EUROPEAN SPACE AGENCY
EUROPEAN SPACE OPERATIONS CENTRE
GROUND SYSTEMS ENGINEERING DEPARTMENT
Space Debris Office
CLASSIFICATION OF GEOSYNCHRONOUS OBJECTS
This is a status report on geosynchronous objects as of the end of 2007. Based on orbital data in ESA's DISCOS database the situation near the geostationary ring (here defined as orbits with mean motion between 0.9 and 1.1 revolutions per day, eccentricity smaller than 0.1 and inclination below 30 deg) is analysed. From 934 objects for which Two-Line-Elements (TLE) are available, 318 are controlled inside their longitude slots, 462 are drifting above, below or through GEO, 148 are in a libration orbit and 6 whose status could not be determined (status of Dec. 2007). Furthermore, there are 47 controlled satellites and 166 uncontrolled objects without TLEs (of which 67 have not been catalogued) and 3 with indeterminate status. Thus the total number of known objects in the geostationary region is 1150, out of which 365 are controlled, 776 are uncontrolled and 9 could not be classified. Additionally there are 143 orbits listed in this report for unidentified objects. Some of those belong to objects where no recent TLEs are available but which are already included in the total number of 1150.
During 2007 thirteen spacecraft reached end-of-life. Eleven of them were reorbited following the IADC recommendations. One spacecraft was reorbited with an insufficient increase in altitude and only one spacecraft was abandoned without an end-of-life reorbiting manoeuvre.
Ten years after the IADC GEO reorbiting guidelines were established, it seems that they are now commonly applied with few exceptions.
If you detect any error or if you have any comment or question please contact
Dr R. Jehn
European Space Operations Center
64293 Darmstadt, Germany