# Another "Wow!" Signal?



## mosaix (Aug 30, 2016)

Alien life, or noise? Russian telescope detects 'strong signal' from sun-like star

_Signal detected a year ago from HD164595, only 95 light years away and with at least one planet, but Seti scientists are scanning the area and have yet to find it_

_A Russian radio telescope scanning the skies has observed “a strong signal” from a nearby star, HD164595, in the constellation Hercules. The star is a scant 95 light years away and 99% of the size of Earth’s own sun. It has at least one planet, HD164595b, which is about the size of Neptune and has a 40-day year.
_
We can but hope...


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## Venusian Broon (Aug 30, 2016)

mosaix said:


> Alien life, or noise? Russian telescope detects 'strong signal' from sun-like star
> 
> _Signal detected a year ago from HD164595, only 95 light years away and with at least one planet, but Seti scientists are scanning the area and have yet to find it_
> 
> ...



Disappointingly, from the article, it seems that even SETI was a bit dubious/sceptical about this piece of news


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## Old_Man_Steve2016 (Aug 30, 2016)

If there is radio-active life (Not radioactive life) in that solar system, we should be able to detect more than one signal over the course of time. If we don't, then other sources are likely the cause.


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## Vertigo (Aug 30, 2016)

Once again the point should be made that if there is a civilisation at that location and they are transmitting omnidirectionally (rather than beam a signal directly at us as opposed to anywhere else in the universe) it is extremely unlikely we would be able to detect such signals over a distance of 95 light years. Unless they are transmitting at levels approaching stellar in power... Or, who knows, maybe we just witnessed the tail end of a terminal nuclear war.

Sorry to be such a pessimist but there's no easy way to get around the inverse square law.


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## zmunkz (Sep 1, 2016)

What @Vertigo said.

And the likelihood of pointing directly at us is miniscule. Our own use of radio has transitioned away from high-powered omni-directional and towards lower-powered directed-at-satellites, which in turn broadcast downward.

In other words, the window of years during which we had any significant radio signature is brief, presenting a major challenge to potential aliens to detect us from the background before our transmissions went  mostly quiet.


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## Vertigo (Sep 1, 2016)

zmunkz said:


> What @Vertigo said.
> 
> And the likelihood of pointing directly at us is miniscule. Our own use of radio has transitioned away from high-powered omni-directional and towards lower-powered directed-at-satellites, which in turn broadcast downward.
> 
> In other words, the window of years during which we had any significant radio signature is brief, presenting a major challenge to potential aliens to detect us from the background before our transmissions went  mostly quiet.


...and even when we were transmitting in that way the power levels in interstellar terms were miniscule.

As has been discussed before I just can't see any way that this is a sensible method of detecting extra terrestrial life. It makes no sense to me, and is also, given the ftl limitations on interstellar travel, why I don't consider the Fermi paradox to be any kind of paradox.


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## Ensign Shah (Sep 1, 2016)




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## Vertigo (Sep 1, 2016)

So do I  but not based on false hope...


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## Dave (Sep 1, 2016)

Vertigo said:


> Sorry to be such a pessimist but there's no easy way to get around the inverse square law.


A question: They already improve the power of radio telescopes by connecting them together across the Earth in a net. Would it be possible to have radio receivers placed in orbit around the outer planets and to connect those together in a net to achieve a similar effect? I'm asking because I don't know. Maybe the frequencies involved mean that the power is still much too low. I know the radio telescopes are looking at high-end radio frequencies - x-rays and gamma - and that television and radio broadcasts are much less powerful. Is radio in that wavelength/frequency so unusual to be naturally produced that even the smallest amount is significant?

In any case, I agree with the other points made about the "window" of technological progress, which means that this is all probably a waste of effort and time anyway. 

How else can we look for evidence of other civilizations though?


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## Venusian Broon (Sep 1, 2016)

Dave said:


> A question: They already improve the power of radio telescopes by connecting them together across the Earth in a net. Would it be possible to have radio receivers placed in orbit around the outer planets and to connect those together in a net to achieve a similar effect? I'm asking because I don't know. Maybe the frequencies involved mean that the power is still much too low. I know the radio telescopes are looking at high-end radio frequencies - x-rays and gamma - and that television and radio broadcasts are much less powerful. Is radio in that wavelength/frequency so unusual to be naturally produced that even the smallest amount is significant?
> 
> In any case, I agree with the other points made about the "window" of technological progress, which means that this is all probably a waste of effort and time anyway.
> 
> How else can we look for evidence of other civilizations though?



