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.