Beamed propulsion continues to be a particular fascination of mine, which is why I want to start a discussion tomorrow of Jim Benford’s latest paper on beamed sails and how they might be optimized for both performance and cost. Reading through Benford’s work, however, I also came across Chris Wilson’s recent articles in Slate, which discuss Jim and Gregory Benford’s work on interstellar beacons and the SETI ramifications. I want to be sure to point to Wilson’s How to Build a Beacon because I don’t see ‘Benford beacons,’ as they’re increasingly called, discussed much in the media, and Wilson does a fine job at setting the concept in context.
Messages into Deep Time
The two part Slate series (the first article is The Great Silence) considers humanity’s legacy and relates it to the issues raised by SETI. The Arecibo message sent in the direction of the globular cluster M13 in November of 1974 is Wilson’s point of departure. Carl Sagan and Frank Drake set up the famous message in the form of 1679 binary digits that could be decoded into a set of simple pictures showing the image of a human being and other aspects of our existence including a double helix and a graphic of the Solar System. There is rudimentary content here, but the idea that such a fleeting signal would be received is dubious, given the odds on its happening to have a receptive civilization in its path in the first place. As Wilson writes:
Even if we left the Arecibo telescope squealing out its signal until its power ran out and its hardware rusted, there’s virtually no chance that the emanations would get anywhere in particular, and hang around long enough to be seen or heard. The only way we’ll make contact is if we can make a beacon that keeps going for millions or billions of years after we’re gone.
Two of the signals sent to nearby star systems by Alexander Zaitsev from Evpatoria show up as part of the same argument, the point being that for an interstellar beacon to be noticed, it has to transmit for a long period and be energy-efficient as well. By ‘a long time’ I mean potentially eons, because such a beacon might be set up as the final gift to the universe from a dying civilization, and it might not be found for millions of years. Enter the Benford brothers, whose work on cost-optimized beacons we discussed here in articles like A Beacon-Oriented Strategy for SETI (and you can use the search function to pull up other Centauri Dreams stories on this work).
Signature of a Cost-Optimized Beacon
If you’re building such a beacon, you’re naturally going to think in terms of efficiency, as the cost of delivering a powerful signal continuously over a vast period of time would be mind-boggling. An efficient beacon is one that would choose its coverage area carefully to optimize the chances of being heard, and one that would offer short pulses that recur over regular periods. Note what a departure such a signal would be from the kind of signal conventional SETI is optimized to find, its searches running quick sweeps past stars to find continually broadcasting beacons. A Benford beacon’s signature would be intermittent, a brief pulse that would eventually recur.
No technology available in the near-term will allow us to deliver powerful signals every minute of the day over a span of multiple epochs… But we might be able to make a beacon that works more efficiently, by targeting only those star systems where life seems most likely, and then pinging them each in turn, repeating the cycle every few months or so. Presumably, if a curious civilization caught one transmission, it would train its telescopes on that exact spot until the next part of the beacon’s message arrived. This more sensible approach—a sort of Energy Star specification for SETI—would save enough power to keep the beacon running for millions of years.
If we’re trying to receive such a signal, slow and steady scans of the galactic plane might turn it up in the form of a short narrowband burst that would eventually repeat, which would call for longer ‘dwell times’ — the time devoted to looking at a particular target — and a good deal of patience. Gregory Benford notes that a civilization building such a beacon in our system might locate it at roughly 0.5 AU, allowing for plenty of energy for the beacon’s solar cells. Such a beacon would also face the threat of space debris, given that we’re talking about an artifact that will need to survive for hundreds of millions of years — deep time — and remain functional. Advanced robotics are one way Benford sees to repair damage and keep systems running.
Monument to a Lost Civilization
Benford beacons get around the synchronicity problem that bedevils those obsessed with communication with extraterrestrial civilizations. We have no way of knowing the average lifespan of a technological culture, and it’s possible that such lifetimes are measured in mere hundreds of years or millennia. A long-term beacon keeps sending detectable signals long after the civilization that created it is gone, perhaps as a monument in the fashion of the pyramids. Wilson writes about the Star Trek episode called ‘The Inner Light,’ in which Captain Picard lives out an entire existence on an unknown planet as he experiences an alien mind-probe, only to come to the end of the message and awake to find that a mere 25 minutes have passed.
Would our own species build a Benford beacon if catastrophe loomed? It’s an interesting notion, and it gets around the concerns that some have expressed about METI (Messaging to Extraterrestrial Intelligence), in that a society that builds a ‘funeral pyre’ beacon isn’t even thinking about a response, whether dangerous or otherwise. Wilson suggests a kind of beacon insurance system — build an interstellar beacon that is programmed not to function unless it loses all contact from its creators for an extended period. If it determines the creating culture is extinct, it switches on to send out the valedictory. A civilization dies, but in the remote future, perhaps another detects and decodes its final thoughts. There’s a bleakness in the concept, and yet at the same time a certain degree of grandeur.
