The Quest for Planet X: Exclusive Interview with Clyde Tombaugh, Discoverer of Pluto.

Conducted March 31, 1996

Interview by Paul Halpern

(Notes: This phone interview took place about seven weeks after Tombaugh celebrated his 90th birthday, as part of the research I conducted for my book, “The Quest for Alien Planets.” Tombaugh would pass away in January 1997.)

P.H. “When did you become interested in astronomy?”

C.T. “… about the 5th grade.”

P.H. “I understand that you had a background in farming originally.”

C.T. “Yes.”

P.H. “Was it surprising for your folks that you were interested in astronomy?”

C.T. “Not particularly, because I had an uncle who was interested in astronomy too.”

P.H. “Did you imagine when you were a boy that you would discover a planet?”

C.T. “No, that came as a surprise to me.”

P.H. “What was it like working at Lowell Observatory?”

C.T. “It was hard work and very exacting. It was cold. It was not altogether the most pleasant job to do and then the scanning of the plates was very tedious. The discovery of a planet doesn’t happen overnight. It’s impossible to find a planet that way. You have to take a photograph, and then a few nights later another photograph of the same region, and put the two together. The only clue you have is the motion, and that’s not easy.”

P.H. “How did you handle the tedium?”

C.T. “Well it was something interesting to do, and I wanted to do a good job of it, so I stayed with it but I made it.”

P.H. “I understand that you spent some time looking for a tenth planet.”

C.T. “They soon realized that Pluto was too small to produce the disturbances in Uranus. They thought perhaps that the real Planet X was yet to be found. But there isn’t a Planet X.”

P.H. “Have you seen the Hubble photos of Pluto?”

C.T. “Yes, very nice.”

P.H. “Did you ever expect to see such clear photos?”

C.T. “The best we could make out of Pluto was this tiny dot.”

P.H. “Do you think planets around other suns are common in the universe?”

C.T. “Could be … There’s trillions of stars. I’d be surprised if we were the only one.”

P.H. “Do you think if you weren’t retired you’d look for planets around other suns.”

C.T. “No, I don’t think I’d be doing that right now. You kind of get burned out after a while and you don’t want to do it anymore. I kind of got worn out.”

Originally published at

Paul Halpern is the author of Einstein’s Dice and Schrödinger’s Cat: How Two Great Minds Battled Quantum Randomness to Create a Unified Theory of Physics.

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