Wow! signal
The exact spot in the sky where the signal came from is unclear because of the design of the Big Ear telescope. The telescope had two different structures (called feed horns) that listened to the sky, and both listened to the sky in slightly different directions, and would be moved along the sky by the Earth's spin. The Wow! signal was heard in one of these feed horns, but not in the other, and the data was processed in a way that makes it is impossible to determine which of the two horns heard the signal. Making two different spots in the sky where the signal could have come from.