On Jan. 26, 1949, the monumental Hale Telescope saw its first light. With a staggering 200-inch diameter mirror, Hale became the largest telescope in the world for a 30-year run.
Work on Hale started in 1936, putting the basic structure of the telescope together. For the mirror, however, the team wanted a material that wouldn’t expand or contract with temperature changes. Designers initially went with quartz, but that idea was eventually abandoned.
Instead, the Hale team looked to none other than the Corning Museum of Glass to cast the massive mirror. When it was finished, the mirror was shipped from Corning to Pasadena by train. Infatuated by the telescope, the public often traveled to the tracks to watch the mirror go by.
After a construction period of more than a decade, the first official picture using the monstrous scope was taken by Edwin Hubble on the night of the Jan. 26, 1949. The photograph was of NGC 2261, or Hubble’s Variable Nebula. Managed by Caltech, the telescope still contributes to research in fields such as solar system studies, stellar population, exoplanets, and more.
Soon after its completion, Walter Baade pointed Hale at the Andromeda galaxy in search of stars that could be used to measure distance. To his surprise, his calculations showed that the galaxy was twice as far as previously thought. Baade’s calculations completely changed astronomers’ perception of space, essentially doubling the size of the known universe. Additionally, Allan Sandage used Hale to determine the rate of the universe’s expansion. His final result was remarkably close to the now accepted rate measured by the Hubble Space Telescope 50 years later.
This information was gathered from sites.astro.caltech.edu.
