With intelligent life in scant supply on Earth, boffins search for technosignatures of civilizations in the galaxy Astronomers are on the hunt for signs of alien civilizations in space by searching for things like extraterrestrial solar panels or planetary atmospheres spewing pollutants. The team, from the Harvard-Smithsonian Center for Astrophysics and the University of Rochester in the US, believe these so-called “technosignatures” are …
Intelligent life on a tidally locked planet? Easier to find arguments why it is unlikely. There is only a narrow stripe which could be arable land. The rest is either too hot and bright or too cold and dark. There are no tides. Hard to explain water circulation which does not disappear into either the too hot area or too cold area. Tidally locked makes it unlikely there are plate tectonics. This also means likely there is no or are very weak magnetic field. The solar wind would remove the atmosphere in this case.
Now it would be interesting to see how all of this could be overcome regardless...
The answer to that would depend on your own interpretation of varying Metaphysical concepts.
Socrates and Newton might have differing opinions.
Alternatively and away from philosophical viewpoints I would personally agree with the proposition that 42 is probably the answer.
In a probability somewhere, 42 is almost certainly the answer, although it's a million to one chance, nine times out of ten it will/ might happen.
As for intelligent alien life, PV panels are in their infancy here, anything reasonably well advanced or subject to development we haven't thought of yet and the reflective signature will be nothing like that expected from terrestrial PV.
The commonest pollutants that we produce are often similar to normal environmental pollutants such as methane, co2, sulphur dioxide etc and there is no guarantee another civilisation will necessarily develop along the same limes that we have, the thinking seems to be either simplistic or arrogant.
I'd say simplistic and naieve. There would only be a very short period of time for any society to be in the state that's looking for. Even our own EM emissions are drastically reduced now we have better broadcast technology but even if you rounded things up to 100 years of high powered directionless broadcasts, that's a very small window of time that another culture has to be within reasonable of range of these transmissions and to be looking for them. A 100 year sliding window in a galaxy that is already around 13.5 billion years old? Just not going to happen, or if it does, it's a phenomenal piece of luck. A culture looking for other cultures would have to monitor many thousands of systems for many thousands of years and would still have to be incredibly lucky. Human development within the time frame of vertebrate life on Earth is pretty much a rounding error.
Our search for life should involve better and better telescopes, of varying frequencies, to look for potential signs of life, as in chemically unstable anomolies where non-routine processes are affecting the balance of elements in a planet. The alternative is for some other culture to be deliberately broadcasting signals knowing that they would have to do this for tens of thousands of years and largely to never expect a reply, at all, let alone within any form of lifetime. The stronger these signals the better as the more power the more detectable range and therefore the more potential cultures could be looking.
there is no guarantee another civilisation will necessarily develop along the same limes that we have, the thinking seems to be either simplistic or arrogant.
Have you ever been able to observe Americans visiting a Furrin Coutry during a time where not every town was overrun with fastfood joints and other exponents of US 'culture' already? And gathering a statistically significant sample that way, noting the common behavioral elements?
Expecting everything to be the same everywhere is an utterly typical trait.
I think the idea is probably to look, first, at the plausible planets we can find which tend to be tidally-locked because they need to be in very tight orbits around very dim stars or we don't find them. Then when we get better at finding planets which really are earthlike we'll have the techniques sorted and we can look at them. This is like all the iterations of LIGO and its predecessors which no-one expected to hear anything: its technology & skill development.
IMO the Drake equation, whilst a useful list of things to consider, was never really an equation in any useful sense. And in the absence of known values for parameters, you have to take a different approach; e.g.
" The Great Silence - the Controversy Concerning Extraterrestrial Intelligent Life",
G. D. Brin,
Quarterly Journal of the Royal Astronomical Society 24, 283-309 (1983)
(you should be able to find a pdf online if you search)
Unlikely anyone's still reading this thread now, but this has a nice recent summary --
"Monte Carlo estimation of the probability of causal contacts between communicating civilisations"
Marcelo Lares, José Funes, Luciana Gramajo
In this work we address the problem of estimating the probabilities of causal contacts between civilisations in the Galaxy. We make no assumptions regarding the origin and evolution of intelligent life. We simply assume a network of causally connected nodes. These nodes ...
https://arxiv.org/abs/2007.03597
"... planetary atmospheres spewing pollutants" are "... evidence of intelligence in other places than Earth" ?? The phenomenon is evidence of lack of intelligence here on Earth.
