MIT's Magazine of Innovation.
Exploration, exhibits, cosmology, quantum physics.
Discovery Channel OnLine. Science, expeditions, more.
New Scientist reports, explores and interprets the results of human endeavour set in the context of society and culture.
The Public Broadcast System. History, science, arts, TV schedule.
The Learning Channel OnLine.
Sky & Telescope
Sky and Telescope OnLine. Good tutorial on telescopes.
Astronomy Magazine OnLine.
Society of Popular Astronomy
Based in London.