Space Telescope Science Institute

National Optical Astronomy Observatories

National Radio Astronomy Observatory

Cerro Tololo Interamerican Observatory

Kitt peak National Observatory

National Solar Observatory

United States Gemini Program

Harvard - Smithsonian Center for Astrophysics (CfA)

ROSAT

AXAF

Fred Lawrence Whipple Observatory

Multiple Mirror Telescope Observatory

W. M. Keck Observatory

Mauna Kea Observatories

Canada-France-Hawaii Telescope

James Clerk Maxwell Telescope

Berkeley Illinois Maryland Association (BIMA)

Haystack Observatory

European Southern Observatory (ESO)

Anglo-Australian Observatory

Institut de Radio Astronomie Millimétrique (IRAM)