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SETI in the Anthropocene

Have we, as some have argued, entered a new ‘age of humanity,’ the so-called Anthropocene? The notion is controversial in many quarters, but it addresses the growing concern about our human influence on the Earth and the nature of planetary change. David Grinspoon’s new book Earth in Human Hands (Grand Central Publishing, 2016) has much to say about the Anthropocene, but as anyone who has read the work of this canny scientist knows, he’s not one to let facile assumptions get by unquestioned.

For if the activity of humans is now emerging as an agent of geological change, then we are discussing our civilization in the same terms we talk about planetary forces like tectonic movement and the carbon cycle. This makes us major players whose effects we can begin to chart in terms of the effects of our technology on Earth’s living systems. If the Anthropocene is happening, it presents us not only with danger but the prospect of a long-term future. And its implications take in not just our movement into space but our search for other civilizations.

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Hence Grinspoon’s view that while we are leaving an unmistakable footprint on our planet’s living substrate, this is not something to be deplored as much as understood and put to good use, the theory being that living things have always shaped the world around them, in ways as profound as the Great Oxygenation Event of 2.5 billion years ago. Earth in Human Hands is rich in discussion of what it would be like to enter what Grinspoon calls the ‘mature Anthropocene,’ in which humans acting wisely and with long-term horizons learn to use technology to repair past damage and introduce a new era of planetary stability.

In this view, our current dilemma is that we are achieving global impact without any sense of global control. The analysis is filled with Grinspoon’s experience as an astrobiologist and it draws together themes that are at the heart of how we consider our own future and how we look at other civilizations. For make no mistake, when we examine SETI, we’re forced to address questions like the lifespan of a technological civilization. If such societies persist, how do they do it, and equally of interest, what sort of signature would they leave? Stanislaw Lem comes to mind, and Grinspoon quotes him from his Summa Technologiae:

We need to overcome the habit of considering outcomes of human activity as more imperfect than those of nature’s activity — understandable as such a habit may be at the current stage of development — if we are to talk about what is going to happen in a faraway future.

Are we not ourselves a part of the nature we study, and rather than deploring the fact, should we not be considering how to make our own contribution to the mindfulness that intelligent life brings to the universe? You may pick up a bit of Sagan in these themes, particularly the Sagan (and Shklovskii) of the 1966 masterwork Intelligent Life in the Universe. The connection is borne out by Grinspoon’s relationship with Sagan, who worked with the author’s father at Harvard and shaped his boyhood and early career. No wonder Sagan and Shklovskii’s influence on SETI play such a vital and entertaining role in his book.

A Third Route for SETI

A confluence of events marks the beginning of SETI, with Frank Drake’s early efforts at Project Ozma following swiftly after the famous “Searching for Interstellar Communications” paper by Giuseppe Cocconi and Philip Morrison. But I think you could say that the discipline put down its formative roots at two conferences, the first being the one Drake hosted at Green Bank in 1961, the second the First All-Union Conference on Extraterrestrial Civilizations and Interstellar Communication, which was held in 1964 at the Byurakan Astrophysical Observatory in Soviet Armenia. Between the two we see a foundational SETI defined.

Frank Drake’s famous equation emerged from Green Bank, a conference with only 11 attendees that took SETI out of the realm of theory and into observational science. At Byurakan, Iosif Shklovskii criticized the Cocconi and Morrison paper for being too restrictive — the authors, Shklovskii argued, assumed that extraterrestrial civilizations would be on approximately the same level as ourselves. Shklovskii believed that any civilizations we detected would be far more advanced technologically than ourselves, for “We are only infants as far as science and technology are concerned,” and technology’s growth is rapid.

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Grinspoon’s treatment of SETI is relaxed and knowledgeable, but it is the weaving of the anthropocene theme into SETI’s subsequent development that gives these chapters punch. For Nikolai Kardashev, then a young student of Shklovskii’s, was also at Byurakan to make the case for his three types of technological civilization, based on what he saw as a predictable and steady increase in the use of energy. Thus the categories most Centauri Dreams readers have come to be familiar with:

Type I: A civilization that can use all the energy resources of its own planet.

