TEMPO overpass time predictions: =============================== Prediction cadence: ------------------- TEMPO overpass predictions are normally generated every Monday, at the same time as the weekly command load. The predictions cover a seven day period from Thursday when the new command load is activated, until the following Thursday when the next command load is activated. The typical scan pattern has hourly revisits during mid-day, with more frequent revisits of areas with better illumination during sunrise and sunset. Occasional gaps in the scan pattern occur when TEMPO scanning is interrupted by a spacecraft station-keeping maneuver. File format: ----------- Overpass prediction files are in netcdf4/HDF5 format, with filenames of the form: tempo_overpass_s_e_c.nc where the timestamps embedded in the filename give: 's' = the UTC start time of the prediction interval, 'e' = the UTC end time of the prediction interval, 'c' = the UTC time when the prediction was generated. Each prediction file contains a table of overpass times for each ground site in the file 'site_list.csv'. Each ground site's 'shortname' is used to name file group containing the overpass times for that site. Each netcdf4 prediction file is accompanied by a PDF file containing human-readable timetable plots. Assumptions: ----------- The overpass predictions assume that the host spacecraft is located at its nominal orbital station, and that the TEMPO instrument has its nominal boresight aim point. As long as the actual orbital position and aim point are within typical variations, the predicted overpass times should be accurate to within about +/-30 sec, with errors smallest for scan positions near the nominal aim point.