UPDATE Interview with NASA specialist in space debris as satellite races towards Earth

Описание: (23 Sep 2011) SHOTLIST
FILE: Cape Canaveral, Florida, US - 12 September 1991
1. Various of UARS Satellite being launched aboard a space shuttle ++MUTE++
2. Wide of space shuttle taking off ++MUTE++
3. Wide of space shuttle in sky ++MUTE++
Cape Canaveral, Florida, US - 23 September 2011
4. SOUNDBITE (English) Mark Matney, NASA orbital debris scientist:
"Our current projection is that the spacecraft will fall some time Friday night or early Saturday morning, US time."
NASA ANIMATION
5. Animation of UARS Satellite in space ++MUTE++
Cape Canaveral, Florida - 23 September 2011
6. SOUNDBITE (English) Mark Matney, NASA orbital debris scientist:
"In the last 24 hours something has changed about the spacecraft, either its orientation and/or its shape, in such a way that the drag rate has dropped slightly, the aerodynamic forces are less. As a result it has delayed the time of re-entry."
FILE: Space - 15 September 1991
7. Various of UARS being deployed from shuttle''s open payload bay
Cape Canaveral, Florida, US - 23 September 2011
8. SOUNDBITE (English) Mark Matney, NASA orbital debris scientist:
"As the spacecraft gets lower in altitude the aerodynamic forces begin to increase. And several possible things can happen: one is the orientation of the spacecraft can change, it can weathervane, or you might think of like a shuttlecock in badminton. It may orient itself to present a lower profile to the aerodynamic forces. Alternately (he means alternatively) the forces can actually change the appendages on the spacecraft and change its shape. These can cause again the aerodynamic forces to be reduced and delay its time of re-entry."
FILE: Space - date unknown
9. STILL showing UARS in space
STORYLINE
A 6-ton NASA satellite on a collision course with Earth clung to space on Friday, apparently flipping position in its ever-lower orbit and stalling its death plunge.
The old research spacecraft, the Upper Atmosphere Research Satellite, or UARS, was expected to crash into the Earth''s atmosphere some time on Friday night or early Saturday morning.
Most of the satellite should burn up during re-entry.
On Friday night, NASA said it expected the satellite to come crashing down between 11:45 p.m. on Friday and 12:45 a.m. EDT on Saturday. It was going to be passing over the Atlantic, Pacific and Indian oceans at that time, as well as Canada and Africa.
Until Friday, increased solar activity was causing the atmosphere to expand and the 35-foot (11-metre) satellite to free fall more quickly.
But late on Friday morning, NASA said the sun was no longer the major factor in the rate of descent and that the satellite''s position, shape, or both, had changed by the time it slipped down to a 100-mile (160-kilometre) orbit.
"In the last 24 hours, something has happened to the spacecraft," said NASA orbital debris scientist Mark Matney.
It was still unknown exactly where and when the satellite would re-enter the atmosphere.
"It is still too early to predict the time and location of re-entry with any certainty," NASA said in a statement.
The Aerospace Corporation, which tracks space debris, estimates the strike will happen some time between about 6 p.m. and 4 a.m. EDT (2200 and 0800 GMT).
Those late-night, early morning passes show the satellite flying over parts of the United States.
Any surviving wreckage is expected to be limited to a 500-mile (800-kilometre) swath.
UARS will be the biggest NASA spacecraft to crash back to Earth, uncontrolled, since the post-Apollo 75-ton Skylab space station and the more than 10-ton Pegasus 2 satellite, both in 1979.

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