The Astronomy Picture Of the Day is the website run by Robert Nemiroff and Jerry Bonnell. They're a couple of awesome space geeks, and they both have a bunch of material other than this site that's worthy of your eyeball time.

The site has a calendar with thumbnails of all the past APODs... surf and learn. It's guaranteed to consume at least 3 hours of your netTime, if you're into this kind of thing.

Find APOD @: http://antwrp.gsfc.nasa.gov/apod/astropix.html

since both are likely search keywords, check more info at: APOD