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A cathedral to the cosmos: Even after its demotion, Pluto is still a star at Flagstaff’s Lowell Observatory

Discovered by Clyde Tombaugh in 1930, the dwarf planet’s popularity hasn’t waned with visitors to the 128-year-old Arizona observatory

Giovale Open Deck Observatory. | Photo courtesy of Lowell Observatory

Pluto, a heavenly body so small that it can’t clear celestial garbage out of its path, was reclassified as a dwarf planet in 2006. But not everyone who visits Lowell Observatory in Flagstaff, Arizona, agrees with the demotion. Lowell’s historian, Kevin Schindler, says the observatory’s “vote with your wallet” ballot boxes prove that even 15 years later, Pluto’s status is still polarizing. Boxes marked “planet” and “I don’t care! I just want to support Lowell Observatory” are usually significantly more full of dollars and Euros than the other two, labeled “dwarf planet” and “other.”  

In 1894, Percival Lowell founded the observatory in the dark and sparsely populated Arizona Territory. Lowell, who was searching for extraterrestrial life or a new celestial body he called Planet X, purchased a Clark Telescope for $20,000 (nearly $600,000 today), the best telescope money could buy.

But it was another planet that caught his attention: Lowell was convinced that intelligent life inhabited Mars. He spent years viewing the red planet, mapping its surface, and looking for builders of the canals he saw. The New York Times provided sensational coverage of Lowell’s findings: An article titled “Martians Build Two Immense Canals in Two Years” was published in August 1911.

ballot boxes at the lowell observatory where tourists vote with their dollars to answer the question "what should pluto be called"
Ballot boxes. | Photo: Sarah Gilbert
a very large telescope is pointed at the night sky under the dome of an obersvatory
The Clark telescope. | Photo courtesy Lowell Observatory

On Saturday nights, Lowell would invite townspeople to look through his Clark Telescope for extraterrestrials. At Lowell’s soirees, science and pop culture mingled. Schindler says, “Using the Clark Telescope, Lowell inspired scientists to prove or disprove his provocative theories about life on Mars, the general public to think beyond their own planet, and science fiction writers, such as H.G. Wells, which incorporated certain Lowellian ideas into their work.”

Perched atop Mars Hill, the private observatory is now an institution in Flagstaff, designated the first International Dark Sky City in 2001. 

Planet X

Lowell was sure that our solar system had a distant ninth planet that he called Planet X. But before he could find it, he died in 1916 and was buried in a mausoleum (with a glass-ceiling) steps away from the Clark Dome. Thirteen years later, self-taught astronomer Clyde Tombaugh began photographing the heavens with an astroscope (a telescopic camera). For hours on end, he compared photographs taken days apart, looking for a point of light that moved. The images on display at Lowell Observatory make even the most complex games of connect-the-dots look like child’s play.

Comparing photographs on February 18, 1930, Tombaugh found a point of light that moved over time. “I have found your Planet X,” he told his supervisor. Pluto would soon join Uranus and Neptune as the third and final planet in our solar system discovered by a telescope—Mercury, Venus, Mars, Jupiter, and Saturn are all visible with the naked eye.

The observatory’s Pluto Discovery Dome houses Tombaugh’s astroscope; the story of his discovery and how Pluto got its name are illustrated on the surrounding walls. Venetia Burney, an 11-year-old English schoolgirl, suggested the name Pluto, the Roman god of the underworld. 

A black and white photo of a man wearing glasses and a suit looking through a telescope
Clyde Tombaugh’s photo in the Pluto Discovery Dome. | Photo: Teresa Otto
a large domed observatory lit by red lights under a night sky full of stars
The Clark telescope outside. | Photo courtesy of Lowell Observatory

Tombaugh spent years examining and photographing Pluto with the higher-powered Clark Telescope. Recently refurbished, the telescope is enshrined under a ponderosa pinewood dome, lit with a red light to preserve night vision. Tombaugh died in 1997, and when the New Horizons spacecraft traveled 9 years and 3 billion miles to snap “closeups” of Pluto in 2006, some of his ashes went along for the ride. Every February, the observatory honors Tombaugh and celebrates the anniversary of Pluto’s discovery at its I Heart Pluto Festival. 

One giant leap

In the 1960s, after John F. Kennedy proclaimed we’d have a man on the moon before the end of the decade, artists used the Clark Telescope to map the moon’s features. Neil Armstrong took a good look at the lunar surface before his small step for man and giant leap for mankind.

Over Lowell Observatory’s 128-year history, its astronomers not only discovered Pluto and studied Mars, but they found galaxies and proved the universe is expanding. Lowell believed astronomers should have the freedom to explore anything in the universe that interested them—and that the observatory’s discoveries should be shared with the public. To that end, Lowell Observatory remains a private observatory that’s open to the public.

As I peer through the telescope’s eyepiece, I realize that I’m not only following in the footsteps of Lowell, Tombaugh, and the Apollo astronauts, but also Bill Nye the Science Guy, dinosaur hunter Jack Horner, Hillary Clinton, and Queen’s Brian May, who earned a PhD in astrophysics.

“Taking a group into the dome, it’s like they’re going into the Lincoln Memorial,” Schindler says. “So often people start whispering. It’s a reverential experience—an amazing building, a telescope that really does shine. And it really does feel like you’re in the presence of something remarkable, which you are.”

Observatory visitor Jim Davies says the Clark Dome is a “cathedral to the cosmos.” 

a large wooden domed observatory houses a large telescope
Kevin Schindler and the Clark telescope. | Photo: Teresa Otto

Lowell’s legacy continues

A 350-foot walkway leads to the Pluto Discovery Dome: Built so 1 foot equals 10 million miles in space, the walk begins at the sun and passes a marker for each planet. Educators at the observatory share the wonders of the cosmos through historical exhibits, education, and real-time experiences; talks and tours are offered throughout the day. 

By night, visitors are shown around the galaxy with laser pointers aimed at constellations. “Of all the things I’ve been fortunate enough to do at the observatory, there’s nothing like standing at the Clark Telescope and seeing somebody look through the eyepiece for the first time,” Schindler says. “For that moment, it’s just them and the telescope. And they’re making that discovery for themselves just like Percival Lowell did.”

And before you leave, don’t forget to cast your vote.

If you go 

Visit Lowell Observatory’s website for up-to-date hours, admission fees, and tour information.