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Entries in UARS (5)

Tuesday
Sep272011

NASA UARS Satellite Crash Site Confirmed in Pacific

NASA(VANDENBERG AIR FORCE BASE, Calif.) -- NASA now says the final resting place of its UARS satellite is a remote part of the South Pacific, halfway between Australia and Hawaii. The satellite fell to Earth just after midnight, EDT on Saturday morning, after days in which scientists speculated about where it would come down.

In an update, based on information from the Air Force Joint Space Operations Center at Vandenberg Air Force Base in California, NASA said, “The satellite entered the atmosphere over the Pacific Ocean at 14.1 degrees south latitude and 189.8 degrees east longitude. This location is over a broad, remote ocean area in the Southern Hemisphere, far from any major land mass. The debris field is located between 300 miles and 800 miles downrange, or generally northeast of the re-entry point. NASA is not aware of any possible debris sightings from this geographic area.”

UARS’s debris – if anything in fact reached Earth’s surface – is far from land, but also far from the area off the Pacific Northwest where NASA said on Saturday it thought the satellite could have come down. For all the precision involved in launching a spacecraft and tracking it in orbit, tracking its demise is still inexact. NASA said the upper layers of the atmosphere are highly variable, which is why it was so hard to say just where UARS was slowed enough that it could no longer maintain orbital speeds.

NASA had said that the odds were in 1 in 3,200 that anyone on Earth would get hit.

Copyright 2011 ABC News Radio

Friday
Sep232011

NASA Now Predicts Satellite Re-Entry Friday Night or Saturday Morning

Artist's rendering of the Upper Atmosphere Research Satellite (NASA)(WASHINGTON) -- Re-entry of NASA's abandoned UARS satellite into earth's atmosphere is expected late Friday or early Saturday, the space agency said in a new update. While NASA maintains that it will not be over North America at that time, they also insist it's too early to predict the time and location of re-entry with real certainty.

"The satellite's orientation or configuration apparently has changed, and that is now slowing its descent," said NASA in an update. "There is a low probability any debris that survives re-entry will land in the United States, but the possibility cannot be discounted because of this changing rate of descent."

At last report, UARS was just over 100 miles in altitude. The atmosphere there, thin as it is, is thick enough to slow the satellite until it finally cannot stay in orbit.

The Aerospace Corporation, a private firm in California that is tracking UARS, independently predicted the satellite would come down around 11:16 p.m. EST, in an oval area that includes countries in northern Africa from Libya to Chad. But it said the time could change by several hours.

NASA said some 26 chunks of the old satellite -- which is roughly the size of a bus -- are likely to survive the descent, and fall at hundreds of miles per hour over an area of some 500 square miles. The agency has said it knows of no case in which people have been hurt by space junk.

"We believe that the risk is sufficiently low that no one needs to change their behaviors," NASA's Mark Matney said.

This is the largest NASA satellite to fall back to Earth uncontrolled since Skylab in 1979. Skylab was much larger -- about the size of a house -- and debris fell in the Australian Outback and the Pacific.

But according to Nicholas Johnson, NASA's chief orbital debris scientist, any one person's chances of getting hit by debris are tiny -- something like 1 in 21 trillion. The chances that of the 7 billion people on Earth, one of them, somewhere, could be hit are more like 1 in 3,200.

Copyright 2011 ABC News Radio

Friday
Sep232011

Falling Satellite Forecast to Re-Enter Friday Afternoon off Chilean Coast

Conceptual image of the Upper Atmosphere Research Satellite. NASA(HOUSTON) -- If you live in North America and are wondering where NASA's aging Upper Atmosphere Research Satellite (UARS) will crash on Earth, the space agency says you can rest easy.

"Re-entry is possible sometime during the afternoon or early evening of Sept. 23, Eastern Daylight Time," NASA said in an update Thursday night.  "The satellite will not be passing over North America during that time period."

