http://www.klx.com/clyde/nmsu.html
Born on Feb. 4, 1906, on a farm near Streator, Ill., Tombaugh moved with his family to a farm near Burdett, Kansas, during his high school years. He shared his father's keen amateur interest in astronomy, and when he wanted a telescope more powerful than his 2 1/4-inch Sears Roebuck model, he began grinding mirrors and making his own.
Using a hand-made 9-inch telescope, he made meticulous sketches of Jupiter and Mars and sent some of them to the Lowell Observatory. He thought he might get some advice from the professionals. Instead he was offered a job. It happened that the observatory was looking for a good amateur astronomer who could operate a new photographic telescope.
Tombaugh was hired in 1929 as a junior astronomer to join in the search for a "Planet X" beyond Neptune, a search begun in 1905 by Percival Lowell. Working through the nights in a cold, unheated dome, he made pairs of exposures of portions of the sky with time intervals of two to six days. These were scrutinized under a device called a Blink-Comparator in hopes of detecting a small shift in position of one of the hundreds of thousands of points of light -- the sign of a planet among a field of stars.
On the nights of Jan. 23 and 29, 1930, Tombaugh made two such photographs of the region of the star Delta Geminorum. On the afternoon of Feb. 18, comparing the plates with the Blink-Comparator, he detected the telltale shift of a faint, starlike image. The discovery was confirmed with subsequent observations and announced to the world on March 13, 1930.
FYI - I grew up in a central IL town located about 15-20 miles away from Streator. Clyde should consider himself lucky to move out of there. It was known as a hideaway for roughnecks who probably wouldn't have appreciated his diligent studies.