Just off the top of my head (so ready to be corrected...)

Yes, connecting together observatories (of all sorts) works. Technically getting observatories to either side of the solar system, however, is a little bit beyond us at the moment (not impossible, just likely to be extortionate in terms of cost and likely to remain so for a long while IMO). The reason not a lot of radio telescopes work in the long infra-red is that the Earth's atmosphere absorbs a great deal (and we have polluted our local area with lots of crap TV and radio!) Infra-red in space is different - I believe there are a few observatories in orbit that work in that part of the spectrum now. 

Radio and TV transmissions are beyond the infra-red,meaning long wavelength EM. Unfortunately I believe there are a great number of natural sources of such radiation - star produce them constantly anyway, planets interacting with solar winds etc... Remember that in the old days, that fuzzy de-tuned TV screen (William Gibson 'The sky above the port was the color of television, tuned to a dead channel')...approximately 3% of that actual signal was caused by the big band background radiation. 

Thus for an alien civilisation (or us) to produce a signal that could be significant above this natural background of many sources, and also able to be picked up far away (see Vertigo above!) would require, erm... an astronomical amount of energy. And that's not even talking about it being broadcast or specifically aimed at certain star systems. To make it broadcast everywhere around it...astronomical squared???

As for looking for evidence for other civilisations...

Our best bet is the premise of the Fermi paradox. We humans are ill-suited for interstellar travel - at least with the tech we have - however we can possible imagine that in the long-term future we could see fleets of self-replicating machines, able to fix themselves that could slowly reach out and explore the universe, picking up new material where they find it to make copies and sending them further and further out. At some point they might well find other civilisations and then send back word to who or whatever is living on Earth at that time. Even with sub-FTL travel I believe such an approach could map out the galaxy relatively quickly (millions of years not billions)...but this raises the question, if this is the case where are the alien self-replicating machines?


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## Gawian (Sep 1, 2016)

Let's be honest, if there are intelligent civilisations out there (dear gods, say there are), then they should be intelligent enough to avoid this noisy disgusting little planet.


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## SilentRoamer (Sep 1, 2016)

Hey Dave,

The inverse square law Vertigo mentioned up thread pretty much seals the deal in terms of radio detections.

You can detect the radio wavelength at very long wavelengths but you would need a huge radio antennae to do so.

My personal opinion is that the most likely detection method for a sufficiently advanced alien civilization would be the monitoring of stellar luminosity or "transit" detection. The reason I say this is that any sufficiently advanced civilization is likely* to have much deeper energy dependency requirements will eventually result in a higher Kardashev scaling and require almost the entire output of the parent star. Think Peter Hamiltons Pandoras Star. Or perhaps looking for unexpected star creation in stellar nurseries.

I think if we are looking for human level scale of technology we will never find it.

The sort of timescales and distances involved just preclude any sort of reasonable communication - personally I don't subscribe to the propositional mathematics of the Fermi Paradox - they place far too much stock in the Drake equations which are essentially just guesswork. Working from a sample of one we have created the equations for likelihood of life - yeah right!

For the record, I absolutely believe in intelligent and alien civilized life, it may even be possible (probably probable given scale function) that somewhere in the Universe there are species that have actually met (imagine two planets habitable to life at the same time orbiting the same star) but on the whole the Universe is so physically big and cosmological timescales so temporally long that billions of species will live and die on their planet/nebulae/moon of origin unaware of the multitude of lifer in the Galaxy.

Just my ramblings and musings.


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## Vertigo (Sep 1, 2016)

Dave said:


> A question: They already improve the power of radio telescopes by connecting them together across the Earth in a net. Would it be possible to have radio receivers placed in orbit around the outer planets and to connect those together in a net to achieve a similar effect? I'm asking because I don't know. Maybe the frequencies involved mean that the power is still much too low. I know the radio telescopes are looking at high-end radio frequencies - x-rays and gamma - and that television and radio broadcasts are much less powerful. Is radio in that wavelength/frequency so unusual to be naturally produced that even the smallest amount is significant?
> 
> In any case, I agree with the other points made about the "window" of technological progress, which means that this is all probably a waste of effort and time anyway.
> 
> How else can we look for evidence of other civilizations though?


