The Physics To Go website will be unavailable Friday evening through Saturday afternoon as electrical work occurs in the American Center of Physics server room. Down time will begin at 6PM Eastern Time on Friday. Service is expected to resume by 6PM on Saturday, July 30.
This site, from Cornell University, is terrific! You can find out about the great ideas in astronomy, astrophysics, and cosmology through a series of short, well-illustrated descriptions. To learn more, you can use "Ask an Astronomer," which has an archive of past questions, with answers labeled beginner, intermediate, or advanced. You'll also see a nice image on the front page, and these are also archived.
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