AP

The Modern View of the Cosmos

• Bauer, H.H. (1992). Scientific Literacy and the Myth of the Scientific Method. Urbana and Chicago: University of Illinois Press.
• Cox, A.N., ed. (1999). Allen's Astrophysical Quantities. (4th ed.). New York: Springer.

The Hertzsprung-Russell diagram - usually referred to by the abbreviation H-R diagram - is a diagram that illustrates the properties of stars. As stars progress through their lives, they move around on this diagram since their properties change over time.