urn:nasa:pds:context:telescope:arecibo.305m 1.1 1.21.0.0 Product_Context 2024-05-22 1.1 Updated to PDS IM v1.21.0.0. Corrected version_id. Added external references to NSF and Wikipedia web pages. Added content to Telescope:description. 2016-03-03 1.0 Initial version exported from OLAF urn:nasa:pds:context:facility:observatory.arecibo telescope_to_facility Arecibo Observatory (OLAF observatory code 240) urn:nasa:pds:context:instrument:arecibo.305m.trans_s telescope_to_instrument Arecibo Planetary Radar Transmitter urn:nasa:pds:context:instrument:arecibo.305m.recv_s telescope_to_instrument Arecibo Planetary Radar Receiver https://www.nsf.gov/news/special_reports/arecibo/Arecibo_Fact_Sheet_11_20.pdf Arecibo facts and figures: history and discoveries (through about 2017). https://en.wikipedia.org/wiki/Arecibo_Observatory Overview of Arecibo discoveries and history, including its collapse. 305 293.247306 18.344219 453.34 Geodetic - GRS 80 datum Arecibo's 305-m fixed spherical reflecting radio antenna was the primary telescope at Arecibo Observatory between 1963 and 2020, when it was irreparably damaged by a series of failures in its supporting cables. Because the surface was spherical, the antenna used 'line' feeds, each connected to receivers in 'carriage houses' supported above the reflector by towers and cables. In the late 1990s one of the carriage houses was replaced with reflecting optics that corrected the spherical aberration over a wide bandwidth, reduced receiver noise by a factor of several, and made gain less dependent on pointing. The antenna was 'pointed' over angles of approximately 0-20 degrees from zenith by by moving the carriage houses. Initially the antenna was used for radio astronomy above 50 MHz and solar system radar astronomy (including active probing of Earth's upper atmosphere) at 430 MHz. In the mid-1970s, the reflecting surface was improved and new receivers and transmitters were added, allowing radio observations to 11 GHz and radar operation at 2380 MHz. The position of the telescope was determined through surveying and comparison to stations determined using the Global Positioning System. The accuracy of the position is approximately 1m. Derived position in other coordinate systems: Geocentric Longitude: -66 45 09.70 Geocentric Latitude: +18 13 46.45 Astronomical Longitude: -66 45 08.00 Astronomical Latitude: +18 21 13.07 Elevation (above geoid): 496.84 m Geocentric X: 2390487.55 m Geocentric Y: -5564731.65 m Geocentric Z: 1994725.93 m