All over social media, there are articles discussing radio signals from other galaxies and stellar systems. The number one rule in astrophysics and cosmology is – IT IS NEVER ALIENS. A lot of radio signals can be interpreted and can have natural sources; rapidly rotating neutron stars, supermassive black holes and so on.
So how do we receive radio signals? Through radio telescopes. Different universities, labs and agencies have large antenna telescopes that can pick up interstellar static and other strange vibrations in the cosmos. I have had the pleasure of listening to radio telescope transmissions during my research and it certainly wouldn’t be the most exotic or exciting forms of astronomy – in my humble opinion.
The best known organisation is the SETI institute – Search for Extra Terrestial Intelligence. Their main objective is to explore and observe regions of the universe with irregular or unusual radio wave bursts.
It’s important to distinguish between a radio burst and a radio signal. A radio burst can occur in stellar explosions/natural events whereas a radio signal implies the intention of contact or a message.
There are explanations for radio bursts although there are some signals that can not be ignored or tied to any cosmological phenomenon.
The most famous signal was detected on the 15th of August 1977 when the Big Ear Radio Telescope at Ohio State University heard a very unusual signal. The signal originated from the constellation Sagittarius and seemed to match the criteria for extra terrestrial contact.
The signal itself was able to be observed for a full 72 seconds and left the researchers quite baffled. In these instances, the scopes themselves are checked for electrical or software error. The Big Ear was perfectly functioning in subsequent tests.
A regular signal can be attached to natural phenomena and to date this signal has only been heard once. With newer and more modern scopes, a signal of this bandwidth and frequency has never been heard.
There are some that believe the WOW signal is some sort of message but no encoded information has been taken from the signal. The reason it is called the WOW signal is because researcher Jerry R. Ehman wrote “WOW!” beside the signal printout.
There have been some guesses as to the origin of this very strong signal. One being that an Earth based radio signal reflected off space debris and came straight back to Earth. Another being the reflection of the signal from hydrogen clouds or comet tails. Although from optical telescopes, no observations were made as to what debris or comet would have been within the beam of the radio telescope to reflect an Earth based signal back.
In the following 42 years since its discovery, there are no definitive answers as to what this signal actually is. It had never been relocated nor have we heard anything remotely similar. If it was a rare natural phenomenon to produce such a large signal, optical telescopes would be able to place a cause to it.
Remember – it’s never aliens!