Advanced alien civilizations rare or absent in the local universe

September 16, 2015, Netherlands Institute for Radio Astronomy
The figureshows what the activities of a Kardashev Type III civilization might look like — encapsulating the energy of stars by so called Dyson spheres or swarms is one way to harness enormous energies on truly galactic scales. The resulting waste heat products such a galactic scale enterprise would produce, should be detectable by today’s telescopes. Credit: Danielle Futselaar/ASTRON

Sensitive new telescopes now permit astronomers to detect the waste heat that is expected to be a signature of advanced alien civilizations that can harness enormous energies on the scale of the stellar output of their own galaxy. Professor Michael Garrett (ASTRON General & Scientific Director) has used radio observations of candidate galaxies to show that such advanced civilizations are very rare or entirely absent from the local universe.

Advanced civilizations harnessing energies on galactic scales (so-called Kardashev Type III civilizations) are expected to be detectable in the mid-Infrared part of the spectrum via the emission of significant waste heat products. A team of led by Dr. Jason Wright (Penn State University, USA) has already drawn up a list of several hundred candidate galaxies (culled from a total population of 100,000 objects) where unusually extreme mid-IR emission is observed. One problem is that although rare, this kind of emission can also be generated by natural astrophysical processes related to thermal emission from warm dust.

Professor Michael Garrett (ASTRON & University of Leiden) has used radio measurements of the very best candidate galaxies and discovered that the vast majority of these systems present emission that is best explained by natural astrophysical processes. In particular, the galaxies as a sample, follow a well-known global relation that holds for almost all galaxies—the so-called "mid-infrared radio correlation." The presence of radio emission at the levels expected from the correlation, suggests that the mid-IR emission is not heat from alien factories but more likely emission from dust—for example, dust generated and heated by regions of massive star formation.

As Professor Garrett explains: "The original research at Penn State has already told us that such systems are very rare, but the new analysis suggests that this is probably an understatement, and that advanced Kardashev Type III civilizations basically don't exist in the local universe. In my view, it means we can all sleep safely in our beds tonight—an alien invasion doesn't seem at all likely!"

Joking aside, Professor Garrett is still looking at a few candidate that lie off of the astrophysical correlation: "Some of these systems definitely demand further investigation, but those already studied in detail turn out to have a natural astrophysical explanation too. It's very likely that the remaining systems also fall into this category, but of course it's worth checking just in case!"

The technique applied by Professor Garrett can also be used to help identify less advanced (Kardashev Type II) that command more limited resources on sub-galactic scales. Such civilizations are still considerably more advanced than our own (Earth is not yet on the Kardashev Type I scale) but they might be more common as a result.

Professor Garrett has plans to look for these less advanced civilizations: "It's a bit worrying that Type III civilizations don't seem to exist. It's not what we would predict from the physical laws that explain so well the rest of the physical universe. We're missing an important part of the jigsaw puzzle here. Perhaps advanced civilizations are so energy efficient that they produce very low products—our current understanding of physics makes that a difficult thing to do. What's important is to keep on searching for the signatures of extraterrestrial intelligence until we fully understand just what is going on."

The main results are presented this week as a letter in the European journal Astronomy & Astrophysics.

Explore further: Search for advanced civilizations beyond Earth finds nothing obvious in 100,000 galaxies

More information: Astronomy and Astrophysics 2015, A&A, 581, L5 "Application of the Mid-IR/Radio correlation to the Ĝ sample and the search of advanced civilisations" - M.A. Garrett DOI: 10.1051/0004-6361/201526687 and

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5 / 5 (8) Sep 16, 2015
These civilisations would need to be advanced and have existed at exactly the right time for the light to reach us now. Maybe also there is some kind of undiscovered advanced technology that the Kardeshev scale does not allow for. Technology which would allow for ultra efficient manufacturing and transport compared to our current standards for instance.
4.2 / 5 (9) Sep 16, 2015
The elephant in the room is the weakness in Kardashev's steampunk assumption that a civilisation more advanced than ours would still be dependent upon classical thermodynamics, only moreso.