Quite apart from which, why should the technologies of an alien planet be automatically similar to our own?
If we really believe that life will be similar to our on another world then we should be checking for facebook and twitter postings too. But maybe "life" could be like ours but very different, does anyone remember the intelligent alien locusts in the movie "Independence Day"? They had invented UNIX but that didn't make them like us ... or maybe, these days, it did?
We made the mistake of using Unix, SCO vs Mystronix has been going on for over 20 years now and they are still trying to get us to use our regenerative powers to make their money reappear.
Apparently replacing Kill with "WESHALLBEAVENGED" and ECHO with "THISISTHEVOICEOFTHEMYSTERONS" isnt enough
> why should the technologies of an alien planet be automatically similar to our own?
Indeed. We're way too narrow-minded. Looking for solar panels? Why not look for blockchain and IoT too? Do those aliens really need to check all the current buzzwords of human technology?
The environmental conditions of their planet are most likely to be different, meaning those aliens will be quite different from us, and have found completely different solutions to their completely different problems.
And even if this is a low-budget universe, and aliens are just regular humans with strange skin colors, living on a totally USA-like planet, why would they necessarily be exactly in our time frame of solar panels and mindless pollution? In human history it is but a short flash. Those aliens might be already mastering fusion, or they might have enough volcanic activity to be able to use geothermal power generation at large scale (for instance).
In short, those people are searching for humans, not for alien intelligent life...
Surely the thing to look for is (the original plan A) radio transmissions that are opbviously intelligently created? these will be beaming out from the planet , so more easily detected than measuring the amoutnof poluution , or the amount of fast food joints.
When we start recieving Alien Allie McBeal ...
Given the probable outcome of the only civilisation we know about, I wonder whether it might be more useful to look for the signatures of dead civilisations. Perhaps our civilisation might have been detectible by 1900, and if we assume it will be dead by 2200 at the latest then the chance of finding it alive are tiny.
So, for instance, how detectible and characteristic is the result of a nuclear way, say? It might be quite characteristic as there will be lots of decay products from weapons which might be quite distinct from the stuff dying stars spit out. Of course you need to look for long-lived things and they don't emit much, which is why they're long-lived.
Another approach I wondered about is: how bright are the flashes from nuclear weapons? Are they bright enough that you could see them from far enough to expand the search area for planets far enough to make it worth looking for them? Of course they'd also need to be distinct enough to be able to find them (does the double-flash thing from a nuclear weapon help?).
Problem is, nuclear wars don't last long so you will be looking for very short duration flashes.
Every way I look at it, I keep coming back to the relative numbers - long time, long distance, short lived civilizations etc. Even if we have one civilization per star we are looking at a signature of a vary small number of years relative to the life of the stars.
I'd love to see proof of intellligent (well any) life outside of our own particular paradise but I think I will be dead before we find it. We haven't even found it in our own back yard yet.
I really do hope we are not alone - the universe would be a complete failure if we were all/the best it had to offer :-)
I really do hope we are not alone
"Far out in the uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy lies a small unregarded yellow sun. Orbiting this at a distance of roughly ninety-two million miles is an utterly insignificant little blue green planet whose ape-descended life forms are so amazingly primitive that they still think digital watches are a pretty neat idea."
Yes, my idea was that if the flashes (or perhaps EMP effects?) from nuclear weapons are detectable over cosmologically large distances then you could watch a huge volume (number of candidates goes up as cube of distance of course). Same argument that makes increases in sensitivity of things like LIGO have such a dramatic effect in the number of events they see.
I think it's implausible though, I agree.
Nuclear weapons while very unpleasant and destructive are quite puny compared to the average tropical storm. I read somewhere that they kick out more energy over a relatively short period than the entire world's nuclear aresenal. I don't know accurate that is, but the energy in these and electrical storms in immense.
By way of surviving artifacts from a civilisation? They would be few and far between on Earth and eventually almost all would disappear through plate tectonics if nothing earlier and more immediate such as the actions of plants and wind/water/ice.
You are right about energy I think. But nuclear weapons release all that energy in a small fraction of a second so, for that small time, they are quite bright. That was my idea.
