The Pluto Files

TV Program Description
Premiere Broadcast on PBS: March 2, 2010

Dear Mr. Tyson, I think Pluto is a planet. Why do you think Pluto is no longer a planet? I do not like your anser!!! Pluto is my faveret planet!!! You are going to have to take all of the books away and change them. Pluto IS a planet!!!!! Your friend, Emerson York

When the American Museum of Natural History's Hayden Planetarium stopped calling Pluto a planet, director Neil deGrasse Tyson found himself at the center of a firestorm led by angry, Pluto-loving elementary school students who wrote letters like the one above. But what is it about this cold, distant, icy rock that captures so many hearts? Now, almost 10 years after the news broke on the front page of The New York Times, "Pluto Not a Planet? Only in New York," and nearly four years after the IAU (International Astronomical Union) officially reclassified the ninth planet as a plutoid, NOVA travels cross-country with Tyson to find out. Based on Tyson's book of the same name, "The Pluto Files" premieres Tuesday, March 2, 2010, at 8pm ET/PT on PBS.

From Boston to California, Tyson's spirited journey explores the history of Pluto—from the time of its discovery to its fall from planethood. Along the way, Tyson meets a fascinating cast of characters, from scientists who argue over Pluto's status to die-hard "Plutophiles"—regardless of where they stand they have one thing in common: strong opinions about Pluto. "The Pluto Files" also includes special appearances by Stephen Colbert, Jon Stewart, Diane Sawyer, and Brian Williams, who share their affection for the former planet. "I'm sorry, I thought planets might be one of the constants in life," Colbert jests. "But scientists just love change more than anything else. I'm sorry that's not change I can believe in."

At Harvard University's football field, Tyson meets up with some heavy hitters at the top of their scientific game. In a good-natured debate over Pluto's status, Tyson keeps "score" of Pluto's planet-like characteristics vs. its oddball traits with the help of planetary scientist Mark Sykes, astrophysicist Brian Marsden, and Harvard science historian Owen Gingerich. Pluto's miniscule size and oblong orbit are some of the reasons Marsden says Pluto is not a planet, while Sykes says Pluto is a planet because it's round, like all the other planets, not potato-shaped like most asteroids.

"Like any good road trip, 'The Pluto Files' is filled with great stories; this one includes scientific history, current debate, and human emotion," remarks Paula S. Apsell, senior executive producer for NOVA and director of the WGBH Science Unit. "Pluto sparked something in the American people, and this program is a wonderful tribute that viewers of all ages will find entertaining and enlightening."

At Walt Disney World in Orlando, Florida, Tyson meets world-famous cartoon character Pluto, and Walt Disney's great-nephew, Roy Patrick Disney. While there's no written documentation to prove the good-natured bloodhound was named after the planet (one of the most frequently asked questions at the Disney archive), it is well known that Walt was fascinated with space exploration. Roy Patrick believes it "wasn't an accident, it was fate." But however the loveable pup got its name, Tyson thinks it's had a profound effect on planet Pluto, giving it a "warm and fuzzy feeling," says Tyson. "Cosmic objects don't normally trigger warm and fuzzy feelings."

One of the most memorable stops along the way is Streator, Illinois, home to Pluto discoverer Clyde Tombaugh. In 1930, Tombaugh, a self-taught 24-year-old farm boy with a passion for studying the universe, reported his discovery, one that remains the talk of the town. Tyson gets a strong sense of Tombaugh's "hero" status from chatting with folks at the local barber and coffee shops. They take great pride in Tombaugh's world-renowned discovery—honoring him with plaques and naming their main street after him.

Delving deeper into Tombaugh history, Tyson visits with Tombaugh family members in New Mexico, including his 97-year-old widow. He's humbled by the collection of Tombaugh's homemade telescopes, made from discarded car parts and not always surplus farm equipment. In a local church, while looking at a stained glass window that celebrates Tombaugh's life and remarkable achievements, Tyson thoughtfully reflects, "How many scientists have stained glass windows of them? It's more than just a celebration of his discovery; it's a celebration of his life, overcoming obstacles that would keep most people down. To me, that's the message here."

In California, Tyson sits down for a barbecue and celestial conversation with astrophysicists Mike Brown and David Jewitt. It was their desire to see beyond the outer solar system that led to the discovery of the Kuiper Belt and eventually the debate over Pluto's planetary status. Discovered by Jewitt and his colleague Jane Luu in 1992, the Kuiper Belt is a region of the solar system never before seen. Billions of miles wide, it's chock full of celestial objects, leftovers from the formation of the solar system 4.5 billion years ago. Most of these leftovers are much smaller than Pluto. But in 2005, Brown found something extraordinary: a Kuiper Belt object larger than Pluto. Was it the 10th planet? Was Pluto still a planet? The scientific community was faced with a problem—a Pluto problem.

The IAU, in charge of naming celestial objects, couldn't give Brown's discovery an official name until they decided what it was: a planet or an iceball in the solar system's deep freeze. That meant the IAU had to do something that hadn't been done since the ancient Greeks formally defined the word planet. The new definition of planet states that a planet must clear the neighborhood around its orbit—not good news for Pluto or Brown's discovery since they're both surrounded by Kuiper Belt objects.

So in 2006, after 75 years in the limelight, Pluto was no longer a planet. Many planetary scientists were upset with the news. Within days of the announcement, a petition signed by hundreds of scientists rejected the IAU decision. On his way back to New York, Tyson stops at John Hopkins University's Applied Physics Lab in Baltimore, Maryland, where he meets Alan Stern, a staunch Pluto supporter and one of the world's leading experts on Pluto. Stern is the principal investigator of the New Horizons mission—a nine-and-a-half-year voyage to Pluto, which launched in 2006. Stern's assessment of Pluto is that it is a new kind of planet, a dwarf planet. "It looked like the solar system consisted of four terrestrial planets, four giant planets, and misfit Pluto," says Stern. "But today, instead, we see a solar system with four terrestrial planets, four freakishly giant planets, and a whole cohort of Pluto-like objects that turn out to be the dominant class of planet in our solar system."

So then, what is Pluto? Is it a planet? Is it just an ice ball? The debate continues.

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Neil deGrasse Tyson and Pluto dog

Neil deGrasse Tyson gives Pluto an astronomy lesson. Gene Duncan ©Walt Disney World

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astronomers play on Harvard field

At Harvard's stadium, astronomers and science historians play around with an eight-foot-diameter model of the sun. By comparison, Pluto is the size of a ball bearing from a roller skate. ©WGBH Educational Foundation

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Alan Stern and Neil deGrasse Tyson

Alan Stern, who defends Pluto's status as a planet, greets Neil outside of Johns Hopkins University's Applied Physics Lab. ©WGBH Educational Foundation

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Neil deGrasse Tyson and Annette Tombaugh-Sitze

Clyde Tombaugh's daughter Annette visits Neil to see his headline-making Pluto exhibit at the Hayden Planetarium in New York City. ©WGBH Educational Foundation

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