| Description: This attribute is intended to be used as a column in a table. observed_event_time_utc indicates the UTC time corresponding to the instant at which photons were received at the instrument. In a label the corresponding values may be given by the optional start_observed_event_utc and stop_observed_event_utc attributes (or the corresponding values using Barycentric Dynamical Time, _tdb). At least one of either observed_event_time_utc or observed_event_tdb, must be a table field for occultation data. Both may be used. observed_event_time is equivalent to spacecraft_event_time for spacecraft data and to earth_received_time for Earth-based data. It is always the photon arrival time, so in this regard we treat typical spacecraft radio occultation data as Earth-based, referring to the time at the DSN receiving station. For an uplink radio occultation, this is the spacecraft event time. |