Wow — Messages From Space
In 1977, the sound of extraterrestrials was heard by human ears for the first time — or so people at the time thought. The Wow! Signal was detected by astronomer Jerry Ehman using Ohio State University’s Big Ear radio telescope. It is a radio signal detector that, at the time, was pointed at a group of stars called Chi Sagittarii in the constellation Sagittarius.
When scanning the skies around the stars, Ehman captured a 72 second burst of radio waves: He circled the reading and wrote “Wow!: next to it, hence the signal’s name. Over the last 40 years, the signal has been cited as evidence that we are not alone in the galaxy. Experts and laypeople alike believed that, finally, we had evidence of alien life.
Astronomer Antonio Paris has been studying the Wow! signal for a long time. In 2016, he released a paper along with fellow astronomer Evan Davies suggesting that the signal could have been caused by a comet orbiting in the inner solar system. Specifically, the 2016 paper identified two comets, 266P/Christensen and P/2008 Y2 (Gibbs), that were both in the area where the Wow! signal was detected.
Both of these comets have large hydrogen clouds surrounding them that could produce the kind of signal detected in 1977. Paris spent about four months in late 2016 and early 2017 with a telescope pointed at comet 266P, and found strong signals of the same type as the Wow! signal.
Paris also examined several other similar comets and found the same type of hydrogen cloud and the same type of signal, which means that even if comet 266P wasn’t the specific source of the Wow! signal, another comet is most likely the culprit.
This is bad news for anyone holding out hope that the Wow! signal would be aliens, but it’s a solid conclusion to one of the biggest mysteries in astronomy. Now that we know comets can create these otherworldly signals, any future signals we get will have to be vetted much more carefully.
Other Extraterrestrial Communications
While this discovery is a disappointment to alien enthusiasts everywhere, as the Wow! Signal is the strongest signal we have ever received from space, it is a testament to our ability to accurately interpret signals and sounds from the cosmos. This gives us hope in our attempt to decode the hundreds of “strange, alien” signals coming from other stars that have been observed recently.
We have several weapons in our cosmic detection arsenal, most of which are used by the Search for Extra-Terrestrial Intelligence Institute (SETI). Their main means of detection is using radio-telescopes, and their most ambitious project to date has been ‘Project Phoenix’; the “world’s most sensitive and comprehensive search for extraterrestrial intelligence.”
For this project, they used three of world’s biggest radio telescopes: the Parkes radio telescope in Australia (210 feet in diameter), the National Radio Astronomy Observatory in West Virginia (140 feet in diameter), and Arecibo Observatory in Puerto Rico (the world’s largest at 1,000 feet in diameter). They have also built The Allen Telescope Array with financial backing from Paul Allen.
While the technology for detecting alien messages is remaining relatively static, ideas for communicating better with our own satellites is advancing rapidly, with possibilities including communicating by a laser beam and establishing a space satellite network.