The Arecibo Observatory is located approximately 9 miles south-southwest from Arecibo, Puerto Rico (near the extreme southwestern corner of Arecibo pueblo). It is operated by Cornell University under cooperative agreement with the National Science Foundation. The observatory works as the National Astronomy and Ionosphere Center (NAIC) although both names are officially used to refer to it. NAIC more properly refers to the organization that runs both the observatory and associated offices at Cornell University. Image File history File links Size of this preview: 757 × 600 pixelsFull resolution (1950 × 1545 pixel, file size: 3. ... Cornell University is a private university located in Ithaca, New York, USA. Its two medical campuses are in New York City and Education City, Qatar. ... The logo of the National Science Foundation The National Science Foundation (NSF) is an independent United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. ... The National Aeronautics and Space Administration (NASA) is an agency of the United States federal government, responsible for the nations public space program. ... Arecibo Observatory Nickname: La Villa del Capitán Correa Motto: {{{motto}}} Official website: ? Location Location within the nation of Puerto Rico Government Country Puerto Rico Mayor Lemuel Soto (PNP) Geographical characteristics Area 330. ... The wavelength is the distance between repeating units of a wave pattern. ... A spherical reflector is a reflector shaped like a portion of a sphere, so that light (or other electromagnetic radiation such as radio waves) from a point-source located at the virtual centre point of the sphere will reflect off the mirrored surface and back through the centre point of... Area is a physical quantity expressing the size of a part of a surface. ... The focal point F and focal length f of a positive (convex) lens, a negative (concave) lens, a concave mirror, and a convex mirror. ... The word transit, when used alone, has several possible meanings in English means of transport, including mass transit, rapid transit, public transit, public transport Further information: transit (transportation) in astronomy an event involving two bodies along the same line of sight Further information: astronomical transit in navigational position lines when... A primary mirror is a form of distributed data management on the Internet. ... A secondary mirror (or secondary) is a second light gathering and focusing surface in a reflector telescope. ... Military signalmen use hand and body gestures to direct flight operations aboard aircraft carriers. ... Arecibo Observatory Nickname: La Villa del Capitán Correa Motto: {{{motto}}} Official website: ? Location Location within the nation of Puerto Rico Government Country Puerto Rico Mayor Lemuel Soto (PNP) Geographical characteristics Area 330. ... There are no first-order administrative divisions as defined by the United States Government, but Puerto Rico has 78 municipalities at the second order. ... Cornell University is a private university located in Ithaca, New York, USA. Its two medical campuses are in New York City and Education City, Qatar. ... The logo of the National Science Foundation The National Science Foundation (NSF) is an independent United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. ... Molėtai Astronomical Observatory An observatory is a location used for observing terrestrial and/or celestial events. ...

The observatory's 305-m radio telescope is the largest single-aperture telescope (cf. multiple aperture telescope) ever constructed. It carries out three major areas of research: radio astronomy, aeronomy (using both the 305-m telescope and the observatory's lidar facility), and radar astronomy observations of solar system objects. Usage of the telescope is gained by submitting proposals to the observatory, which are evaluated by an independent board of referees. The 64 meter radio telescope at Parkes Observatory A radio telescope is a form of directional radio antenna most often used in radio astronomy and in tracking and collecting data from satellites and space probes (see Deep Space Network), and are also used in the SETI project. ... The Very Large Array, a radio interferometer in New Mexico, USA Radio astronomy is a subfield of astronomy that studies celestial objects in the radio frequency portion of the electromagnetic spectrum. ... Atmospheric sciences is an umbrella term for the study of the atmosphere, its processes, the effects other systems have on the atmosphere, and the effects of the atmosphere on these other systems. ... This article or section does not adequately cite its references or sources. ... Radar astronomy is a technique of observing nearby astronomical objects by reflecting microwaves off target objects and analyzing the echoes. ... Major features of the Solar System (not to scale; from left to right): Pluto, Neptune, Uranus, Saturn, Jupiter, the asteroid belt, the Sun, Mercury, Venus, Earth and its Moon, and Mars. ...

The telescope is visually distinctive and has been used in the filming of two notable motion pictures: as the villain's antenna in the James Bond movie GoldenEye and as itself in the film Contact. The telescope received additional international recognition in 1999 when it began to collect data for the SETI@home project. Flemings image of James Bond; commissioned to aid the Daily Express comic strip artists. ... GoldenEye is a 1995 spy film. ... Contact DVD Contact is a 1997 film adaptation of the science fiction novel Contact by Carl Sagan. ... SETI@home logo SETI@home (SETI at home) is a distributed computing project using Internet-connected computers, hosted by the Space Sciences Laboratory, at the University of California, Berkeley, in the United States. ...

