The Big Ear fell victim to funding cuts followed by unsympathetic developers who dismantled it in 1998 to extend a golf course, which was perhaps the unkindest cut of all. This is actually pretty important because it is then possible to discern interesting signals that originate from a point ('What's your sign?') from those that are just part of the general hubbub ( 'Chugalug! Chugalug! Chugalug!') since general hubbub pretty much reaches both ears at once. Consequently, just as words from the mouth of a particular party-goer would first reach our left ear, say, and then our right as we turned round, so a radio signal from a patch of sky would first enter one horn and then the other. The focused beam was directed to two horns. The tiltable reflector did, however, allow it to also 'look' higher or lower in the sky. Just as our ears are attached to our head and can only passively scan a party for interesting conversations when we turn our head, so the Big Ear was affixed to the Earth and scanned the sky due to the Earth's rotation. In all, the Big Ear covered a somewhat greater area than eight Olympic-sized swimming pools would. These reflectors were separated by a 360-feet-wide by 500-feet-long ground plane (picture an aluminium carpet). Incoming radio signals were bounced off a 340-feet-long by 100-feet-high flat rectangular tiltable reflector over to a 360-feet-long by 70-feet-high curved reflector shaped as a paraboloid that focused the incoming radio beam. Construction began on the grounds of the Ohio Wesleyan University in autumn, 1956 and reached completion in 1963. The idea for the Big Ear radio telescope was conceived by the late Dr John D Kraus and appeared in the March, 1955 issue of Scientific American. Many radio astronomers have since joined him at the waterhole. Alas, his hair colour continued to fade, but it was an event that nonetheless galvanised his resolve to continue the search. To his disappointment, however, the signal persisted as he turned the telescope from the Pleiades which indicated that it did not in fact emanate from the sky after all. His initial thought was that it must be intelligent and the shock of it started turning his hair prematurely white. While at Harvard in 1955, renowned radio astronomer Frank Drake was measuring the radio spectrum of the Pleiades cluster in Taurus when he found a strong signal in this band that seemed entirely too regular. Due to the importance of the hydrogen line band to radio astronomy (21.4cm-21.0cm), for example, no licences are given for its use - so presumably signals received in this range should only originate from the sky. Given that we have to start somewhere, a waterhole seems a logical place to look for life. In this configuration, the two don't actually combine to form water, but for aesthetic reasons the region has been called 'the waterhole'. The WaterholeĮarly on, interest focused on the region of the radio spectrum between 21cm (the wavelength of the radio signal emitted by the hydrogen atom) and 18cm (that emitted by the OH molecule, also known as the hydroxyl radical). In this case, the search is for radio signals that are both incoming and intentional. What to search for is the first one of those choices. So it is with the Search for Extra Terrestrial Intelligence that some choices have to be made. He is found looking for them under the street lamp because, of course, he wouldn't be able to see them anywhere else. Searching for life, but not as we know it, presents the same problem for us as for the drunk who has lost his keys late at night. It should be noted that on the very next day Elvis left the planet having earlier said: 'This is gonna be my best tour ever.' Elvis remains an enigma too, but perhaps for different reasons. However, on 15 August, 1977, it received and recorded what became known as the 'Wow!' signal - a signal that remains both an enigma and the most credible candidate for an actual transmission from extra-terrestrial intelligence. Or used to have, we should say, because the Big Ear radio telescope is no longer.
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