Type II: A civilization using all the energy resources available from its star. This is a civilization that has mastered its own stellar system and travels readily in space.

Type III: A civilization that can harness the energy of its entire galaxy. This is obviously an interstellar culture that moves freely between stars.

Image: Astrobiologist and author David Grinspoon, now a senior scientist at the Planetary Science Institute in Tucson.

We have often considered in these pages how advanced civilizations might present themselves to a distant observer; i.e., what kind of signature their engineering might leave in star systems and, indeed, in entire galaxies. Searches for Dyson spheres and odd stellar phenomena like the light curves of KIC 8462852 (Boyajian’s Star) continue to push the boundaries of radio and optical SETI. At a second conference in Byurakan, put together by Sagan and Shklovskii following the success of their book, the discussions of advanced technologies clustered around the Kardashev scale and its potential observables.

Radio and optical SETI, the first level of SETI, are complemented by a Dysonian SETI (level 2) that looks through our astronomical data for the signs of technological activity. But Grinspoon points out the key assumption of the Kardashev scale: That civilizations will inevitably increase their energy use in order to fuel a continuing expansion into the cosmos.

This is an idea of progress that is generally accepted — Grinspoon calls it the ‘inevitable expansion fallacy’ — but it is one that doesn’t take into account that key term (L in Drake’s equation) about the lifetime of a technological civilization. What if, in short, expanding in the Kardashev manner is the most likely way to end the growth of a culture?

A third level of SETI now emerges. You can see how Grinspoon is tying this back into the idea of an Anthropocene epoch on Earth. Let me quote him on this:

…it is reasonable to suppose that truly successful, long-lived species have all discarded the expansion imperative, and replaced it with an ethic of sustainability, of valuing longevity of expansion. If technological intelligence has a true and lasting form, one of its basic properties must be that it moves beyond the exponential expansion phase (characteristic of simple life in a petri dish or on a finite planet) before it hits the top of the S-curve and crashes. For us, achieving this kind of planetary intelligence will require critically examining our inherited biological habits and shedding those that have become liabilities.

And what exactly does a planetary intelligence involve? Grinspoon explains it as:

…thoughtful control over one’s self, escape from the mindless drives to multiply, to expand, to lay waste, kill, and drown in your own waste. Perhaps this is why we will not find what Shklovskii called ‘miracles,’ the highly visible works of vastly expanded super-advanced civilizations. Because advanced intelligences are not stupid.

At this point, we’ve stood Kardashev’s ideas on their head, for what Grinspoon is saying is that the kind of technological intelligence that lasts is one that has the ability to overcome its biological need for exponential growth. If this is the case, then we are confronted with the possibility that the more advanced a technological civilization becomes, the less likely we will be to distinguish it from natural phenomena. We may confront a cosmos rife with advanced civilizations whose work is so harmonized with their surroundings as to be invisible.

In earthly terms, the ‘mature Anthropocene’ is where we begin to move out of the era when the changes we make to our planet are beyond our comprehension, and into the era when we begin to consciously shape the Earth’s future, a time when, as Grinspoon writes:

…we fully incorporate our uniquely human powers of imagination, abstraction, and foresight into our role as an integral part of the planetary system. The mature Anthropocene differentiates conscious, purposeful global change from the inadvertent, random changes that have largely brought us to this point.

In SETI terms, consider the Anthropocene a metaphor for what can happen on other worlds. As we first confront the danger of technological over-reach in our environment and then learn to heal the wounds that limit sustainable growth, we may turn toward a balance that sustains our planetary ecology while ensuring the survival of our civilization. What Grinspoon calls the ‘Sapiezoic’ eon would be the long-lived stage of technological civilization that leads conceivably to immortality. Exponential expansion may simply be an evolutionary dead end, and the likelihood of finding civilizations that are learning this lesson the hard way is vanishingly small. They are simply not in existence long enough for us to see them.

