Celebrate the anniversary of Pluto’s discovery Feb 15 & 18, 2020 with an event 90 years in the making!

Come show your love for our frosty ninth planet in cold and snowy Flagstaff, Arizona, where Pluto was discovered by Clyde Tombaugh 90 years ago, on February 18, 1930.

Festival Events Include:

• A talk by keynote Dr. Alan Stern, Principal Investigator of the New Horizons mission.

• See the A. Lawrence Lowell Astrograph, which was used to photograph the images of Pluto.

• See the blink comparator that was used to discover Pluto, back home from loan to the Smithsonian Institution.


For more events, and festival information please visit:


  • Occurred Saturday, February 15th, 2020 — all day
  • Occurred Tuesday, February 18th, 2020 — all day


Lowell Observatory

1400 W Mars Hill Rd
Flagstaff, AZ 86001


Heather Craig

At Lowell Observatory, History and Science come together! Guided tours of the historic campus give visitors a chance to explore the famous Clyde Tombaugh to the famous path Clyde Tombaugh took the night he discovered Pluto.

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