The Sun

Studying the Sun has given you knowledge about the most massive body in the Solar System. When you began this topic, you may have thought of the Sun as a large ball of hydrogen and helium gas held together by gravity. But really, the Sun is made up of different layers, each with its own defining characteristics. The Sun is also violent, with sunspots, occasional eruptions, and coronal mass ejections.

The Sun has always supported the existence and the continuation of life on the Earth. Throughout time, the amount of knowledge about the Sun has drastically improved and continues to improve day by day.  The Sun will continue to produce energy through nuclear fusion for billions of years. When all of its hydrogen has turned into heaver elements, it will begin the end of its life cycle as a star.

Extend Your Learning

In this topic, you explored the phenomena known as the aurora borealis. This spectacle, which can appear over the northern United States during the winter months, is breathtaking and has provided inspiration for many poems, stories, songs, and other works of art. Members of the Menominee Indian Tribe have lived in areas of what is Wisconsin, Illinois, and Michigan for over 10,000 years. They have been observing natural wonders for nearly as long. In his 1888 book about the Menominee Indian Tribe, Walter J. Hoffman recorded the following Menominee folk tale associated with theaurora borealis:

In the direction of the north wind live the manabai'wok (giants), of whom we have heard our old people tell. The manabai'wok are our friends, but we do not see them anymore. They are great hunters and fishermen, and whenever they are out with their torches to spear fish we know it, because then the sky is bright over the place where they are.