An international society of amateurs and professionals specialising in the observation of double stars and deep sky objects, founded in 1967.

Founded in 1892, is the oldest society of its kind in Australia. Its objectives are to promote the Science of Astronomy and all its branches by holding regular meetings and viewing nights, circulating current astronomical information, and encouraging popular interest.

Improves and promotes astronomical education at all levels in all institutions involved in teaching astronomy in Europe. Contains membership information, the group's history, news, newsletters and projects.

Professional and Amateur collection, research, and analysis of variable star observations.

Information useful and interesting to amateur astronomers, especially those located in Utah. Includes events, news, data and reference materials, and a weekly viewing conditions forecast. Has a special section about light pollution.

A project consisting of predictions and data for the moon, asteroids, and planets.

Key activities include research and observing planets, stars, celestial phenomena and the abatement of light pollution.

Founded in 1919, has a mission to promote and safeguard the science of astronomy through international cooperation. The organization is also the internationally recognized authority for assigning designations to celestial bodies and surface features on such bodies.

Promotes international interdisciplinary programs in solar-terrestrial physics, and organizes and coordinates such programs. Site has a newsletter, meetings and events, member directory, announcements, and links to related groups.

A network of volunteers have cameras focused on the sky to create a 360 degree map of the planets and stars at one time. Data is fed into a computer and filtered for atmospheric interference. Page includes details of the procedure, as well as a discussion forum.