spaceSpace and Physics

The Wow! Signal Sorted? Not So Fast!


Dr. Alfredo Carpineti

Senior Staff Writer & Space Correspondent

clockJun 8 2017, 17:54 UTC

The original scribble of the "Wow!" signal. The Ohio State University Radio Observatory/NAAPO

After we published an article about the famous Wow! signal likely being emitted by a comet, we were contacted by researchers from the Ohio State University Radio Observatory (responsible for the actual detection of the signal), who categorically refused the finding. They provided ample evidence that the comet claim is not as valid as we were led to believe. Actually, far from it.

The recent paper was peer-reviewed and published in the Journal of the Washington Academy of Sciences. It claims that Comet 266/P Christensen is likely the source of the Wow! signal observed almost 40 years ago.


Lead author Antonio Paris states in the paper: “On the same date and time, Comet 266P/Christensen was transiting in the vicinity where the “Wow!” signal was detected.” But as the astronomers at Ohio State University point out, this "vicinity" is very much a relative term for Paris.

The position of Comet 266/P the night of the detection was almost 15 degrees away from the position of the Wow! signal. This means that if you were staring at the location in the sky, it would take almost an hour from detecting the comet to eventually seeing the Wow! signal.

Paris also mentioned another potential culprit comet P/2008 Y2 (Gibbs) that he plans to observe next year. This object was also nowhere near the source of the signal.

Another issue pointed out in the rebuttal was that the author didn’t provide any spectral comparison between the Wow! signal and the alleged emission from the comet. The signal was of a very specific shape and it would be strong evidence if what Paris saw of the comet was indeed similar.


The scientists also pointed out that the emission from the source needs to be highly variable. The beam of the Big Ear, which detected the signal, was large enough to have the source in its field of view for several minutes. The researchers contacted several experts and each were unaware of any emission from comets like the one described by Paris.    

If all this wasn’t sufficient, the observatory had two side-by-side radio beams scanning the sky. If the source was a comet, it should have shown up in both of them. It did not.

We contacted the Journal of the Washington Academy of Sciences and asked if any of these issues were raised during the peer-review process, but at the time of writing, we have not received a reply.

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