National Optical Astronomy Observatory -- Information, news, resources, outreach programs, gallery, observing information, software, and newsletter & reports. Visit

Spitzer Space Telescope -- General information, articles, downloads, equipment information, news, and links. Visit

Lowell Observatory -- Research, education & outreach, mission, star tales, and links. Visit

InfraRed Telescope Facility -- General information, observing information, instrumentation, facility systems, photo gallery, news, and links. Visit

Sloan Digital Sky Survey -- A dedicated 2.5 meter telescope which uses sensitive electronic light detectors to systematically map a ¼ of the sky, building a catalog of celestial objects, galaxies, and quasars. Data links, questions & answers, image gallery, project tour, news, archive, publications, and links. Visit

Keck Interferometer -- A ground-based component of NASA's Origins Program that addresses fundamental questions about the formation of galaxies, stars, and planetary systems, the prevalence of planetary systems around other stars, and the formation of life on Earth. Visit

McDonald Observatory -- Facility information, equipment & instrumentation, observer information, & research. Visit

Steward Observatory -- Equipment information, projects, calendar, talks, news, and links. Visit

Cambridge Optical Aperture Synthesis Telescope -- A multi-element optical interferometer with baselines of up to 100 meters, designed to observe stars with angular resolution as high as one thousandth of one arcsecond. Visit

Carnegie Observatories -- Information for observers, calendar, publications & libraries, seminars & conferences, fellowship program, & links. Visit

Mount Laguna Observatory -- Facilities, equipment & instrumentation information, virtual tour, site map, CCD camera laboratory & production, & resources. Visit

The Advanced Satellite for Cosmology & Astrophysics -- Mission characteristics, science highlight, and archive. Visit

Stratospheric Observatory for Infrared Astronomy -- News & updates, education & public outreach, research information, & galleries. Visit

Mount Wilson Observatory -- Projects, outreach & education, history, FAQ, news, and links. Visit

Kitt Peak National Observatory -- General information, image gallery, facility schedule, documentation, observation information, documentation, & electronic forms & tools. Visit

Tenagra Observatories -- Operations, commercial time, facilities & equipment information, sites, discoveries, articles, and links. Visit

Berkeley Automated Imaging Telescopes -- Information for the Leuschner Berkeley & the Katzman automatic imaging equipment. Visit