Here is a collection of Internet links to facilities on, or related to, the Mt. Wilson Observatory complex. Don't let the age of many of the Observatory's facilities fool you. These old telescopes remain among the world's best. And they are being joined by a new generation of instruments under construction even now. Mt. Wilson Observatory remains one of the world's foremost centers of astronomical research.

• Mt. Wilson Observatory
  Founded December 20, 1904
  
  
• The 60-inch Telescope
  The first of the large telescopes on the mountain. The mirror was installed in the telescope on December 7, 1908. First light December 8, and the first photographs taken December 20. It eclipsed the Yerkes 40-inch refractor as the world's largest operating telescope.
  
  
• The 100-inch Hooker Telescope
  The Hooker Telescope eclipsed the 60-inch as the world's largest telescope. The mirror blank arrived in Pasadena on December 7, 1908, the same day the 60-inch mirror was installed on the mountain. The finished mirror arrived on Mt. Wilson July 1, 1917, and was installed in the telescope on September 22. First light was November 1/2, 1917. It remained the world's largest telescope until 1948 when the 200-inch Hale telescope at Palomar was completed.
  
  
• The Snow Solar Telescope
  The first solar telescope on Mt. Wilson; first solar photographs on April 11, 1904. Its horizontal construction presented problems that prompted the vertical tower construction of the 60-foot and 150-foot telescopes.
  
  
• The 60-foot Solar Tower Telescope
  First used while still under construction in 1907. Observations made on June 26, 1908, after the telescope was completed, showed unambiguous evidence for a magnetic field on the sun. This was the first observation of an extraterrestrial magnetic field. The 60-foot tower was the world's most sensitive solar telescope in its day. Currently used for studies in helioseismology.
  
  
• The 150-foot Solar Tower Telescope
  The tower construction was finished in 1910, and observations began in 1911. The 150-foot tower eclipsed the 60-foot tower as the world's most powerful solar telescope, and remained so until the completion of the McMath Solar Telescope in 1962. Currently used for studies in high-resolution spectroscopy, magnetograms, and dopplergrams. History of the 150-foot Tower.
  
  
• CHARA
  Center for High Angular Resolution Astronomy; Georgia State University. CHARA is constructing one of the world's largest optical interferometers at Mt. Wilson. It will be used for very high precision astrometry, measuring stellar diameters, star-spot activity, and searching for extrasolar planets.
  
  
• ISI
  The Infrared Spatial Interferometer is a U.C. Berkeley facility on Mt. Wilson. It is currently used for studies of circumstellar shells and late-type stellar evolution.
  
  
• UnISIS
  The University of Illinois Seeing Improvement System is a laser-guide-star adaptive optics system being built for the 100-inch telescope.
  
  
• CUREA
  The Consortium for Undergraduate Research and Education in Astronomy is a two-week summer course in astronomy held at Mt. Wilson Observatory each year. CUREA is now part of MWOA.
  
  
• Caltech
  The California Institute of Technology is one of the world's top technical schools. Caltech was created out of the older Throop Polytechnic Institute, primarily by George Ellery Hale. Caltech owns and operates Palomar Observatory as well as the Astronomy Department on campus. History of Caltech.
  
  
• The Carnegie Institution of Washington
  The money for the founding and original support of Mt. Wilson Observatory came from CIW, which still owns most of the Observatory facilities. CIW also operates the Carnegie Observatories, with their offices in Pasadena and their telescopes on Cerro Las Campanas in the foothills of the Andes Mountains in Chile.