To explore Benford beacons at the source, see James Benford et al., “Cost Optimized Interstellar Beacons: METI,” available here, and Gregory Benford et al., “Cost Optimized Interstellar Beacons: SETI,” available here.
Interesting you bring this up Paul . Oct National Geographic had a story on the PETM ,a not impossible scenario for us now if the permafrost melts and there is significant arctic methane leakage.
In that era there were no large mammals but small ones, apparently because of lack of oxygen. In that scenario maybe a few humans would survive but with most large mammals gone …which would be elephants and apes as well would there be another intellegent species. I would argue there would be hope in crows,ravens and parrots. I am sure we could even train them to maintain a beacon and other evidence of our existance. Could we train them to protect the earth from asteroids?
Does this make sense?
Build a Dyson sphere to capture 100% of the energy of a red dwarf star. But the sphere has a gap, through which the signal is sent. The energy captured from the star is stored, and used in sending the signal continuously for eons. The sphere rotates and precesses on all 3 axes of rotation, so that at various times the beacon will be directed at all points in the sky.
On a slightly related note, you’ve mentioned that a Dyson sphere might appear to be an infrared source. But wouldn’t an advanced civilization be able to capture all energy, even infrared and radio waves? So there wouldn’t be any radiation at all to detect.
If I buy 100 lottery tickets I have greatly increased my chance of winning. However my actually chance of winning is still pathetically small. It all hinges on discovering the probability of winning the SETI “lottery” before we can decide on the utility of buying more tickets.
A stellar beacon, why not a stellar heliograph. At some distant point between the Sun and the system you wish to communicate with place, well basically a venetian blind that open and closes to turn the light from the Sun on and off as seen from the target system.
My first thought on how to make a very energy efficient beacon is to use the same occultation principle now used in Kepler’s planet hunting: Set up a bright “light” source and place several objects in orbit in it at various radii so that the pattern of occultations forms a meaningful message. Note that this will probably require thousands of objects. However, the longevity of the beacon would be challenged by orbital resonances, et cetera, so I don’t know if it is very feasible. It should help if the orbiting objects are very light (not much mutual gravitation). It would also help the angular visibility if the orbiting objects are very large compared to the light source, thus implying they should be very low-density. Of course, the bit rate would be extremely slow unless some exotic matter was used (high mass in a small space = fast close-in orbits). The nice thing about this, once you set it up, gravity keeps the signalling going. Worth a more involved analysis?
Paul, as you stated,
“If you’re building such a beacon, you’re naturally going to think in terms of efficiency, as the cost of delivering a powerful signal continuously over a vast period of time would be mind-boggling. An efficient beacon is one that would choose its coverage area carefully to optimize the chances of being heard, and one that would offer short pulses that recur over regular periods.”
This got me thinking, why couldn’t a sufficiently advanced civilization use natural occurring objects like stellar black holes, or neutron stars or even white dwarfs as beacons?
In fact once you can get to one, it would take very little technology and energy to use materials such as debris, ie. asteroids and plot orbits that would collide with the star or black hole in a mathematical pattern. Anyone of our level of technology or higher should be able to detect the signal easily enough.
Current SETI indeed runs relatively quick sweeps past stars to find continually broadcasting sources. A handfull of anomalous and/or non-repeatable signal candidates have been detected, as mentioned in an earlier article. I am wondering if any of these non-repeatable candidate signals have been analyzed for content. Do any of the SETI searches record these signals so they can be analyzed again ? Even if those non-repeatable signals are just part of a larger potential message we migth still be able to identify content or at least non-terrestrial artifiality of the signal.
No.
Among the major objections: acquiring the material to build the Dyson sphere. Launching the material into high inclination orbits. Collision avoidance between the vast number of satellites comprising the sphere.
While Dyson spheres make neat big dumb objects for science fiction stories, they do not seem a very practicable prospect.
stephen, the reason why a Dyson sphere or more plausibly swarm would be an infrared source is basic thermodynamics: it needs to get rid of its waste heat, and that is what waste heat looks like.
Paul, I don’t follow this post at all. One minute you have a dying civilisation, and the next it leaves behind it an engineering work that only a dynamic, optimistic, outward-looking and extremely wealthy civilisation could hope to attempt. Does not strike me as very likely.
Stephen
Oxford, UK
What if the WOW! signal was one of these? Have we tried listening to that area of sky again? What if the cycle isn’t a few months, but several decades? (What if they’ve got a LOT of targets on their ping list?)
“While Dyson spheres make neat big dumb objects for science fiction stories, they do not seem a very practicable prospect.”
