The OVRO 40 meter Telescope is a
radio telescope at the
Owens Valley Radio Observatory
Owens Valley Radio Observatory (OVRO) is a radio astronomy observatory located near Big Pine, California (US) in Owens Valley. It lies east of the Sierra Nevada, approximately north of Los Angeles and southeast of Bishop. It was established in 1 ...
near
Big Pine, California, US. It is owned and operated by
Caltech
The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...
. The telescope is easily visible from the section of
US highway 395
U.S. Route 395 (US 395) is a U.S. Route in the western United States. The southern terminus of the route is in the Mojave Desert at Interstate 15 near Hesperia. The northern terminus is at the Canada–US border near Laurier, where the road be ...
just north of Big Pine.
History
Construction of the telescope was funded by the
National Science Foundation
The National Science Foundation (NSF) is an independent agency of the United States government that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National ...
, as a prototype for a planned
astronomical interferometer at Owens Valley.
The interferometer was to incorporate eight dishes moving on
rails
Rail or rails may refer to:
Rail transport
*Rail transport and related matters
*Rail (rail transport) or railway lines, the running surface of a railway
Arts and media Film
* ''Rails'' (film), a 1929 Italian film by Mario Camerini
* ''Rail'' ( ...
, positioned up to apart.
[ The diameter prototype was completed in 1968, but by the end of the decade plans for the interferometer were cancelled in favour of the ]Very Large Array
The Karl G. Jansky Very Large Array (VLA) is a centimeter-wavelength radio astronomy observatory located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~ west of Socorro. The VLA comprises twent ...
.[
The newly-constructed prototype was instead combined with existing telescopes at Owens Valley to form a smaller interferometer, with maximum baseline of .][ Starting in 1969, it was also sometimes used as a ]very long baseline interferometry
Very-long-baseline interferometry (VLBI) is a type of astronomical interferometry used in radio astronomy. In VLBI a signal from an astronomical radio source, such as a quasar, is collected at multiple radio telescopes on Earth or in space. T ...
(VLBI) station, in conjunction with more distant observatories.[ When operating with the ]Parkes telescope
Parkes Observatory is a radio astronomy observatory, located north of the town of Parkes, New South Wales, Australia. It hosts Murriyang, the 64 m CSIRO Parkes Radio Telescope also known as "The Dish", along with two smaller radio telescopes. T ...
in Australia it provided the longest baseline then available in the world, and hence the highest angular resolution of 0.4 milliarcseconds
A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The n ...
.[ VLBI operations continued until 1991, when they were retired in favour of the more capable ]Very Long Baseline Array
The Very Long Baseline Array (VLBA) is a system of ten radio telescopes which are operated remotely from their Array Operations Center located in Socorro, New Mexico, as a part of the National Radio Astronomy Observatory (NRAO). These ten radi ...
.[
]
Current use
In 2007 the telescope was re-purposed for a dedicated blazar
A blazar is an active galactic nucleus (AGN) with a relativistic jet (a jet composed of ionized matter traveling at nearly the speed of light) directed very nearly towards an observer. Relativistic beaming of electromagnetic radiation from the ...
monitoring campaign, in support of the Fermi Gamma-ray Space Telescope
The Fermi Gamma-ray Space Telescope (FGST, also FGRST), formerly called the Gamma-ray Large Area Space Telescope (GLAST), is a space observatory being used to perform gamma-ray astronomy observations from low Earth orbit. Its main instrument is ...
which launched in 2008 and observes blazars in gamma ray
A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically ...
s. the telescope takes regular measurements of over 1800 blazars, by observing each one at twice a week.
In popular culture
Much of the 1996 film ''The Arrival'' was filmed at Owens Valley Radio Observatory, and the climactic fight scene occurred in, and on the primary mirror of, the 40 meter telescope.
See also
* List of observatories
This is a list of astronomical observatories ordered by name, along with initial dates of operation (where an accurate date is available) and location. The list also includes a final year of operation for many observatories that are no longer in ...
References
External links
The Owens Valley Radio Observatory
The OVRO 40M Telescope Fermi Blazar Monitoring Program
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Radio telescopes
Astronomical observatories in California
Buildings and structures in Inyo County, California