Learn about the vernal equinox by completing this web hunt.

This site, created by an amateur who has studied astronomy for thirty years, provides a scholarly explanation of the vernal equinox. Links to definitions of significant terms.

Find out what the seasons are and how they change. Through the use of excellent graphics, content explores the Earth's orbit around the sun and how sunlight reaches the earth at equinox and the winter solstice.

This Montana State University site provides a simple chart on the spring and fall equinox and a description of the process.

[Free Registration/Login Required] This flipchart explores the relationship between the sun and earth and how the seasons happen. Vocabulary of the equinox, solstice, etc. is included.

Learn about the four seasons, when they occur in the northern and southern hemispheres, and why the seasons change as the Earth rotates around the Sun.