Epoch (astronomy)

In astronomy, an epoch is a moment in time uised as a reference pynt for some time-varyin astronomical quantity, such as the celestial coordinates or elliptical orbital elements o a celestial body, acause these are subject tae perturbations an vary wi time.[1]


  1. Soop, E. M. (1994). Handbook of Geostationary Orbits. Springer. ISBN 978-0-7923-3054-7.