NASA改變下降衛星預測 現在可能擊中北美！

NASA Changes Prediction On Falling Satellite Now May Hit North America!
NASA改變下降衛星預測 現在可能擊中北美！
2011-09-23


美國宇航局的UARS衛星墜落在太平洋上
Nasa's UARS satellite plunges over Pacific
By Jonathan Amos
Science correspondent, BBC News
Translation By Autumnson Blog

The BBC's Andy Moore says where debris has landed is "a bit of a mystery"
BBC的Andy Moore說，碎片的降落地點仍是“一個謎。”
The spacecraft was expected to fall to Earth by about 0500 GMT - officials say it is not possible yet to give a precise time.
飛船預計將下降到地球約0500格林尼治標準時間 - 官員說他尚未能給出一個精確時間。
The Upper Atmosphere Research Satellite (UARS) is the largest American space agency satellite to return uncontrolled into the atmosphere in about 30 years.

Officials said the risk to public safety was remote.

A statement on the Nasa UARS website read: "The Joint Space Operations Center at Vandenberg Air Force Base in California said the satellite penetrated the atmosphere over the Pacific Ocean. The precise re-entry time and location are not yet known with certainty."

There have been some unconfirmed reports on Twitter that suggested debris might have fallen in western Canada.

Most of the decommissioned spacecraft should simply have burnt up, but modelling work indicated perhaps 500kg could have survived to the surface.

Any pieces of debris should have been scattered over a 800km path; but with more than 70% of the Earth's surface covered by water, many experts said the pieces were most likely to end up in the ocean.

Stephen Cole, a Nasa spokesman in Washington DC, told BBC News: "You have to remember that they're very, very small pieces, even though the original satellite was large - as large as a bus. Most of that burns up in the atmosphere and just a few dozen pieces survive. They're highly damaged, and if they're in the ocean - they're gone."

UARS was deployed in 1991 from the space shuttle Discovery on a mission to study the Earth's upper atmosphere.

It contributed important new understanding on subjects such as the chemistry of the protective ozone layer and the cooling effect volcanoes can exert on the global climate.

For more please read:
http://www.bbc.co.uk/news/science-environment-15034073

六噸重美國衛星殘骸即將墜落地球
更新時間 2011年9月24日, 格林尼治標準時間02:42

美國宇航局預計，重約六噸的一塊美國衛星殘骸將於星期六（9月24日）格林尼治標準時間早晨三點至七點之間墜落地球。

宇航局科學家早些時候為預測衛星殘骸的墜落地點而頗費思量。此前的預測說，大約有26塊較大的碎片會墜落在地表800公里範圍內。

宇航局表示，在衛星殘骸墜落過程中，它們將經過加拿大、非洲、澳大利亞和太平洋、大西洋和印度洋的大片區域。

美國宇航局說，衛星殘骸對公眾安全構成威脅的風險很小。

這顆廢棄的科研衛星將是30年來墜落地球的最大人類飛行物。但衛星殘骸的大部分將在重入大氣層時燒燬。
http://www.bbc.co.uk/zhongwen/trad/rolling_news/2011/09/110924_rolling_nasa_satellite.shtml

Falling Nasa Satelite Video Footage
NASA墜落衛星的錄像
2011-09-23


Dead satellite's fall now delayed
死衛星的下墜現在延遲
2011-09-23


今天小心那衛星

NASA下墜衛星最後的墳墓 可能保持一個謎