Space:

• http://www.astro.wisc.edu/~dolan/constellations/
  (Constellations and their Stars)

Planets:

• http://www.seds.org/nineplanets/nineplanets/nineplanets.html
  (Tour of the Solar System)

• http://pds.jpl.nasa.gov/planets/  
  (Welcome to the Planets)

Agencies:

• http://www.nasa.gov/ (NASA)

Astronauts:

• http://www.jsc.nasa.gov/Bios/astrobio.html (Astronaut Biographies)

Exploration:

• http://oposite.stsci.edu/pubinfo/pictures.html
  (Hubble Space Telescope Public Pictures)

• http://sln.fi.edu/tfi/programs/g-scouts/space1.html
  (Rockets - History & Science)