USO should be ON and scheduled in the background (TO BE SCHEDULED BY SOC AT PLANNING SET-UP). HAA should be in CONFIGURATION mode and scheduled in the background (TO BE SCHEDULED BY SOC AT PLANNING SET-UP). If HAA is OFF, HAA needs to be ON at least 48hours before measurement starts. Latitudes should be repeated at regular intervals to characterize evolution of wave phenomena and middle-atmospheric temperatures. Occultation observations are event-driven and defined by the Earth-SC line reaching the '1-bar level plus 1000 km'. Note that the occultation event shall include a 1-hour margin at the beginning and at the end to serve as a baseline for radiometric measurements. Note that USO UNMUTE command should be 4 hours before the start of the occultation event. This observation should be preceded by 3GM_HAA_SELF_CALIBRATION 1 hour before the start of the occultation event.
any rule that is used to schedule the observation: repetition rules, continuous (plasma instruments), one-off, every orbit, every day, etc