Home Opinion The man who discovered Pluto

The man who discovered Pluto


darrell heath

Darrell Heath

Astronomy Columnist

We never know where the next big discovery will come from or who will make it. Sometimes important discoveries come at us from left field and from unlikely sources. Take for example the discovery of Pluto, which will get its first ever visit from a spacecraft this month when NASA’s New Horizons will flyby the little world on July 14th.
Back in 1930 no one could have guessed that a self-taught 24-year old farm boy from Kansas would discover another world but Clyde Tombaugh was the exception rather than the rule.
Clyde Tombaugh, the oldest of six children, was born in 1906 to a farming family in Streator, Illinois. Like most such families of the time the Tombaugh’s were hard working and poor but they were also a close-knit and loving family and what they couldn’t afford to buy they either did without or made for themselves.
One luxury item the family did have access to was a 3-inch telescope owned by Clyde’s uncle who lived nearby. The uncle and Clyde’s father were avid stargazers and one night they invited the 12-year old boy to tag along with them on one of their nighttime excursions. The moment Clyde got a look at the Moon and its craters in that small telescope he instantly knew that he wanted to be an astronomer. His folks placed a high value on education and they encouraged their eldest son in his new passion. He checked out all the books he could find at his local library on astronomy and he read them from cover to cover. While Clyde loved his folks and his home life he knew that working a farm was not for him and he dreamed of one day entering college and earning a degree in astronomy. Once again his parents were fully supportive but fate was about to throw a wrench into Clyde’s plans. In 1927 the family had relocated to Burdett, Kansas and a hailstorm that same year demolished the Tombaugh’s crops; there would be no money available for his college tuition. Clyde was depressed but not discouraged. His family needed him and he decided to put plans of college on the backburner while he helped restore things with the farm.
Clyde continued his self-education in astronomy but he would need a telescope of his own. Telescopes were expensive and there was no way the Tombaugh’s could afford one. No money? No problem: Clyde built his own. In 1928, using the crankshaft of an old 1910 Buick and parts he scavenged off an old cream separator, Clyde built a fine 11 inch reflector telescope; he even ground his own mirror (which requires a great deal of precision!). With this newly built instrument Clyde began making detailed observations of the planets and sketching what he saw at the telescope. This was good training for an observational astronomer and the hard work was about to pay off by landing him a job that would eventually make his name known around the world.
At around the time that Clyde was born the astronomical community was a bit perplexed by the planet Neptune. Something seemed to be disturbing its orbit and causing it to be slightly off its predicted positions. Some scientists thought that there might be an unknown planet just beyond Neptune’s orbit that was exerting a gravitational tug to it, a mysterious Planet X. One man who took this idea seriously was wealthy Bostonian and amateur astronomer Percival Lowell. Lowell was already a well-known public figure from his popular books on Mars in which he claimed to have seen canals on the surface of the Red Planet while making observations from his private observatory in Flagstaff, Arizona. Lowell was a proponent of intelligent life on Mars and the public hung on his every word. His ideas (viewed skeptically by astronomers of the day) would even inspire H.G. Wells in the writing of his novel “War of the Worlds”.
Lowell began his search for Planet X in 1905 but, sadly, he died from a massive stroke in 1916 and the hunt would have to go on without him. Lowell left a large sum of money to keep operations going at his observatory but his widow contested the will and a court battle ensued that lasted until 1927. After the dust had settled the Lowell Observatory began looking for an astronomer to carry on the hunt for Planet X and Clyde Tombaugh applied for the job. He sent the director, Vesto Slipher, his observing logs and sketches and it was immediately apparent that Clyde was the right man for the job. Never having traveled very far from home Clyde set off for the American southwest to begin a whole new career.
Years later Clyde would recall: “After spending 28 hours in a chair car on the Santa Fe, I arrived at Flagstaff in the early afternoon of 15 January, 1929. Dr. Slipher met me at the depot and drove me up Mars Hill. The yellow pine forest was in stark contrast to the treeless plains of Western Kansas. I was rather unnerved by it all, everybody were strangers, 1,000 miles from home, and not enough money in my wallet for a return ticket home . . .”
Next week we will look at how Pluto was discovered and what we have learned about it over the intervening years.

Darrell Heath works at the University of Arkansas at Little Rock and is a producer and host for the UALR Television show “The Night Sky.”