Will we ever communicate with extraterrestial life in a reasonable time frame?

[MotherMayhem]

Granted that life exists somewhere. Just by stating that are 200 billion stars in the Milky Way galaxy tends to make us believe that intelligent life is close by.

We need to set a limit of 100 years to send and receive one answer. This necessary requirement will greatly reduce the possibility of any contact.
How many planets similar to Earth are within 50 light years?
What are the energy requirements to send that message?
What is the lowest signal we can reliably detect?

Many star systems contain two and three stars. Will planets in such systems have stable orbits to allow life billions of years to evolve?
Even if we find planets that can harbor life today, what was the history of such planets? We do not know.

Ohhhh, I'm sooooo sooorrrry I didn't get back to you in what YOU call a "reasonable time frame".. but I had alien stuff to do!
Wow... just...wow...
I'm gone for 5 years and you go and talk about me to all your friends on the internet!

You are so not getting the Milky way I picked up on my way back now.

 

[sbrothy]

If we have time enough (I'm talking geological time here) E-sail might be an alternative. Though I'm not even sure the we, or indeed the Milky Way, is still here when something returns.

 

[ohwilleke]

Well, when you looked it up on Wikipedia, you would have discovered there are 130 K, G and F type stars within 50 light years. You also, when you looked it up on Wikipedia, learned that estimates from Kepler are that 1.4-2.7% of such stars have planets in their habitable zones. That's 2-3, one of which is the sun.

So, there are 1 or 2 candidate stars. To have a civilization, this requires that the star not only has planets in the habitable zone, but that these planets are habitable. The sun has, arguably four: Venus, the Earth, the Moon, and Mars. Only one is habitable.

The rest is speculation, but I point out:

• For half of earth's history, there were no eukaryotes
• For 75% of eukaryote history, there were no multicelluar organisms
• For 99.5% of multicelluar life history, there were no people (genus homo)
• For 99.5% of human (genus homo again) existence, there was no civilization.
• For 99% of civilization, radios did not exist.

Give all that, 1 or 2 candidate stars does not seem like a lot.

The argument that there are only four candidates in the solar system, a priori (we've probed enough to rule out advanced civilizations on many them by now) seems low.

Carl Sagan, when pressed to consider the question of where in the solar system it was possible to support some kind of life in a glossy illustrated book I recall reading as a kid (I can't recall the title), came up with about a dozen. There could be blimp-like creatures in the atmospheres of Jupiter or Saturn, there could be life below a frozen ocean on Titan. There could be life on Neptune or Pluto, or on several other moons in the solar system. And so on. NASA thinks so too.

Movies and TV tend to imagine each different world as having only one ecosystem, but life only needs one tiny microenvironment to emerge, and that can happen in one little ecosystem corner on a world that is predominantly uninhabitable.

Now, one factor is that SETI has made a concerted effort to look for possible communications from other life forms in space for decades and not found anything. This puts a ceiling on the strength of a signal that could be receiving unless we receive this alien civilization's very first transmission in our direction. Most conceivable civilizations within 50 light-years of Earth that could send us a message would have done so already and been discovered, if the signal was strong enough for SETI to hear.

But if we did discover an alien civilization, right now would be a pretty plausible time to do so, because the power of our "telescopes" (broadly defined) has improved dramatically in the last decade or two. So, we can now detect all sorts of signals from space that we were previously deaf to. If some alien civilization is regularly transmitting signals in our direction, then we are likely to discover any too weak to hear before the latest wave of "telescopes" but within our power to detect now, any time now. Major new discoveries from new telescope technologies tend to be front loaded.

Also, because it doesn't seem to have been mentioned yet, the primary way for scientists (lots of them) to structure the question asked in this thread is through analysis of Drake's Equation. There are, for example, sixty pre-prints at arXiv that discuss this equation.

 

[MotherMayhem]

If we have time enough (I'm talking geological time here) E-sail might be an alternative. Though I'm not even sure the we, or indeed the Milky Way, is still here when something returns.

