The Milankovitch Cycles are the results of studying past global climate changes over millions of years. One of the causes in climate change is precession of the equinoxes, which seems to have a period of 22,000 to 23,000 years, over millions of years.

But according to the current accepted model of precession, the main source of precession is due to luni-solar forces and slowly increases (period decreases), has done so for who knows how long, and will continue to do so. In fact, from 1900 to 1975, Simon Newcomb’s formula for precession below was used to calculate the yearly increase in precession.

50.2564 + .000222 (year – 1900)

Note the table, below using Newcomb’s annual increase, 100,000 years ago, precession would have been around 28 arcsec/year for a corresponding period around 46,000 years – definitely out of sync with the Milankovitch cycle. And the further back we go in time, the greater the discrepancy.

Additional information on this topic can be found at:

http://www.doc.mmu.ac.uk/aric/gccsg/2-4.html
http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm