The Wow! signal was an important clue for the potential of the existence of extraterrestrial intelligent life, the justification being that the signal was in such a pattern that it seemed unlikely for it to have been done by natural causes. This was championed by many people who believed in the possibility of aliens as some of the most solid evidence, as it is like hearing a click on the other line of a phone. But recent studies as of 2017 have posited that these signals could be the result of celestial bodies and their interactions

"

In 2016, we proposed a hypothesis arguing that a comet and/or its hydrogen cloud was a

strong candidate for the source of the “Wow!” Signal. From 27 November 2016 to 24 February

2017, we conducted 200 observations in the radio spectrum to validate the hypothesis. This

investigation discovered that comets 266/P Christensen, P/2013 EW90 (Tenagra), P/2016 J1-A

(PANSTARRS), and 237P/LINEAR emitted radio waves at 1420 MHz. In addition, the data

collected during this investigation demonstrated there is a well-defined distinction between radio

signals emitted from known celestial sources and comets, including comet 266/P Christensen.

We speculate that the strength of the original signal in 1977 would have been accounted

for by the size of the Big Ear Radio Telescope (when compared with Site B) and/or the potential

loss of mass from comet 266/P Christensen, which would have been considerably larger 40 years

ago. In addition, while neutral hydrogen clouds have been observed around other comets (mostly

from Lyman alpha spectra), determining the physical extent and density of the clouds around

comets 266/P Christensen, P/2013 EW90 (Tenagra), P/2016 J1-A (PANSTARRS), and

237P/LINEAR were not the purposes of this investigation. To dismiss the source of the radio signal

as emission from comet 266/P Christensen, we repositioned the telescope away from the comet

and conducted clear sky observations when the comet was not near the coordinates of the “Wow!”

Signal. During these clear sky observations, we detected no significant radio signal at 1420 MHz.

This investigation, therefore, has concluded that cometary spectra are observable at 1420 MHz and that the 1977 “Wow!” Signal was a natural phenomenon from a Solar System body.

"

The conclusion to the paper Hydrogen Line Observations of Cometary Spectra at 1420 MHZ by Prof. Antonio Paris a Adjunct Professor of Astronomy at St. Petersburg College

Hearing this a couple of months back was saddening to say the least, it genuinely felt like the closest we've ever got to proof and with further research it still seems in debate but unfortunately it seems to have been grabbed by people who don't seem to have the best of intentions and are instead using it for influence which is a shame as I saw no real paper disproving the possiblitiy of the comet theory, so I don't know.

We have to keep searching for more evidence, better and more conclusive than this, even if there may not be any.

The paper mentioned: http://planetary-science.org/wp-content/uploads/2017/06/Paris_WAS_103_02.pdf