Eastbay Astronomical Society
Astronomical Society of the Pacific
Astronomical Association of Northern California
American Astronomical Society
International Astronomical Union Headlines
SKY Online is a service of the publishers of Sky and Telescope and CCD Astronomy magazines.
Planetaria on the World Wide Web
List of local amateur astronomy clubs
The Planetary Society , devoted to encouraging human exploration of space.
Searchable directory of astronomy and related organizations.
The Northwest Group of Astronomical Societies in Britain.