Almost by definition, a successful intergalactic civilisation will be using the vacuum as source and sink, if not also for propulsion and communications, so we'd need to find a way of remotely sensing vacuum entropy changes signifying asymmetric energy interactions with the fundamental forces applied as sources and non-dissipative sinks.
1.4 / 5 (5) Sep 16, 2015
A rough example of such an interaction: from the surfaces of two bodies in elongate orbit, close passes cause surface gravity attenuations. IOW the force is varying, for free. Therefore, from either surface, lift a mass when it's lighter, drop it when it's heavier and you've "created" energy. Or destroyed some if you did it backwards. This has no effect on their orbital dynamics, it's effectively "non-thermodynamic" energy in the classical sense.

This example's still too steampunk, but simply illustrates that asymmetric force interactions are feasible in principle - there's a source and sink there, so technologies will develop to optimise its usage, albeit more likely EM and nuclear than gravitational..

Such gradients must still have associated entropy changes, so what are they and how to look for them? What happens to the vacuum when we force it to perform more output work than the input work it recivies back, by exploiting passive field density fluctuations?
4.2 / 5 (11) Sep 16, 2015
I doubt advanced civilizations build galaxy networks...there is not a need for huge structures or huge populations.

Advanced civilizations are probably small and quiet.

Their methods for categorizing progress are woefully connected to our concepts of "empire"

Greed isn't necessary for progress
1 / 5 (1) Sep 16, 2015
Perhaps civilisations need to be in equivalent of our 'Local Bubble' ??
4 / 5 (6) Sep 16, 2015
"heat from alien factories"
articles like this really make me chuckle :)
1.4 / 5 (8) Sep 17, 2015
Until some actual evidence of even the most primitive of life (that has not emanated from Earth) is found anywhere in our solar system, much less anywhere outside of our solar system, then talk of 'advanced civilisations' is slightly whacky.

In fact it would be a major breakthrough if we actually were able to work out how life really began on Earth. Which we do not really have the foggiest notion.
2.3 / 5 (7) Sep 17, 2015
I prefer to side with Kaku, in that aliens in spacecraft (UFO's) don't routinely bring themselves into the lab for observation. And...I get the feeling that they don't like radio...or just don't like generating such waves. Garret's work seems dreamy and not worthwhile. A different science direction is can only stare into space with radio waves for so long. Question: Does human advancement simply mean technological advance? Are there other types of advancement? Most scientists fail here due to their involvement as technocrats. My background?: performance on the largest mainframes...but I don't think tech-advance is what it is purported to be. Many times the tech-mind cannot grasp simplicity...yet Occam's view remains...
3.3 / 5 (4) Sep 17, 2015
If Black Holes can be used for hypercomputation that is where the advanced civilisation will congregate
2.6 / 5 (8) Sep 17, 2015
Don't tell the "History Channel"!!
2.8 / 5 (5) Sep 17, 2015
Lost in the wilderness, we are searching for someone's campfire.
3.1 / 5 (9) Sep 17, 2015
A machine singularity is not a 'civilization'. It is the inevitable result of a technology-based civilization.

Machine singularities will not need to consume any more energy or resources than they need to ensure their long term survival. Indeed, minimizing consumption would be a survival strategy.

And they would have no need to converse with pre-singularity civilizations. They might consider on site monitoring of these civilizations but could do so surreptitiously with machine remotes located nearby where we would never find them.
3.6 / 5 (7) Sep 17, 2015
Note I am a lay person...

I find it puzzling that it has only been in the last decade or two that we can detect the effects of alien planets on parent stars. More recent we can get a sniff of their atmospheric composition. So now we have made that leap to being able to decipher that a planet is emitting excess heat? Not just in our own Milky Way but in distant galaxies! I guess I am more impressed with this leap in our sensor abilities than the findings noted in this article. But I would have thought pinpointing a planetary system in another galaxy is impressive enough, but noting that one candle amidst a bonfire of stars is slightly hotter than what we predict it to be is very surprising.

