The distant planet (or dwarf planet) of Pluto will forever be tied to Flagstaff's Lowell Observatory, the place where Clyde Tombaugh discovered Pluto in 1930. And that connection endures: Lowell's scientists played key roles in the recent New Horizons mission, which sent a space probe hurtling past Pluto.

That relationship is the focus of Pluto and Lowell Observatory: A History of Discovery at Flagstaff, a new book by Kevin Schindler, a longtime Lowell employee who's now the observatory's historian, and Will Grundy, a Lowell planetary scientist who heads one of the New Horizons teams.

"We have a lot of visitors who come up here and are excited about learning about Lowell, and particularly Pluto," Schindler says. "When they leave, they're always asking, 'Is there something I can read to learn more?'"

That was part of the reason for writing the book, but Grundy says New Horizons added a new chapter to Pluto's story — one that wasn't included in earlier books about the planet.

That mission is the focus of the second half of the new book, but Grundy notes that even before New Horizons, Pluto's story was tied to Arizona. In the 1950s, for example, a Lowell telescope was used to determine Pluto's rotation period. Later, another telescope in the area helped discover Pluto's moon Charon, and methane on the planet's surface was detected at Kitt Peak National Observatory near Tucson. "It's almost sort of like our little planet," Grundy says.

Schindler says the book is a culmination of his more than 20 years at Lowell, during which he learned about Tombaugh's history and the circumstances of Pluto's discovery. He did additional research at New Mexico State University, where Tombaugh's post-Lowell correspondence is kept. "There really was a lot of neat stuff, especially the personal stuff — letters between him and his parents, and how they found out about the discovery," he says.

The book includes contributions from Tombaugh's daughter and son; from Lowell trustee W. Lowell Putnam, the great-grandnephew of observatory founder Percival Lowell; and from S. Alan Stern, principal investigator on the New Horizons mission. Additionally, Lowell Director Jeffrey Hall and astronomer Gerald van Belle wrote an epilogue on the well-known debate over whether Pluto is a planet or a dwarf planet.

That debate "resonates with people in a way that doesn't have anything to do with science," Grundy says. "They stick up for the underdog."

Schindler adds: "The closer people live to Flagstaff, the more outspoken they are that Pluto is a planet."

Kevin Schindler and Will Grundy's book Pluto and Lowell Observatory: A History of Discovery at Flagstaff is available at Lowell Observatory and on Amazon. Proceeds from sales of the book support the observatory's educational and scientific endeavors.

— Noah Austin, Associate Editor