Do we have a chance at detecting a civilization that operates according to the long-term model? Let’s talk about that tomorrow as we continue to look at this third route for SETI. We’ll also see that in Grinspoon’s view, expansion into space has a major role to play in the survival of long-haul civilizations. Developing a stable relationship with world-changing technologies is the key.

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  • ljk November 21, 2016, 14:12

    SETI Reconceived and Broadened; A Call for Community Proposals

    Posted on 2016-11-21

    by Marc Kaufman

    Earlier this summer, Natalie Cabrol, the director of the Carl Sagan Center of the SETI Institute, described a new direction for her organization in Astrobiology Magazine, and I wrote a Many World column about the changes to come.

    Cabrol’s Alien Mindscapes – Perspective on the Search for Extraterrestrial Intelligence” laid out a plan for the new approach to SETI that would take advantage of the goldmine of new exoplanet discoveries in the past decade, as well as the data from fast-advancing technologies. These fresh angles and masses of information come, she wrote, from the worlds of astronomy and astrophysics, as well as astrobiology and the biological, geological, environmental, cognitive, mathematical, social, and computational sciences.

    In her article, Cabrol said that a call would be coming for community input on how to develop of a Virtual Institute for SETI Research. Its primary goal, she said, would be to “understand how intelligent life interacts with its environment and communicates.”

    That call for white papers has now gone out in a release from SETI, which laid out the questions the organization is looking to address….

    Full article here:

    http://www.manyworlds.space/index.php/2016/11/21/seti-reconceived-and-broadened/

    To quote:

    White papers should be submitted in electronic form as PDF files to Dr. Nathalie Cabrol at ncabrol@seti.org. They should be no more than three pages in length, with a minimum 10-point font size. A figure can be included if of critical importance. It is anticipated that there will be an opportunity for interested respondents to present their contribution in person during a planned workshop in the summer of 2017.

    Notification of opportunities to present will be made after the white paper deadline of February 17, 2017, and those most responsive to this call will be published in the Astrobiology Journal. Questions related to this call should be addressed to SETI Institute President and CEO Bill Diamond at bdiamond@seti.org

  • john walker November 21, 2016, 15:09

    The characterizations of advanced civilizations such as that summarized above often appear too monolithic for my mind. I find it as unlikely that a single guiding principle will dominate the long term evolution of an advanced civilization as I find it hardly conceivable that such a civilization will long remain a homogenous entity. Without some unifying force be it biological or technical divergent pathways will inevitably emerge. A plethora of societal and (guided?)evolutionary preferences should lead to a wide range of civilizations. In permanent benevolent coexistance? ;)

    • DCM November 22, 2016, 5:08

      That’s right. We simply don’t know enough to consider such ideas as more than speculation likely equivalent to early versions of sci-fi from the 1700s and so when, for example, travelers found everything lost on the Earth scattered over the Moon.

  • Richard Prichard November 21, 2016, 16:41

    The subject of this article goes from a supposed human age to a political idea of sustainability. In the article, this idea is taken as a given without any analysis. Konstantin Tsiolkovsky, the father of Russian rocketry, noted that if if humanity does not leave its next, earth, it will die. Here is a better prediction: any technological species that remains on its planet will quickly die out.

    • Paul Gilster November 21, 2016, 17:45

      Grinspoon would agree. Quoting from my article: “…in Grinspoon’s view, expansion into space has a major role to play in the survival of long-haul civilizations. Developing a stable relationship with world-changing technologies is the key.”

      More on this tomorrow.

      • ljk November 22, 2016, 11:58

        Note that everyone in this thread is referring to humanity surviving as a *species*. We won’t be able to get everyone off Earth and many would not want to go anyway. So the reality is that a small number who colonize space will initially survive while those who are left back on the third rock from Sol may not be so lucky since population numbers will not decrease just by launching a relative handful of people to Mars.

        Humans can survive and thrive on Earth, but only if we make real efforts to reduce the future population numbers now by humane methods. Because if we keep breeding at the current rate things will get out of hand (I think we are already seeing such signs everywhere) and then either governments forced into martial law or nature itself will do what a civilized society could not and cull the herd with little to no mercy.

