Satellite Predictions

The official ILRS format for satellite predictions is the Consolidated Prediction Format (CPF). This newer CPF is the operational format for prediction providers and network stations as of June 30, 2006. Prior to this time, predictions were provided in the Tuned Inter-Range Vectors (TIRVs) format.

The Consolidated Prediction Format (CPF) accurately predicts positions and ranges for a much wider variety of laser ranging targets than had been previously possible. Rather than using the "Tuned IRV's" with an integrator, the new predictions will provide daily tables of x,y, and z positions for each target that can be interpolated for very accurate predictions. CPF provides an expanded format capability and should greatly improve tracking on low satellites because the full modeling potential of the orbit computation at the prediction center will be passed on to the stations. Drag files and special maneuver files will no longer be necessary. These predictions are available via email (i.e., predictions exploder) or via anonymous ftp from the data centers (CDDIS, EDC) and/or the prediction centers. If you would like to be added to the predictions distribution list contact Carey Noll (

When SLR tracking is not possible because of satellite anomalies (e.g., going into safe hold mode, etc.) the mission contacts are required to inform the stations of this abnormal situation by sending a short message to the URGENT email exploder. A follow-up message when the satellite returns to normal status should also be sent to the URGENT exploder. Mission contacts can provide more details about the satellite configuration and status directly to the stations using stations exploder.

CPF prediction files issued before a planned maneuver and covering the epoch of the maneuver should contain the post-maneuver arc based on predicted values for the thrusts. A warning message announcing the maneuver (satellite name, time of the planned maneuver) should be sent to the URGENT email exploder.

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