A third measurement was sucessfully carried out on 11 December but did not improve the accuracy of the prediction. However, it gave indications that the remaining lifetime might be at the upper end of the measurement accuracy, i.e. up to the beginning of May 1998. Having completed the analysis of this data, various fine tunings were made to the system. The absolute pointing error has been reduced to less than 1.5 arc seconds. ISO's pointing performance Units Spec.
Satellite is in excellent condition.
Over the course of time, the westward motion will slowly decrease and reverse. Mission Planning The Mission Planning system within the SOC is routinely producing and executing very efficient scheduled of highly-graded observation. ISO averages around 40 observations a day and carries out about 400 hours of science observations per month. Version 6.2 of the pipeline, containing many minor updates, was first used for processing with revolution 691 on 10 October. Version 6.1 of the pipeline became operational on 1 August 1997 and, compared to 6.0, had better reconstruction of the pointing information for observations made between revolutions 79 and 451.