Agreed. Concepts like these would be appropriate for a civilization eons more advanced that ours assuming progress continues. But if they were really that advanced they likely would not even need to capture solar energy on any scale as they might be adept at coaxing vast amount of energy from the fabric of the Cosmos in a way reminiscent of a small controlled big bang. Who knows? Certainly not me. But it is a lot of fun to speculate.
The second law of thermodynamics says no. There will always have to be some waste heat, which should be detectable as infrared. Though for a sufficiently advanced technology, the amount of waste heat could be quite tiny. On the other hand, such an advanced technology may well be ambitious enough to be manipulating a LOT of energy at once, meaning that even a tiny proportion of waste heat adds up to a lot.
Regarding the construction and the maintenance of a beacon — a big, difficult, and expensive project — I look at these not so simple suggestions:
– use a black hole, or a neutron star, or a white dwarf, we have to get at first, or
– build a Dyson sphere around a distant star, we have to get at first, or
– build a stellar heliograph at some distant point between the Sun and a distant star.
I think, it would be better to just build a beacon near to earth. Or even better: mankind should make preparations for existing very, very, very long *and* build a beacon *and* maintain it *and* get the results. As an intelligent species we should be able to manage this (well, this sounds like a tautology, if I inspect the pertinent definitions of “intelligent”).
Let us make a million years civilization project! As a minimum. This is much more fun than those depressing funeral and dying civilization things. By the way, dying never has any grandeur.
“Presumably, if a curious civilization caught one transmission, it would train its telescopes on that exact spot until the next part of the beacon’s message arrived. ”
We’ve gone back to look at the “Wow! Signal” location a few times, but there’s no permanent monitoring of it as far as I can tell. This is one of those assumptions that you would think would be true.. you’d certainly hope it would be. But in our own case at least, so far it hasn’t been.
“On a slightly related note, you’ve mentioned that a Dyson sphere might appear to be an infrared source. But wouldn’t an advanced civilization be able to capture all energy, even infrared and radio waves? So there wouldn’t be any radiation at all to detect.”
You cannot escape Entropy. No matter how efficient, in the long run any Dyson Sphere will heat up, and the only way to get rid of that excess heat is by letting it radiate outward.
A lightweight Dyson sphere is possible, sometimes called a Dyson bubble; it would be made of lightweight material, supported by light pressure alone (a statite balloon partially or completely surrounding the star).
The total mass of such a creation would be less than Ceres. This sort of creation could only collect a small fraction of the star’s light, as it couldn’t absorb much energy before becoming saturated; but it could collect enough to make a very powerful beacon.
Supernovae are among the most brilliant and powerful natural beacons in the Universe. It has been suggested that an ETI might use these stellar deaths to get the attetion of other intelligences by conducting METI in the direction directly opposite towards those in the observing zone of the exploding sun.
http://www.iar.unlp.edu.ar/SETI/seti-boston.pdf
Whether any astronomers on this planet have been watching for alien signals when a supernova is detected has yet to be determined.
As for making Dyson Shells, the original design as described by Freeman Dyson in 1960 is certainly possible, building a large number of independent habitats around a star. Think O’Neil colonies and similar concepts.
As with other astroengineering ideas presented here and elsewhere, I find it ironic that incredible ideas requiring seriously advanced technology are discussed in vivid detail, but when it comes to who will use them, the results usually end up being current humanity with no perceived or described enhancements.
This includes the Dyson Shells. It has long been assumed they will be big solid hollow spheres with people living on the inside. The late Robert Bradbury was one of the first to push for Dyson Shells not being just habitats for humanoids but actual hyperintelligent beings in themselves. Whether he will ultimately be proven right or wrong, no one can argue that he was not truly thinking outside the box.
https://centauri-dreams.org/?p=434
http://ieet.org/index.php/IEET/more/4606
mcirkovic.aob.rs/paper_v4.pdf
Luc Arnold has also written about ETI using large geometric objects transiting their suns which we may be able to detect.
http://www.obs-hp.fr/~larnold/homepage.html
Brian said on December 9, 2011 at 1:04:
“Presumably, if a curious civilization caught one transmission, it would train its telescopes on that exact spot until the next part of the beacon’s message arrived. ”
We’ve gone back to look at the “Wow! Signal” location a few times, but there’s no permanent monitoring of it as far as I can tell. This is one of those assumptions that you would think would be true.. you’d certainly hope it would be. But in our own case at least, so far it hasn’t been.
LJK replies:
The ATA effort at Hat Creek was supposed to end our decades of largely token and sporadic SETI efforts, at least for the radio spectrum. Then they ran into their budget issues and while they are back, it remains to be seen how often they will be monitoring on a 24/7 basis.
As for humanity’s own METI beacon, if it ever becomes a reality it will probably come from private investors with their own space utilization companies. We just have to convince some rich guy that he will be immortalized by transmitting his presence into the galaxy forever.
