were hard to detect because the temperature differences they created were very small -- only 30-millionths of a degree apart from point to point in the sky, the COBE scientists reported.
Measuring such variations is as difficult as trying to determine whether Mount Everest has grown or shrunk by an inch.
Theorists say the COBE results are consistent with several proposals on how galaxies and galaxy clusters formed. In particular, the COBE findings support the popular "inflation" model for the birth of the universe and the subsequent formation of large-scale galactic structures.