The Aerospace Corporation, a private firm that is tracking UARS, offered a more specific prediction, saying the satellite would likely come down off the coast of Chile at 6:06 p.m. EST.  But William Ailor, who heads the company's center for orbital and re-entry debris studies, said the time and location would almost undoubtedly change as Friday afternoon approaches.

NASA repeated that the risk to people or property is "extremely small."

As of Thursday evening, UARS had an altitude of about 110 miles, skimming the uppermost reaches of the atmosphere at more than 17,000 mph.  At some point, a little like a stone skipping over a pond, it will encounter enough resistance that it will no longer be able to keep moving at orbital speeds.

UARS is the largest NASA satellite to fall back to Earth uncontrolled since Skylab in 1979.  It is 35 feet long and weighs about six tons, but most of it will burn up on re-entry.  The little that doesn't is what worries NASA.

Nicholas Johnson, NASA's chief orbital debris scientist, said their analysis shows that 26 parts of UARS are dense enough to make it to the Earth's surface.

"These 26 components, which we anticipate will survive all the way down, will be going at a moderate velocity of tens to hundreds of miles an hour," he said.  "All these 26 have been identified as potentially causing damage if they hit a structure or a person, but the odds of that are very, very, low."

Johnson said any one person's chances of getting hit by debris are tiny -- something like 1 in 21 trillion.  The chances that one of the seven billion people on Earth could be hit are more like 1 in 3,200.

Copyright 2011 ABC News Radio

Tuesday
Sep202011

Space Satellite UARS Expected to Hit Earth Friday

Conceptual image of the Upper Atmosphere Research Satellite. NASA(HOUSTON) -- On Friday, the first day of fall in the northern hemisphere, a 20-year-old dead satellite will re-enter the atmosphere, a little sooner than NASA anticipated.

Originally, the space agency predicted the nearly 6-ton Upper Atmosphere Research Satellite, or UARS, could hit the planet as early as Sept. 24.

While NASA can basically track the arrival of UARS, figuring out where it will fall is another matter entirely.  NASA officials told ABC News that they won't know where the satellite will hit until two hours before it enters the Earth's atmosphere.  And the target range for where the satellite might fall is broad: 57 degrees north of the equator to 57 degrees south of the equator.

UARS will break into pieces as it crashes toward Earth but not all of it will burn up.  Scientists have identified 26 separate components that will likely survive with the debris, spreading out over 400 to 500 miles.  Engineers say 1,200 pounds of metal chunks could make it down to the surface.

NASA said the chances of anyone getting hit by the satellite are 1 in 3,200.

Copyright 2011 ABC News Radio

Friday
Sep162011

Space Satellite UARS Adrift and Heading for Earth

Conceptual image of the Upper Atmosphere Research Satellite. NASA(HOUSTON) -- A nearly 6-ton satellite is heading toward Earth and could crash into the planet as early as Sept. 24, NASA officials said.

The UARS -- short for Upper Atmosphere Research Satellite -- has been in orbit since the space shuttle Discovery launched it in 1991, but it's gradually coming closer to the ground as it encounters friction from the upper reaches of the atmosphere.

NASA officials told ABC News that they won't know where the satellite will hit until two hours before it enters the Earth's atmosphere, moving at 5 mph.

The chances of anyone getting hit by the UARS satellite are 1 in 3,200, NASA said.

The "productive science life" of the satellite ended in 2005 when it ran out of fuel, according to NASA's website.  That fuel could have been used by the satellite to ditch itself in the Pacific.

The satellite will break into pieces as it crashes toward Earth but not all of it will burn up.  Scientists have identified 26 separate components that will likely survive with the debris, spreading out over 400 to 500 miles.  Engineers say 1,200 pounds of metal chunks could make it down to the surface.

"Things have been re-entering ever since the dawn of the Space Age; to date nobody has been injured by anything that's re-entered," Gene Stansbery of NASA's orbital debris office told ABC News last week.

The target range for where the satellite might fall is broad: 57 degrees north of the equator to 57 degrees south of the equator.

Copyright 2011 ABC News Radio







ABC News Radio