Astronist said on December 8, 2011 at 21:42:
“Paul, I don’t follow this post at all. One minute you have a dying civilisation, and the next it leaves behind it an engineering work that only a dynamic, optimistic, outward-looking and extremely wealthy civilisation could hope to attempt. Does not strike me as very likely.”
A technological civilization is not going to be deliberately broadcasting its presence into the Cosmos without a really good reason and with the presumption that they do not assume such actions will lead to negative results for themselves.
One plausible reason is that a civilization which knows it is dying for whatever reason and cannot escape its current situation may want to preserve itself in some manner so that its existence was not in vain, especially if its ages of effort and knowledge can be of interest and help to other societies. Beaming their knowledge and information into the galaxy with no fear of repercussions or concerns about wasting resources is a plausible idea.
Another reason for a cosmic beacon is religion. Belief in deities on this planet has certainly motivated most societies to make contact with others throughout history, though not always with pleasant results for one party or the other. Religion is also an institution that can endure for millennia, such as with the Roman Catholic Church.
If religion is part of the makeup of all developing intelligences, it is conceivable that a species might make a beacon to broadcast their Good News to all the perceived beings in the galaxy who do not yet know about the wonders of their deities. I can certainly see certain human religious groups and cults wanting to spread their beliefs to others beyond Earth, especially as they will likely be considered unwashed and in need of “salvation”. The results should be interesting, to say the least, especially if and when they run into another society that has very strong views about their own gods as well, or just are not big on being preached to in general.
http://www.wired.com/science/space/news/2008/06/alien_religion?currentPage=all
Dyson bubbles, like the other satellite swarm ideas still ought to be vulnerable to Kessler syndrome. Plus not only do you have the problem of launching large quantities of material into high inclination orbits, you then end up needing to brake them again. Again it seems to be a case of a “cool” idea rather than a realistic engineering prospect.
Astronist,
You must have missed my previous posts. I’ve set up a blog space where, if you like, we can discuss in detail technical issues.
http://argumentcity.blogspot.com/
Everyone is welcome, but I expect people to be on their best behavior.
Ljk: a “dying civilisation” may have a reason to leave a beacon, but they certainly won’t be able to afford its development or construction, nor do I think they will be particularly motivated to do so. Think the collapse of Yugoslavia or of the Soviet Union on a global scale!
Stephen
That would probably depend on how powerful they are when they start declining, how rapid and predictable their demise turns out to be, and how willing they are to perhaps hasten their own end to devote resources to such a project.
But one could also certainly consider a funeral pyre type concept analogous to things like the pyramids, or the Moai of Easter Island, as in constructs made not by a dying civilization, but by a civilization at the height of its powers committing to leaving a monument to the distant future for whatever reasons, which need not be rational, and with the construction of such an ambitious project itself being one of the triggers for the subsequent fall, leaving the beacon behind as a “funeral pyre”.
To me the idea of a Dyson Sphere is very much the product of a 20th century mind contemplating a solution to a 24th century problem.
There is in fact a jarring fundamental anachronism in the very heart of the idea, in that it is assuming a very current, present day capability in the technology of collecting and generating energy, and calling upon a hypothetically far advanced future capability to manufacture, construct, and maintain infrastructure, to basically scale up that primitive anachronistic present day capacity on a massive scale in a blunt brute force type of way to meet a distant future demand.
What does the term “dying civilisation” mean in the context of this debate. I put it to you that here this could only mean a powerful group generating huge surpluses, and whose continuance looked limited.
This reminds me a little of Western civilisation with its combination of wealth and chronically low birth rate. It is worth noting that we would find it unconscionable to reduce women’s access to education even if we found that it was the only way to secure our long term survival
Another anthropic example is if our future contained a split where almost all chose to be “downloaded” into a sort of cyber-world with a very low energy requirement, while a dwindling minority chose to live the classic human existence and found themselves surrounded by massive energy rich capital projects, but no legacy to pass on.
I conclude that an actual dying ETI civilization would look very different from examples that might have been set by previous ecological disasters in which civilised humans were located and this seems to have caused some confusion.
I was thinking of Dyson swarms or bubbles.
I was assuming residual energy might be in the form of EM radiation even less energetic than infrared: radio waves.
Thanks.
Obviously if a society finds out it is going to be destroyed by a giant space rock in a few days, for example, it is probably not going to have either the time or a big interest in making a METI beacon to send its information into the void.
I am referring to a scenario where a society finds out it will be coming to an end due to some geological or celestial or biological catastrophe and it does not have the capabilities to build and launch a worldship with lots of its members in time. However, they do have enough time to at least preserve who they are/were by various methods, including beaming everything possible about themselves into the galaxy and hoping for the best that someone someday somewhere will detect and translate their “gift”, to preserve their memory at the least and utilize their knowledge to the benefit of the recipient civilization at best.
