LITTLE KNOWN FACTS ABOUT EPOCH SIGN IN.

Epoch compared to equinoxDate-references for coordinate systemsEpochs and periods of validityChanging the normal equinox and epochSpecifying an epoch or equinoxBesselian yearsJulian years and J2000Epoch from the daySee alsoReferencesNotesCitationsSourcesFurther readingExternal one-way linksAstronomical quantities can be laid out in any of a number