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I Heart Pluto Festival To Commemorate 90th Anniversary of Pluto Discovery

Published: Friday, February 14, 2020 - 4:04pm
Updated: Friday, February 14, 2020 - 4:10pm
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Lowell Observatory Archives.
Clyde Tombaugh at a machine called a Zeiss Blink Comparator, used in the discovery of Pluto. Two glass plates of the same area of the sky were blinked back and forth to look for the movement of objects against the background stars.

Lowell Observatory will celebrate the 90th anniversary of Pluto's discovery with events on Feb. 15 and 18.

Nine decades ago, Clyde Tombaugh used a special device called a blink comparator to discover Pluto by rapidly comparing images of the sky taken at different times.

A rededication of that instrument will accompany several talks, a book signing and a space art exhibit.

Special guests will include a spate of guests related to Pluto discoveries: Alden Tombaugh (son of Pluto discoverer Clyde Tombaugh), Jim Christy (discoverer of Pluto's largest moon, Charon), Charlene Christy (Jim's wife and the namesake of Charon), Larry Wasserman (Lowell Observatory astronomer and co-discoverer of Pluto's atmosphere), Will Grundy (Lowell Observatory planetary scientist and leader of the New Horizons surface composition team) and Lowell Observatory historian Kevin Schindler.

Also on offer: a Pluto-themed song by the Flagstaff Community Band, a commemorative Pluto Porter by a local brewery and a chance to sample the Pluto Roll at a sushi shop visited by Tombaugh when it was still the Black Cat Cafe.

Events at the observatory kick off at 10:30 a.m. Saturday and are covered by the standard entry fee.

More information is available at