Perhaps a truly far-thinking society will not wait until impending doom looms on the horizon but, realizing that even the biggest and most powerful civilizations have a shelf life, at the very least make plans to store their societal information in some protected place such as on various planetoids in deep space. There the facilities will remain largely apart from the main society while remaining in contact for constant updates to their records.
In the event these “libraries” lose contact with the parent society and it becomes clear after a while that no new data will be arriving, the facilities will be programmed to automatically start beaming their information into space, both to specific target systems that seem suitable or a wide broadcast. They will of course retain the data in the event that some expedition ventures into the system one day or the parent civilization recovers and becomes in need of all that knowledge otherwise lost on their home world.
This plan precludes the concerns expressed in this thread that a civilization facing extinction will not be terribly concerned about or have the time to preserve parts of itself via a METI beacon because they simply will not wait until the last minute to undertake such a project.
Humanity should consider such a plan as well. Some groups have already been thinking ahead, such as the ones preserving seeds in the Arctic, and there have been proposals to place our knowledge in caves on the Moon. The key point is that such ideas should be conducted NOW and not when impending doom is just around the corner. This idea also applies to the worldship concept, because waiting until the last minute to start planning that huge project is not realistic.
I would like to insist on *not* making plans for the time after our extinction but on making plans for avoiding our extinction. The former would be a bad investment and, taking the most favorable view, is only sentimental.
I am pretty sure that these are intended not for aliens, but for surviving descendents that may want to rebuild civilization one day.
Note that while “civilizations” (political constructs, rather) have risen and fallen, there has never ever in history been a case where there was no remaining population or neighboring barbarians left to pick up the pieces and start over. I am pretty confident that this is not going to change. Humans are a tough bunch, even while they are not yet spread across the solar system or galaxy.
Duncan Ivry said on December 12, 2011 at 14:42:
“I would like to insist on *not* making plans for the time after our extinction but on making plans for avoiding our extinction. The former would be a bad investment and, taking the most favorable view, is only sentimental.”
LJK replies:
Our civilization is still rich and stable enough to do both. And while I too would prefer to focus on the positive, I also realize that human nature and nature nature, both terrestrial and cosmic, tends to remain fallible. Thus my request, nay plea, for preserving our culture by various methods before it is too late. Future generations, even if they are just little ol’ historians, will thank us for thinking ahead.
Eniac said on December 12, 2011 at 23:58:
“[LJK said] such as the ones preserving seeds in the Arctic, and there have been proposals to place our knowledge in caves on the Moon.”
“I am pretty sure that these are intended not for aliens, but for surviving descendents that may want to rebuild civilization one day.”
LJK replies:
That is correct. I will assume ETI will find such a depository only if humanity is either extinct or no longer willing or able to conduct space travel.
Eniac then said:
“Note that while “civilizations” (political constructs, rather) have risen and fallen, there has never ever in history been a case where there was no remaining population or neighboring barbarians left to pick up the pieces and start over. I am pretty confident that this is not going to change. Humans are a tough bunch, even while they are not yet spread across the solar system or galaxy.”
LJK replies:
While I agree that humans are fairly resilient as a species overall (we have been on this planet in one form or another for about 6-7 million years now), it is our civilization which I wonder will survive another downturn.
When ancient Rome (at least the western half) pretty much collapsed in the Fifth Century CE, most other societies around the globe carried on as usual. Europe did go through a Dark Age, but most of the people could manage to carry on as farmers and hunters as they did before for generations. They even had a powerful religion and deity to focus on and get them through the hard times.
If things go wrong for us this time on planet Earth, it will likely affect the entire globe. As just one example, we still have more than enough nuclear weapons to bring civilization to a sudden halt for ages, along with producing enough radiation to render whole regions uninhabitable for centuries.
In the early years of the Cold War, it was a fantasy/propaganda of our military and political leaders that we might “get our hair mussed” in terms of tens of millions of people killed in an attack, but somehow the government would manage to recover, dust things off, and get the remaining society back in relatively short order. Two weeks was one overly optimistic estimate I have read about such a scenario.
As we have seen with several major disasters in just the last few years, the government at all levels cannot get its act together fast or efficiently enough in situations much less dire than a nuclear war; the only thing which saved them and us each time is that the events were thankfully localized and there was still plenty of remaining global and national civilization to more-or-less bail out the afflicted regions and people.
Unlike ancient Rome, we have a lot more to worry about than some barbarians at the gates. We now have the means to send us back to the Stone Age for generations, if not bring our species and many others on this planet to actual extinction. Even if we do not do ourselves in, there are various climate, biological, geological, and especially cosmic threats that could destroy us for which we have virtually no defenses against at present. Oh, we have talked about various ways of stopping an impending space rock from sending us the way of the dinosaurs, for example, but if a large enough planetoid or comet is aimed at Earth and we have anything less than years of advance notice, we may actually find ourselves in a resulting situation worse than a nuclear attack.