My Milky Way had BETTER be here when I get back!
If anyone eats it while I've popped out, I'm getting out the lazer beams so help me!

 

[DennisN]

NO! Just no! Get out of of my TV! :P

What's even worse is that I like a few programs on History Channel ("Forged in Fire" for instance) but suddenly up comes this "Ancient Astronauts" series which actually gives the man screentime!!

"Ancient astronaut theoriticians say Yes!"

The funny thing is that I understand (at least I think I do ) why the ancient astronauts/ancient aliens belief system is popular among some people. It is an incredibly thrilling and compelling story. And numerous science fiction stories have used it (e.g. Sphere, Stargate, Prometheus and Indiana Jones and the Kingdom of the Crystal Skull).

 

[Jaime Rudas]

Humans are too primitive

Regarding whom are humans too primitive?

 

[sbrothy]

The funny thing is that I understand (at least I think I do ) why the ancient astronauts/ancient aliens belief system is popular among some people. It is an incredibly thrilling and compelling story. And numerous science fiction stories have used it (e.g. Sphere, Stargate, Prometheus and Indiana Jones and the Kingdom of the Crystal Skull).

Yeah, But as someone metioned (@sophiecentaur ?), Däniken is something you read when you're 16 and spiritually searching until you look out into the cosmos and realize there's no need to come up with crazy stories. Reality is plenty crazy as it is. :)

 

[sbrothy]

My Milky Way had BETTER be here when I get back!
If anyone eats it while I've popped out, I'm getting out the lazer beams so help me!

I'm gonna quick-draw my Nicoll-Dyson beam.

 

[Hyku]

Regarding whom are humans too primitive?

six-eight million years ago, we shared a common ancestor with the chimpanzee and the bonobo. To this day, we share 98.8% of our DNA with the chimp.*

Chimpanzees wage war, and they are sadists. **

The myriad 20th century atrocities are common knowledge. Three common causal factors were - a disillusioned desperate population - the emergence of a leader - and the population being bombarded by propaganda that targeted emotion - not intellect. I argue that the populations subsequently behaved like chimps.

* https://www.amnh.org/exhibitions/pe...ding-our-past/dna-comparing-humans-and-chimps

** https://duckduckgo.com/?q=chimpanzee+warlike+sadists&t=ffab&ia=web

 

[Jaime Rudas]

six-eight million years ago, we shared a common ancestor with the chimpanzee and the bonobo. To this day, we share 98.8% of our DNA with the chimp.*

Chimpanzees wage war, and they are sadists. **

The myriad 20th century atrocities are common knowledge. Three common causal factors were - a disillusioned desperate population - the emergence of a leader - and the population being bombarded by propaganda that targeted emotion - not intellect. I argue that the populations subsequently behaved like chimps.

* https://www.amnh.org/exhibitions/pe...ding-our-past/dna-comparing-humans-and-chimps

** https://duckduckgo.com/?q=chimpanzee+warlike+sadists&t=ffab&ia=web

Nice set of non sequiturs

 

[Hyku]

Nice set of non sequiturs

What you meant to say was - that was a nice set of non sequiturs.
So you wrapped an ad hominen fallacy in a cloak of grammatically flawed sarcasm.

Please explain the flaws in "The myriad 20th century atrocities are common knowledge. Three common causal factors were - a disillusioned desperate population - the emergence of a leader - and the population being bombarded by propaganda that targeted emotion - not intellect. I argue that the populations subsequently behaved like chimps."

Did you read the 2 cited sources?

 

[Jaime Rudas]

What you meant to say was - that was a nice set of non sequiturs.

What I meant to say is that correlation does not imply causation. In other words, I cannot find a causal relationship between the following statements:

Humans are too primitive.

We share 98.8% of our DNA with the chimp.

Chimpanzees wage war, and they are sadists.

The myriad 20th century atrocities are common knowledge.

The population is disillusioned and desperate.

A leader emerged.