General information

The Arecibo telescope is distinguished by its enormous size: the main collecting dish is 305 m in diameter, constructed inside the depression left by a karst sinkhole. The dish is the largest curved focusing dish on Earth, giving Arecibo the largest electromagnetic-wave gathering capacity. The Arecibo telescope's dish surface is made of 38,778 perforated aluminum panels, each measuring about 1 m by 2 m (3 ft by 6 ft), supported by a mesh of steel cables. Karst topography occurs when a landscape is marked by underground drainage patterns. ... Devils Hole near Hawthorne, Florida, USA. A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline (in the Slovene language dolina means valley) or cenote, is a natural depression or hole in the surface topography caused by the removal of soil or bedrock, often both, by... Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ...

It is a spherical reflector (as opposed to a parabolic reflector). This form is due to the method used to aim the telescope: the telescope's dish is fixed in place, but the receiver at its focal point is repositioned to intercept signals reflected from different directions by the spherical dish surface. The receiver is located on a 900-ton platform which is suspended 150 m (450 ft) in the air above the dish by 18 cables running from three reinforced concrete towers, one of which is 110 m (365 ft) high and the other two of which are 80 m (265 ft) high (the tops of the three towers are at the same elevation). The platform has a 93 m long rotating bow-shaped track called the azimuth arm on which receiving antennae, secondary and tertiary reflectors are mounted. This allows the telescope to observe any region of the sky within a forty degree cone of visibility about the local zenith (between -1 and 38 degrees of declination). Puerto Rico's location near the equator allows Arecibo to view all of the planets in the solar system, though the round trip light time to objects beyond Saturn is longer than the time the telescope can track it, preventing radar observations of more distant objects. A spherical reflector is a reflector shaped like a portion of a sphere, so that light (or other electromagnetic radiation such as radio waves) from a point-source located at the virtual centre point of the sphere will reflect off the mirrored surface and back through the centre point of... A parabolic reflector (also known as a parabolic dish or a parabolic mirror) is a reflective device formed in the shape of a paraboloid of revolution. ... Reinforced concrete at Sainte Jeanne dArc Church (Nice, France): architect Jacques Dror, 1926–1933 Reinforced concrete, also called ferroconcrete in some countries, is concrete in which reinforcement bars (rebars) or fibers have been incorporated to strengthen a material that would otherwise be brittle. ... Azimuth is the horizontal component of a direction (compass direction), measured around the horizon, from the north toward the east (i. ... In broad terms, the zenith is the direction pointing directly above a particular location (perpendicular, orthogonal). ... In astronomy, declination (abbrev. ... World map showing the equator in red In tourist areas, the equator is often marked on the sides of roads The equator marked as it crosses Ilhéu das Rolas, in São Tomé and Príncipe. ... Adjectives: Saturnian Atmosphere Surface pressure: 140 kPa Composition: >93% hydrogen >5% helium 0. ...

Design and architecture

A detailed view of the receiver array

The construction of the Arecibo telescope was initiated by Professor William E. Gordon of Cornell University, who originally intended to use it for the study of Earth's ionosphere. Originally, a fixed parabolic reflector was envisioned, pointing in a fixed direction with a 150 m (500 ft) tower to hold equipment at the focus. This design would have had a very limited use for other potential areas of research, such as planetary science and radio astronomy, which require the ability to point at different positions in the sky and to track those positions for an extended period as Earth rotates. Ward Low of the Advanced Research Projects Agency (ARPA) pointed out this flaw, and put Gordon in touch with the Air Force Cambridge Research Laboratory (AFCRL) in Boston, Massachusetts where a group headed by Phil Blacksmith was working on spherical reflectors and another group was studying the propagation of radio waves in and through the upper atmosphere. Cornell University proposed the project to ARPA in the summer of 1958 and a contract was signed between the AFCRL and the University in November of 1959. Cornell University published a request for proposals (RFP) asking for a design to support a feed moving along a spherical surface 435 feet above the stationary reflector. The RFP suggested a tripod or a tower in the center to support the feed. George Doundoulakis, director of research for the antenna design company General Bronze Corp in Garden City, N.Y. received the RFP from Cornell and studied it with his brother, Helias Doundoulakis, a civil engineer. Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1024 × 768 pixel, file size: 176 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1024 × 768 pixel, file size: 176 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... William E. Gordon is a physicist and astronomer. ... Relationship of the atmosphere and ionosphere The ionosphere is the uppermost part of the atmosphere, distinguished because it is ionized by solar radiation. ... Planetary science, also known as planetology or planetary astronomy, is the science of planets, or planetary systems, and the solar system. ... The Very Large Array, a radio interferometer in New Mexico, USA Radio astronomy is a subfield of astronomy that studies celestial objects in the radio frequency portion of the electromagnetic spectrum. ... The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense responsible for the development of new technology for use by the military. ... The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense responsible for the development of new technology for use by the military. ... Radio frequency, or RF, refers to that portion of the electromagnetic spectrum in which electromagnetic waves can be generated by alternating current fed to an antenna. ...