Sorry for all the doom and gloom, but it is foolish to think that just because we have some fancy technology and could once send people to the Moon that human civilization is invulnerable or somehow otherwise better and safer than the societies which came before us. If anything, our technological comforts have left many people essentially helpless if they suddenly found themselves without their cell phones and Kindles. How many of them will know how to properly hunt, fish, and farm? Even worse, depending on the disaster, unlike the folks in Medieval Europe, they may not be able to live off the land even if they do know such survival skills.
The fantasy I see is the perception that modern humans will somehow bounce back some day no matter how bad things get, even if most of the human population is wiped out. Among the worst such delusions, which I have addressed previously on Centauri Dreams, is that we would survive and defeat an assault by an advanced alien intelligence. Superior ETIs bent on taking us out of any galactic competition have several methods at their disposal for which we could do nothing at present.
So let us stop acting like we are the special beings of the Cosmos and that we can just keep carrying on like we have for centuries on this one ball of rock with no future consequences, or that we can ignore the rest of the Universe as if it did not really matter and Earth is somehow privileged and guarded. We need to start planning to protect and preserve our society now if we ever want to reach the stars one day. Because I honestly think if we let our civilization collapse that while we may get through it as a species, we may end up leaving the galaxy to others who appreciated their true places in the scheme of things and acted accordingly.
This is why a number of those early SETI pioneers said if they could ask an alien civilization any question, one of their first ones would be “How did you survive your technological adolesence?”
Ljk, I was just about to give up all hope after reading your comment of the 13th, when I suddenly noticed that parts of it seemed to make no sense. Ten thousand nuclear weapons could not raise levels of radioactivity to the extent you implied, and I doubt that level of “producing enough radiation to render whole regions uninhabitable for centuries” can be obtained by vaporising every nuclear power plant in the world. Perhaps you know of plans for America to salt all its weapons with thick layers of cobalt and build more powerful rockets to carry these much heavier warheads?
A more moderate and realistic hypothesis might be that the increased interconnectedness of an advancing society more that makes up for the increased power and complexity that it can and has applied to disaster avoidance. A less emotive and less political example of this is that a powerful solar flare hitting the earth could cause a break in civilised life now, yet just a couple of centuries ago we could not have suffered any such disruption.
ljk: “They even had a powerful religion and deity to focus on and get them through the hard times.”
Agreeing with many things you say, I can’t resist: It was religion which made the times of the people in Europe’s dark age much more harder than they had to be — religious wars, persecution of heretics, burning of witches, opression of ideas, etc.; and science succeeded *against* religion (why do I just now think of contemporary America?).
“How did you survive your technological adolesence?”
As far as I’m concerned, it’s not a *technological* adolesence which is dangerous per se. From most of what you say above, it’s a little bit suprising, that you just focus on this in your last statement. To my humble opinion, those early SETI pioneers are a little bit naive and not helpful sometimes.
A minor point: “Even worse, depending on the disaster … they may not be able to live off the land even if they do know such survival skills.”
In Europe, where I live, we have a highly productive agriculture. In most cases most people — e.g. unable-to-copy-with-life-mathematicians like me ;-) — won’t have to know how to properly hunt, fish, and farm — but as far as I’m concerned (and the rest of my family): general education helps a lot.
Rob Henry said on December 13, 2011 at 19:28:
“Ljk, I was just about to give up all hope after reading your comment of the 13th, when I suddenly noticed that parts of it seemed to make no sense. Ten thousand nuclear weapons could not raise levels of radioactivity to the extent you implied, and I doubt that level of “producing enough radiation to render whole regions uninhabitable for centuries” can be obtained by vaporising every nuclear power plant in the world. Perhaps you know of plans for America to salt all its weapons with thick layers of cobalt and build more powerful rockets to carry these much heavier warheads?”
LJK replies:
Yes, it was called Project Pluto, a.k.a. SLAM:
http://www.merkle.com/pluto/pluto.html
A cruise missile with a nuclear-powered ramjet for propulsion that could fly around in the sky for months without needing to refuel and strike multiple targets with hydrogen bombs when required. Pluto was so deadly that even its unshielded reactor was considered a viable weapon: After Pluto had delivered its payload of bombs, the missile could be flown back and forth over the USSR spraying radiation and radioactive exhaust debris. Even flying at Mach 3 so close to the ground (to avoid radar detection) was considered part of Pluto’s arsenal as the shock waves could deafen and kill anyone in its vicinity.
As you can see from the above linked article, the US military actually built several prototype engines in the early 1960s that worked in testing.
There was also a plan by the Soviets around the same time period to fill large nondescript ships with piles of radioactive material and sail them to enemy cities with ocean harbors to ignite the material when required, making for one heck of a radiation problem for that city.
