Mason Professor Uses Guinea Pig to Get Kids Interested in Pluto, Space Exploration

Harold Geller

Harold Geller

Pluto the guinea pig and Pluto the planet have more in common than you might think.

Harold Geller, of George Mason University’s observatory fame, likes guinea pigs. They’ll sit on your lap contently nibbling on a carrot while you watch TV.

He also likes introducing kids to the concept of space exploration. Just ask the families who wind around the observatory at Research Hall during “Evenings Under the Stars” events.

It was following a visit in February with students at Daniels Run Elementary School in Fairfax, Va., that Geller, director of the observatory and an associate professor, realized a book about NASA’s New Horizons mission to Pluto was needed.

After traveling three billion miles for nearly a decade, the New Horizons spacecraft is expected to reach Pluto on Tuesday, July 14. Geller combined forces with Michael Summers, a George Mason astronomy professor who’s a leading atmospheric scientist with New Horizons, to work on the book.

Geller has his own page and typically writes lengthy books pondering the existence of life on other planets, so he brought the same attention to detail to the info-packed “A Pluto Story,” which is aimed at middle grade readers.

product_thumbnailFirst, a little about Pluto the guinea pig: Geller adopted the tan and white Pluto from the Fairfax County Animal Shelter about three and a half years ago. Pluto was down on his luck—he had been found seriously injured in a park and spent three weeks at a veterinary clinic.

The cute little guy was easy to overlook, almost like his planetary namesake, but not to Geller, who has had guinea pigs in the past, notably Mars and Mercury.

“A Pluto Story” is filled with photos of the pig and the slightly more famous dwarf planet, offering comparisons between size and distance.

“If I only wrote a book about Pluto, it’s just boring facts,” Geller said. “There’s no hook for kids.”

In some ways, writing his first children’s book was easier than an adult book.

“You don’t have to write as much, but it’s harder because you have to think like a kid,” Geller said.

His goal is to inspire scientific wonder in elementary students, he said, because there’s plenty left to discover. The icy, dwarf planet may contain clues that will help researchers understand planets that exist well beyond the reach of Pluto.

Mason students use the university’s telescope, the largest on-campus telescope in the mid-Atlantic states, to study these exoplanets, so-called because they’re not orbiting our sun. About 1,930 exoplanets have been discovered thus far. Nearly a dozen are “Earth-like,” or of the same size and position to their sun as Earth is, Geller said.

As Geller and Summers conclude in their story: “We send spacecraft into space to explore, because we are explorers. Are you?”

You can find a copy of “A Pluto Story” here.

This article originally appeared on Mason News

Write to Michele McDonald at

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