The strange sign was picked up by Ohio State University’s Big Ear radio telescope. However, scientists did not notice anything out of the ordinary until a few days later when reviewing the data. The entire signal sequence, spotted by Dr Jerry Ehman, lasted for 72 seconds and was a “loud” noise at a frequency of around 1,420 megahertz.
However, he, alongside all his colleagues, could not give a reasonable explanation for it in 1979 and that is still the case today.
Dr Ehman was so shocked, he circled the reading on the computer printout and wrote the comment: “Wow!”
To this day, it has been known as the strongest candidate for an alien radio transmission to Earth.
Speaking about the signal in 2014, Professor Brian Cox claimed: "If an alien civilisation wanted to communicate with us, this is exactly how they would do it."
A number of theories attempting to explain the Wow! signal have emerged over the years but none of them have achieved widespread acceptance.
The Wow! signal was spotted in 1979 (Image: YOUTUBE/GETTY)
Dr Ehman circled the signal (Image: BBC)
If an alien civilisation wanted to communicate with us, this is exactly how they would do it
In 2017, astronomer Antonio Paris proposed