Is the SETI Search for Extraterrestrials Doomed to Fail?

[flexy]

We're scanning the skies with SETI on various radio frequencies, not because it's an effective means to find an extraterrestrial civilization, but it's the ONLY means we currently have.

There was some hype the recent days again because SETI found a POSSIBLE signal https://forums.anandtech.com/thread...resting-signal-from-star-in-hercules.2485041/
but of course the usual caveats apply. And one of the biggest caveats and reason to criticize then entire SETI search effort...would be: WHAT ARE THE ODDS?

And those odds are, admittedly, extremely, extremely small.

Let's take a random planet which, like ours, had billions of years to develop life.

The problem is the idea of receiving a signal from a civilization on such a planet "at exactly the right time", the incredibly low (if ANY) odds that a civilization sends out signals at a given time of their technical development, and that we are at the same technical level to receive the signal. In other words: Those two planets, the two civilizations would need to be "synced" that such a communication (even if only one-way) can even happen.

Let's hypothetically and for shits and giggles assume that a star, like HD 164595, has an earth-like planet and that this signal is indeed genuine and authentic. Let's call the planet Mira.

Why would Mira send out a signal now, and not 4,505,000 years ago, or 150,000 years ago, or in 250 years, or in 3,450,000 years? The odds that this happens at the right time and we just happen to catch the signal....are pretty much ZERO, given that we're dealing with billions of years time spans on both sides.

Just 100 years ago, we invented radio/wireless communication. Only 500 years ago, we burnt witches. 2000 years ago, we watched slaves fighting with lions in arenas. You get the idea.

So I was thinking about this and concluded that it wouldn't make much sense if such a received SETI signal would indeed be genuine....UNLESS:

* A civilization on a far planet is conducting "sending out of signals" for hundreds of thousands, if not millions of years already. (Here again, the idea alone that a civilization sustains hundreds of thousands of years would be...mind boggling). Such a civilization COULD possibly scan star systems and planets, and they know very well that the odds of a signal being received at a particular time are minimal, UNLESS they target a system with signals "for eons".

So...this is highly speculative and total SciFi, but this is my only "rational explanation" how such a signal could ever be legitimate:

Such a civilization would build a giant sender/computer which is maybe around their star's orbit. The reason being that this would possibly be the only way to ensure that such a system would last for many, MANY thousands of years. Of course, the sender is equipped with a power source that makes sure the sender is working for hundred thousands, if not millions, of years.

This extraterrestrial SETI sender system could be scanning stars and keeps a list of them, so it knows what type of planets are POTENTIALLY, in a far future, developing intelligent life. For example, they could have found Sun and Earth a million years ago, and from calculations concluded it could be worth it to send signals in so or so years since there is a good chance that a high-tech civilization on Earth COULD come about which can receive the signals. (Of course they could also simply just blindly send signals to whatever stars/planets for millions of years)

What, according to any common sense is not happening that such a civilization is a "normal" civilization similar to ours where they "just happened" to be on the same technological level like us at this very moment. If such a signal is genuine, it must've been sent out for a long, long time.....

* Alternative scenario:

This extremely advanced civilization knows about means to communicate and space travel which are way beyond what we can even imagine. c is not a limit for them and they would never communicate with another advanced civilization with something primitive as radio waves.

Despite distances involved like 94 light years, the civilization has ways to observe a distant planet "instantly". So they know exactly when "the right time is". But they also know about the primitive technology at the receiver side and they know that the receivers can only use radio communications. So they use radio signals since this is the only tech the receiver can "understand" at this given moment. And they could time the signals so they arrive "at the right moment".

THIS theory is somewhat interesting since it would mean they noted how we invented radio, which by coincidence was about exactly this time, 94 years ago in 1922.

WOW:

https://en.wikipedia.org/wiki/History_of_radio

On 31 August 1920 the first known radio news program was broadcast by station 8MK, the unlicensed predecessor of WWJ (AM) in Detroit, Michigan. In 1922 regular wireless broadcasts for entertainment began in the UK from the Marconi Research Centre 2MT at Writtle near Chelmsford, England.

This is SPOT ON!! I didn't expect it being the exact same year!

So with their tech they witnessed this and immediately started to send out signals, and now it's exactly 94 years later - the distance to this particular star is 94ly, the time it takes for the signal to travel.