        Earth will survive humanity just as it has survived all sorts of detrimental events over its 4.6 billion year history. Whether humanity will survive is another matter. At least this time, unlike so many other species before us, we have a level of awareness and the means to control our destinies – if we collectively wake up in time.

        • Coacervate November 22, 2016, 16:19

          We are wonderful when we live by the cerebrum. But for the teeming masses its the “Jungle Book”.

          It is unethical to select for intellect (so I am told), so to what means must we resort to lift our game from the biological aspect.

        • Antonio November 22, 2016, 17:32

          “Because if we keep breeding at the current rate things will get out of hand (I think we are already seeing such signs everywhere)”

          Could you please at least search Wikipedia before saying so completely and hugely wrong statements? World birth rates have been continuously decreasing since at least 1950, when the UN started to collect data. Every 5 years, data was taken and every single 5-year period since 1950 birth rates have been decreasing. Currently, globaly, women have around 2.3 children in their lifetime. Below 2, we face extinction.

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

          • ljk November 23, 2016, 11:03

            It took all of human history for our species to reach one billion members in 1800. When the Arecibo Message was sent to the globular star cluster Messier 31 in 1974, they noted the number of humans on Earth at the time, around 4 billion:

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

            Just 42 years later, there are now 7.4 billion people all across the planet. Not exactly my idea of a decrease.

            Besides, this isn’t just about the raw numbers of people, it is also about the spread of urbanization and industrialization. Did you know that over 60 percent of Japan alone is urbanized? There may be a relative decrease in human birth rates in the more developed nations, but that is not the case in many other parts of the globe. We are still going to have over 9 billion people by 2050 and over 11 billion by 2100, barring some catastrophe.

            This useful site shows in literally graphic detail humanity’s spread across its home world:

            http://worldpopulationhistory.org/map/1/mercator/1/0/25/

            • DCM November 23, 2016, 18:06

              Prosperity usually brings a small stabilized population, as we’ve seen in wealthy European and in Asian countries like Japan. The solution to such a huge population is to enable other places to become as prosperous (not to crush their development under the guise of fighting climate change — which they hopefully won’t put up with).
              We may have to fight to preserve our own cultures, blasphemous as that may seem to some, but if we can manage not to let it be catastrophic population growth will slow after mid century.

            • Antonio November 23, 2016, 19:20

              Instead of admitting that your argument is completely false, you change the topic. OK…

            • Antonio November 23, 2016, 19:36

              And no, 60% of Japan is not urbanized. That is even more absurd that your previous false statement about enormous and out of control birth rates. If that were true, Japan would have more population than the entire world.

              • ljk November 28, 2016, 10:43

                Why should I admit to my argument being false when I don’t think it is? Because you demand it so?

                • Alex Tolley November 28, 2016, 13:45

                  It is hard to get meaningful data on this. japan’s land area is only partially inhabitable. So including this as land area that is potentially urban makes no sense. What we do know is that rural Japan, like Britain, is rapidly becoming urbanized, and that there are few new areas to build on. I would argue that Japan is indeed largely urbanized (its population is over 90% urban).

                  Anyone who has visited Hong Kong knows what extreme urbanization looks like. I believe the city-state of Singapore is similar. I certainly don’t want humans to be so close packed that we have the assumed density of “Stand on Zanzibar”.

                  Even an 11 billion population doesn’t get us anywhere a densely packed as some countries today.

        • Richard November 22, 2016, 19:52

          There’s the rub: If we collectively wake up in time. Seeing Musk’s colonial transports leaving the earth, however, may be the beginning of a wake up call. Also, if global trade is going to succeed, we need to create global organizations that prioritize massive infrastructure and environmental projects that begin employing more people. This in addition would promote global economic activity. The reason we have Trump in office is that there has been a failure of imagination and this in turn makes globalization a zero sum game.

          • ljk November 23, 2016, 11:32

            While public education in general has certainly been better than it ever has been before in human history, at least in terms of sheer numbers of people going to school and having relatively easy access to information and knowledge, it is also obvious that we still have a long way to go.

