But, The Guardian says, we don’t have to worry about death by 8.5 tons of space junk – probably:
China’s space agency has since notified the UN that it expects Tiangong-1 to come down between October 2017 and April 2018.
Since then the station’s orbit has been steadily decaying. In recent weeks it has dipped into more dense reaches of Earth’s atmosphere and started falling faster.
“Now that [its] perigee is below 300km and it is in denser atmosphere, the rate of decay is getting higher,” said Jonathan McDowell, a renowned astrophysicist from Harvard University and a space industry enthusiast.
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Although much of the craft is expected to burn up in the atmosphere, McDowell says some parts might still weigh up to 100kg when they crash into the Earth’s surface.
The chance that anyone will be harmed by the debris is considered remote but China told the United Nations “Committee on the Peaceful Uses of Outer Space” in May that it would carefully monitor the craft’s descent and inform the United Nations when it begins its final plunge.
Predicting where it is going to come down would be impossible even in the days ahead of its landing, McDowell said.