@Venusian Broon has done most of the answering and I agree with all he says (including the ready to be corrected bit)

On your last question our best bet for the future (and we are pretty much there now in fact just a question of scale) is to detect exo-planets and analyse their atmosphere. Should be easy enough if the planets' orbits pass across our line of site to their stars not so easy if they don't. It is thought that any technological civilisation would produce chemicals in their atmosphere that we could detect using spectroscopy. Wouldn't work quite so well with an intelligent civilisation that doesn't produce technology waste and lives in perfect harmony with their biosphere but then they wouldn't exactly be beaming out radio waves either.

So the short answer is spectroscopic analysis of exoplanet atmosphere's which, as I say, we can do today: ESA Science & Technology: Exoplanet Spectroscopy Mission (ESM)

Edit: @SilentRoamer got in whilst I was typing - but I also agree with all he says


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## Venusian Broon (Sep 1, 2016)

SilentRoamer said:


> The sort of timescales and distances involved just preclude any sort of reasonable communication - personally I don't subscribe to the propositional mathematics of the Fermi Paradox - they place far too much stock in the Drake equations which are essentially just guesswork. Working from a sample of one we have created the equations for likelihood of life - yeah right!



Fermi paradox and Drake equation are not connected whatsoever i.e. Fermi paradox does not use it at all. But you are correct that the Drake equation is just a coffee table discussion, not an actual equation that gives you any answer. It just gives you any answer _you_ want.

Actually, Fermi paradox assumes most of what you wrote afterwards as your beliefs . With the proviso that there is a sufficiently advanced civilisation that would be willing to start the whole shabang.


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## Venusian Broon (Sep 1, 2016)

Vertigo said:


> On your last question our best bet for the future (and we are pretty much there now in fact just a question of scale) is to detect exo-planets and analyse their atmosphere. Should be easy enough if the planets' orbits pass across our line of site to their stars not so easy if they don't. It is thought that any technological civilisation would produce chemicals in their atmosphere that we could detect using spectroscopy. Wouldn't work quite so well with an intelligent civilisation that doesn't produce technology waste and lives in perfect harmony with their biosphere but then they wouldn't exactly be beaming out radio waves either.
> 
> So the short answer is spectroscopic analysis of exoplanet atmosphere's which, as I say, we can do today: ESA Science & Technology: Exoplanet Spectroscopy Mission (ESM)



The only problem with such an approach is that it would be easy to generate false positives - we could look at an atmosphere of an Earth-like world hundreds of light years away and discover it filled with Oxygen and methane or filled with 'pollutants' that we deem to be 'artificial'. Thus we might get excited and - 'There's life there, Jim! Surely!!' 

The only sure way would be to actually travel there and check it out, otherwise we could never say as we could discover (likely as we have seen _so _little of the universe) that there is a perfectly reasonable natural solution to the observations that do not involve any form of life whatsoever. 

It would certainly help pick out nice sites to go and visit, if we ever get interstellar travel up and running...


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## Vertigo (Sep 1, 2016)

Venusian Broon said:


> The only problem with such an approach is that it would be easy to generate false positives - we could look at an atmosphere of an Earth-like world hundreds of light years away and discover it filled with Oxygen and methane or filled with 'pollutants' that we deem to be 'artificial'. Thus we might get excited and - 'There's life there, Jim! Surely!!'
> 
> The only sure way would be to actually travel there and check it out, otherwise we could never say as we could discover (likely as we have seen _so _little of the universe) that there is a perfectly reasonable natural solution to the observations that do not involve any form of life whatsoever.
> 
> It would certainly help pick out nice sites to go and visit, if we ever get interstellar travel up and running...


I agree absolutely and that's why my first question about that recent nearby 'Earth-like' exoplanet was whether it transits our view of its star.... I've still not found an answer to that question. As I understand it it was discovered by detecting the star's wobble but I'd love to know what the plane of it's orbit is. I suspect it doesn't transit otherwise they probably would have 'confirmed' the discovery by detecting the dip in light output during the transits. But maybe we have to wait a while for it to come around...

But you are correct; ultimately the only real way of determining for certain is to visit 

Edit: it occurs to me I didn't express myself very well there. I meant I agree absolutely that it only really tells us that a planet might be an interesting possibility which is why I wanted to know if that nearby earth-like planet might be such a potentially interesting place.


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## SilentRoamer (Sep 1, 2016)

Venusian Broon said:


> Fermi paradox and Drake equation are not connected whatsoever i.e. Fermi paradox does not use it at all.



Should probably have made myself clearer.

