200-inch Telescope

  • Prosperity
  • 1928

The pioneering U.S.-based telescopes used by scientists to make fundamental scientific discoveries have been products of private philanthropy. The first modern mega-telescope was the 60-inch reflector, at that point the world’s biggest, built on Mount Wilson in California with a 1904 grant from the Carnegie Institution. This historic instrument allowed measurement of the size of our galaxy, and plotting of the position of our solar system within it. Carnegie also funded the 100-inch telescope that went into use on Mount Wilson a decade later. Edwin Hubble used it to show that there are many galaxies, and that the universe is continuing to expand.

In 1928, $6 million of Rockefeller funding (at that point the largest single grant they had ever awarded) paid for construction of the 200-inch Hale telescope on Mount Palomar. After years of work, the original mirror proved impossible to manufacture. Corning Glass of upstate New York was called in to create an enormous blank using their new Pyrex product, which was eventually transported across the country, polished, and finally opened to the heavens two decades after the initial Rockefeller gift. The Hale telescope was the world’s largest for 45 years (1948-1993), and is still a workhorse of modern astronomy, used nightly for a wide range of studies.