Astrophysics (Index)About


(occurring slowly over a long period of time)

Secular, as used in astronomy, indicates occurrence over a long period of time and not periodic. It is especially used to discuss the long-term trends in a motion that is periodic over the shorter term, such as stating that/how an orbit changes over time. The term is commonly used in describing dynamics and orbits. Some phrases:

The term is also used in time series analysis, with an analogous meaning.

Further reading:

Referenced by pages:
celestial mechanics
gravitational instability (GI)
Jacobi integral
Laplace-Lagrange secular theory
orbital resonance
perturbation theory