Astronomer Jerry R. Ehman worked as a volunteer analyst for the Search for Extraterrestrial Intelligence (SENTI) project. Each day, he sat in a small, dark, and quite depressing room while he silently reviewed recorded data from the Big Ear radio telescope, which documented signals that were received from outer space. In contrast to the typical signals he continually observed, on August 15, 1977, Ehman noted an unusually strong transmittance coming from far off in the Sagittarius constellation. This shocked him wide awake from his rather boring routine. This was huge. In the midst of his nerdy excitement, he circled the “6EQUJ5” response and shakily scribbled “Wow!” in bright red pen in the margins.

To the general population, the Wow! signal appears to be meaningless–a random jumble of letters and numbers, perhaps a game of Scrabble gone horribly wrong–and it is in the linguistic sense. However, what had caught astronomers’ and conspiracy theorists’ attention those 40 years ago was the abnormal strength and brief length of the transmission, ruling out terrestrial origin and all other known entities in our solar system.

Until halfway through 2017, the Wow! mystery remained unexplained. Many conspiracy theorists were left in the dark wondering about the message’s source and purpose, with most stating that extraterrestrial life could have been the only possible cause. After extensive research, Center of Planetary Science’s (CPS) Antonio Paris and others from his team proposed that two comets had generated the Wow! Signal decades earlier.

The 1977 signal was transmitted at a frequency of 1,420 MHz, which is the same as the element hydrogen’s own frequency. This newfound information led CPS to investigate hydrogen gas containing comets, specifically 266P/Christensen and 335P/Gibbs, which remained undiscovered until 2006. Paris and his research team were able to deduce that the pair of comets would have been in the area that was viewed by the Big Ear on August 15 at the perfect moment.

Since they were unknown at the time, it makes total sense that scientists ruled out all entities in the solar system and made no move to further investigate the strange occurrence. The CPS team then recreated the Big Ear set up in perfect imitation of the past and managed to record signals transmitted by the comets as they passed over at the Wow! location.

Just as predicted, the data received was exactly the same as the set 40 years prior.

Despite the above, concrete evidence, Ehman and numerous other skeptics continue to discount the comet idea because the results do not account for why the signal occurred for such a short period of time and did not repeat. Since the Big Ear had “two horns” that recorded two different areas, the source should have “come through twice in about three minutes.” Considering this did not occur, Ehman claims that the Wow! signal was cut off abruptly, which would not happen if the source was the surrounding gas of a comet. In response, Paris proposes that the Big Ear might have glitched when recording, which “some data out there [seems] to suggest.”

The comets are the most logical explanation for the Wow! signal and one that humanity should hope to be true. Because if it were Aliens that transmitted the signal in 1977, they have not wanted to contact us since.