11: The Four Seasons - Two Competing Models
- Page ID
- 25252
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The change of the seasons through the year are one of the more obvious, and more puzzling aspects of our world. Throughout history there have been many theories as to how and why the seasons change in regular cycles as they do – some of these were quite insightful, others were simply preposterous. We will take a look at two competing theories, one is actually correct, and the other is a very common scientific misconception, mistakenly believed by a great many people! Your students will use the skills they have learned about building a model, playing with it, seeing what predictions the model makes, and then comparing these predictions with actual observations in order to decide which model is correct!
- 11.1: The Elliptical Model of the Seasons
- The elliptical model of the seasons predicts that the elliptical planetary orbits discovered by Johannes Kepler are indeed the cause of the seasonal changes. In this model, the Earth’s axis stands perpendicular to its path in orbit, and the change in distance from the Earth to the Sun causes the change in the weather of the seasons as we move through the year. Our ping-pong models of the Earth, Moon, and Sun from Activity #23 are built on this premise.
- 11.2: The Tilted Axis Model of the Seasons
- Copernicus was the first modern scientist who discussed how the tilt of the Earth’s axis fitted into a scientific model of the solar system. It wasn’t until Tycho Brahe made extremely precise measurements of the position of the Sun, Moon, and planets in the sky and Johannes Kepler put those observations into the context of an exact mathematical model that we understood, and measured, the tilt of the Earth’s axis with modern precision.