German scientists say they expect pieces of a defunct satellite hurtling toward the atmosphere to hit Earth this weekend.
Andreas Schuetz, a spokesman for the German Aerospace Center, said Friday the best estimate is still that the ROSAT scientific research satellite will impact sometime Saturday or Sunday.
The center says parts of the minivan-sized satellite will burn up during re-entry but up to 30 fragments weighing a total of 1.87 tons (1.7 metric tons) could crash into the Earth with a speed of up to 280 mph (450 kph).
The satellite orbits the Earth every 90 minutes and scientists can only say that it could hit Earth anywhere along its path, between 53-degrees north and 53-degrees south - a vast swath of territory that includes much of the planet outside the poles.
Explore further: New NASA Van Allen Probes observations helping to improve space weather models