Crucially, this feature was not yet installed in 1977 so the telescope swept across the Wow! signal for the duration of its detection. This allowed the telescope to fix its view on the sky at any given point when an interesting signal was detected, compensating for the movement of the Earth's rotation, and allowing a single spot to be studied for a time. In 1980, a feature was added to the Big Ear that could have come in very handy when the Wow! signal was detected and that was a set of tracks upon which the receiving horns could move east or west across the face of the flat reflector. John Kraus who designed it and came up with its $250,000 cost, including a $71,000 grant from the National Science Foundation. The Big Ear's design was called a Kraus telescope, after Ohio State's Dr. After a few days of data gathering, the flat reflector could be tilted a tiny bit, moving that line of study up or down across the sky. As the Earth rotated, the Big Ear swept the sky in a single line. This reflector received the signal bouncing off a tiltable flat reflector spanning the north end, just beyond the receiving horns, 104 meters by 30 meters. They were at the focus of a great paraboloidal reflector, 110 meters by 21 meters, standing across the southern end like a giant curved movie screen. Near the middle of its north end were a pair of receiving horns, looking like giant foghorns, pointing south. Its main feature was a vast aluminum ground plane, 150 meters by 85 meters, about three times the area of an average professional soccer pitch, and aligned north-south. The telescope no longer exists, having been disassembled in 1998 and its acreage used to expand a neighboring golf course. Ohio State's "Big Ear" radio telescope was, well, big. To understand where the signal came from, and (at least as importantly) how we know where it came from, it's necessary to understand the workings of the interesting radio telescope that received it. When you hear about the Wow! signal, one of the most important and obvious questions to ask is where it came from, and what's there. The longest single search project was carried out by Ohio State University, from 1972 to 1997. Virtually every radio telescope is used at least part time by some group scanning the skies looking for signals that might come from some interstellar source. For a long time, many different organizations have engaged in their own searches, but there's no central authoritative project. SETI stands for the search for extra-terrestrial intelligence, but there is no single SETI group. All speculation and hype aside, Wow! remains the strongest candidate ever detected for an alien radio transmission. The strength of the signal was represented by the digits 0-9 and the letters A-Z, a scale of 36 levels of intensity, rising with 6EQ and falling with UJ5, a near-perfect bell curve of signal strength spread over 72 seconds. It came from the direction of Sagittarius. It was, apparently, a signal from outer space. So much so, in fact, that he circled the text, and wrote "Wow!" in the margin. In a moment that's since become one of the most famous events in astronomy, he saw a sequence of six characters on the printout - 6EQUJ5 - which caught his attention. It was August 15, 1977, when astronomer Jerry Ehman was examining data coming from Ohio State University's radio telescope, which was engaged in listening for signals from deep space, hoping to find something of intelligent origin.
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