 

[John Connor]

When I got my new laptop in 2003 I installed the SETI screensaver. It was cool, but the damn laptop ran hot as hell and got rid of it. I did read in a Popular Science mag. many years ago about making your own radio telescope using a satellite TV dish and a dipole. Always wantd to make it, but I don't have that mag. anymore or know if it's buried somewhere amongst my crap. Now that was waaaaay before SDR's so I wonder what can be built now?

 

[sandorski]

There's only one way to answer that question: By trying.

 

[flexy]

I did read in a Popular Science mag. many years ago about making your own radio telescope using a satellite TV dish and a dipole. Always wantd to make it, but I don't have that mag. anymore or know if it's buried somewhere amongst my crap. Now that was waaaaay before SDR's so I wonder what can be built now?

Holy crap, the idea to build your own radio telescope from a satellite dish is super-interesting. I didn't know this would be possible. I will definitely spend some time googling this.

From the recent "signal" news there, I came up with some ideas how to possibly filter out suitable targets

* Scan only stars with a max. distance of about 100 light years. Because this is when we started using radio here on Earth, and I am still intrigued that this supposed signal (if it is one) was sent out at the exact same time when we started radio broadcasts. Also...if a civilization sends out signals to stars much further away, it sort-of becomes pointless. 100ly or so, even if still totally out of reach for us today, might, at some point in the future, become a still "reasonable" distance...

* Scan only stars of type G, like our sun. Given there are billions of stars, an intelligent civilization might apply some type of filter where they send to, rather than send to millions of stars "randomly". It makes sense that one of those criteria could be that they send to stars of the same type, and to think that THEIR reasoning is also that the receiver, at some point, comes to that conclusion..simply because it's a common factor between two systems that can be established, even over long distances.

Some of the nearest G-type stars known to have planets include the Sun, 61 Virginis, HD 102365, HD 147513, 47 Ursae Majoris, Mu Arae, and possibly Alpha Centauri.

Not an expert by any means, and possibly SETI does this already, but I can think that the odds to find a signal from such stars would be best.

 

[John Connor]

Yeah, it's interesting. You just need a very high GHz receiver though. The current crop of SDRs I'm familiar with go up to no more than 1300 MHz or there abouts. The HackRF One goes up to 6GHz. I've read that you should be scanning at least 11GHz. I'm willing to bet some Ham Convention will have a dude there that sells microwave equipment. I've seen it myself, but never payed too much attention to it. Then you need to use an LNA near the antenna.

I also think the dish size might be a factor as well. But it's an interesting project that I read about. I wish I could find that mag. It was either Pop Sci or Pop Mechanics. Was an issue during the mid to late 90's when UFO's and aliens were all the rage due in part to the X-Files. LOL!

 

[nakedfrog]

We're scanning the skies with SETI on various radio frequencies, not because it's an effective means to find an extraterrestrial civilization, but it's the ONLY means we currently have.

There was some hype the recent days again because SETI found a POSSIBLE signal https://forums.anandtech.com/thread...resting-signal-from-star-in-hercules.2485041/
but of course the usual caveats apply. And one of the biggest caveats and reason to criticize then entire SETI search effort...would be: WHAT ARE THE ODDS?

And those odds are, admittedly, extremely, extremely small.

I think that's basically what it comes down to. As far as we know, the odds aren't zero. I think it's just part of the human spirit to try, even if it probably is a doomed project.

 

[Sheep221]

I've been on DC scene for a while and I never did SETI, it's a project that does nothing for humanity, for research, for society, it has no sense. Sorry to anyone who had been doing it for years on their computers. Some extraterrestrial life probably does exist out of reach of any SETIs sensors, receivers or whatever equipment they are using to collect data, the area they do cover is probably very small in context of outer space.

 

[Puffnstuff]

If they'd just turn those antennas towards the local building supply store parking lot or Mexican restaurant they'd find those elusive aliens right away. In reality they aren't going to find anything but stray signals that we broadcast ourselves. I mean when watchers can get all excited about signals coming from an old Russian satellite....hmmm? We could all pitch in and create a fund me to build a new secret satellite and place it in orbit to broadcast fake alien transmissions for our own amusement.

 

[Charmonium]

There's one possibility where you would see a civilization produce radio signals for many millenia and possibly many millions of years - if they don't follow the same sort of exponential development curve that humans have since the industrial revolution.

