NASA's Office of Space Science - a public information site with four main space science themes and corresponding sub-sites, Search for Origins, Structure and Evolution of the Universe, Exploration of the Solar System, and The Sun-Earth Connection

The National Space Science Data Center (NSSDC) - provides access to a wide variety of astrophysics, space physics, solar physics, lunar and planetary data from NASA space flight missions

NASA's Scientific and Technical Information Program - provides powerful search capabilities to over 3-million documents covering both the latest and most important historical information about aerospace, aeronautics and related topics

NASA's Human Spaceflight Web - information on  Space Shuttle missions, the International Space Station, and human spaceflight in general

Science @ NASA - from the Marshall Space Flight Center, NASA

Association of Universities for Research in Astronomy (AURA) - a consortium of educational and other nonprofit institutions that operates world-class astronomical observatories, dedicated to the advancement of astronomy and related sciences

Space Telescope Science Institute (STScI) - operated for NASA by AURA, STScI's electronic information service includes press releases and information on the Hubble Space Telescope (HST) and the Next Generation Space Telescope (NGST)

HubbleSite -- part of STScI, with sections on Discoveries, Sci•Tech, Edu•Space, Fun & Games, and a newly organized library of digital images by the Hubble Space Telescope

European Southern Observatory (ESO) - a multinational European organization for astronomical research headquartered in Garching, Germany, which operates the Very Large Telescope (VLT) array under construction on a mountain top in Chile

Chandra X-ray Observatory Center - an orbiting X-ray observatory launched in 1999 operated for NASA by the Smithsonian Astrophysical Observatory (SAO), with the latest X-ray images and a great public information section

The Solar and Heliospheric Observatory (SOHO) - a joint project of the European Space Agency (ESA) and NASA, SOHO operates an orbiting solar telescope which was launched on December 2, 1995

The SETI Institute - information about scientific research in the general field of Life in the Universe with an emphasis on the Search for Extraterrestrial Intelligence (SETI)

StarChild - NASA's learning center for young astronomers

The Eight Planets - a multimedia tour of the solar system

Windows to the Universe - an educational site for all levels of seekers, a NASA-funded project hosted by the University of Michigan

Amazing Space - a set of web-based activities primarily designed for classroom use, but made available for all to enjoy, from the Space Telescope Science Institute

The Light Cone - an illuminating introduction to relativity, from the physics department of Syracuse University 

Cosmology - A Research Briefing - an overview of modern cosmology presented by The National Research Council, Board on Physics and Astronomy

The Quarks to Quasars Story - from Fermi Lab, describing the ideas, tools, and research methods used by particle physicists

A Virtual Space-Time Travel Machine - a great source of graphics for the visualization of mathematics and physics, operated by France's Ecole Polytechnique

Contemporary Physics Education Project - a nonprofit organization comprised of leading physicists and outstanding teachers and educators; an excellent site including an interactive tour of the inner workings of the atom

The Living Earth, Inc - images of our planet and current articles of interest, and a source of high-quality satellite images of the Earth for commercial and educational interests

StarDrive - fostering increased public awareness and education in the theoretical and technological aspects of interstellar travel

The 2001 Principle - re-examines and attempts to re-validate the classical 'Argument from Design' using the concept of Cognitive Dissonance and audience reaction to the film '2001 - A Space Odyssey'

AIRES:  New Medical Technologies Foundation BIP International Association Research Center (U.S. mirror site) - presents a theoretical model and applications of BIP (Bio-Energetic Programming) technology, a technique for programming information interrelations which determine the fundamental base of a biological entity; AIRES is a nonprofit organization primarily oriented at facilitating and promoting healthcare, science and culture, and environmental protection development