Hale Telescope mirror.. It was completed in 1948 and is still in active use. The Hale Telescope represented the technological limit in building large optical telescopes for over 30 years. It was the largest telescope in the world until the Russian BTA-6 was built in 1976, and the second largest until the construction of the Keck Observatory Keck 1 in 1993. Hale supervised the building of the telescopes at the Mount Wilson Observatory with grants from the Carnegie Institution of Washington: the telescope in 1908 and the telescope in 1917. These telescopes were very successful, leading to the rapid advance in understanding
Bok Telescope telescope since 1991, uses a NICMOS array which was built during the development of the NICMOS instrument on the HST. Bok Telescope The Bok Telescope (also known as the 90-inch) is the largest telescope operated solely by Steward Observatory. It finds much use from astronomers from University of Arizona, Arizona State University, and Northern Arizona University, with instruments capable of both imaging and spectroscopy. The telescope operates year-round, except during the August summer-shutdown when maintenance is performed while the weather is poor (Arizona's monsoon season lasts from roughly July through August). The Bok Telescope was named after the prolific astronomer