ELI5: Explain Like I'm 5

Wow! signal

The Wow Signal was a very strong radio noise that was picked up by a telescope in Ohio in 1977. Scientists believe that it could have been from an alien civilization, but they can't be sure. As the signal was only heard once, it's been impossible for them to study it in order to learn more about it. Some people think it might have been a message from an alien civilization to try and contact us, but no one knows for sure!