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Felicia Fonseca, Associated Press
This March 13, 2015, photo, shows the entrance to the exhibit, Pluto at 85: From Discovery to New Horizons at Lowell Observatory in Flagstaff, Ariz. A yearlong exhibit at the observatory celebrates the work of the amateur astronomer in the city who discovered the now-dwarf planet in 1930.

FLAGSTAFF, Ariz. — A sushi restaurant in downtown Flagstaff added a Pluto roll to its menu. A yearlong exhibit celebrates the work of the amateur astronomer in the city who discovered the now-dwarf planet in 1930. And a walking tour leads people to the movie theater and restaurant the astronomer visited the night of his big find.

Pluto has taken on new prominence in Flagstaff, where it was spotted by Clyde Tombaugh from Lowell Observatory and where residents have since been fascinated with the icy world. The worldwide attention that followed the discovery meant Flagstaff would be known as more than a railroad, cattle ranching and timber community on the way to the Grand Canyon.

The "Year of Pluto" exhibit at the observatory comes as NASA's New Horizon's spacecraft completes a nine-year journey to the unexplored world in July. New images will be beamed to Earth that will be shown and studied at the observatory that overlooks downtown Flagstaff.

"The whole city of Flagstaff has a scientific bent," said local artist Paula Rice, who plans to make a figurative ceramic piece of Pluto based on the new images. "And we live at 7,000 feet in altitude, so our ocean is the night sky. We naturally look up."

Tombaugh's fascination with astronomy landed him at Lowell Observatory in the 1920s, shoveling snow from a telescope dome and feeding coal into stoves. The job had the added benefit of photographing the night sky in search of a mysterious Planet X that the observatory's founder, Percival Lowell, had plotted before he died in 1916.

The task was "mind-numbingly boring" as Lowell historian Kevin Schindler describes it. Tombaugh would analyze 14-inch-by 17-inch photos of the sky crowded with about 300,000 stars, switching between two images taken several days apart to detect any movement.

On Feb. 18, 1930, the then-24-year-old Tombaugh spotted a small shift in the position of an object in the plates. That shift showed what would become known as Pluto.

Since then, discoveries linked to Flagstaff and Lowell astronomers include Pluto's atmosphere and three of the five moons found so far around Pluto.

Some 80,000 people each year visit Lowell Observatory, where a new exhibit showcases Tombaugh's log books, letters, Lowell's original calculations, one of the original discovery plates and a telegram sent on behalf of a young English girl who suggested the name Pluto in honor of the Roman god of the underworld. The symbol for Pluto, PL, also is a tribute to Lowell.

Tombaugh died in 1997. While his discovery of Pluto cast Flagstaff into the spotlight, so did its reclassification to dwarf planet in 2006.

The question isn't well settled among the observatory staff or Flagstaff residents who "feel very defensive about Pluto and want to protect it," curator Samantha Thompson said. The exhibit that opened in March begins by asking "Is Pluto a planet?" and leaves the answer up to visitors.

Said Flagstaff Mayor Jerry Nabours: "I think we got more publicity having Pluto's status demoted than we got from the discovery of Pluto."