            Education cannot be just about learning basic data and rote lessons, either. It has to grab people on an emotional level as well, otherwise it will bear little resemblance to their everyday lives and be quickly abandoned.

            Our biggest issue is that most people are still largely tribal and parochial in their thinking. Yes, we know intellectually that we live on a planet called Earth, a big round(ish) rock hurtling through a vast and ancient Universe, but between their senses and the way society acts in general, we might as well be back in the days of Earth as a flat disc with the Sun, Moon and stars attached to some big overhead rotating sky dome.

            We need to expand the presence of our species, not just physically but culturally. Look at the US Presidential elections: Space was certainly not a top priority for the candidates or most of the voters, and that was true even in past elections where things were far less extreme by comparison. To anyone who knows even the most basic astronomy, does this not seem absurd for a species that does know it is living on a speck of cosmic dust yet still acts like it is the Center of Everything?

            While I have some issues with the following work, their overall goal is something I highly agree with:

            https://www.centauri-dreams.org/?p=23526

            At the risk of sounding all New Agey, if we do not expand our thinking and our presence cosmically, we will become just another failed species that once hailed from Earth, joining all the other extinct creatures in the fossil record. But getting everyone to realize this, not just the ivory tower crowd, is the key.

            If I had to show the general public two items to introduce them to these concepts to spark their interest, I would start with this:

            http://www.eamesoffice.com/the-work/powers-of-ten/

            and this:

            https://www.youtube.com/watch?v=Ln8UwPd1z20

            Ultimately, though, I think humanity is going to have to undergo a radical biological and technological transformation to truly “get” all this before our own civilization overwhelms our more base primitive, tribal selves. Natural biological evolution is just not fast enough to handle our rapid technological changes and expanding knowledge levels.

            Unless everyone wants to go back to the caves and trees, we need to adjust accordingly instead of hovering in this twilight between barbarism and true civilization. Otherwise it will be stagnation and decline at best or extinction at worst, and sooner than we think.

            • Alex Tolley November 23, 2016, 13:41

              Tribalism actually helps us. It is the basis for organizing groups which in turn allows for specialization and is a major driver of economic growth through productivity gains.

              Having a “cosmic” outlook is frankly a1st world problem. Much of the world is still living at the most basic levels of Maslow’s Hierarchy of Needs. This is true even in the US, as the current election has made quite clear.

              We don’t even have to evolve biologically, just culturally. There are plenty of signs that cultural change has occurred at a rapid pace.

              If one looks at what groups are trying to do to get a space civilization going, the most solid ideas are still based on economics and private wealth accumulation, rather than starry-eyed dreaming. The only other real reason for expansion into space is religious freedom, or more generally, a desire to avoid repression for your thoughts and beliefs.

              How one views civilization depends on whether you view the glass as half empty or half full. No guarantees that civilization will succeed on Earthby doing the right thing, but I suggest that working towards that and not throwing up one’s hands in despair in the best way to go. Any future space civilization will be populated by those born in space. The vast bulk of the population on Earth remain on Earth, as will their descendants. Their needs remain paramount, for now.

              • ljk November 23, 2016, 16:58

                This is why I also suspect that humans are not the final word on the evolution of intelligence from Earth. They have evolved the knowledge and the means to view and reach the wider picture, but ancient biological programming may undermine such goals. Another species will either truly succeed at living in harmony with the planet, or they will leave altogether.

                Failing this, then there will become two human cultures: One that stays on Earth and the other that doesn’t. They will undoubtedly interact with each other for a while, but eventually the ones who head off into the galaxy will lose both contact and interest in keeping in touch. Hmm, maybe Asimov’s Foundation stories of the legendary lost planet Earth are not so implausible after all.

