Australian Telescope Just Scanned 10 million Stars For Any Sign of Extraterrestrial Signals. No sign.

One of the most important results of science is the negative result.  If something doesn’t work or a hypothesis is disproven, often it’s not widely reported or disseminated.  That is a shame.  However, science is getting better at incorporating negative results into its reporting system, which has resulted in publications like the Journal of Negative Results, which covers biomedicine.  

Unfortunately there isn’t a similar journal for Astronomy. At least not yet.  But the field could really use one.  There are plenty of disproven hypotheses that don’t see the light of day in academically peer reviewed publications.  When it comes to topics like SETI, sometimes those negative results are extremely important, as it lends credence to one of the most important hypotheses out there – that we are alone in the universe.  Papers that cover negative SETI results can be accepted into journals that otherwise might not accept a paper centered around not finding anything.  That’s what happened recently when a team of astronomers from Australia and elsewhere used the Murchison Widefield Array (MWA) to search a patch of sky that included 10 million stars.  The negative results was that they did not see a single sign of intelligent life anywhere in those 10 million stars.

The part of the sky the astronomers observed was around the constellation Vela, which takes up a relatively small portion of the southern sky.  They searched for 17 hours for radio emissions spectrally near commercially broadcast FM bands.  With all the resources of the MWA available, the astronomers were able to peer “more than 100 times broader and deeper than ever before” said l Dr. Chenoa Tremblay, one of the lead authors from Curtin University.

The Murchison Wide Field Array as used to survey the sky near the constellation Vela.
Credit: Curtin University

Even so, the area covered by the survey “was the equivalent of trying to find something in Earth’s oceans but only searching a volume of water equivalent to a large backyard swimming pool” continued Dr. Tremblay.  Obviously there is still a lot of space to cover in searching for any emissions.  

Image of antennas for the Square Kilometer Array being set up.
Some of the antennas being placed for the Square Kilometer Array.
Credit: ICRAR

The team hopes to continue and widen that search when the successor to the MWA comes online.  The Square Kilometer Array (SKA), which will eventually be the world’s largest telescope, will be built at the same location in Australia, and will also have a site in South Africa.  The hope is the SKA will be able to survey billions of star systems in the radio frequency.  It will also be 50 times more sensitive than the existing MWA array.   

Unfortunately, like so much in the research community, completion of the SKA has been pushed back to due COVID-19, with no clear launch date following its originally planned January 20201 start.  So Dr. Tremblay and her team will have a while longer to wait to be able to dive deeper into the SETI search.  On the bright side, the team was actually expecting the negative result they got from the first MWA survey.  Which means they are in fact able to report on a positively proved hypothesis anyway.

Learn More
ICRAR: Australian Telescope Finds No Signs of Alien Technology in 10 Million Star Systems
Publications of the Astronomical Society of Australia: A SETI Survey of the Vela Region using the Murchison Widefield Array
ScienceAlert: Across 10 Million Stars, Not a Single Whisper of Alien Technology
UT: Astronomers Are About to Detect the Light from the Very First Stars in the Universe

6 Replies to “Australian Telescope Just Scanned 10 million Stars For Any Sign of Extraterrestrial Signals. No sign.”

  1. ” When it comes to topics like SETI, sometimes those negative results are extremely important, as it lends credence to one of the most important hypotheses out there – that we are alone in the universe.” No, it doesn’t lead to that “most important” hypothesis at all. All it means is that there are no detectable radio signals in the frequency bands they are searching for. Do scientists really believe some intelligent species will be beaming radio signals at us or leaking them so that we can detect them and if there are none detected it means there are no other intelligent species out there? Really? That’s the conclusion?

    How about this: Radio communication is useless for communication over long distances and is not used by any other advanced species, other than us, at our current level of development. A more reasonable conclusion would be that in all the stars surveyed, there are no civilizations at exactly the same point in evolution as we are, that use exactly the same technology that we do. How about that? There could be many planets with civilizations less or more advanced than we are, that either don’t use similar technology if more advanced, or don’t have advanced technology at all yet. Why continue to jump to the “most important obvious” solution, that we are alone in the universe, unless that is the conclusion you want in the first place. Why not just conclude it and stop looking? Obviously it is the most obvious and important conclusion to a lot of scientists and religious fanatics. I’d put them in the same classroom, let them close their eyes and be happy with their imaginary universe. The rest of us can keep looking.

    1. Well you might instead say it only lends a bit of credence to the hypothesis. They’re trying to make seemingly reasonable assumptions and then observing. The fact that there’s absolutely nothing so far, means something, but it’s not at all clear just what, since we have basically zero knowledge yet about anything. So even your points about civilizations, their state, how they progress etc. is all complete speculation. There’s nothing to go on at this point so might as well just report what we see and don’t see but keep any further conclusions to a minimum – they’re not based on anything except mostly science fiction-derived personal bias. 🙂

      1. Beckler: I agree with your comments. My comments about possible intelligent civilizations are just speculation, and with nothing to go on I wouldn’t reach any conclusions either way. We could be alone, but I was just making the point about the “most obvious conclusion” comment. I just wouldn’t come to that conclusion with so little evidence. Those that automatically go there push my irritation button, but I shouldn’t let it. You’re response was more reasonable.

  2. (Really bad commenting system. I was replying to comment by Art14 but there’s no indication of that. I can’t edit comment, either. Garbage system – upgrade it please.)

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