Milankovich cycles

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Milankovich cycles Cyclical changes in the rotation and orbit of the Earth that Milankovich correlated to climatic effects. There are three cycles: changes in the eccentricity of the Earth's orbit, altering the distance between Earth and the Sun at aphelion and perihelion, with a period of about 100 000 years; variations in the tilt of the Earth's rotational axis (obliquity of the ecliptic), with a period of about 40 000 years; and a movement (wobble) in the angle by which the axis of the Earth's rotation is tilted in respect of the orbital plane, altering the seasons at which aphelion and perihelion occur (precession of the equinoxes), with a period of about 21 000 years. Climatic changes associated with Milankovich cycles may be recorded in cyclic sedimentation.