天宮一號：中國空間實驗室已經落在南太平洋

(本文翻譯自：Tiangong-1: Defunct China space lab comes down over South Pacific)

中國和美國的報道稱，已經廢棄的天宮一號空間實驗室主要是在南太平洋上空重新進入地球大氣層時解體的。

Chinas defunct Tiangong-1 space lab mostly broke up on re-entering the Earths atmosphere above the South Pacific, Chinese and US reports say.

中國載人航天工程辦公室說，它在周一00:15的時候重新進入大氣層。

It re-entered the atmosphere around 00:15 GMT on Monday, Chinas Manned Space Engineering Office said.

天宮一號於2011年發射，進行對接和軌道實驗。

Tiangong-1 was launched in 2011 to carry out docking and orbit experiments.

這是中國在2022年建立載人空間站的努力的一部分，但在2016年3月停止了工作。

It was part of Chinas efforts to build a manned space station by 2022, but stopped working in March 2016.

我們知道它落在哪裡了嗎？

What do we know about where it came down?

「南太平洋上空」這個相當模糊的詞是來自太空官員的。

The rather vague "above the South Pacific" is the line from space officials.

聯合部隊空間組件司令部的美國專家表示，他們已經使用軌道分析技術來確認天宮一號的重返大氣層。

US specialists at the Joint Force Space Component Command said they had used orbit analysis technology to confirm Tiangong-1s re-entry.

來自哈佛-史密森天體物理中心的天文學家喬納森·麥克道爾在推特上說，它似乎是在塔希提島的西北部出現的。

Astronomer Jonathan McDowell, from the Harvard-Smithsonian Center for Astrophysics, tweeted that it appeared to have come down north-west of Tahiti.

專家們一直在努力預測實驗室到底能夠重新進入的位置 - 而中國的太空機構錯誤地表示在這一時刻到來前不久，它將離開巴西聖保羅。

Experts had struggled to predict exactly where the lab would make its re-entry - and Chinas space agency wrongly suggested it would be off Sao Paulo, Brazil, shortly before the moment came.

歐洲航天局(European Space Agency)提前表示，天宮一號可能會在覆蓋地球表面大部分地區的水域上空解體。

The European Space Agency said in advance that Tiangong-1 would probably break up over water, which covers much of the Earths surface.

報告強調說，碎片擊中人的概率是「是被閃電擊中的概率的一千萬分之一」。

It stressed that the chances of anyone being hit by debris from the module were "10 million times smaller than the yearly chance of being hit by lightning".

目前還不清楚到底有多少碎片完好無損地到達了地球表面。

Its not clear how much of the debris reached the Earths surface intact.

太空實驗室為什麼會這樣墜落?

Why did the space lab fall like this?

理想的情況下，10米(32英尺)長的天宮模塊將會以有計劃的方式脫離軌道。

Ideally, the 10m (32ft)-long Tiangong module would have been taken out of orbit in a planned manner.

傳統上，推進器被發射到大型車輛上，把它們推進到南大洋的一個偏遠地區。在失去了命令鏈接後，這個選項似乎沒有可用。

Traditionally, thrusters are fired on large vehicles to drive them towards a remote zone over the Southern Ocean. This option appears not to have been available after the loss of command links.

在歐洲航天局(European space Agency)的領導下，13個航天機構利用雷達和光學設備觀測跟蹤了天宮一號在全球的運行軌跡。

Thirteen spaceagencies, under the leadership of the European Space Agency, used radar and optical observations to follow Tiangongs path around the globe.

天宮的意思是「天上的宮殿」

Tiangong means Heavenly Palace

天宮模塊於2011年開始練習交會對接

The module was launched in 2011 to practise rendezvous and docking

2012年和2013年，兩名宇航員參觀了「神舟膠囊」。

Two astronaut crews visited in Shenzhou capsules - in 2012 and 2013

他們是中國首位女宇航員劉洋和王亞萍

They included Chinas first female astronauts Liu Yang and Wang Yaping

中國計劃在未來10年建立一個更具有永久性的空間站

China plans a more permanent space station in the next decade

為了達成這一目的，中國已經開發出一款重型火箭名為長征5

It has developed a heavy-lift rocket, Long March 5, for the purpose

天宮一號是史上最大的人造太空設備嗎？

Is this the biggest space hardware to fall out

of the sky?

天宮的確是巨大的、返回時不受控制的人造太空設備，但它遠不是最大的，歷史上:

Tiangong was certainly on the large size for uncontrolled re-entry objects, but it was far from being the biggest, historically:

1979年，美國太空總署的太空實驗室達到了將近80噸。當它返回地球時，部分碎片襲擊了西澳大利亞，但沒有人受傷。

The US space agencys Skylab was almost 80 tonnes in mass when it came back partially uncontrolled in 1979. Parts struck Western Australia but no-one on the ground was injured.

Nasa的哥倫比亞太空梭重返大氣層時也是不受控制的。2003年，當它從軌道上返回時，它的質量超過了100噸。這一次和以往一樣，地面上沒有人被擊中，碎片散落在美國德克薩斯州和路易斯安那州。

Nasas Columbia shuttlewould also have to be classed as an uncontrolled re-entry. Its mass was more than 100 tonnes when it made its tragic return from orbit in 2003. Again, no-one on the ground was hit as debris scattered through the US states of Texas and Louisiana

天體物理學家喬納森·麥克道爾(Jonathan McDowell)認為，天宮是第50個返回地球時無法控制的巨大人造太空設備。

Astrophysicist Jonathan McDowell believes Tiangong is only the 50th most massive object to come back uncontrolled.

中國已經啟動了第二個天宮2號實驗室，該實驗室將繼續運作。就在去年，「天舟一號」(Tianzhou-1)的一艘補給貨輪也造訪了它。

China has launched a second lab, Tiangong-2, which continues to be operational. It was visited by a re-fuelling freighter, Tianzhou-1, just last year.

亞洲國家表示，中國未來的永久性空間站預計將包括一個大型核心模塊和兩個較小的輔助模塊，並將在未來十年內投入使用。

Chinas future permanent space station is expected to comprise a large core module and two smaller ancillary modules, and will be in service early in the next decade, the

最近推出了一種新型長征5號火箭，用於完成將核心模塊送入軌道所需的繁重工作。

A new rocket, the Long March 5, was recently introduced to perform the heavy lifting that will be required to get the core module in orbit.

翻譯： @浪流海北@JellyJelly@unclethree39

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