Astronomers all over the world watched closely Wednesday night as a dead satellite entered the atmosphere and fell to the Earth's surface.

NASA said it would confirm the arrival of the Extreme Ultraviolet Explorer on Earth within eight hours after splashdown, estimating that splashdown would be at 9:25 p.m. MST in the northeast section of the Persian Gulf.

Several faculty members at the University of Colorado were paying special attention to the falling satellite.

Professor Robert Culp of the aoerspace engineering sciences department at CU, an expert on "space junk," said there was little reason to worry that the remnants of the satellite might injure someone on the ground.

"The Earth's surface is about three-quarters water, so the chance of it hitting land is small," Culp said. "But if you think about how unpopulated some parts of the world are, the odds of it landing in a populated area are even smaller. The changes that the debris would hit a person are infinitesimal."

He said that when the Mir space station crashed last year, the only parts to hit land were small fragments that landed in an unpopulated area of Australia.

Professor James Green of the astrophysics department at CU helped to test and build the satellite, know as the EUVE, when he was a graduate student at the University of California at Berkeley. Green worked on the groundbreaking optical devices that the EUVE used to collect data.

"The technology used to detect extreme ultraviolet light was in its infancy when we started on the project," Green said. "The detectors we developed are sort of a space version of night-vision goggles that allow us to 'see' those frequencies of light."

Professor Michael Shull, an astrophysicist at CU, worked with data from the EUVE for several years.

"It opened up a brand-new wavelength band that no one had ever studied," Shull said. "I looked at information from lots of objects outside of the solar system that people didn't think we'd be able to see."

He said he hopes NASA will launch another satellite to study extreme ultraviolet waves sometime in the next decade.

The satellite weighed 7,000 pounds, and most of it was expected to fall apart and burn up in the atmosphere. NASA estimated that the largest single chunk of debris from the EUVE would weight about 100 pounds.

The satellite orbited the Earth over the tropics, so there was no chance for people in Colorado to see the falling craft in the sky.

The EUVE was the first satellite designed specifically to collect images of space objects in the extreme ultraviolet part of the spectrum. The craft was expected to last only three years when it was launched in June 1992, but it remained operational until January 2001.

Although NASA had initially hoped the EUVE would observe 24 nearby space objects, the satellite was able to see more than a thousand, including about 40 from outside the solar system.