After days of seeming uncertainty, official satellite-watchers announced Tuesday that a dead NASA satellite broke up over the South Pacific, about as far away from large land masses as you can get.
NASA said the U.S. Air Force calculated that the 20-year-old Upper Atmosphere Research Satellite entered Earth's atmosphere generally above American Samoa at midnight ET Friday. Pieces of it started hitting the water another 300 miles (480 kilometers) to the northeast, southwest of Christmas Island, NASA said.
"It's a relatively uninhabited portion of the world, very remote," NASA orbital debris scientist Mark Matney said. "This is certainly a good spot in terms of risk."
Scientists who track space junk couldn't be happier with the result. "That's the way it should be. I think that's perfect," said Bill Ailor, director of the Center for Orbital and Reentry Debris Studies at the Aerospace Corp. "It's just as good as it gets."
The satellite was deployed into orbit in 1991 from the space shuttle Discovery to study Earth's upper atmosphere and its interaction with solar radiation and particles. Findings from the $740 million UARS mission helped confirm the link between Earth's ozone hole and emissions of industrial chemicals known as chlorofluorocarbons. In 2005, the mission ended and the satellite was placed into a gradually decaying disposal orbit.
No credible sightings reported
NASA and the Air Force alerted the general public almost three weeks ago that the satellite's end was near.
"Six years after the end of its productive scientific life, UARS broke into pieces during re-entry, and most of it burned up in the atmosphere," NASA wrote in a final status update.
Experts believe about two dozen metal pieces, weighing about 1,200 pounds (500 kilograms) in all, survived re-entry and fell over a 500-mile (800-kilometer) span.
"NASA is not aware of any possible debris sightings from this geographic area," the space agency said.
On Saturday, scientists said it was possible some pieces could have reached northwestern Canada, but NASA said Tuesday that the newly announced calculations show it landed earlier than they thought, nowhere near North America.
NASA wouldn't say exactly how it knew that the climate research satellite came in earlier, referring questions to the U.S. Air Force's Joint Space Operations Center. Air Force spokeswoman Julie Ziegenhorn said better computer model reconstruction after the satellite fell helped pinpoint where the satellite returned to Earth.
Anatomy of a hoax
Immediately after the satellite's fall, one series of reports claimed that glowing bits of satellite debris were sighted over Okotoks in the Canadian province of Alberta. The reports began to go viral via Twitter, but the updates on the disposition of the debris soon took a sci-fi turn.
"The ground is covered with splinters of a tree it must have struck on its way down," one update read.
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Over the weekend, a Calgary filmmaker named Sebastian Salazar acknowledged that he was behind the "Oko-hoax," with the updates based on passages lifted from H.G. Wells' "War of the Worlds."
"I just started copying word for word what was on there, including the characters," Salazar told the Calgary Sun. He signaled the hoax by using the name "imnotgonnalie2u" for the Twitter account, with a winking face as the account's icon.
"The news guys weren't picking it up; they were, 'all right, we're going to wait for confirmation,' and good for them," Salazar said.
The Royal Canadian Mounted Police said they had no credible reports of satellite debris sightings. RCMP Sgt. Patrick Webb said Salazar would face no charges in connection with the stunt, and even played along with the joke. "We've only apprehended three little green men," he told the Calgary Herald. "We'll get those little buggers yet."
This report includes information from msnbc.com and The Associated Press.
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