Located in southern California, the Palomar Observatory was established in 1948. It has a distinguished history as the site of tremendous astronomical innovation and discovery, and continues today as a world-class research center. The observatory is owned and operated by Caltech and is home to a suite of optical/infrared telescopes that are used nightly, not only as workhorses of modern astronomy, but also as active testbeds for instrument development.
The gem of the Palomar Observatory is the 200-inch Hale telescope - the world's largest until the Kecks came online in the 1990's. The Hale's diverse instrumentation suite is utilized by astronomers from Caltech, JPL, Cornell, and now the broader community through NOAO. The 60-inch and 48-inch Oschin telescopes have more specialized instrumentation with large blocks of time allocated to Caltech-led collaborations. Several smaller domes are also available for innovative uses and have hosted searches for comets, other solar system objects and transiting extrasolar planets.
The 200-inch Hale telescope is equipped with high-sensitivity, moderate-dispersion spectrographs in both the optical and near-infrared, together covering 0.3-2.5 microns and complementing two moderately wide field-of-view imagers for these same wavelengths. The science being pursued is wide ranging and includes the characterization of objects across the universe - from gamma ray burst afterglows, quasars, primeval galaxies, intermediate-redshift Type Ia supernovae, young star clusters, all the way to stellar populations in nearby galaxies, galactic star formation, nearby brown dwarfs, and solar system objects. The Hale's adaptive optics system (PALAO, built by JPL and currently being upgraded for significantly improved performance) corrects for the blur of astronomical targets caused by turbulence in the Earth’s atmosphere. This enables diffraction-limited resolving power of 0.025-0.050 arcseconds at near-infrared wavelengths. Taking advantage of these extremely sharp images are several instruments capable of suppressing starlight to reach contrast levels of 1:105 to 1:107, the main application being direct imaging searches for brown dwarf and planetary companions to nearby stars. Palomar is a world leader in adaptive optics technology development and science.
A number of scientific ventures are also being pursued on the smaller telescopes. For instance, the Palomar Transient Factory (PTF) is a fully-automated survey that utilizes the new wide-field camera on the robotic Palomar 48" as the discovery machine, then performs multi-band photometry on the robotic Palomar 60" to follow up discovered transients, and finally classifies the most interesting targets using the spectrographs on the Palomar 200" or the Keck Telescopes. The project is aimed at the systematic exploration of optical transients and is the first dedicated survey of its kind.
In addition to producing high impact science and training students in observations and instrumentation, the Palomar Observatory also hosts a prominent visitor center and education/outreach program in which Caltech students can participate.