Persistence

Persistence paid off for American astronomer Clyde Tombaugh, who discovered the planet Pluto. After astronomers calculated a probable orbit for this "suspected" heavenly body, Tombaugh took up the search in March 1929. Time magazine recorded the investigation: "He examined scores of telescopic photographs each showing tens of thousands of star images in pairs under the dual microscope. It often took three days to scan a single pair. It was exhausting, eye-cracking work&md;in his own words, &ls;brutal, tediousness.' And it went on for months. Star by star, he examined 20 million images. Then on February 18, 1930, as he was blinking at a pair of photographs in the constellation Gemini, &ls;I suddenly came upon the image of Pluto!" It was the most dramatic astronomic discovery in nearly 100 years.