Astronomical Observatories in Puerto Rico - Arecibo Observatory (Paperback)

Chapters: Arecibo Observatory. Source: Wikipedia. Pages: 18. Not illustrated. Free updates online. Purchase includes a free trial membership in the publisher's book club where you can select from more than a million books without charge. Excerpt: Arecibo Observatory - Opened in 1997, the Angel Ramos Foundation Visitor Center features interactive exhibits and displays about the operations of the radio telescope, astronomy, and atmospheric science. The center is named after the foundation created by Angel Ramos, the founder of Telemundo, which provided one half of the construction costs for building the center. The Arecibo telescope is distinguished by its enormous size: the main collecting dish is 305 m (1,001 ft) 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, 1 yd by 2 yd), supported by a mesh of steel cables. The telescope has three radar transmitters, with effective isotropic radiated powers of 20TW at 2380 MHz, 2.5TW (pulse peak) at 430 MHz, and 300MW at 47 MHz. The telescope 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, and the receiver is repositioned to intercept signals reflected from different directions by the spherical dish surface. A parabolic mirror would induce a varying astigmatism when the receiver is in different positions off the focal point, but the error of a spherical mirror is the same in every direction. The receiver is located on a 900-ton platform which is suspended 150 m (500 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 othe...More: http: //booksllc.net/?id=159191