The Hat Creek Radio Observatory (HCRO) is operated by the

SETI Institute The SETI Institute is a not-for-profit research organization incorporated in 1984 whose mission is to explore, understand, and explain the origin and nature of life in the universe, and to use this knowledge to inspire and guide present and futu ...

in the

Western United States The Western United States (also called the American West, the Western States, the Far West, the Western territories, and the West) is List of regions of the United States, census regions United States Census Bureau. As American settlement i ...

. The observatory is home to the

Allen Telescope Array The Allen Telescope Array (ATA), formerly known as the One Hectare Telescope (1hT), is a radio telescope array dedicated to astronomical observations and a simultaneous search for extraterrestrial intelligence (SETI). The array is situated at t ...

and one of the three CHIME FRB outriggers, as well a number of other smaller telescopes and instruments.

Location

Hat Creek Radio Observatory is located approximately northeast of

San Francisco, California San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of ...

at an elevation of 986 m (3235 ft) above

Sea Level Mean sea level (MSL, often shortened to sea level) is an mean, average surface level of one or more among Earth's coastal Body of water, bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical ...

in Hat Creek, California (in

Shasta County Shasta County (), officially the County of Shasta, is a county located in the northern portion of the U.S. state of California. Its population is 182,155 as of the 2020 census, up from 177,223 from the 2010 census. The county seat is Redding. ...

). Latitude: 40° 49' 03" N; longitude: 121° 28' 24" W. The nearest large city to Hat Creek is

Redding, California Redding is a city in and the county seat of Shasta County, California, and the economic and cultural capital of the Shasta Cascade region of Northern California. Redding lies along the Sacramento River, north of Sacramento, California, Sacrame ...

on highway I-5.

History

HCRO was founded in the late 1950s by the newly created

Radio Astronomy Laboratory The Radio Astronomy Lab (RAL) is an Organized Research Unit (ORU) within the Astronomy Department at the University of California, Berkeley. It was founded by faculty member Harold Weaver in 1958. Until 2012, RAL maintained a radio astronomy obser ...

(an Organized Research Unit of the Astronomy Department at the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California), is a Public university, public Land-grant university, land-grant research university in Berkeley, California, United States. Founded in 1868 and named after t ...

). An 85-foot antenna was installed in 1962 and operated until 1993, when it collapsed during a wind storm. Using it, astronomers discovered the first

astrophysical maser An astrophysical maser is a naturally occurring source of Stimulated emission, stimulated spectral line emission, typically in the microwave portion of the electromagnetic spectrum. This emission may arise in molecular clouds, comets, planetary at ...

. The university managed the facility until 2012, when SRI International assumed site management."UC Berkeley Passes Management Of Allen Telescope Array To SRI", Space Daily, April 19, 201

/ref> The SETI Institute started a refurbishment and upgrade program for the ATA in 2019, and in 2020 it also took over the operation of the observatory from SRI. The earliest experiments in millimeter-wave astronomy were performed at this site starting in the 1970s when a 2-element interferometer was constructed. From 1980 to 1985 a 3-element interferometer was constructed, with another four antennas added between 1990 and 1992. After the 85-foot dish was lost, another three antennas were added to the millimeter array for a total of 10 elements. This came to be known as Berkeley-Illinois-Maryland Association, BIMA. The BIMA telescopes were moved in the spring of 2005 to be combined with other millimeter antennas as part of the

Combined Array for Research in Millimeter-wave Astronomy The Combined Array for Research in Millimeter-wave Astronomy (CARMA) was an astronomical instrument comprising 23 radio telescopes, dedicated in 2006. These telescopes formed an astronomical interferometer where all the signals are combined in a ...

(CARMA) project and to make way for the

(ATA). Image:ATA350-render.jpg, Artist Rendering of completed ATA-350 Image:CARMA_Panoramic_cropped2.jpg, CARMA in D-array

References

External links

SETI Institute websiteHat Creek Radio Observatory Webpage
(Includes tour and contact info.)
Construction site satellite image from Google Maps
{{Portal bar, California, Astronomy, Stars, Spaceflight, Outer space, Solar System, Education, Science Astronomical observatories in California Buildings and structures in Shasta County, California Tourist attractions in Shasta County, California University of California, Berkeley SRI International