MWO founder George Ellery Hale atop Mt. Wilson, 1904 Huntington Library


60-inch Observing

100-inch Observing

Filming at MWO

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Scientific Research Programs

Mount Wilson is host to several ongoing research projects that use the on-site facilities operated by the Mount Wilson Institute and other organizations. Scientific research has been conducted at the Observatory since 1904, and new cutting-edge facilities are keeping Mount Wilson in the forefront of astronomical research as the observatory pursues its second century of operation.

100-inch telescope The Mount Wilson Institute operates two nighttime telescopes. The Hooker 100-inch telescope - the world's largest from 1917 to 1948 - is available for use by qualified scientists and is an ideal testbed for the development of new instrumentation and techniques and carrying out synoptic observational programs. Inquiries regarding its availability and other aspects of its scientific useage should be addressed to the Observatory director.

60-inch telescope The 60-inch telescope, completed in 1908 and the world's largest until the 100-inch telescope was completed nine years later, is now largely devoted to public viewing. Fee and scheduling information is available here.

Established by the Carnegie Institution of Washington in 1904 to study our own star - the Sun - the observatory is still home to three solar telescopes. The 150-foot tower telescope completed in 1912 and now operated by the Division of Astronomy and Astrophysics of the University of California, Los Angeles (UCLA) is used to investigate long-term changes in solar magnetic activity and short-term oscillations in the Sun to aid in understanding its internalprocesses.
The 60-foot tower telescope completed in 1908 and currently operated by the Department of Physics and Astronomy of the University of Southern California (USC) is part of a worldwide network of instruments used to monitor movement within the Sun's surface, a field of study known as helioseismology. The Snow solar telescope was brought to Mount Wilson from Yerkes Observatory in 1904 and was the first permanent telescope designed for solar studies and dedicated to that purpose anywhere in the world. It is now used primarily for educational purposes, especially by the annual CUREA program.Solar telescopes

With steadier air above it than any North American location, Mount Wilson is an ideal location for a field of study known as "interferometry." In an interferometer, the light from an astronomical object is collected by two or more telescopes and then recombined at a central location. After having followed slightly different paths through each of the telescopes, the light from the object of study interacts with itself after recombining. By studying theses interactions, astronomers can detect much finer detail than would be possible with a single telescope. One of the first interferometers used for astronomical research was built by Albert Michelson and Francis Pease for use on the Hooker 100-inch telescope in 1920. Consisting of a beam placed on the end of the telescope, it used movable mirrors that directed the light from an object into the telescope along slightly different paths.
ISI telescope

Since then, several interferometers have taken advantage of the excellent conditions at Mount Wilson. The Infrared Spatial Interferometer (ISI), operated by the the University of California at Berkeley, uses three 65-inch telescopes to collect infrared radiation from celestial objects. While it is suited to several types of investigation, ISI has concentrated primarily on measuring the diameters of old giant and supergiant stars and study dust shells that form around these stars which change over time scales of years.

The Center for High Angular Resolution Astronomy (CHARA) of Georgia State University has built the highest resolution interferometric telescope array in the world for the study of objects in visible and infrared wavelengths. With six 40-inch telescopes at distances of up to 330-meters apart (almost 1/4 mile), the CHARA Array can detect much finer detail on distant objects than ever before. Fully operational since 2005, the CHARA array is being used to measure sizes, shapes, temperatures, distances, masses and luminosities of star. In 2007, it produced the first image ever made of the surface of a sun-like star. More recently, CHARA successfully imaged the once-every-27-years eclipse of the previously mysterious binary star system epsilon Aurigae as well as the famous eclipsing binary star Algol (beta Persei). CHARA