The march of the seasons—winter, spring, summer, and fall—stems from the "clearly definable" position of the sun on the summer and winter solstices, according to Judith Young, a professor of astronomy at the University of Massachusetts in Amherst.

"The solstices are very accurately measured as the northernmost point that the sun rises along the horizon in June and the southernmost point along the horizon in December," she said. "It doesn't matter where you are on Earth—that's true."

This regularity allowed for the construction of Stonehenge in England some 5,000 years ago, where sunrise on the summer solstice is still celebrated with fervor.

(Related: "Wooden 'Stonehenge' Emerges From Prehistoric Ohio.")

In modern times, the solstice points became the astronomical definitions of when the summer and