Earth & Cosmos / Earth, Climate & Environment

Milankovitch orbital cycles

Milutin Milanković calculated how Earth's orbit shifts sunlight over tens of thousands of years, pacing the ice ages (1941).

The Serbian engineer and mathematician Milutin Milanković used celestial mechanics to calculate how changes in Earth's orbit shape, axis tilt and wobble alter summer sunshine at high northern latitudes, and published the full theory in 1941. His cycles of roughly 21,000, 41,000 and 100,000 years were confirmed in 1976 by deep-sea sediment records (Hays, Imbrie and Shackleton). They explain when ice ages begin and end and are the baseline for judging today's warming.