Now about those commercial nuclear reactors: You don’t need to target them, though of course any self-respecting enemy with nuclear missiles would indeed be smart to do so, just let their safety features such as conventional generators lose power. When the reactors can no longer be contained properly – and this will happen in a nuclear war – the reactors will overheat and cause a nuclear meltdown, collapsing the containment buildings and spreading all that radiation over a wide area (not the whole world, I never said that even about a nuclear bomb explosion) which would kill all the life and make the area uninhabitable for centuries. And I don’t know about you, but I would not want to live at or near the remains of what used to be our major cities after a nuclear strike.
And don’t forget the nuclear winter scenario, where enough dust and debris from a full-scale nuclear war could be kicked into Earth’s atmosphere to cut off most sunlight for months, killing vast amounts of plants and crops and subsequently the animals (including us) that rely on them. Even if this scenario is not as bad as initially conceived, there will probably be enough ecological problems to make an already awful situation that much worse.
Rob Henry then said:
“A more moderate and realistic hypothesis might be that the increased interconnectedness of an advancing society more than makes up for the increased power and complexity that it can and has applied to disaster avoidance. A less emotive and less political example of this is that a powerful solar flare hitting the earth could cause a break in civilised life now, yet just a couple of centuries ago we could not have suffered any such disruption.”
LJK replies:
Wait – at first you are saying that the very complexity and advanced technology of our current civilization will compensate for most disasters that could threaten our way of life, then you give an example that shows how vulnerable our society actually is because of these very features. Am I confused?
Duncan Ivry said on December 13, 2011 at 20:29:
“ljk: “They even had a powerful religion and deity to focus on and get them through the hard times.”
“Agreeing with many things you say, I can’t resist: It was religion which made the times of the people in Europe’s dark age much more harder than they had to be — religious wars, persecution of heretics, burning of witches, opression of ideas, etc.; and science succeeded *against* religion (why do I just now think of contemporary America?).”
LJK replies:
Would any religion have been any less of a problem had Christianity not existed? Or perhaps I should say “Would another religion have been any better at preventing the natural and human-caused issues that would have cropped up as a result of the way the world and humans are?”
You will note that despite all the issues you mention with Christianity, millions of Europeans in the post-Roman Empire years clung faithfully to that religion for support in an existence that was already often difficult without the human-made threats. There are plenty of people to this very day and no doubt well into the future who will continue to seek guidance and salvation from the very deity that also supposedly made this existence the way it is and apparently allows all the misery that occurs for reasons that are often inscrutable to us little talking monkeys.
[Quoting LJK] “How did you survive your technological adolescence?”
Duncan Ivry replies:
“As far as I’m concerned, it’s not a *technological* adolesence which is dangerous per se. From most of what you say above, it’s a little bit suprising, that you just focus on this in your last statement. To my humble opinion, those early SETI pioneers are a little bit naive and not helpful sometimes.”
LJK replies:
I just brought up the above example as one of the prime questions the early SETI folks really wanted to know from an advanced alien species. I agree that some of these people were naïve, but when you are among the first in your field without decades of new information and hindsight to guide you, of course your ideas may look rather simplistic to future generations. Plus, when these pioneers were asking that very question, it was during the height of the Cold War when many (including myself) thought the end of the world in the form of a nuclear holocaust could happen at any moment. And with tens of thousands of nuclear bombs at the ready, it was hardly an idle concern.
Understand that many early SETI proponents seriously thought that the galaxy was humming with the chatter and data exchanges of superior societies throughout the stars and that we humans were just getting smart enough to be able to tune in. It was actually rather bold and daring of them to consider that other intelligences existed at all, especially when many of their peers considered the very idea of aliens to be either silly science fiction or outright sacrilege. They just got a bit carried away in their zeal by going to the other end of the spectrum. It took their decades of effort to at least determine that Earth at least may not be surrounded by noisy neighbors, or perhaps ones who are not interested in conversing with us.
Duncan Ivry then said:
“A minor point: “Even worse, depending on the disaster … they may not be able to live off the land even if they do know such survival skills.”
“In Europe, where I live, we have a highly productive agriculture. In most cases most people — e.g. unable-to-copy-with-life-mathematicians like me ;-) — won’t have to know how to properly hunt, fish, and farm — but as far as I’m concerned (and the rest of my family): general education helps a lot.”
LJK replies:
But just how much of that European agriculture will survive something like a nuclear war or global warming? I will also presume that the viable crops and other food that do remain will be the focus of deadly conflicts to procure.
That is why I said it may not do much good to know how to live off the land if there is nothing to live off of in the aftermath of a major disaster.
Oh would we just get our METI beacon built and delivered already before it is too late?! If nothing else, perhaps humanity can serve as an example to other civilizations how NOT to conduct one’s society.
It’s “cope with life” (and not “copy”) in my comment above. Arrg. Bear with me if my English is not satisfactory, please.
ljk: “Would any religion have been any less of a problem had Christianity not existed?” etc.
