The 100-inch Hooker telescope saw first light on Mount Wilson above Pasadena, Calif., 104 years ago Tuesday. The Mount Wilson Observatory telescope remained the largest in the world from 1917 until 1949.
Edwin Hubble sat at its eyepiece, staring at the crosshairs, tracking stars by making manual adjustments. In the 1920s, Hubble placed glass plates at the focus of the telescope. These photographic plates led to an astounding discovery: the Andromeda Galaxy was separate from the Milky Way. This changed our idea of the scale of the universe. There were billions of galaxies, all expanding away from each other.
Plans for the telescope began only months after the 1906 San Francisco earthquake. John Hooker, of Los Angeles, gifted the funds for the 4½-ton glass disk that was shaped into the telescope’s 6,000-pound mirror — the biggest solid glass mirror ever made. It was hauled up the challenging 9-mile narrow mountain road by a special truck assisted by mules, yet no one knew if it would work. In the early hours of Nov. 2, English poet Alfred Noyes chronicled the first viewed object: a clear image of Jupiter.
Albert Einstein visited Mount Wilson during his three winters at California Institute of Technology.
The historic observatory recently survived the powerful Bobcat Wildfire. Firefighters pushed back the raging blaze within feet of the telescope domes.
First Published: November 2, 2021, 10:00 a.m.
