March 22, 2001 -- Scientists reckon the odds of being hit by a piece of falling space junk are around one in a trillion. Tulsa resident Lottie Williams was that unlucky one.

Williams, 48, was exercising in a Tulsa park one morning four years ago when she was hit on the shoulder by a six-inch piece of blackened metallic material.

A used Delta II rocket had crashed into the Earth's atmosphere half an hour earlier, and scientists at NASA believe that Williams was hit by a part of it — making her the only person in the world known to have been hit by man-made space debris.

Her story is no comfort to Pacific Islanders nervous about the Mir space station, which is due to re-enter over the Pacific Ocean early Friday morning. Most of the station will burn up as it hits the atmosphere, but scientists say as much as 20 tons of debris will fall to Earth, in chunks weighing up to 1,500 pounds.

The leaders of 16 Pacific island nations have sought assurances that parts of Mir will not land on them. The Russian space agency is aiming to have the debris fall in unpopulated parts of the ocean.

Great Ball of Fire

Williams saw the rocket entering the atmosphere a half-hour before she was hit. She was out walking in the park with friends around 3:30 a.m., part of a regular routine she uses to get exercise around her work schedule, when they saw a flash in the sky.

"I noticed in the sky there was this big bright light, like a fire," she remembers. "I turned to my friends to say look and when I turned back it was coming towards us. I didn't say anything else. It was coming over the park and as it approached us it got bigger. All the colors that you see that come from fire, all those colors were there. It was like this big huge ball of fire, across this park."

Eventually, she says, the fireball shot off two sparks and disappeared over a building.

She initially thought she had seen a star. "I thought the two sparks was a star giving birth to new stars."

Blackened Fragment

She went back to her walking, but, shortly into her third mile, she felt a tap on her left shoulder. Something hit her and rolled off on to the ground with a metallic sound. She kicked it into the light, then picked it up cautiously (she was wearing gloves) and took it to her truck.

The object was blackened on the edges, and consisted of layers of a light metallic material. The impact of the object, very thin and light — a little bigger than the palm of her hand — startled, but didn't injure her.

Later that day, she started making inquiries, calling the local library, then the National Guard. "He thought I was a kook. I can understand that," says Williams, who said she has a government job but didn't elaborate.

Ultimately, the U.S. Space Command in Colorado Springs, Colo., confirmed that a Delta II rocket body had reentered the atmosphere around 3:30 a.m. over the southern central part of the country. There were sightings reported in Texas, Kansas, Missouri and Arkansas.

The rocket had been launched nine months earlier, in April 1996, carrying a military satellite.

NASA tests showed that Williams' fragment was consistent with the materials of the rocket, and Nicholas Johnson, the agency's chief scientist for orbital debris, believes that she was indeed hit by a piece of the rocket.

"It looks as though one lady who was standing outside, early morning in Tulsa, Okla., was actually struck by the piece on the back," Johnson says.

"It was so light-weight that it really hit her like a feather, or a leaf floating off a tree."

Williams says she was disappointed to learn that her fragment didn't come from a star. "I was thinking I had something celestial. And here I got something man-made."

Her advice for the Pacific islanders? Get outdoors and watch, because the fireball makes no noise. "If you're outdoors at least you can see something coming at you.

"Unless it's at night and it comes from behind."

— ABCNEWS' Ned Potter and Tom Johnson contributed to this report.