Don't jump on me if I am misreading this. Was just my first impression as dummy interested in all things astronomy :)
2.1 / 5 (9) Sep 17, 2015
'Bonfire of stars' ahaahaaaa

We have been examining stars via spectral analysis for centuries now. Detecting IR as waste heat at certain frequencies expected from technological civilizations is easy.
Don't tell the "History Channel"!!
Hey say something else vapid and shallow and worthless.

I dare ya.
2 / 5 (2) Sep 17, 2015
@TopherTO: The type 3 civ is one that harnesses the power of an entire galaxy. So it was only galaxy measurements and not planet measurements in this study.

However, I believe that they are already able to detect the temperatures of the larger exoplanets, but it should be a matter of time before we can do it to terrestrial sized ones!
1.3 / 5 (10) Sep 17, 2015
According to Snobby Universe Theory the universe is like high school with cliques that have little communication with each other and exist in separate social circles excluding undesirables. As adults humans try to live in exclusive gated communities, send their children to exclusive schools and try to get past the doorman into exclusive clubs. The technological difficulty of space travel is the fence blocking human migration into the universe where they would be mingling with alien elites who want them excluded from the club. Humans are trying to tunnel under or scale the fence of technology excluding them from an elite alien society. Alien agents (called moderators) are on earth working to repair the technological fence preventing humans from migrating where they are not wanted. They maintain the fence by sabotaging human science. Alien moderators are supporting global warming political science to destroy scientific integrity. Humanism is the racism of alien civilization.
3.4 / 5 (9) Sep 18, 2015
According to Snobby Universe Theory the universe is like high school with cliques that have little communication with each other and exist in separate social circles excluding undesirables
Why dont you just go and have a nice conversation with the chipmunks in your backyard? Im sure they are expecting it, and you might find it enlightening.
2.4 / 5 (5) Sep 19, 2015
The Universe has a built in safety mechanism to keep all the developing civilizations discovering each other. There could be all kinds of technical societies right this moment in the Andromeda Galaxy and we would not become aware of them for 200 million or so years. The astronomical distances between life supporting planets effectively keeps us all in the dark . Another reason I suspect we haven't heard any radio traffic is I believe radio waves will be found to cause ill effects in humans.At some point in the future we will abandon radio for a more efficient form of communication. We live our entire lives bathed in all sorts of man made radio fields. Advanced civilizations probably communicate with technologies we haven't even dreamed of yet.
3 / 5 (1) Sep 19, 2015
Dirk you nailed it, but more for their own discoveries, I don't get the hypercomputing, in the end it's probably just for the view.
2 / 5 (3) Sep 19, 2015
Or we could be the very first species to be born into the Universe.....? After all, we hardly know the whole chronology of everything, everywhere.
3.7 / 5 (3) Sep 19, 2015
I applaud the search of ETIs simply because it can, and does, find all kinds of interesting features and phenomenon. On the other hand, I have little faith that they will eventually find advanced intelligent life for many reasons. Among them, why do they even think that they'd would just be using scaled up versions of our technology? Their communication may be something more advanced and incomprehensible to our radio usage as radio is to a neolithic culture that uses smoke signals. As to IR radiation, that's just part of the EM spectrum, and raw energy. For as far as we know, they either insulate against that, don't produce near as much as we assume, or even that they harvest and recycle it since it is energy.
On top of all that, even though megastructures like a Dyson Sphere make interesting sci-fi, it's very possible that by the time a civilization can make something like that, they may have no desire to, or more probably, already have a better solution.
Thanks for reading :)
4 / 5 (2) Sep 19, 2015
The universe is ALL MINE! you will never lay a finger on it!
No need to have a bunch of wild animals running all over the place.
Even if there was any aliens out there, why would they go looking for trouble?
3 / 5 (1) Sep 20, 2015
If there are aliens they would be waiting near blackhole (slower time) to pass knowledge to us when it's time for their species to move on.. Visiting every thousand years..
2.5 / 5 (2) Sep 20, 2015
no we are definitely not the first, there must be highly highly evolved beings in all these galaxies.
2.5 / 5 (2) Sep 20, 2015
Why would a people waste so much energy that they would raise the temperature of an entire galaxy? How would heat travel so far so fast? Every galaxy probably hosts tens of thousands to hundreds of thousands of space faring cultures, and millions of lesser cultures if not billions. Our technology cannot even resolve a crater or a moonlet of the PLANET Pluto, so what gives anyone the chutzpah to make asserverations about galaxies much less the universe.
Sep 20, 2015
This comment has been removed by a moderator.
3 / 5 (1) Sep 20, 2015
The proof that there must exist extraterrestrial intelligent life is the fact that nobody has ever contacted us from the outer space.
1 / 5 (1) Sep 21, 2015
Perhaps intelligence doesn't give a long term survival advantage. Eventually all civilizations destroy themselves long before they are anywhere near Type III.
2.5 / 5 (2) Sep 21, 2015
Advanced civilizations harnessing energies on galactic scales (so-called Kardashev Type III civilizations) are expected to be detectable in the mid-Infrared part of the spectrum

