Lowell Observatory

Not to be confused with Lovell Telescope.

Lowell Observatory

The Clark Telescope Dome on Mars Hill
Alternative names	Flagstaff Observatory
Organization	Private institution
Observatory code	690
Location	Flagstaff, Arizona
Coordinates	35°12′10″N 111°39′52″W
Altitude	2,210 m (7,250 ft)
Established	1894
Website	lowell.edu
Telescopes
Lowell Discovery Telescope 4.28 m (169 in) telescope (located at Happy Jack, Arizona) Perkins Telescope 180 cm (72 in) cassegrain telescope (located at Anderson Mesa) John S. Hall Telescope 110 cm (42 in) Ritchey-Chretien telescope (located at Anderson Mesa) Unnamed telescope 79 cm (31 in) reflecting telescope (located at Anderson Mesa) LONEOS Schmidt Telescope 64 cm (25 in) catadioptric (located at Anderson Mesa) 24-inch Clark Telescope 61 cm (24 in) Alvan Clark refractor Unnamed telescope 53 cm (21 in) reflecting telescope Unnamed telescope 46 cm (18 in) astrograph Dyer Telescope 61 cm (24 in) PlaneWave CDK telescope Abbot L. Lowell Astrograph (Pluto Discovery Telescope) 33 cm (13 in) astrograph Planet Search Survey Telescope (located at Anderson Mesa) Navy Precision Optical Interferometer six-aperture astronomical interferometer with baselines up to 437 m (1,434 ft) (located at Anderson Mesa, operated in partnership with the USNO (through NOFS) and the NRL) Lowell Observatory U.S. National Register of Historic Places U.S. National Historic Landmark The Slipher Rotunda Museum at Lowell Observatory Location within Arizona Location within the United States Built 1894 MPS Flagstaff MRA (AD) NRHP reference No. 66000172 Significant dates Added to NRHP October 15, 1966 Designated NHL December 21, 1965
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Lowell Observatory is an astronomical observatory in Flagstaff, Arizona, United States. Lowell Observatory was established in 1894, placing it among the oldest observatories in the United States, and was designated a National Historic Landmark in 1965. In 2011, the Observatory was named one of "The World's 100 Most Important Places" by Time magazine. It was at the Lowell Observatory that the dwarf planet Pluto was discovered in 1930 by Clyde Tombaugh. Lowell is home to a 24-inch Clark Refracting Telescope, built in 1896, which is still in use today for public observing. Lowell sees over 150,000 annual visitors and is active in exoplanet and minor planet research.

The observatory was founded by astronomer Percival Lowell of Boston's Lowell family and is overseen by a sole trustee, a position historically handed down through the family. The first trustee was Lowell's third cousin Guy Lowell (1916–1927). Percival's nephew Roger Putnam served from 1927 to 1967, followed by Roger's son Michael (1967–1987), Michael's brother William Lowell Putnam III (1987–2013), and current trustee W. Lowell Putnam. The trustee appoints an Executive Director to oversee operations of the observatory, and consults with an advisory board. The current Director is Dr. Amanda Bosh.

Multiple astronauts attended the Lowell Observatory in 1963 while the Moon was being mapped for the Apollo Program, and many observed through the Clark Telescope.