After the UARS, the world is bracing for the next big satellite that is about to fall to the Earth, the 2.4 ton ROSAT X-ray telescope.

Although not as massive as the UARS, the German Aerospace Center believes that considering its structure, an estimated 30 pieces totaling 1.6 tons of the telescope could survive re-entry, compared with the 26 pieces or a half-ton for UARS.

In its latest update, the German Aerospace Center said that the largest single fragment that could fall is the telescope's mirror which reportedly weights 1,700 lbs or 785 kilograms.

However, as with the UARS, it cannot be pinpointed as to when and where the satellite will fall.

The Canadian Press has quoted Phil Langill of the University of Calgary, the chance of any piece hitting any person was about 1 out of 2,000, compared to 1 out of 3,200 for UARS.

Initially projected to make its re-entry in early November, German space officials now estimates that ROSAT will make its atmospheric re-entry at any time from Oct. 20 to 25. The change was due to new data and changes could still be expected in the days to come.

The U. S. Space Surveillance Network and a radar facility near Bonn, Germany are tracking down the activity of ROSAT.

ROSAT, which stands for "Roentgen Satellite," is a German-U.S.-British mission that was launched in 1990 from Cape Canaveral Air Force Station in Florida to conduct an all-sky survey in X-ray wavelengths, cataloging more than 150,000 objects.

The mission was called off in 1999 after mission managers have lost control, which thus resulted to the uncontrolled re-entry of the bus-sized spacecraft to the atmosphere.