Introduction

Understanding why the Earth has seasons is one of the most difficult concepts for students to understand, and it is often a battle to get them to abandon their preconceived ideas. Two widely held misconceptions are:

• Earth's orbit brings it closer to the sun in summer and farther away in winter. This idea neglects the fact that at any given time the Northern and Southern Hemispheres experience opposite seasons. In fact, earth's orbit is actually nearly circular, and so variations in distance from the sun have little effect compared to the effects of changes in the angle of incoming sunlight.
• The hemisphere that is tilted toward the sun experiences summer because it is closer to the sun. Actually, earth is so small compared to the sun, and so far away from it, that the difference in distance between the two hemispheres and the sun is inconsequential. However, the tilt of earth's axis does affect the angle at which the sun's rays strike earth—called the angle of incidence—this is what causes the seasons.

Interviews with Harvard graduates in the late 1980s illustrate how widespread these misconceptions about the seasons are. When asked what causes the seasons, most of the newly graduated students gave the same wrong answer that many people give: the seasons are caused by earth getting closer (or farther) from the sun. The section on Misconceptions of this publication provides a wealth of resources that will help you understand, uncover, and change your students’ preconceived notions of the seasons and other science concepts.

We have also included classroom activities in which students use real-time data and their own observations to explain why the seasons change as well as resources that talk about how different cultures over the millennia have explained the changing of the seasons.

---

 Back to top

Copyright June 2007 — The Ohio State University. This material is based upon work supported by the National Science Foundation under Grant No. 0424671. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

This work is licensed under a Creative Commons License.