Three nations have the responsibility to pay compensation in case any one gets hurt when the 2.4 ton ROSAT X-ray telescope crashes to the Earth. ROSAT's re-entry to the atmosphere is expected to happen sooner, between October 20 and October 25, not November as earlier predicted due to enhanced solar activity.

And in case anyone gets injured by the telescope's debris, which has a 3000 to 1 chance, three nations have the responsibility to pay compensation. According to the DLR, the German laboratory in charge of the mission, the three countries are the U.S. which launched the project, the UK where the primary payload was made, and Germany which ran the mission.

According to Johann-Dietrich Worner, executive director of DLR, the German laboratory in charge of the mission, the increased solar radiation activity has enlarged the atmosphere, increasing the friction on the satellite which will cause it to come down earlier than expected. The DLR, however, cannot predict the date range the satellite is most likely to deorbit as it depends on fast-fluctuating atmospheric conditions.

More mass of the satellite is expected to survive re-entry compared to the UARS satellite. "If the core of ROSAT withstands reentry then a 1.6 ton piece could hit the Earth. But it's more probable that parts in the mass range of hundreds of kilos will result," Worner said.

The US Strategic Command and the European Space Agency is tracking ROSAT's activity and will issue warnings within five hours of impact if populated areas seem at risk.