Debris from a defunct Chinese space station could crash to Earth as early as Friday, scientists monitoring it say.
The Tiangong-1 was part of China’s ambitious space programme, and the prototype for a manned station in 2022. It was put into orbit in 2011 and five years later completed its mission, after which it was expected to fall back to Earth.
Time and place of impact are hard to predict as it is no longer controlled. The latest estimate for re-entry is between 30 March and 2 April. Most of the station is likely to burn up in the atmosphere but some debris could survive to hit the surface of the Earth.
China confirmed in 2016 that it had lost contact with Tiangong-1 and could no longer control its behaviour, so we don’t really know where it will end up. The European Space Agency (ESA) said re-entry "will take place anywhere between 43°N and 43°S", which covers a vast stretch north and south of the equator.
Esa has given regular updates on Tiangong-1 and now estimates re-entry between 30 March and 2 April, but says this timeframe is "highly variable". The agency expects its forecasts will become more precise closer to the weekend.
科學家們監測到，一個已經失效的中國空間站的殘骸可能最早會於周五進入地球。
「天宮一號」是中國雄心勃勃的太空計劃的一部分，也是2022年載人空間站的原型。它於2011年進入軌道，五年後完成使命，之後預計將重返地球。
很難預測其返回地球的時間和地點，因為它不再受到控制。預計最遲於3月30日至4月2日之間重新進入大氣層。空間站的大部分可能會在大氣中燃燒，但有些碎片能夠殘留下來撞擊地球表面。
中國在2016年證實，已經與「天宮一號」失去聯繫，不能再控制它的行為，所以我們不知道它會在哪裡降落。歐洲航天局（ESA）表示，重返「將會在43°N和43°S之間的任何地方發生」，該地區覆蓋赤道以南和以北的廣闊地帶。
ESA定期更新「天宮一號」動態，現在估計在3月30日至4月2日之間重返地球，但表示這個時間框架「非常不穩定」。該機構預計接近周末時候它的預測將更加精確。