As he notes in the last paragraph: The problem with this argument (as with the SETI radio emissions) is - it supposes that advanced K-type civilizations never start to optimize their energy consumption/waste problem. That is an argument that is already starting to be wrong for humans - why would we assume that it holds for galactic civilizations?

In addition: IF waste heate were unavoidable - don't we think THEY know this (i.e. would they not manage their waste heat so as to not be noticeable - e.g. by directing it at stars or radiating waste away in another form of energy (gravity waves?).

It doesn't pay to advertise in a huge universe.

(Additionally I can't really think of anything that would require galaxy scale energy output, but that's not really a counter-argument)
3 / 5 (1) Sep 21, 2015
So, everyone thought of the thermodynamics assumption, the rest is just trolls. I doubt they'd go out of their way to announce themselves. If a civ were that advanced, why would it want to know the likes of us? You can appreciate Neanderthals as bright, advanced creatures, but would you want a family camped out next to your house, killing whatever strikes their fancy, using brute force in social relations and defecating in the stream out back?

The real hubris in the article is in taking a situation that is threatening to end our civ and assuming that it would be highly indicative of others. Hey, maybe deciding to use the thin little atmospheric blanket as a toilette isn't a common error. Maybe greed isn't the prime motivator. Maybe individuals can follow facts over ego identity. Maybe they cull the idiots in their population. Maybe they aren't vermin.
2 / 5 (1) Sep 21, 2015
I don't know about Kardashev alien civilizations, but it sure seems like someone has been hitting the Kickapoo joy juice again.
1 / 5 (1) Sep 21, 2015
Tastes Great! Less Filling!
5 / 5 (1) Sep 21, 2015
Hilarious! As the Milky way is 100,000 light years in diameter, it would take that much time for another civilization's emissions to reach us and vice versa, from end to end, that is. How far away are these other galaxies? Say, isn't our closest galactic neighbor 2.5 Million years away?
What was our TV or heat emissions like 2.5 million years ago?
Obviously, those living in Andromeda must make the same assumption. But only if they follow the same silly line of 'reasoning'.
not rated yet Sep 22, 2015
What was our TV or heat emissions like 2.5 million years ago?

2.5 million years ago isn't much of a time compared to the age of the universe. And IF a civilization spreads* to its entire galaxy then it could well have done so in other galaxies several billion years ago.

*Something I find pretty implausible, BTW. Like the Kardashev classification it posits that civilizations advance immeasurably in some areas (huge megastructures, galaxy-wide spread) while remaining totally dumb/more static than humans currently are in others (i.e. no advance at all in power use/efficiency as well as no longevity/virtualisation/group mind/bodily modification to live in space/etc - any of which would make a galaxy-wide spread pointless).

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