And here's the first class in the astronomy course. I like this guy because he writes such entertaining and fact-filled (as opposed to crap-filled, which we've all come to accept as normal for Web writing) articles about astronomy.
And he's the author of "Death from the Skies!" (The exclamation point is part of the title, not an indication of how excited I am to be reading about death from the skies.) (It's available from Amazon.com.)