You have to remember that civilization from say 3000BC to about 1000AD wasn't that different. You were still looking at all of the same basic technologies and more or less the same basic levels of understanding. The only thing that propelled humans forward was the development of the scientific method and the use of that in place of other less practically oriented mindsets.

So even if you imagine an alien race similar to humans, it's not a huge stretch to imagine that it might take them thousands of millenia to develop past the point of using EMF for communication. Hell, they might spend several thousand years at the Marconi stage of development rather than just a decade or so.

And if they aren't very much like humans, then certainly all bets are off. The most likely place for life to develop isn't on land but in salty oceans with hydrothermal vents. You could have advanced civilizations that don't need to colonize land until very late in their development - sort like how we have no real need to colonize Mars or the moon.

 

[nerp]

It would only fail if it searched the entire universe and found nothing. That will never happen because the universe is expanding. Therefore no, it is not doomed to fail. It might end before the search is complete, but I don't know if failure is the right word for it.

 

[flexy]

Related to the above post:

While science is still not 100% certain about the future (and origin) of the universe, how you interpret "the universe is expanding" is not correct.

When scientists talk about the expanding universe, they more mean "the space" between galaxies, star system, planets etc. While it is true that within the next billions of years of course new star systems, planets etc. are born as well (which possibly might develop life at some point), OVERALL, the universe is actually becoming "emptier". With the increased distances between systems (because of expanding space), in billions of years, each system, star, planet etc. will be further away from others so that ultimately, t(talking about billions of billions of years in the future) the chances to discover life (now technically and mathematically speaking) would be getting lower. At some point, any planet would find itself "alone" in the universe since all other systems have drifted so far away and beyond that we can can not even discover them, effectively meaning the universe has become empty.

On the other hand, now talking about the far, far (potential) future (end) of the universe, those time spans involved are so long so that they would be far longer than a civilization might last, meaning this expansion (and "death") of the universe will likely not play a role when it comes to searching for extraterrestrials. (Besides the incredible vastnesn of the universe of course)

Sorry had to nit-pick here, but the notion that the search should in time produce a result "because of the universe expanding" just struck me as not correct at all.

 

[nerp]

Yes, this is true. But there are still supernovas giving birth to new solar systems thus there is the possibility of lifeforms evolving and becoming intelligent. By the time every bit of energy in the universe has been spent, the timescales are so vast and distant into the future, it's tough to say when the end will actually occur. Not only that, we're talking about three dimensional space. If we detect parallel universes and begin to find ways to interact with them, our notion of the end of the universe is suddenly much more complex.

Also, though the universe will theoretically grow cold and everything will spread out so much that everything breaks down, there still will be planets and hunks of matter floating in the universe. We know that at the bottom of our ocean whole ecosystems thrive in the absence of oxygen and sunlight. Our universe might seem dead but there could still be some organism alive under a frozen ocean somewhere out there.

 

[MongGrel]

SETI has always been a shot in the dark, I used to DC there a bit long ago.

Cancer research etc always seemed more worthwhile to me, and I have not even done that i awhile I guess.

 

[Charmonium]

I read one article today saying that heat death of the universe could come in 2.8 billion years - which is a little odd since our sun still has about 5 billion or so years yet to go.

 

[Sheep221]

And if they aren't very much like humans, then certainly all bets are off. The most likely place for life to develop isn't on land but in salty oceans with hydrothermal vents. You could have advanced civilizations that don't need to colonize land until very late in their development - sort like how we have no real need to colonize Mars or the moon.

Since they don't contain anything usable, no one will be colonizing these.

Yes, this is true. But there are still supernovas giving birth to new solar systems thus there is the possibility of lifeforms evolving and becoming intelligent. By the time every bit of energy in the universe has been spent, the timescales are so vast and distant into the future, it's tough to say when the end will actually occur. Not only that, we're talking about three dimensional space. If we detect parallel universes and begin to find ways to interact with them, our notion of the end of the universe is suddenly much more complex.

Also, though the universe will theoretically grow cold and everything will spread out so much that everything breaks down, there still will be planets and hunks of matter floating in the universe. We know that at the bottom of our ocean whole ecosystems thrive in the absence of oxygen and sunlight. Our universe might seem dead but there could still be some organism alive under a frozen ocean somewhere out there.

Energy cannot be spent per se, energy cannot be created or destroyed. It is always about transferring it from one form to another different form.