WASHINGTON, (UPI) -- Using a sensitive telescope hung beneath a giant helium
 balloon, an international team of scientists say they have determined the universe is flat and
 expanding forever.

 Their report, which appears in Thursday's journal Nature, is based on the most detailed picture
 yet of the early universe at a time before the birth of the first stars, when it was just hundreds of
 thousands of years old and far more compact. The researchers say with their work, they have
 greatly updated and sharpened the focus of an image of the early universe. A far more blurry
 image of the early universe released nearly a decade ago was described by one researcher as
 peering at the face of God.

 The data taken by the BOOMERANG experiment shed light, researchers say, on the curvature
 of the universe, the nature of matter and energy in intergalactic space and whether the universe
 will expand forever or collapse into a "Big Crunch."

 "These are literally snapshots of what the universe looked like when it was just a few hundred
 thousand years old, fully a thousand times smaller and hotter than it is today" said Andrew
 Lange of the California Institute of Technology during a press conference Wednesday.

 "What BOOMERANG measures is the heat left over from the Big Bang," Lange said, one of
 the principal investigators in the international research team.

 The experiment's Italian co-leader, Paolo de Bernardis of the University of Rome, said the
 BOOMERANG data may solve several problems, including the total amount of matter and
 energy in the universe.

 The BOOMERANG telescope -- sensitive to microwaves -- circumnavigated Antarctica at a
 height of about 24 miles (38 kilometres) for 10 days in December, 1998. The scientific results
 will also appear in Physical Review Letters, as well as in Nature.

 The sensitive telescope studied the cosmic microwave background radiation, which is believed
 to be the glow of the universe when it was only 300,000 years old, before the birth of the first
 star. Part of the static seen on an unused television channel is caused by the cosmic microwave
 background.

 Among the results claimed by the research team:

 --The universe is flat, in the sense that light beams through intergalactic space that were initially
 parallel would remain parallel and would never meet or diverge.

 --The universe went through a dramatic expansion in size -- called "inflation" -- a split-second
 after the Big Bang.

 --The universe is expanding and will never recollapse into a "Big Crunch."

 University of Chicago theorist Michael Turner said his reaction to the study was, "Wow, wow
 and wow." The first wow, he said, is that the universe is flat, the second is that inflation
 occurred and the third is that, "This is just the beginning. BOOMERANG is beginning to test
 what I think we will call the new cosmology."

 The results of the BOOMERANG experiment are likely to relegate some theories of how the
 universe formed to the scrap heap, according to Canadian team member Richard Bond, a
 theoretician whose mathematical models of the early universe have played a central role in the
 research.

 "We can now take the information and compare it to a vast library of theories," said Bond, of
 the Canadian Institute for Advanced Research and the Canadian Institute for Theoretical
 Astrophysics at the University of Toronto.

 Among the discards, he said, will be any theory that doesn't include inflation -- a rapid
 expansion of the early universe that was first proposed as a way to explain the relative
 uniformity of the universe we now see.

 The new data don't mean inflation is proved, said astrophysicist Wayne Hu of the Institute for
 Advanced Studies at Princeton University, but they are good evidence for the idea. "This was a
 test for the inflation theory," he said -- a test the theory passed.

 Inflation theory predicted that much of the microwave variation would be on a small scale. Hu
 said -- about one degree across, as seen from Earth, and that is precisely what the
 BOOMERANG experiment showed.

 Turner, though, said he thinks, "we're across the threshold" on proof of inflation.

 The BOOMERANG data also appears to settle another long-standing problem: whether the
 universe has enough matter so that its expansion will someday stop, to be followed by a long
 collapse into a fiery "Big Crunch."

 A flat universe, Turner said, can only exist if there is not enough matter to cause it to recollapse.

 De Bernardis said, "We compared our data to (theoretical models of various curved universes)
 and found that the best model is a flat one."

 That discovery, combined with the finding last year that the universe is expanding more quickly
 than expected, allows researchers to calculate how much matter and energy there is in the
 universe, he said.

 About 5 percent of the universe is normal matter and energy, he said. Another 30 percent is
 dark matter, which is undetectable except by gravity. And the rest is what he called "dark
 energy," a still-mysterious form of energy that is driving the speed-up of the universe's
 expansion.

 The cosmic microwave background, or CMB, was discovered by accident in 1965. It was the
 first really solid evidence that the Big Bang really did occur.

 Modern theory says that for the first 300,000 years after the Big Bang, the universe was so hot
 that ordinary matter couldn't form and light particles could not travel ; it was an opaque,
 super-hot, dense fluid. Waves in that fluid, driven by gravity, created spots that were hotter than
 others.

 Then, as the fluid cooled, there came a point where matter formed, light could travel, and the
 universe as we know it could start to form. But, much as we can still feel the heat of a fire even
 though it has gone out, the heat of the fluid left a glow that is still with us as the cosmic
 microwave background.

 Variations in that glow, according to Barth Netterfield of the University of Toronto, the leader
 of the Canadian BOOMERANG contingent, are "the oldest picture of the universe you could
 ever take."

 The first microwave experiment to capture the public's attention was the COBE satellite, whose
 striking image of the universe was made to look like a red and blue Easter egg.

 The team behind COBE -- short for COsmic Background Explorer -- reported their data in
 1992, with the principal investigator, George Smoot, saying the images were like looking at the
 face of God.

 The face of God, however, was blurry: COBE's picture of the microwave background could
 only see variations that were larger than seven degrees across, as seen from Earth. By contrast,
 the moon, which is much nearer, looks to be about half a degree across.

 The BOOMERANG telescope can see variations that are one-sixth of a degree across -- a
 dramatic increase in sensitivity, Netterfield said.

 "To be able to measure this with such precision is just unreal," said Bond. "It's an amazing and
 daunting thing."

 BOOMERANG stands for Balloon Observations of Millimetric Extragalactic Radiation and
 Geomagnetics. The research team included members from the United States, Italy, Canada,
 and the United Kingdom.