The more general idea of looking for detectable corpses of civilisations was just to try and make the window bigger. If (when probably: climate change leads to water and crop shortages leads to squabbles over them leads to escalation leads to nuclear war, say) we destroy ourselves with nuclear weapons in the next century then, perhaps, our civilisation might be detectable while alive for 150 years but the radiation signature of its end for perhaps a few thousand years. I'm making up the numbers though.
(And nuclear weapons are not that bright of course: which is brighter: a supernova seen from the distance of Earth's orbit or a hydrogen bomb pressed against your eyeball? The supernova ... by a factor of a billion (from xkcd).)
A nuclear detonation may be briefly bright, but not on an astronical scale and each one is a singular event. You'd have to be watching for the exact few minutes that there was the explosion and everything would have to be lined up with nothing inconvenient like moons, curvatures of the planet or stars in the way. Even then it would be pretty much indistinguisable from signal noise and depending on the reflectivity of the planet, would likely be less bright than light reflecting from the system's star.
We only know what to look for as far as technology we currently have, plus the effect of megastructures science fiction writers theorize that would be the signature of a civilization collecting a large portion of the power a star is generating.
If we did this 100 years ago, we wouldn't know to look for satellites and solar panels. We'd probably look for lots of smog from all the coal burning they'd be doing. If we ever get fusion working efficiently and cheaply, maybe solar panels no longer have much of a role and they won't be seen on Earth 100 years from now. So how do we know what to look for in a civilization a mere 100 years ahead of us?
How about one 1000 years, or 100,000 years more advanced than us? Maybe some new sort of quantum communication someday makes communication satellites obsolete. Maybe they have some sort of 'stealth' technology that eliminates the artificial signatures being detectable from the outside, because they have a Frank Lloyd Wright sense of aesthetic and want to look natural when observed from their planet's moon, or because they don't want to advertise their existence to potentially more aggressive neighbors. It would be a lot easier as a civilization that's been around a million years to know what to look for than one that's only a few thousand years down that road.
Not saying we shouldn't look, but I certainly wouldn't take a lack of evidence of aliens as evidence of a lack of aliens.
The most compelling evidence for life, and therefore life elsewhere (aliens), is that there's life on this planet.
As for finding life elsewhere? That's a very different prospect indeed. It's probably made even harder because there's a very good chance that conditions for life on any given planet will become hostile for life and it'll all die out and therefore be missed. Whether this is caused internally through runaway processes or through external natural disasters, life may be very resilient but it's far from impossible for a planet to no longer be habitable.
It's searching under lampposts. There are only some things we can look for: if we don't look at all we have a chance of zero of finding something, if we look where we can look we have a chance which is not less than zero and may be greater. And by looking we get to to technology development on the machines we use for looking so related machines can look for other things, like vegetation with more sensitivity.
It seems curious to me that our best minds are desperately trying to detect our level of technology on other planets.
That wavelength is where you would see sunlight reflected off of our solar panels. What right do you have to decide that an alien civilization is using the same solar panel tech ? They might have room-temperature superconducting solar panels that don't reflect anything at all and are 100% efficient.
You won't detect that.
We know that the solar panels we make depend on physics and we have good evidence that the laws of physics don't change in the volumes of space we're searching (and much greater volumes than that in fact).
So we know aliens could make solar panels using the same physics we do. And we know how to look for those. We don't know how they might make other kinds of solar panels, still less how to look for their signature. So we look for the things we may be able to detect and which we know could exist, not for the things that we do not know can exist and do not know how to detect. That's not a stupid approach. It may not (almost certainly will not) find anything, but the alternative certainly has a chance of zero of finding anything.
The real reason we don't hear from alien life forms is because we are in the shit universe. My theory is, there is some technology, which we haven't discovered, but is not far from our level of development that will allow life to leave this (shit) universe and simply go somewhere better. So the reason we dont have any signals from aliens is because they have simply buggered off.
Its now time for me to have my medication and rest for a bit.!!!
The two sides can exchange ideas on the basic building blocks of the universal language of porn, and how to detect that in incoming radio traffic from the cosmos.
For example, the aliens must have plumbers too, right? So how do we need to find out how to detect which incoming signals show them arriving in an unrealistically short time after being called, and only when one scantily clad female, or maybe her and her adventurous best friend, are at home.
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