Table Mountain Observatory (TMO) is part of NASA JPL’s Table Mountain Facility, located above Wrightwood in the San Gabriel Mountains. The 37-acre site is situated at an elevation of 7,300 feet and overlooks the Mojave Desert, approximately 60 miles northeast of JPL’s Pasadena campus. Its high elevation, mountain setting, and distance from Los Angeles air pollution make it a prime location for astronomical and atmospheric research.
Building on this foundation, the site’s scientific history goes back further than most people think. The Smithsonian Institution started the observatory in 1926 to study solar radiation. In the late 1950s, JPL began using it to test solar panels for space vehicles and took over the U.S. Forest Service lease in 1962. That same year, JPL built TM-1, set up a 16-inch telescope, and saw its first light on August 1, 1962.
Beyond its original astronomical purpose, TMO’s primary focus is scientific research. In addition to astronomy, the Table Mountain Facility enables solar testing, spacecraft calibration, atmospheric lidar, and ozone and water vapor measurements. JPL’s lidar group values the site’s remote location, high altitude, favorable climate, and dark skies, which support research on stratospheric ozone, temperature, aerosols, tropospheric ozone, and water vapor.
In terms of significant equipment, a key modern telescope at TMO is Pomona College’s 1-meter (40-inch) telescope, which is shared with JPL. It has CCD imaging, filter wheels, polarimetry, near-infrared tools, and advanced adaptive optics. Built from 1982 to 1985, it got new optics in the 1990s and is now used for both student and research observations.
From a broader perspective, and from the viewpoint of someone in the Mojave or Wrightwood, Table Mountain Observatory stands out as a dedicated scientific station where the San Gabriel Mountains meet the desert sky. While places like Cajon Pass, Big Pines, and Angeles Crest are known for recreation, TMO’s main purpose is to support scientific research in the area.
Further reading: JPL Table Mountain Facility history, JPL Table Mountain lidar site, NDACC Table Mountain Facility station page, and Pomona College’s Table Mountain Observatory page.