Orbital Dynamics, Climate Change, and Leap Years: Beyond the Gregorian Calendar

"Earth's orbit creates more than a leap year" Astronomy Report (February 13, 2008)

This post isn't as technical as the introduction, with its "parameters such as planetary gravitational attractions, the Earth's elliptical orbit around the sun and the degree of tilt of our planet's axis with respect to its path around the sun, have implications for climate change and the advent of ice ages."

This is a pretty good introduction into the sort of changes this Earth has gone through: and that "nothing endures but change."

(We've already had that calendric rarity, February 29. But, since there are still nearly ten months left in this leap year, I feel justified in posting more that the usual number of year-orbit-and-date-related links.)