#Greenwich_Mean_Time__Greenwich_Time__GMT__universal_time__universaltime__ut__UT1  the local time at the 0 meridian passing through Greenwich, England; it is the same everywhere
  supertype:  time  the continuum of experience in which events pass from the future through the present to the past
  subtype:  universal_time_coordinated__UTC__utc  Greenwich Mean Time updated with leap seconds
     subtype:  Earth-received_time__ERT  the universal time coordinated when an event is received on Earth
     subtype:  transmission_time__TRM  the universal time coordinated time when a transmission is sent from Earth to a spacecraft or other celestial body
     subtype:  spacecraft_event_time__SCET  the universal time coordinated time on board the spacecraft; "SCET = TRM + OWLT"

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