  • Charlie November 21, 2016, 16:51

    This is certainly one of the more important postings added been made on this website.
    Obviously, the first and foremost problem will be how to provide food and fresh water to the burgeoning numbers of people that are to be born in even the next decade or so. People in poor countries and people who are yet to be born are going to need education, jobs, healthcare, in short, any number of basic aspects of life as they are to have a decent type of existence.
    These people are going to burn more fossil fuels, which will increase global warming and all the other aspects that have now been shown to be so deleterious.
    I would suggest that we immediately enact some kind of family reduction program in which two individuals who marry have one child and only one child to their name and family. In one generation, in theory, this will cause the population to fall by 50 percent, which is a good start, but it should be cut down Middle East by another 50 percent. If everyone on earth is to have a decent lifestyle. In addition, a explosive population of human growth is going to put almost unbearable pressure on the ecosystem and animal systems and plant systems that are now in a fragile and perilous state at this point. I’m afraid they’re going to the stars is not going in effect to reduce this almost unlimited growth and in fact the explosive population growth is enough to actually make space travel even less possible simply because of the fact that there’s going to be a competition of resources and something as esoterica space travel is going to be at the very bottom of everyone’s wish list.

  • Dusanmal November 21, 2016, 17:12

    I find it peculiar that I agree so much on some aspects of Anthropocene with Dr Grinspoon but on other aspects of it we couldn’t be more fundamentally opposed… I’ll address the latter, summarized in his quote:
    “…it is reasonable to suppose that truly successful, long-lived species have all discarded the expansion imperative, and replaced it with an ethic of sustainability,”
    I’d counter it with Earthly example of differing strategies of Poly-/Micro-nesian people and that of Easter Island civilization. Biological expansion is not by definition exponential. However, biological expansion of some kind is not just evolutionary dictate but the fundamental property of life. It is not optional. Trying to “cheat” it with “ethics” can have one and only one outcome: Easter Island type of the outcome. Poly/Micro-nesia example shows harmony of biological dictate and society: resources of the current location are used to sustain population appropriate for that area AND “as soon as possible” spread of the species, along with useful “resource species” (coconuts, pigs,…) to new and unused habitats, many of which are converted to usability from their natural barren state.
    In the example of Earth, P/M strategy would be to now, as soon as we possibly can, start any (and all) theoretically plausible strategies to terraform Mars and actively plan permanent colonies there to the same purpose. Longer we wait, more we restrict ourselves with “ethics” for preservation – less chance for long term survival and needed expansion, more chance of complete collapse at the smallest perturbation.
    As for not seeing Alien civilizations-I see the main problem being us looking for other us while Alien life , including intelligent Alien life is certainly most likely not to be “other us” but fundamentally alien in every aspect.

  • Carson November 21, 2016, 18:00

    I’ve always found the idea of finding graveyard civilizations almost as interesting as active current life. With the more we learn it seems the more we have against us in terms of finding life. If live or civilizations rarely leave their home planet it would seem Red Giants would swallow up all evidence of fauna or civilizations. This would be a tragedy. The Universe is sure making it difficult to find and correspond with other life.

  • Joe November 21, 2016, 19:10

    I disagree with Grinspoon’s idea that the more advanced a technological civilization becomes, the less likely we will be to distinguish it from natural phenomena. I think the same maturity that enables an advanced civilization to choose sustainability over reckless expansion will also generate a desire to make themselves known. This is because a basic trait of intelligence is curiosity. Like us, an advanced civilization will be curious to know how common or rare they are in the galaxy. Such a civilization will by definition have the energy resources to deliberately broadcast into deep space to see if anyone is listening.

    Given the vast distances between stars, and the impossibility of faster than light travel, such a civilization will likely conclude that the possibility of such a broadcast causing them any harm are virtually nil. (No bug eyed aliens are going to show up in FTL starships to attack them.)

    Instead, this type of communications project will give an advanced civilization a chance to self-actualize. In addition to choosing sustainability, the maturity inherent in this type of civilization will give them the ability to plan and execute projects such as this one that may take centuries to yield results. Even if unanswered, such a signal will serve as a sort of galactic Ozymandias announcing “Here we are, behold our accomplishments.”

    Perhaps Earth will detect such a signal someday and we’ll have the maturity and ability to respond.

