Lowell Observatory

Lowell Observatory featuring an observatory and night scenes as well as a large group of people
This observatory is famous for discovering the dwarf planet Pluto and features many educational activities, historic telescopes and events for visitors.

Visit Lowell Observatory for daytime guided tours and nighttime telescope viewing sessions. Established in the late 19th century, the observatory is one of the oldest in the United States. The facility operates several telescopes, including the Pluto Discovery Telescope, for historical, educational and research purposes.

Start at the Steele Visitor Center on the Lowell Observatory campus. Here you’ll get acquainted with tour options and knowledgeable guides. Lowell’s present research telescopes are located outside Flagstaff however, the campus still operates as an administration and visitor hub. Venture outward from Steele Visitor Center to find historic telescope domes and other fascinating Lowell Observatory areas.

Take the Pluto Tour to see the Pluto Discovery Telescope. This device was built in the late 1920s for the specific purpose of sighting the hypothetical 9th planet in our solar system. In 1930, observatory assistant Clyde Tombaugh discovered an object in the telescope’s glass negatives. The object was later named Pluto and the discovery marks one of the most important moments in United States astronomical history.

Attend an evening viewing through the Clark Telescope, a 24-inch (61-centimeter) refracting telescope, built in the late 19th century. The telescope, listed as a National Historic Landmark structure, was used to study moons, double planets, comets and other celestial objects. In the 1980s, Clark Telescope’s purpose shifted from research to education, where it has since amazed more than 2 million guests.

Stop at the Rotunda Museum to see some of the observatory’s most precious artifacts, including measuring and calculating devices. The museum contains displays on the Pluto discovery and moon mapping for the Apollo program. Exhibits on the expanding universe discovery and the Lowell family history also feature at the museum.

Lowell Observatory, open daily, is located in Flagstaff, Arizona. Use a public parking area next to the Steele Visitor Center. The cost of admission covers both day and evening programs. Reservations are not essential however, it’s a good idea to check the official Lowell Observatory website for special events, tour times and seasonal programs.

Visit Lowell Observatory to look through state-of-the-art telescopes and learn about the facility’s monumental discoveries.

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