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The Arecibo Observatory Celebrates 40 Years a Timeline

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The Arecibo Observatory Celebrates 40 Years a Timeline The Arecibo Observatory Celebrates 40 Years A Timeline 1958 1960 1964 1970 William E. Gordon, a Cornell Construction of the system The Arecibo Observatory begins First measurement of winds in University professor of electrical begins at Arecibo, Puerto Rico. producing data: the first incoher- the ionosphere. engineering, and his colleagues The first five Cornell families ent scatter measurements of the conceive of a very powerful radar arrive at Arecibo on July 1 and ionosphere and the first radar system, consisting of a giant open an office. detection of Venus. antenna and high-powered trans- mitter, for studies of the iono- sphere, the layer of the atmos- 1963 1965 phere 50 to 1,000 kilometers Astronomers determine the rota- (31 to 621 miles) above the Earth. The Arecibo Ionospheric Observatory is completed under tion rate of Mercury (the length Cornell's construction manage- of time it spins once on its axis), ment. The U.S. Advanced which is 59 days, two-thirds of Rober Research Projects Agency funds the planet's 88-day orbital period (the time it takes to orbit the t Barker / CU the project, the U.S. Air Force administers it, and Cornell man- Sun), meaning that the planet has 1971 ages the facility for the Air Force. just two days every three years. The National Science Foundation Intended for radar studies of the (NSF) assumes funding responsi- Earth's ionosphere, scientists bility for the Arecibo realize the telescope's impact Observatory. The Cornell-based National Astronomy and 1950sWilliam Gordon 1960sfor radio and radar astronomy, 1970s as well. Ionosphere Center (NAIC) is cre- ated to manage the huge radio telescope for the NSF. "When we were talking about building it back in the late '50s, we were told by eminent authorities it couldn't be done. ...We were in the position of trying to do something that was impossible... it took a lot of guts...we were young enough that we didn't know we couldn't do it. It took five Fast-moving pulsars—red years from idea to dedication, and that is short. But we lines; slower-moving pulsars—blue lines; were in the right place at the right time and had the right ordinary stars—black dots idea and the right preparation. We had no rules or precedents. ...These days if you proposed a big project it would take five years to get the committee appointed." William E. Gordon Professor Emeritus Rice University (Arecibo telescope designer and former Cornell engineering faculty) "It's really fascinating to see the development of this instrument and how it evolved in technology and how it's moved into new areas of science. Scientifically, it's very alive." Harold D. Craft, Jr. Vice President for Administration and CFO Cornell University CU (A former Cornell graduate student who did research on pulsars at the observatory from 1967 to 1969, former director of Arecibo, 1973–1981, and NAIC director for a year) Harold Craft, Jr. 1972 Late 1970s 1980s 1988 First detection of the high fre- Observations at Arecibo show Detailed maps are assembled Arecibo celebrates its 25th quency-enhanced plasma line in that galaxies are far more massive showing the filamentary nature anniversary. the ionosphere using the first than previously thought and are 1980sof the 3-D distribution of galaxies ionospheric modification facility largely made of "dark" matter, in the universe. in the United States. which cannot be seen directly. 1991 The first planets outside the solar Arecibo radar images of Venus 1982 system are discovered around a 1974 provide the first detailed look at Discovery of the first known OH pulsar by Alex Wolszczan, a staff First upgrade at the observatory, the surface of the planet and (hydroxyl) megamaser—a radio scientist at the observatory. costing $9 million and financed show that the age of the surface emission that is now known by the NSF and NASA, is com- is less than one billion years. often to be indicative of collisions pleted. The telescope's original between two galaxies. 