Galaxies, Stars, Telescopes

Cosmology - The Study of the Universe: from the WMAP (Wilkinson Microwave Anisotropy Probe) project's website.
Virtual Trips to Black Holes and Neutron Stars: Movies in "mpeg" format, computer simulations that take you on virtual trips into strange and unfamiliar worlds.
American Association of Variable Star Observers: A worldwide community of amateur and professional astromoners who are interested in studying variable stars.
The General Catalogue of Variable Stars: The General Catalogue of Variable Stars, from the Sternberg Astronomical Institute in Moscow, Russia.
The Internet Stellar Database: A searchable database containing extensive information about most major stars within 75 light-years away from Earth.

HubbleSite: The latest news, photos, and facts from the Hubble telescope.
The European Southern Observatory Homepage: The ESO has telescopes in South America, and is headquartered in Europe. This is their homepage, and it has extensive resources available, including photographs, reports, and news.
Space Telescope Science Institute: Astronomy Resources from STScI - including the Hubble Deep Field (HDF), the Hubble Ultra Deep Field (UDF), The Great Observatories Origins Deep Survey (GOODS), Spitzer Infrared Nearby Galaxies Survey (SINGS), plus more.
Global Oscillation Network Group: The Global Oscillation Network Group studies the interior of our Sun using a global network of six imagers.
Mauna Kea Observatories: From The University of Hawaii Institute for Astronomy's website, this is the homepage for the Mauna Kea Observatories, providing information about each of the telescopes located there.