Michelson chased the speed of light for fifty years because it was fun
Asked why he devoted his life to light, Albert Michelson reputedly answered that it was so much fun. He timed beams bouncing between California mountains 22 miles apart, fought forest-fire haze and perhaps an earthquake that nudged his baseline, and in 1907 became the first American to win a Nobel Prize in science.
Michelson was born on 19 December 1852 in Strelno, then in Prussia and now Strzelno in Poland, to a Polish-Jewish family that emigrated when he was two. His father kept a store in mining settlements, first Murphy's Camp in California and then Virginia City in Nevada, and that is where the boy was raised. President Ulysses Grant gave him a special appointment to the Naval Academy in 1869, and he later returned there to teach physics.
His first speed-of-light test began as a classroom demonstration in 1877. He refined the rotating-mirror technique of Léon Foucault, housing equipment in a frame shed on the Academy's sea wall, and in 1879 published a figure close to 299,910 kilometres per second. He was careful about hidden errors: checking his 100-foot steel tape against an official standard yard, he found it measured 100.006 feet and corrected for the gap. He also repeated readings many times, understanding that averages wobble less than single measurements.
In 1887, with Edward Morley in Cleveland, he looked for Earth's motion through the ether, the medium light supposedly travelled in, and found nothing. Repeating the test ever more precisely changed nothing. Hendrik Lorentz devised his contraction equations to explain the null result, and although Einstein later said he was not conscious of being directly influenced, the experiment became the classic demonstration that no ether can be detected.
From 1920 he planned a definitive measurement from Mount Wilson to Lookout Mountain, obtaining 299,796 kilometres per second, give or take 4. Seeking cleaner air, he then sent light back and forth inside a mile-long evacuated tube at the Irvine Ranch near Santa Ana. He died in Pasadena on 9 May 1931 with only 36 of 233 measurement series done; the result appeared after his death, in 1935. He also founded the physics departments at the Case School and the University of Chicago.
Source: Albert A. Michelson