1992 wire-mesh surface is replaced NAIC The second upgrade of the tele- Discovery of the first millisecond with 38,788 very accurately scope begins to facilitate observa- pulsar (a fast-spinning neutron shaped aluminum panels, allowing tions at frequencies up to 10 GHz star), PSR B1937+21. the telescope to operate at (3-centimeter wavelength) and frequencies as high as 3 gigahertz increase the sensitivity at all (GHz—billions of cycles per sec- frequencies. A new 1-megawatt ond) at a 10-centimeter wave- 1986 transmitter is planned for planetary length. A high-powered transmit- Arecibo Telescope Verification of the escape of radar observations and a dual ter (420 kilowatts) operating at hydrogen from Earth's exosphere beam capability for ionospheric 2.4 GHz is installed for planetary (the outermost region of the research. radar studies. atmosphere) using optical Fabry- Perot measurements. NAIC In a normal galaxy, baryonic matter—stars and interstellar gas and dust—resides deep inside a huge, massive envelope of dark matter, known as a "halo." Martha P. Haynes Astronomy, Cornell University Arecibo Telescope 1994 of the primary reflector, up to 10 Detection of the helium layer in GHz. The upgrade greatly increases "Allan [Allan Love of Rockwell the Earth's ionosphere. the telescope's sensitivity, frequency coverage, and agility, and enables International who designed the tele- dual-beam incoherent scatter radar scope's circular line feed] built a 1997 capability, providing new research line feed that still works perfectly. Completion of the second opportunities. upgrade of the telescope: The ...Yet it has never had a bath, and it $25 million cost was funded by The Angel Ramos Foundation has never melted." the NSF and NASA, with a Visitor and Education Center contribution from Cornell. opens to promote a greater public Astrophysicist Frank Drake It includes installation of a understanding of science. Professor Emeritus Gregorian reflector system, University of California, Santa Cruz which is suspended 137 meters (A former staff astronomer and director (450 feet) above the telescope's of the Arecibo Observatory) 305-meter-diameter (1,000-foot) NAIC dish, a 50-foot-high, steel wire mesh groundscreen around the perimeter of the dish, and a 1- megawatt radar transmitter. The 1990sGregorian reflector system allows Molecules play a key role in the telescope to operate over the full frequency range allowed by Visitor Center the structure and evolution of the accuracy of the 38,788 panels galaxies, stars, and planets, although it is surprising that molecules can exist in the harsh The Terzian research group plans to use environment of interstellar the sensitivity of the Arecibo radio space. How are they formed? telescope to survey the plane of the How do they survive? galaxy and map all the ionized radio- Paul F. Goldsmith emitting interstellar clouds. Astronomy, Cornell University Yervant Terzian Astronomy, Cornell University "...An important recipient of NSF's public investment in educational programs, in NAIC astronomical and atmospheric research, and in scientific facilities and infrastructure." Rita Colwell Director Gregorian Dome National Science Foundation (The funder of the Arecibo Observatory) 2000 2003 2005 NAIC First images of binary near-Earth Radar reveals the first evidence The NSF-funded, multimillion- asteroids, and the first measure- of liquid hydrocarbon lakes on dollar Arecibo L-band Feed Array, ments of micrometeor Titan, the largest moon of dubbed ALFA, will begin opera- decelerations. Saturn. A Cornell-led astronomy tion. The new instrument will team detects specular—or mir- greatly improve how radio rorlike—glints from Titan with astronomy research is conducted. 2002 properties that are consistent It will enable major survey proj- Arecibo Telescope Galactic turbulence, an ingredient with liquid hydrocarbon surfaces. ects of the heavens and will lead in cosmic cloud and star forma- Cornell astronomer Donald to a big increase in the volume tion, is discovered in starless Campbell, who led the observa- of astronomical data that will areas of the Milky Way. tion team, does not dismiss that flow from Arecibo. the reflections could be from Detection of interstellar very smooth, solid surfaces. micrometeors. November 1, 2003 Arecibo Observatory celebrates Rober The multiple feeds of the Arecibo its 40th anniversary. t Barker/CU L-band Feed Array (ALFA) will allow 2000s the sky to be surveyed faster and also provide the ability to remove radio frequency interference that can mimic pulsar signals. Donald Campbell James M. Cordes Astronomy, Cornell University Rober t Barker/CU "El radar Arecibo could be addressed as one of the most important classrooms in Puerto Rico. ...Here at Arecibo Observatory, many teachers, many students have enriched their capacity to see the world with imagination, with a sense of wonder, a sense of marvel." Attending the Arecibo celebrations were, from left, César A. Rey Hernández Cornell President Emeritus Dale Corson; Robert Brown, director of NAIC; Sixto González, director of Arecibo Secretary of Education Observatory; Robert Richardson, Cornell Vice Provost Puerto Rico for Research; and Joseph Burns, Vice Provost for Physical Sciences and Engineering Excerpts from news releases of the Cornell News Service.
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