University of Wisconsin
University of Wisconsin: The Constellations and Their Stars
An excellent site dedicated to the constellations and information about the objects which make them up. Contains a great deal of information about various stars, galaxies and other objects, as well as details on how best to observe them.
University of Wisconsin
Constellations and Their Stars: Andromeda
This site has factual information about Andromeda. Also contains other links.
NASA
Nasa Star Child: The Milky Way
The information, geared mainly for younger viewers, provides simple and basic information about the Milky Way, and includes several embedded links to related information.
University of Cambridge
University of Cambridge: Cosmology: Galaxies
This site from the Cambridge Relativity provides a brief description of the structure of the Milky Way galaxy. The parts described are the disc, bulge, and halo.
NASA
Nasa: Marshall Space Flight Center: Chandra
NASA's Chandra X-ray Observatory site features a photograph and explanation of a "cool" black hole in the Andromeda Galaxy (M31).
NASA
Nasa: Wilkinson Microwave Anisotropy Probe (Wmap): The Milky Way
Description of the three major components of the Milky Way galaxy as well as images and resources for further reading.