PHILADELPHIA, JAN. 15 -- The cosmos may be much lumpier than previously suspected and may have gotten that way earlier, according to data from the Roentgen Satellite (ROSAT) released today.

"This may be the first glimpse of the structure of the universe" as it existed some 10 billion years ago, said ROSAT scientist Guenther Hasinger of the Max Planck Institute in Germany.

The new observations represent "the deepest X-ray exposure ever taken and the most distant and faintest sources ever seen" in X-ray wavelengths, he said.

Since ROSAT, a joint project of the National Aeronautics and Space Administration, Germany and Great Britain, was launched from Cape Canaveral in June 1990, it has produced the highest-resolution X-ray images ever made of many remote objects in space, according to scientists gathered here for a meeting of the American Astronomical Society.

Among its trophies are 15 formerly undetected radiation sources in the Large Magellanic Cloud (a nearby galaxy), previously unseen remnants of a supernova thought to have exploded some 20,000 years ago and an apparent cluster of quasars (bright sources of energy at the center of galaxies) which may have been formed early in the universe and are enormous distances from Earth.

The last of these observations may add to the continuing disarray among cosmologists. Many currently accepted theories of how the universe took shape after the Big Bang -- the expanding fireball that created the cosmos some 15 billion years ago -- cannot account for such large-scale clumping of matter so early in the evolution of the cosmos.

The new ROSAT data are measurements of X-rays, which are emitted by many objects in space, including certain stars, remnants of supernovas (exploding stars) and quasars, intense radiation sources believed to be lit by the energy emitted as stellar gases swirl into black holes at the center of galaxies. But the wavelength and frequency of those rays appear different depending on how far away the source is.

The reason is that the universe has been expanding since the primeval Big Bang, and the farther away an object is from a given location, the faster it is receding. As the space between any two objects is stretched, light waves traveling from one to the other appear to have a longer wavelength, just as the sound of a train seems to get deeper as it moves away from an observer.

This apparent increase in wavelength is called "red shift" because it shifts the light toward the red (longer wavelength) end of the spectrum. Astronomers can identify the red shift and use the result to determine how far an object is from Earth.

ROSAT scientists believe the X-ray sources they detected have a red shift that puts them 8 billion to 12 billion light years away. That is, the radiation arriving from those objects represents the way they were 8 billion to 12 billion years ago, when the universe was one-third its present age.

But according to many cosmological theories, that is much too early for large-scale aggregations of matter, such as the clusters of galaxies scientists observe now, to have formed.

"The mere existence of {large} structure at these high red shifts is very disturbing to many cosmologists," Hasinger said.