The population is being bombarded by propaganda that targeted emotion - not intellect.

The population behaves like chimps.

 

[pinball1970]

IS this thread discussing the quest for life forms or the quest for advanced civilisations? I would not be surprised if some life forms were discovered within a decade or so but that is many orders of magnitude from chatty little green men.

Fair enough, I was just pointing out active research past and present for ET life and planets they could be on.

 

[Sheik Yerbuti]

I think a missing factor in the discussion about contacting ET is the question of how long we will be homo sapiens. The 100,000 light years that are our galaxy is roughly the same as the age of homo sapiens sapiens. Assuming that in the distant future time will be no barrier to communication (yeah- big assumption), they could be us. Especially since we try to contact other civilizations, our first contact could be ourselves from 10,000 years in the future trying to contact other civilizations. Or time can't be conquered. I find it interesting to consider, though.

 

[MotherMayhem]

I'm gonna quick-draw my Nicoll-Dyson beam.

You could try, Earth Man...

 

[sophiecentaur]

Fair enough, I was just pointing out active research past and present for ET life and planets they could be on.

There is a well specified goal for this research and it is producing more and more data about the likely reasons for the appearance of life on Earth. I would say that it's been 'proper Science', so far. I'm not sure where it would take our technology in a practical, useful direction but we constantly get unforseen benefits from well directed research.

However, the thread is about contacting LGM and there are plenty of reasons to doubt that it is at all likely. We've had (sort of) Anthropology and an embarrassing amount of Science Fiction but the timescales indicate that, without a magical change in our technology (a massive change in the Science) the overlap between two suitable civilisations for communication is hardly (=not) worth considering. There are many other, much more useful directions in which our resources could be spent.

 

[sophiecentaur]

Or time can't be conquered. I find it interesting to consider, though.

oh yes. But not to spend too much money on. (I spend more time on Wordle)

 

[BWV]

Well, when you looked it up on Wikipedia, you would have discovered there are 130 K, G and F type stars within 50 light years. You also, when you looked it up on Wikipedia, learned that estimates from Kepler are that 1.4-2.7% of such stars have planets in their habitable zones. That's 2-3, one of which is the sun.

So, there are 1 or 2 candidate stars. To have a civilization, this requires that the star not only has planets in the habitable zone, but that these planets are habitable. The sun has, arguably four: Venus, the Earth, the Moon, and Mars. Only one is habitable.

The rest is speculation, but I point out:

• For half of earth's history, there were no eukaryotes
• For 75% of eukaryote history, there were no multicelluar organisms
• For 99.5% of multicelluar life history, there were no people (genus homo)
• For 99.5% of human (genus homo again) existence, there was no civilization.
• For 99% of civilization, radios did not exist.

Give all that, 1 or 2 candidate stars does not seem like a lot.

So if you grant 1-2 candidate stars from this plausible argument you then have the probability that some life form evolves into a technological civilization times the probability that this occurred in a compatible time frame for communication , if if took roughly 3 billion years of life before humans got radios and we generously allow that we will remain around for the remaining billion years or so remaining for life to exist on earth, then we would have existed for roughly 25% of lifespan of life on Earth

 

[sophiecentaur]

generously allow that we will remain around for the remaining billion years

incredibly generous. I'd give us only a few thousand years. I admit it's true that our present technology (not civilisation) has pretty robust data records but we'd only need a 'book-burning' cult to emerge and we could well be back to square one in a very short interval.
In all these imagined scenarios I see an up to date form of religion at work. A cult of optimism about survival of homo sapiens, compared with what all fossil records indicates a warped timescale of our possible future.

 

[BWV]

incredibly generous. I'd give us only a few thousand years. I admit it's true that our present technology (not civilisation) has pretty robust data records but we'd only need a 'book-burning' cult to emerge and we could well be back to square one in a very short interval.
In all these imagined scenarios I see an up to date form of religion at work. A cult of optimism about survival of homo sapiens, compared with what all fossil records indicates a warped timescale of our possible future.

