Copernicus: Polish Cleric and Astronomer: Short biography of the man behind the heliocentric theory.
Encarta: Copernicus, Nicolaus: Encyclopedia article provides an overview of the astronomer's early life, his education, and his revolutionary theory that the earth was not the center of the universe.
Nicholas Copernicus: Short biography and sketch from PBS.
Nicolaus Copernicus: Detailed biography examines Copernicus' dissatisfaction with the Ptolemaic system of astronomy and his theory that the earth actually revolved around the sun. Also includes portrait.
Starchild: Nicolaus Copernicus: Introduces the father of modern astronomy.
The Scientists: Nicolas Copernicus.: Short biographical article includes links to articles on related topics.
Windows to the Universe: Nicholas Copernicus: Three short biographies geared toward beginning, intermediate and advanced readers. Includes links to related articles.