The two brothers thought of a more efficient way to suspend the feed, and finally designed the cable suspension system that was used in final construction. U.S. Patent office granted Helias Doundoulakis patent No. 3,273,156 on Sept. 13, 1966 with the title “Radio Telescope having a scanning feed supported by a cable suspension over a stationary reflector”.

Construction began in the summer of 1960, with the official opening taking place on November 1, 1963. As the primary dish is spherical, its focus is along a line rather than at a single point (as would be the case for a parabolic reflector), thus complicated 'line feeds' had to be used to carry out observations. Each line feed covered a narrow frequency band (2-5% of the center frequency of the band) and a limited number of line feeds could be used at any one time, limiting the flexibility of the telescope. November 1 is the 305th day of the year (306th in leap years) in the Gregorian calendar, with 60 days remaining. ... Year 1963 (MCMLXIII) was a common year starting on Tuesday (link will display full calendar) of the Gregorian calendar. ...

The telescope has undergone several significant upgrades over its lifespan. The first major upgrade was in 1974 when a high precision surface was added for the current reflector. In 1997 a Gregorian reflector system was installed, incorporating secondary and tertiary reflectors to focus the radio waves at a single point. This allowed the installation of a suite of receivers, covering the whole 1-10 GHz range, that could be easily moved onto the focal point, giving Arecibo a flexibility it had not previously possessed. At the same time a ground screen was installed around the perimeter to prevent receivers from sensing the ground (which, due to its temperature, would make observations less sensitive) and a more powerful transmitter was installed. The Gregorian telescope is a type of reflecting telescope designed by Scottish mathematician and astronomer, James Gregory in the 17th century. ...

Discoveries

The Arecibo telescope has made many significant scientific discoveries. On 7 April 1964, shortly after its inauguration, Gordon H. Pettengill's team used it to determine that the rotation rate of Mercury was not 88 days, as previously thought, but only 59 days. In 1968, the discovery of the periodicity of the Crab Pulsar (33 ms) by Lovelace and others provided the first solid evidence that neutron stars exist in the Universe. In 1974 Hulse and Taylor discovered the first binary pulsar PSR B1913+16, for which they were later awarded the Nobel Prize in Physics. In 1982, the first millisecond pulsar, PSR J1937+21, was discovered by Don Backer, Shri Kulkarni and others. This object spins 642 times per second, and it was until 2005 the fastest-spinning pulsar known. April 7 is the 97th day of the year in the Gregorian calendar (98th in leap years). ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... A sphere rotating around its axis. ... This article is about the planet. ... A neutron star is one of the few possible endpoints of stellar evolution. ... Russell Alan Hulse (born November 28, 1950) is an American physicist and winner of the Nobel Prize in Physics, shared with his thesis advisor Joseph Hooton Taylor Jr. ... Joseph H. Taylor, Jr. ... PSR B1913+16 is a pulsar in a binary star system, in orbit with another star around a common center of mass. ... Nobel Prize medal. ... A millisecond pulsar (MSP), often referred to as recycled pulsar, is a pulsar with a rotational period in the range of about 1-10 milliseconds. ...

In August 1989, the observatory directly imaged an asteroid for the first time in history: asteroid 4769 Castalia. The following year, Polish astronomer Aleksander Wolszczan made the discovery of pulsar PSR B1257+12, which later led him to discover its three orbiting planets (and a possible comet). These were the first extra-solar planets ever discovered. In 1994, John Harmon used the Arecibo radio telescope to map the distribution of ice in the poles of Mercury. 253 Mathilde, a C-type asteroid. ... The asteroid 4769 Castalia (previously known by the provisional designation 1989 PB) was the first asteroid to be directly imaged. ... Aleksander Wolszczan (b. ... It has been suggested that Radio pulsar be merged into this article or section. ... PSR 1257+12 (also catalogued as PSR B1257+12,PSR 1300+1240 and PSR J1300+1240) is a pulsar located 2630 light years from Earth. ... An extrasolar planet, or exoplanet, is a planet beyond the Solar System. ... This article is about the planet. ...

