Nasa satellite breaks up, plunges back to earth
Florida, September 24, 2011
A six-tonne NASA science satellite pierced the atmosphere over the Pacific Ocean and fell back to Earth, the US space agency said on Saturday, but it was not yet known where the remains landed.
Nasa said its decommissioned Upper Atmosphere Research Satellite, which took an unpredictable course as it tumbled through the upper atmosphere, fell to Earth sometime between 11:23 p.m. EDT on Friday and 1:09 a.m. EDT on Saturday.
"The precise re-entry time and location are not yet known with certainty," Nasa said of the 20-year-old satellite.
There were reports on Twitter of debris falling over Okotoks, a town south of Calgary in western Canada, most likely satellite remains.
Stretching 35 feet long and 15 feet in diameter, UARS was among the largest spacecraft to plummet uncontrollably through the atmosphere, although it is a slim cousin to Nasa's 75-tonnes Skylab station, which crashed to Earth in 1979.
Russia's last space station, the 135-tonnes Mir, crashed into the Pacific Ocean in 2001, but it was a guided descent.
Nasa now plans for the controlled re-entry of large spacecraft, but it did not when UARS was designed.
The 5,897 kg satellite was dispatched into orbit by a space shuttle crew in 1991 to study ozone and other chemicals in Earth's atmosphere. It completed its mission in 2005 and had been slowly losing altitude ever since, pulled by the planet's gravity.
Most of the spacecraft burned up during the fiery plunge through the atmosphere, but about 26 individual pieces, weighing a total of about 500 kg could have survived the incineration.
The debris field spans about 500 miles, but exactly where it is located depends on when UARS descended.
With most of the planet covered in water and vast uninhabited deserts and other land directly beneath the satellite's flight path, the chance that someone would be hit by falling debris was 1-in-3,200, Nasa said.
"The risk to public safety is very remote," it said.
The satellite flew over most of the planet, traveling between 57 degrees north and 57 degrees south of the equator.
UARS was one of about 20,000 pieces of space debris in orbit around Earth. Something the size of UARS falls back into the atmosphere about once a year.-Reuters
More INTERNATIONAL NEWS Stories
- $5bn poll spend to boost India economy
- Libya authorises use of force against Korean tanker
- Ukraine PM says he will go to US to discuss crisis
- Syrian journalist killed covering fighting
- Malaysian jet may have turned back before vanishing
- No sign of missing plane; Malaysia probes false passports
- Two Europeans not on board 'missing' Malaysian jet
- China draws red line on North Korea
- Saudi sentences three to death for 2003 bombing
- First bitcoin machine opens in UK
- US sanctions will boomerang, warns Russia
- China plans $50bn bank to fund projects
- Sony to sell Tokyo 'birthplace'
- Obama orders sanctions over Russian moves
- Crimea parliament votes to join Russia
- Arab League to be revamped
- 'Upskirting' is legal: Massachusetts court
- Singapore probes 'unnatural' death of bitcoin trader
- Onus on world powers for Syria war crimes: UN
- US, Russia set for talks on Ukraine crisis
- Brent oil drops below $109
- Services outshine manufacturing, pushing up jobs
- Bitcoin bank shut down after hacker attack
- India to kick off world's biggest poll on April 7
- China signals focus on reforms
- Hundreds ready for bitcoin exchange class action
- Space taxi, Jupiter mission in Obama budget
- Putin: Use of force last resort in Ukraine
- Powers to boost Lebanese military, economy
- Egypt bans Hamas activities in Egypt