Experts tracking China's defunct Tiangong-1 space lab say it could now fall to Earth later than thought. The analysis had suggested the 10m-long, 8.5-tonne spacecraft would plunge into the Earth's atmosphere between midday Saturday and the afternoon of Sunday (GMT) - and it still could. But the most recent assessment has extended the estimated window for re-entry. It now goes out to the late evening of Sunday, 1 April. The situation remains highly variable.
China lost all contact with, and control over, Tiangong in 2016. When it does eventually dive back into the atmosphere, it will break up. However, the chances of any debris hitting a populated area on the ground are described as very slim.
"Given Tiangong-1 has a larger mass and is more robust, as it is pressurised, than many other space objects that return uncontrolled to Earth from space, it is the subject of a number of radar tracking campaigns," explained Richard Crowther, the UK Space Agency's chief engineer. The majority of the module can be expected to burn up during re-entry heating, with the greatest probability being that any surviving fragments will fall into the sea," he told BBC News.