Mount Wilson Institute
740 Holladay Road
Pasadena, CA 91106 

Notable for: unique telescope mirror support and use of mercury flotation to reduce friction

Owner, if different than above: Mount Wilson Observatory (Hale)

Plaque location, if specific: inside observation booth of the Hooker Telescope

Links:
Request time on the 100-inch! Owner site: http://www.mtwilson.edu/
Current view from top of 150-foot solar tower telescope: http://www.astro.ucla.edu/%7Eobs/towercam.htm
Mount Wilson Observatory Virtual Tour: http://www.mtwilson.edu/vir/100/

More about . . .
The increased light-grasp of this telescope made possible many notable advances in structural cosmology between 1924 and 1930, which have revised our ideas about the universe. One of these advances was that spiral nebulae are galactic units like our own; another was the idea of an expanding universe. George Ellery Hale began planning this project in 1906; Francis G. Pease was the chief designer and mechanical engineer. The telescope's mirror support and the use of mercury flotation to reduce the friction are among its outstanding mechanical engineering features.

Visiting Info: The observatory is open to visitors every day from 10 AM to 4 PM from April 1 through November 30, weather permitting. Special group tours may still be requested. Contact: Gale Grant.

Ceremony Notes: June 1981

Image:
Credit:  J. Lawrence Lee, ASME copyright 1998
Caption:  Drawing of Mt. Wilson Observatory's 100-inch telescope, which has been designated an ASME historic mechanical engineering landmark.