A defunct German space telescope is set to collide with Earth less than five weeks after a satellite the size of a bus hits the planet.
The 2.4-ton Röntgensatellit, or ROSAT, has been spinning aimlessly through space for 12 years after it was switched off in 1999 after its guidance system broke.
With its orbit bringing it inexorably closer to Earth, the authorities initially thought it would burn up entirely on re-entry.
However, it is now believed that pieces of space junk weighing up to 400kg could smash into the planet’s surface as early as the end of October.
And experts warned that ROSAT would not be the last to hit because solar activity next year is likely to damage far more ageing spacecraft and send them plummeting to Earth.
ROSAT’s pieces are almost three times heavier than the biggest chunk of UARS, the US satellite which is expected to strike within the next 24 hours.