The Sun's Rotation Period Derived from Recurrent Sunspots, 1924–1933

Abstract

In this activity, students learn how sunspots can be used to determine the rotation period of the Sun. They are asked to theorize on possible reasons for the Sun's apparent motion, and to use an overlay to determine solar latitude and longitude and photographs of sunspots to help them perform measurements to determine the rotation period of the Sun. The overlay, photos of sunspots over a period of four days, and a student worksheet are provided. Educational levels: Middle school