I said “It was religion …” — religion!. I did not talk about a special one. As far as I’m concerned, religion is just one of those “human-made threats”, and according to history, it just did not support an already difficult existence.
Regarding the early SETI pioneers: What you say above strengthens my statement, that those people sometimes were naive and not helpful.
Regarding survival of European agriculture, I said “In most cases most people …” — most! –, so, what you say is off the point.
I will not continue discussing this. Thank you.
Duncan Ivry said on December 14, 2011 at 16:40:
ljk: “Would any religion have been any less of a problem had Christianity not existed?” etc.
“I said “It was religion …” — religion!. I did not talk about a special one. As far as I’m concerned, religion is just one of those “human-made threats”, and according to history, it just did not support an already difficult existence.”
LJK replies:
And what was the dominant religion of Europe during the Middle Ages? You may feel how you wish about religion in general, but anyone with even a mild knowledge of Western history knows who ran that continent in that era. And it was not so black-and-white as you and others make religion’s mark on society out to be, but I have the feeling it will be a waste of time to explain further, to say nothing of this starting to get way off topic.
Duncan then says:
“Regarding the early SETI pioneers: What you say above strengthens my statement, that those people sometimes were naive and not helpful.”
I was not trying to debunk what you said about them. I was merely trying to explain a bit why they thought and acted as they did.
Duncan then says:
“Regarding survival of European agriculture, I said “In most cases most people …” — most! –, so, what you say is off the point.”
LJK replies:
Okay, then, let’s hope if Europe is engulfed in a nuclear war that the survivors can manage to maintain a sufficient food supply from what is left of the continent in the aftermath.
Duncan finally says:
“I will not continue discussing this. Thank you.”
LJK replies:
Probably a good idea all around.
Ljk said
“Wait – at first you are saying that the very complexity and advanced technology of our current civilization will compensate for most disasters that could threaten our way of life, then you give an example that shows how vulnerable our society actually is because of these very features. Am I confused?”
Rob replies
You missed my point. We must weigh the two very complex factors against each other to asses whether we are more or less vulnerable as technology advances, and much work has to be done before we should decide which is more likely to be true.
Well, Rob, let’s just hope we find the answer to that before it is too late. Heck of an “experiment” to be running, with billions of human lives and an entire planet as the stakes. And there may be no second chances.
I must confess that, like several others, I find the scenario somewhat implausible: A dying civilization with the resources to build a beacon that will last eons, that doesn’t spend the resources putting off dying a bit longer? I suppose that aliens, by definition, are alien, but we do require a peculiar combination of capabilities and motivations here.
I could see a religion building a beacon, but they likely wouldn’t wait for the funeral.
Going with it, maybe it’s not so much a “funeral” pyre, as a “this way to the exit” sign? Ultra-advanced civilization builds a doorway to Someplace Else, that’s so attractive they pick up and move there, (Maybe another universe where the laws of physics are better?) and leave behind a beacon so that anybody else who wants to can find and use the door?
Brett Bellmore said on December 18, 2011 at 7:41
“Going with it, maybe it’s not so much a “funeral” pyre, as a “this way to the exit” sign? Ultra-advanced civilization builds a doorway to Someplace Else, that’s so attractive they pick up and move there, (Maybe another universe where the laws of physics are better?) and leave behind a beacon so that anybody else who wants to can find and use the door?”
Judging from the behavior of the rich and powerful on this planet at least, one thing they tend not to do is share their wealth and power with others, unless they have a very good reason that strongly includes benefitting themselves. So why should advanced ETI be any different if it is survival of the fittest across the Universe?
I have similar qualms with the idea of ETI sharing the equivalent of the Galactic Encyclopedia, which Carl Sagan and Frank Drake among others assumed such intelligences might beam throughout the galaxy. Would they be so wonderfully altruistic like the Monolith ETI in Arthur C. Clarke’s 2001 series, helping along any intelligent species they find? Or would anyone who does give out such information desire something equally valuable in return?
This all assumes the lack of a Funeral Pyre reason, which various commenters in this thread have questioned.
This chapter from Xenology by Robert Frietas, first published in 1979, discusses the use of beacons for conducting METI here:
http://www.xenology.info/Xeno/24.2.5.htm
To quote:
“It is certainly possible that a beacon once trained on Sol, perhaps for years or even decades, has continued on in its signaling schedule to other stars and will not return to our direction for thousands of years hence. As Edward Fitzgerald once wrote: “The Moving Finger writes; and, having writ, moves on.”
and:
“Although several searches are still in progress at the present time, many xenologists are convinced that SETI searches are doomed to failure so long as they depend solely upon individual initiative and random funding. What is needed, they argue, is a major long-term commitment to SETI in which major radiotelescope equipment is dedicated in part or in whole to the search for communicative societies. To implement such systematic, far-reaching schemes, a new generation of ultrasensitive apparatuses may be required.”