The contradictions inherent in the Fermi Paradox are only made into contradictions when using the Drake equations or a similar probabilistic scale as one side of the "paradox": namely the high probability rate. Without the Drake equations (or an equivalent high probability scenario) then there would be no paradox to resolve.



Venusian Broon said:


> Actually, Fermi paradox assumes most of what you wrote afterwards as your beliefs . With the proviso that there is a sufficiently advanced civilisation that would be willing to start the whole shabang.



It assumes them as hypothetical solutions to the supposed Paradox yes. Worth mentioning though that one of the suppositions is also that complex life or even technologically advanced complex life is just extremely rare - even a single event.

Really Venusian - we talked over beer and never brought up the Drake equations or the non paradoxical nature of the Fermi paradox, shame on us!


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## Venusian Broon (Sep 1, 2016)

@Vertigo 

I remember years ago, a team (inc. Carl Sagan I believe) used the fly-by* of the Galileo spacecraft to its instruments. Part of that test was to see if they could pick up any signs of civilisation and intelligent life on Earth, i.e. could be used in more long range studies, such as the ones you are talking about. 

Unfortunately apart from detecting the obligatory oxygen, methane and other quite transient short-lived gases in the atmosphere, there was little evidence produced of any life whatsoever. And remember, this is a near Earth flyby! Part of the reason for the inconclusive findings was that the probe only flew by Antarctica and Australia - both mostly deserts. If it had been over the Amazon, Central Africa or tropical Asia then they might have got better results...

(Got a big laugh when I presented the paper for our 'lunchtime scientific paper club' - stating that it couldn't find any signs of intelligent life over Oz )





-----------------------------
* (they used gravitational assists of Venus then back to the Earth to get it into a nice Jupiter orbit)


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## Venusian Broon (Sep 1, 2016)

SilentRoamer said:


> Really Venusian - we talked over beer and never brought up the Drake equations or the non paradoxical nature of the Fermi paradox, shame on us!



I know, we should aim soon to rectify that. 

But the thing about the Drake equation is that I can easily 'use it' to give the answer that there are* zero* other civilisations in the entire universe - it is not necessarily something that returns the answer there is a high probability of technological advancement and aliens in space. It can if you want to, but as you pointed out, it's virtually unknowable for some of the variables that it uses.  

One must, unless you wish (IMO) to fall into illusions of grandeur, use the Copernican principle - one of the unstated assumptions of the Fermi paradox. We are not special and neither is our situation. 

This is to my mind the 'paradox' sitting at the heart of this, if there are no self-replicating spacecraft à la black monoliths then perhaps, the 'sensible' Copernican principle is not true and therefore we are indeed unique and alone in the cosmos. Something I feel clashes with our growing understanding of the universe. (I can't prove that, but I hope we get substantial evidence in the coming century, say - evidence of life on Mars that evolved independently of life on Earth)

Of course there are a hundred and one other reasons why the Fermi Paradox might hold right now. Several of which form the basis of some of my fictional universes, so if I ever get round to writing about them...


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## Vertigo (Sep 1, 2016)

I'm a bit twitchy about the self-replicating spacecraft idea. My problem is that trundling around the galaxy like that over those sort of timescales and merrily replicating as they go, errors are going to creep in through radiation damage with no sentient intelligence to keep a monitor them. Okay so maybe I've read too many SF scare stories along those lines, but I do wonder whether sending stuff like that out into the galaxy would be a very responsible activity for an advanced technological civilisation to be partaking in.


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## Venusian Broon (Sep 1, 2016)

Vertigo said:


> Okay so maybe I've read too many SF scare stories along those lines, but I do wonder whether sending stuff like that out into the galaxy would be a very responsible activity for an advanced technological civilisation to be partaking in.



I'd say you probably read too much SF...but er, most of us have here anyway .

Anyway we're supposedly sentient and we f*ck up most of the time - if these machines are not allowed to travel between the stars then I'd argue that biological life - merrily replicating, flooded with DNA errors creeping in through radiation damage with no intelligence on what to do would act equally as badly.


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## BAYLOR (Sep 4, 2016)

Venusian Broon said:


> I'd say you probably read too much SF...but er, most of us have here anyway .
> 
> Anyway we're supposedly sentient and we f*ck up most of the time - if these machines are not allowed to travel between the stars then I'd argue that biological life - merrily replicating, flooded with DNA errors creeping in through radiation damage with no intelligence on what to do would act equally as badly.



For some reason, this  topic makes  think of the novel *The Killing Star* by Charles Pellegrino  and George Zebrowski.


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