The Wayback Machine -


Look Beyond Earth at the Arecibo Observatory

Have you ever wondered what lies beyond the planet Earth? Do you want to know how many exoplanets potentially existing beyond our solar system? Do you want to discover "are we alone in the universe?" or, "is there alien life occurs outside of Earth?" Well, your quest for exploring space, figuring out origin of life on Earth, and possibilities of alien life in the universe ends here at the Arecibo Observatory, the largest radio telescope on earth located in Arecibo, Puerto Rico.

Constructed in the 1960s until 2011, the observatory is used to explore the wonders of the universe and study the ionized part of the Earth's atmosphere and spot distant planets when they pass overhead. The world’s largest fully operational radio telescope – the Arecibo Observatory - is conceived by William E. Gordon, a former Cornell electrical engineering professor, in 1960, and is operated and managed by University of Central Florida, Universidad Metropolitana (UMET) in San Juan and Yang Enterprises, Inc. in Oviedo, under cooperative agreement with the National Science Foundation (NSF). The observatory is the one and only facility of the National Astronomy and Ionosphere Center (NAIC).

The observatory has a massive concrete bowl lying between the foothills along the northwestern part of the island. It is the largest single-dish radio telescope in the world with the main reflector dish measuring 305 meters (1000 feet) in diameter, 51 m (167 feet) deep, and covering an area of 18 acres. Initially, the fixed spherical telescope’s surface consisted of half-inch galvanized wire mesh placed directly on the support cables and its highest expected operating frequency was approximately 500 MHz. Later, in 1974, the old wire mesh was replaced with a high-precision surface consisting of 40,000 individually adjustable aluminum panels, and the maximum usable frequency was increased to about 5000 MHz. The radars can receive signals from 25 megahertz to 10 gigahertz. Arecibo Observatory's four transmitters consist of an S-band 2,380-MHz radar system for planetary studies and a 430-MHz radar system for aeronomy programs. Since 1997, a Gregorian reflector system has been hanging from the main detector area 137 meters (450 feet) above the gigantic reflector dish.

With its incredible sensitivity, the observatory’s radar system gathers information about planets, moons, asteroids and comets. Because the Arecibo Observatory has the world’s most powerful single-dish radio telescope, it is also used as a visitor-oriented national research center, offering scientists an opportunity to explore radio astronomy, study space sciences & atmospheric science, as well as track potentially dangerous objects hanging near the Earth and conduct planetary radar research. Apart from providing a valued scope for space science, the observatory also creates academic opportunities for students and faculty at UCF, and outsiders. Hundreds of international scientists travel from throughout the world to use this telescope to find far away galaxies and learn about the sun and stars as well as make observations and conduct all sorts of science research.

Since its inception, the observatory has made significant contributions to science and understanding the universe. Scientists from around the world have used the Arecibo telescope to gather radio signals from star-forming regions in our galaxy, and areas of the celestial sphere within which planets are formed, as well as study the radio emissions from distant galaxies, quasars and the atmosphere. This huge scientific instrument has made many considerable scientific discoveries. Using the observatory, on April 7, 1964, an American radio astronomer and planetary physicist, Gordon Pettengill and his team established that the true rotation period of Mercury was only 59 days, and not 88 Earth days, as previously thought. In August 1989, the Arecibo telescope directly imaged an asteroid for the first time in history known as 4769 Castalia. The Observatory’s ultra advanced radar imaging enabled American scientists Scott Hudson and Steven Ostro to produce a three-dimensional model of the peanut-shaped 4769 Castalia.

In 1974, using the Arecibo telescope, American physicist Russell Alan Hulse and American astrophysicist Joseph Hooton Taylor discovered the first binary pulsar PSR B1913+16, which has a white dwarf or neutron star nearby that moves around the pulsar. The scientist duo received the Nobel Prize in Physics for this accomplishment in 1993. In 1983, the first millisecond pulsar, known as PSR B1937+21, was discovered by Miller Goss, Michael Davis, Carl Heiles, Shrinivas Kulkarni and Donald C. Backer using Arecibo’s telescopes. This pulsar spins about 642 times a second. So far, scientists have found nearly 200 more fast-spinning pulsars in the universe.

In 2008, the telescope was used to detect prebiotic molecules methanimine and hydrogen cyanide in a distant starburst galaxy Apr 220, which is about 250 million light-years from Earth. This discovery has greatly contributed to the simmering debate of finding life elsewhere in the universe. Between January 2010 and February 2011, bursts of radio emission from the T6.5 brown dwarf 2MASS J10475385+2124234 were detected by American astronomers Matthew Route and Aleksander Wolszczan. Most recently, in June 2012, Arecibo’s S-band planetary radar system demonstrated that near-Earth asteroid 2005 YU55 is in fact 2 times larger than formerly thought.

The breathtaking discoveries and findings made using the Arecibo Observatory over the years have significantly contributed to better understanding of the moon, exotic stars, solar system, asteroids, our galaxy, other planets, earth’s atmosphere etc. Besides its scientific operations, the gigantic most sensitive telescope at the Arecibo Observatory has appeared in films, novels and television productions as well. It was featured prominently in the climax part of 1995 James Bond film "Goldeneye," starring Pierce Brosnan. The observatory can also be seen in the film Contact (1997), and in The X-Files episode, "Little Green Men" (Season 2, Episode 1). It is also featured as a level in the 1997 Nintendo 64 video game ‘GoldenEye 007’ and the 2010 open world action-adventure video game 'Just Cause 2'.

Since 1999, the telescope has been instrumental in collecting data for the SETI@home project, a free screen-saver program that sieves data from the Observatory in search of a signal from the stars. In January 2014, an earthquake caused a serious damage to the Arecibo Observatory. Again in September 2017, Hurricane Maria slammed the radio telescope, which tore off few of its panels and broke one of the telescope’s two 430MHz radars. However, the telescope was still fully operational. The Arecibo Observatory will continue to marvel scientists with spectacular discoveries for generations to come, we hope.

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