The Satellite Looks Down*

By now you've heard of the death at the age of 90 of Arthur C Clarke--see the New York Times' obituary here. Clarke is widely credited with popularizing the idea of space travel--see the trailer for the movie 2001: A Space Odyssey below--and numerous more specific technical concepts as well. In particular, his idea that satellites could be placed in fixed (ie, "geosynchronous") positions above the earth to allow for widespread communications. It turns out that these stationary positions are actually known as "Clarke orbits." You can read Clark's 1945 article detailing his idea here .--David E