Policy:  Expert Review

Authority:  CCSDS.MOIMS.NAV

OID:  1.3.112.4.X.1

References:



" " Details Status Value Description and Reference Nomenclature isDefault Units/Type OID
GPSZ GPS time expressed as elapsed time since the GPS epoch of 6 January 1980 00:00:00:00 UTC. The elapsed time is presented in terms of Z counts (1.5 second increments) (578217609.333). Note that this differs from normal GPS convention where the Z count is represented as the number of whole weeks since the GPS epochs and the number of 1.5 second increments into the week. N/A 1.5s increments 1.3.112.4.X.1.1
TDB Barycentric Dynamical Time (TDB) is intended to serve as the independent argument of barycentric ephemerides and equations of motion. It is defined as being linearly related to Barycentric Coordinate Time (TCB) The linear relationship between TDB and TCB is chosen such that the rate of TDB closely matches TT for the time span covered by the JPL Development Ephemerides. TDB is sometimes designated as Barycentric Ephemeris Time (Teph) when used as the time scale of the JPL ephemerides. N/A N/A 1.3.112.4.X.1.2
UTC Coordinated Universal Time (UTC) is a broadcast time standard providing both astronomical time of day and atomic-time interval. UTC is kept within +/-0.9 s of UT1 by the introduction of leap seconds and is therefore a legally recognized proxy for Universal Time in most countries. UTC is always offset from TAI by an integer number of seconds, and is thus a carrier of precision frequency and time interval for broadcast standards based on the SI second. Note: Zulu time is synonymous with UTC. N/A N/A 1.3.112.4.X.1.3


Time System Relationships

Technical References