The Earth's Tilt Actually Changes From Time To Time

The tilt of the Earth does, one of the interesting facts about Earth, change through time, despite popular belief. Oblivion, also known as obliquity, has changed during the past million years between 22.1 and 24.5 degrees in relation to Earth's orbital plane. Since each hemisphere receives greater solar energy throughout its summers, this has a significant impact on the Earth's temperature and seasons. The opposite is true of its winters.

This was shown to be one of the primary factors influencing changes in Earth's climate over time by the late Serbian mathematician, astronomer, climatologist, and geophysicist Milutin Milankovitch (the melting and retreat of glaciers and ice sheets).

The tilt of the Earth's axis is currently 23.4 degrees. That falls about in the middle of its two historical extremes. In a roughly 41,000-year cycle, this angle is progressively decreasing. Although its occurrence is well known in the planetary and climatic sciences, scientists still don't fully understand why it occurs.