Don’t think you give us monkeys enough credit- we survive and thrive in more environments than any other animal - we are by far the most successful and adaptable animal on the planet, even more than rats or roaches (who’s current range stems from their parasitical relationship with us).

 

[sophiecentaur]

we are by far the most successful and adaptable animal on the planet,

Tardegrades need no tech to survive well outside our sustainable range. You have to exclude situations like space craft and antarctic stations which are only there by the grace of the rest of the population being able to produce food etc.. And I'd ask my same old question about how much of your wealth would you spend on an ark for a lucky few to survive? Unless you are extremely altruistic, I'd suspect that, when the compost hits the fan, you would look after yourself or your close family. And we all end up dead.

But don't we need to be more mature about this and accept that it's all very finite? The party ends eventually and that is sooner than we might wish. The end of the party for each of us is only a few decades, max but why is that a problem?

 

[russ_watters]

incredibly generous. I'd give us only a few thousand years. I admit it's true that our present technology (not civilisation) has pretty robust data records but we'd only need a 'book-burning' cult to emerge and we could well be back to square one in a very short interval.
In all these imagined scenarios I see an up to date form of religion at work. A cult of optimism about survival of homo sapiens, compared with what all fossil records indicates a warped timescale of our possible future.

Is your pessimism based solely on "could"? Why is "could" only applied to the pessimistic slant and not the optimistic one?

IMO the pessimistic "could" is really thin. I recognize it's only been maybe 10,000 years but the number of successful civilizations of which we have little knowledge is very small - it's practically an oxymoron. To get back to hunter-gatherer or extinction would pretty much take a global calamity like an asteroid the size of Texas and even that might not be enough.

But either way, the pathway to longevity is there and fairly obvious. I'd put the odds/median at better than 50/50; 500million years.

 

[russ_watters]

The argument that there are only four candidates in the solar system, a priori (we've probed enough to rule out advanced civilizations on many them by now) seems low.

Carl Sagan, when pressed to consider the question of where in the solar system it was possible to support some kind of life in a glossy illustrated book I recall reading as a kid (I can't recall the title), came up with about a dozen. There could be blimp-like creatures in the atmospheres of Jupiter or Saturn, there could be life below a frozen ocean on Titan. There could be life on Neptune or Pluto, or on several other moons in the solar system. And so on. NASA thinks so too.

Sagan had a vivid imagination, but I doubt he actually believed there was a significant possibility of life on Jupiter's moons (much less Jupiter itself!), only that we couldn't completely rule it out. He also died 8 years before the Mars exploration Renaissance which so far has produced no evidence of current or past life on Mars, despite ample evidence of water. What @Vanadium_50's timeline tells us is that given excellent conditions such as on Earth, life seems to spring forth almost immediately, but the major steps in evolution take eons longer. While not impossible, the lack of success finding life on our nearest neighbor makes it far less likely that it arose at all in other locations in the solar system, much less evolved any significant complexity. This suggests life requires good conditions (but is also all but inevitable in very good conditions) whereas complex/intelligent life likely requires excellent conditions and a long time.

I discussed the other end of that (that doesn't imply it won't last a long time) in my prior post.

 

[DroolingApe]

One of the biggest problems with phoning ETs is simply power requirements. Generating a signal that will be detectable is hard, which is why I consider the likelihood that any successful communication needs to use a star as their carrier, and doing something to modulate the light from their star to carry their message. So the question becomes, how to best turn a star into signal lamp? Giant space bound louvers sounds pretty silly. Just placing a mask in the way could produce a detectable pattern, especially if the pattern intentionally generates interference patterns which might look sufficiently "interesting" to distant observers, but would be highly directional. Probably best to do it with a nearby star instead of your own, making it ever more difficult to accomplish. Of course, all this speculation really does is show us how unlikely contact is.

 

[berkeman]

Thread paused for Mentor review. At least one of the posters participating in this UFO/UAP subthread has a very long and checkered infraction history at PF...