Other usage

The telescope also had military intelligence uses, for example locating Soviet radar installations by detecting their signals bouncing back off of the Moon. Arecibo is also the source of data for the SETI@home distributed computing project put forward by the Space Sciences Laboratory at the University of California, Berkeley and was used for the SETI Institute's Project Phoenix observations. Military intelligence (abbreviated MI, int. ... Soviet redirects here. ... This long range radar antenna, known as ALTAIR, is used to detect and track space objects in conjunction with ABM testing at the Ronald Reagan Test Site on the Kwajalein atoll. ... Shipmen on board the USS Hancock (CV-19) spelling out Moon Relay. ... Apparent magnitude: up to -12. ... SETI@Home under classic client (version 3. ... Distributed computing is a method of computer processing in which different parts of a program run simultaneously on two or more computers that are communicating with each other over a network. ... Sather tower (the Campanile) looking out over the San Francisco Bay and Mount Tamalpais. ... The SETI Institute is a private, nonprofit organization dedicated to scientific research, education and public outreach to explore, understand, and explain the nature and origin of the Universe. ... Project Phoenix is a SETI project: a search for extraterrestrial intelligence by listening for radio signals. ...

In 1974, the Arecibo message, an attempt to communicate with extraterrestrial life, was transmitted from the radio telescope toward the globular cluster M13, about 25,000 light-years away. The 1,679 bit pattern of 1s and 0s defined a 23 by 73 pixel bitmap image that included numbers, stick figures, chemical formulas, and a crude image of the telescope itself. Arecibo Observatory This is the message with color added to highlight its separate parts. ... Messier Object 13, the Great Globular Cluster in Hercules; one of the most prominent and best known globular clusters of the Northern celestial hemisphere. ... This article is about the unit of information. ... For the use of the term raster in radio regulation, see frequency raster. ...

Terrestrial aeronomy experiments include the controversial (Ruiz 1998) Coqui 2 experiment (Friedlander 1997). The Coqui and Coqui 2 (Coqui Dos) campaign involved a sequence of sounding rocket launches in order to study the dynamics of the E- and F-region ionosphere and increase our understanding of layering phenomena, such as sporadic E layers. ...

Arecibo in popular culture

Arecibo Observatory was used as a filming location in the final scene of the James Bond movie GoldenEye. In the film, the villain Alec Trevelyan used a similar dish in Cuba to communicate with a Russian satellite to fire an electromagnetic pulse at London. The dish and the ground below it could be covered with water to conceal it as a lake. Additionally, the use of Arecibo to communicate with an earth-orbiting satellite is nonsensical from a technical standpoint. Flemings image of James Bond; commissioned to aid the Daily Express comic strip artists. ... GoldenEye is a 1995 spy film. ... Alec Trevelyan (006) is the primary villain in the James Bond film GoldenEye, portrayed by actor Sean Bean and is based on The Stourport Psycho Michael Waldron also known in the underworld as Mickey Woosh. ... Example of an electromagnetic pulse, in this case caused by the electrical discharge required to fire the Z machine. ...

The observatory was also featured in a segment of a Reading Rainbow episode. The Reading Rainbow logo used between 1999 and 2007. ...

In the X-Files episode "Little Green Men", Fox Mulder was sent to the Arecibo Observatory by a U.S. Senator because contact had been made with extraterrestrial life. As was often the case in the series, Mulder was forced to escape as U.S. government military forces arrived, without taking definitive proof of alien contact with him. X-Files intro from first 8 seasons The X-Files was a popular 1990s American science fiction television series created by Chris Carter. ... Little Green Men was the first episode of the second season of The X-Files science-fiction television series created by Chris Carter. ... Special Agent Fox William Mulder (born October 13, 1961), nicknamed Spooky Mulder, is a fictional character played by David Duchovny on the 1993-2002 television series, The X-Files. ... Federal courts Supreme Court Chief Justice Associate Justices Elections Presidential elections Midterm elections Political Parties Democratic Republican Third parties State & Local government Governors Legislatures (List) State Courts Local Government Other countries Politics Portal      The United States Senate is one of the two chambers of the bicameral United States Congress, the... A 1967 Soviet Union 16 kopeks stamp. ... ...

