Mount Laguna Observatory

9197-9999 Morris Ranch Rd
Mount Laguna, CA 91948


About Us:


Mount Laguna Observatory (MLO) is located forty-five miles east of San Diego, at an altitude of 6100 ft. (1859 meters) on the remote eastern edge of the Cleveland National Forest. MLO is well protected from the urban lighting of the San Diego metropolitan area. This remoteness, along with the high percentage of clear nights and excellent seeing, makes Mount Laguna one of the best overall observatory sites in the continental United States. MLO has grown to include four well-equipped telescopes, ranging in size from 21- to 50-inches (0.5- to 1.25-meters), which are used for research by the faculty and students. High-speed Internet connectivity is provided by the High Performance Research and Education Network HPWREN. The 50-inch Phillips Claud Telescope is now under construction. It will be housed in the dome of the original research telescope when the observatory was dedicated in 1968.

Images provided by, Ticketmaster
Please use "Flag This Place" to alert us about content that is inappropriate or needs immediate attention. Nothing you submit will be shared with other site visitors.

Upcoming AARP Events

View All AARP Events »

Find information about getting a COVID-19 vaccine in your state. CDC information is available at; additional AARP information and resources are at En español, visite

AARP Member Card

Join or Renew Today


  • Immediate access to your member benefits
  • Discounts on travel and everyday savings
  • Subscription to the award-winning AARP The Magazine
  • An ally on the issues that matter most to you in Mount Laguna
  • Free membership for your spouse or partner