 

[berkeman]

A subthread about UFOs has been deleted. Please stay on topic for this thread, which is about remote communication via radio, etc. Thank you.

Thread is reopened provisionally.

 

[sbrothy]

All of what I wrote down is maybe two terms in the Drake Equation.

Extrapolating from a single data point is, well, better than from zero data points, but not much. And there are things we just don't know - multicelluarlsm (is that a word?) evolved two dozen times, but was lost in most instances. Why? It also appears to have evolved late. Again, why?

One could argue that you don't get intelligence without a metabolism based on oxidation rather than photosynthesis and reduction, so you need to wait until the atmosphere is mostly plant poop. Maybe so. But this will reduce the probability a given planet will ever develop intelligence. Probably lots of planets evolve cyanobacteria, who then eat all the CO2 and possibly water in the atmosphere, causing the planet to freeze and that, as they say, is that.

I would not be surprised if pond scum (or at least extinct pond scun) is common, but anything beyond that is rare. But what do I know? This thread isn't about science - it's about guesswork.

I know I'm on very thin ice here as the thread is only provisionally open awaiting someone like me to speculate further and be banned. Forgive my ignorance then, but isn't it possible, if a planets magnetic field is weaker allowing more energetic radiation through and thus pressuring both random DNA mutation (I just know you'll say cancer here :) ), photosynthetic efficiency and ultimately "purple people needing to breath less"?

 

[Vanadium 50]

if a planets magnetic field is weaker ... ultimately "purple people needing to breath less"?

So it would be easier to breathe on Mats? I don't think this follows.

 

[ShadowKraz]

So it would be easier to breathe on Mats? I don't think this follows.

I think sbrothy was trying to indicate that the "purple people needing to breath (sic) less" would have their metabolism based on photosynthesis or something very similar; CO2 breathers rather than O.
And, btw, it is very difficult to breathe on Mats if you are being pinned by a bigger wrestler. lol. (You should see some of the typos I let get past me when I write: "SHUT UP," he explained.)

 

[ShadowKraz]

Don’t think you give us monkeys enough credit- we survive and thrive in more environments than any other animal - we are by far the most successful and adaptable animal on the planet, even more than rats or roaches (who’s current range stems from their parasitical relationship with us).

You misspelled "invasive and destructive".

 

[Vanadium 50]

You get 5-10x as much energy per mole of oxygen by burning sugar as opposed to photosynthesis. You also only get half as much light on Mars. Intelligence is energetically expensive. I don't think it is an accident that intelligence exists only in the animal kingdom.

 

[sbrothy]

I think sbrothy was trying to indicate that the "purple people needing to breath (sic) less" would have their metabolism based on photosynthesis or something very similar; CO2 breathers rather than O.
And, btw, it is very difficult to breathe on Mats if you are being pinned by a bigger wrestler. lol. (You should see some of the typos I let get past me when I write: "SHUT UP," he explained.)

Yeah. That was my point. I may have been a little too sarcastic about it though.

EDIT: Because I kinda know how @Vanadium 50 (don't) suffer fools like me. :P

 

[PeroK]

You get 5-10x as much energy per mole of oxygen by burning sugar as opposed to photosynthesis. You also only get half as much light on Mars. Intelligence is energetically expensive. I don't think it is an accident that intelligence exists only in the animal kingdom.

"The Thing from Another World" featured a malevolent plant-based alien:

https://en.m.wikipedia.org/wiki/The_Thing_from_Another_World

 

[Hornbein]

"Will we ever communicate with extraterrestial life"

I am not authorized to divulge such information.

 

[sophiecentaur]

I don't think it is an accident that intelligence exists only in the animal kingdom.

Some of my toadstool friends are pretty smart but I can't see them building a blast furnace. If you don't have the right physiology, there are limits to technological advancement.

Humans exhibit a high level of oxymoronic behaviour. On the one hand, some of them are desperate to meet space aliens but they don't a 'foreigner' moving in next door.