The student project’s Introduction and Conclusion give some information on how the expanding universe was discovered, and what logical steps lead from the Hubble diagram’s straight line to the expanding universe concept.

For more information on the expanding universe, its discovery, and the big bang theory, read the About Astronomy: Expanding Universe section of SkyServer, or see one of the following references:


Hartmann, William K., Astronomy: the Cosmic Journey, Wadsworth, 1989 Hawley, John F., Foundations of rd University Press, 1998

Web sites

An online guide to the Expanding Universe chapter of Hartman’s book is available; see the book for more details.