The 200-inch Hale Telescope

The 200-inch (5.1 m) Hale Telescope (f/3.3) was the world's largest effective telescope for 45 years (1948 - 1993).  It is still a workhorse of modern astronomy.  It is used nightly for a wide range of astronomical studies.  On average the weather allows for at least some data collection about 290 nights a year.

Images of the Hale Telescope and Laser guide star images.

Russell Porter's 1938 Cutaway drawing of the Hale Telescope (~500kb)

Watch members of the Palomar day crew install the adaptive optics instrument PHARO (Palomar High Angular Resolution Observer) into the Hale Telescope's Cassegrain cage in this time-lapse movie (~62 mb Quicktime movie).

Watch another instrument change as the Large Format Camera is pulled out of prime focus (at the top of the Hale Telescope) and the Wide-field Infrared Camera is installed in its place this time-lapse movie (~31 mb Quicktime movie).:


Instrument changes like these happen several times a month.


Time lapse movie of the Hale Telescope dome at night. (~36 mb Quicktime movie)

Historyof the Hale Telescope & Palomar Observatory

Adaptive Optics on the Hale Telescope

Re-aluminizing the 200-inch mirror

Re-aluminizing the Hale Telescope's secondary mirrors

  • Telescope Animations Light path - Telescope Motion - Dome Rotation
  • Virtual Tour : Visit the 200" prime focus cage with Jesse Greenstein

    The Hale Telescope at Palomar Observatory is operated as part of a collaborative agreement between the California Institute of Technology, its divisions Caltech Optical Observatories and the Jet Propulsion Laboratory (operated for NASA), and Cornell University.

    Choose one of the telescopes listed on the right to see images and learn more about another of  the Palomar Observatory's Telescopes.