The wow! Signal - Strongest evidence of intelligent alien life.

By the word signal you may think that its just a type of signal but you will be amazed when you will know that this signal was coming from an alien world. This 72 seconds long signal was considered as the strongest evidence of existence of intelligent alien life.

  This signal was detected by Jerry R. Ehman on August 15, 1977, while he was working on a SETI project at the Big Ear radio telescope of Ohio State University. Amazed at how closely the signal matched the expected signature of an interstellar signal in the antenna used, Ehman circled the signal with the word "wow!".

  The signal remained 72 seconds as the area of sky from where the signal was coming from was searched but no such signal was detected back again. The Big Ear could observe any given point for just 72 seconds. A continuous extraterrestrial signal, therefore, would be expected to register only 72 seconds long. and the recorded intensity of signal should show a gradual increase for first 32 seconds —peaking when the signal reached the center of Big Ear's observation "window"— and then a gradual decrease. Therefore, both the length of the Wow! signal, 72 seconds, and the shape of the intensity graph may correspond to an extraterrestrial origin.

The locations of signal in the constellation of sagittarius. 

  The signal was coming from the constellation sagittarius, 2.5 degrees south of the fifth-magnitude star group Chi Sagittarii, and about 3.5 degrees south of the plane of the ecliptic . Tau Sagittarii is the closest easily visible star.

  Some claims that the signal was not other than a reflected back signal of earth which collided with a object in space and then returned back and mistakenly considered as alien signal. Despite this claims the signal was considered as the strongest evidence of existence of intelligent alien life.

  35 years later in 2012, Arecibo Observatory beamed a response from humanity, containing 10,000 Twitter messages, in the direction from which the signal was coming from.

Source of information : Wikipedia