Some Astronomy Related Stuff
NASA / JPL
Mars Exploration Rover Mission (Spirit & Opportuniy)
Cassini-Huygens Mission to Saturn
NASA Jet Propulsion Laboratory Home Page
NASA RP 1383: Total Solar Eclipse of 1998 February 26
NASA Space Shuttle & Space Station Web Archives
The NASA Astrophysics Data System
Educational
Bad Astronomy (I love this site!)
Martindale's Calculators On-Line Center
Publications / Societies