Space

Has the 40-year old mystery of the "Wow!" signal been solved?

One of the most enduring astronomical mysteries may have finally been solved, as researchers find that comets are strong candidates for the famous Wow! signal
One of the most enduring astronomical mysteries may have finally been solved, as researchers find that comets are strong candidates for the famous Wow! signal
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One of the most enduring astronomical mysteries may have finally been solved, as researchers find that comets are strong candidates for the famous Wow! signal
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One of the most enduring astronomical mysteries may have finally been solved, as researchers find that comets are strong candidates for the famous Wow! signal

In August 1977, the Ohio State University Radio Observatory picked up a radio transmission from the Sagittarius constellation that was so strong it inspired the astronomer who discovered it to write "Wow!" in the margin of the data printout. Almost 40 years later, researchers from the Center for Planetary Science may have finally solved the mystery of the Wow! Signal's origin, and it's bad news for alien hopefuls: it was probably a comet.

At the time the signal was spotted, Ohio State's "Big Ear" observatory was specifically searching for transmissions that could be evidence of extraterrestrial civilizations. Based on the work of earlier astronomers, the team determined that a message of intelligent origin would most likely be transmitted at a frequency of 1,420 MHz – the electromagnetic frequency of hydrogen – and that the Big Ear would "hear" it for 72 seconds, since that's how long the observatory could focus on one specific point in space.

The Wow! signal was the first and only time exactly those criteria were met. Excited scientists tried training instruments on that region of space again, but the signal was never again recorded. Over the years, interference from Earth was ruled out, as were stellar bodies like planets, stars and asteroids. Aliens seemed unlikely, but tantalizingly, couldn't be ruled out.

Last year, a group of researchers from the Center of Planetary Science proposed a new hypothesis that argued a comet might be the culprit. The frequency could be caused by the hydrogen cloud they carry, and the fact that they move accounts for why it seemingly disappeared. Two comets, named 266/P Christensen and P/2008 Y2 (Gibbs), happened to be transiting through that region of space when the Wow! signal was detected, but they weren't discovered until after 2006.

To test the hypothesis, the team made 200 radio spectrum observations between November 2016 and February 2017. Sure enough, 266/P Christensen was found to emit radio waves at a frequency of 1,420 MHz, and to double check, the researchers moved their radio telescope by one degree. As expected, the signal vanished, and only returned when the telescope was trained back on the comet.

And 266/P Christensen wasn't an anomaly: the researchers tested three other comets, P/2013 EW90 (Tenagra), P/2016 J1-A (PANSTARRS), and 237P/LINEAR, and found they all emit signals at the same frequency.

Whether the Wow! signal was caused by 266/P Christensen or another comet, it seems that one of the most enduring astronomical mysteries has been put to rest.

The research was published in the Journal of the Washington Academy of Sciences.

Source: Center for Planetary Science

11 comments
McDesign
Man - that's - disappointing. Now how about that "Bloop" sound in the Pacific?
Vernon Miles Kerr
Wow! What if the supreme being went "eenie, meenie, miny.." and picked on small planet from amongst the trillion galaxies to create the only intelligent life in the universe? One would think that SETI would have come up with something by now...
LeoRodolfo
Yeah, right, it's a comet. Dude was probably watching some chick with a great caboose swinging it down the hall.
Kenlbear2
The next mystery: how does an iceball comet emit microwaves?
DetJohnMcClane
OK, queue the standard "wah, wah, waaaaaaah" sound of disappointment and failure. That's OK though. I don't mind my tax dollars being sent, literally in this case, into space, with very little prospect of a payoff. I just love how they predetermine parameters with information pulled from thin air, then get all excited when, on a purely random basis, they "hear" a signal matching those parameters. Un-effing-believable.
Bob809
I'm sorry to have to point this out, but- 'Almost 40 years later, researchers from the Center for Planetary Science may have finally solved the mystery of the Wow! Signal's origin, and it's bad news for alien hopefuls: it was probably a comet...' This is a such a contradictory headline and statement, especially from 'precise and provable over and over again' scientists. As usual, they come out with a crap statement to prove they still do not know what caused the signal, but feel a need to silence all those expecting it to be 'Alien.' Saying it was 'probably a comet' is not solved, as 'probably a comet' means they do not have a clue.
Mackey6000
Very interesting article. I appreciate this site for the unusual information
chase
👽👍
xLSDx
So clearly the aliens are equipping comets with death rays that resonate at the same frequency as hydrogen in order to camouflage their existence. Very clever.
GaryLesperance
Couldn't a similar algorithm tweaked for different gases be used to detect planets with an atmosphere similar to Earth?
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