Astronomy & Astrophysics

• NASA Home Page
  An enormous site with links to data generated by NASA sponsored missions, to images, and to other NASA sponsored research sites.
• U.S. Naval Observatory Astronomy Data Services
  Links to data about sunrise, sunset, phase of the moon, eclipses, daily positions of the sun and moon, and more.
• Planetary Image Atlas
  Data and images from NASA sponsored missions.

European Southern Observatory (ESO)