The film Contact features Arecibo in a more life-like way, as main character Ellie Arroway uses the facility as part of a SETI project. Contact DVD Contact is a 1997 film adaptation of the science fiction novel Contact by Carl Sagan. ... This article is about the search for extra-terrestrial intelligence. ...

The Arecibo Observatory was also featured in the film Species, as the main setting for the James Gunn novel The Listeners (1972), and as a prominent element in the Mary Doria Russell novel The Sparrow (1996). Species is a 1995 science fiction thriller. ... James Edwin Gunn (born 1923 in Kansas City, Missouri) is an American Science Fiction author, editor, scholar, and anthologist. ... Mary Doria Russell (born 1950) is an American author of science fiction. ... The Sparrow (1996) is the first novel by science fiction author Mary Doria Russell. ...

The aliens in the BBC radio serial Space Force (1984) contact Earth after receiving the Arecibo message. One of the characters in the episode "The Voice from Nowhere" says that the Arecibo Observatory was closed down and dismantled. A BBC Radio science fiction serial written by Charles Chilton which ran for two years, a sequel to the 1950s serial Journey Into Space. ...

Songwriter and author Jimmy Buffett mentions the "giant telescope" in his book Where Is Joe Merchant?, and in the lyrics to the song "Desdemona's Building A Rocket Ship". In both, a talented baker and former backup singer named Desdemona has a tryst with one of the workers "under the giant telescope", and begins receiving telepathic messages from the Pleiades, telling her to build a spaceship and "come home". This article needs additional references or sources for verification. ... Where is Joe Merchant? is a book by Jimmy Buffett which was published in 1992. ... Pleiades refers to: Pleiades (star cluster) an open cluster of stars in the constellation Taurus. ...

Funding issues

A report by the division of Astronomical Sciences of the National Science Foundation, made public on 2006-11-03, recommended substantially decreased astronomy funding for Arecibo Observatory, ramping down from USD 10.5M in 2007 to USD 4M in 2011. If other sources of funding cannot be obtained, the telescope will be shut down in 2011. The report also advised that 80% of the observation time be allocated to the surveys already in progress, reducing the time available for other scientific work. If the additional funding is not available, Arecibo's radar astronomy program will cease October 1 2008. Subsequent discussions during town hall meetings in Arecibo and San Juan held in late June, 2007 revealed that the decision about closure will occur in 2009. At the meetings, Puerto Rico Senate President Kenneth McClintock announced an initial local appropriation of $3 million during fiscal year 2008 to fund a major maintenance project to restore the three pillars from which the antenna platform is suspended to their original condition, pending inclusion in the territorial government's next bond issue. The appropriation would be the first time that the island's government contributes financially to the operation of a federal installation. For the Manfred Mann album, see 2006 (album). ... is the 307th day of the year (308th in leap years) in the Gregorian calendar. ... Radar astronomy is a technique of observing nearby astronomical objects by reflecting microwaves off target objects and analyzing the echoes. ... Kenneth McClintock, President of the Senate of Puerto Rico. ...

See also

• List of radio telescopes
• Sixto Gonzalez, former director of Arecibo Observatory
• Arecibo message

See also List of observatories Radio telescopes A more complete list of radio telescopes can be found by looking at the radio telescopes category External links AstroSurf. ... Dr. Sixto Gonzalez (b. ... Arecibo Observatory This is the message with color added to highlight its separate parts. ...

References

1997 (MCMXCVII) was a common year starting on Wednesday of the Gregorian calendar. ... November 14 is the 318th day of the year (319th in leap years) in the Gregorian calendar. ... Year 1998 (MCMXCVIII) was a common year starting on Thursday (link will display full 1998 Gregorian calendar). ... March 3 is the 62nd day of the year in the Gregorian calendar (63rd in leap years). ... For the Manfred Mann album, see 2006 (album). ... is the 295th day of the year (296th in leap years) in the Gregorian calendar. ... For the Manfred Mann album, see 2006 (album). ... November 6 is the 310th day of the year (311th in leap years) in the Gregorian calendar. ...

External links

• Arecibo Observatory official site
• SETI@home official site
• IEEE History Center - IEEE Milestones: NAIC/Arecibo Radiotelescope
• Lofar
• Google Maps

Coordinates: 18°20′39″N, 66°45′10″W Map of Earth showing lines of latitude (horizontally) and longitude (vertically), Eckert VI projection; large version (pdf, 1. ...