    • Daniel Suggs November 21, 2016, 21:38

      “Given the vast distances between stars, and the impossibility of faster than light travel, such a civilization will likely conclude that the possibility of such a broadcast causing them any harm are virtually nil. (No bug eyed aliens are going to show up in FTL starships to attack them.)”

      Seems to me that it would be very foolish for a civilization to flag their presence, based on their assumption of ‘the impossibility of faster than light travel’. It may not be impossible for our level of technology, but 500 years from now, who knows? And we must assume that there are civilizations millions of years more advanced than us, so what might they be able to do? Based on what we think we know now, should we yell to the stars, “Here we are, but you can’t touch us!”? Sounds like suicide to me.

      • Richard Flapper November 22, 2016, 7:39

        Agreed and applying a Darwinian adapt or die pattern rather fits the current “silence” quite well (Silence between quotes because it of course could quite well be we are not yet able to detect civilisations across interstellar distances). If any civilisation becomes too noisy it attracts unwanted attention and gets eliminated. Any remaining civilisation is either really silent or has learned from its mistakes and has gotten silent. I’ve always regarded the Berserker hypothesis as quite well fitting the observations.

        • ljk November 22, 2016, 13:58

          This assumes that ETI are aware of us and look upon all alien species only in terms of how they can exploit, conquer, and/or destroy them.

          How about that while it is certainly not impossible that smart technological beings could cross the stars, even if it means via slow methods such as with a WorldShip, that such efforts are not simple even for advanced societies.

          If it is resources they want, would it not make more sense to get those things locally? We already have evidence of star systems full of comet and presumably planetoid belts, along with actual whole worlds. If nearly every star system in the Milky Way galaxy has a collection of worlds, then they don’t all need to focus on Earth as they so often seem to do in our SF literature and films.

          And of course many humans continue to assume alien beings will have human motives and desires, such as wanting to do SETI when they get smart enough (whatever that is exactly) or take themselves in person across vast gulfs of empty space just to say hi or steal all our water, especially when comets are plentiful, far less massive than Earth, and have no known natives who might object.

          • Daniel Suggs November 24, 2016, 23:14

            I would completely agree with you, except for one thing: What if there is another reason that we can’t even understand? Should we bet our existence when there is any doubt at all?

            Also, what if we were dealing with an ancient galaxy spanning civilization which has seen thousands of new species come along and try to elbow in for a share. They might have decided it is just more cost effective to wipe out anyone who might give them competition in the future. As soon as they spot signs of technology, they send in the troops to return the upstarts to the stone age. Much easier than waiting for us to come to them.

            • ljk November 28, 2016, 11:11

              You make salient points. The “problem” is that we are not hidden from the rest of the galaxy. There is the issue of electromagnetic leakage, which has created a bubble of signals about 200 light years across. Small compared to the Milky Way with its 400 billion star systems spanning 100,000 light years, but it is still an attention-getter for those able to detect such signals.

              Earth has also let the Universe know it is covered with life by its mere presence. Terrestrial organisms produce various natural signatures that to anyone with the brains and ability will see this as a sure sign of life on our planet.

              The other issue is trying to get everyone to cooperate when it comes to METI, the deliberate messaging to the stars. Breakthrough Listen seems to be trying to get some kind of consensus on the matter, but there are plenty of groups that see no real issues with doing METI: This includes the European Space Agency (ESA), which has done several METI in just the last few years. When I emailed them about these actions, asking if they had consulted with astronomers and scientists, I was told – and I quote – “Don’t worry about it.”

              So we can hope anyone who can ply the stars is nice or at least has watched Star Trek and practices the Prime Directive, but the Universe has shown how seldom it follows human desires and wishes and whether we are actually ready for such a cultural shift. This likely includes alien contact. The best we can do for now is be as ready and aware as possible. The idea of aliens is embedded in most human cultures even if it is no more than science fiction, so that helps, but we could be doing so much more. After all, we do know just how big and ancient the Universe is, so we need to stop pretending we are still the Special Center of All Creation or we may pay a big price for such willful cultural ignorance.

            • ljk November 28, 2016, 11:30

              Are our views on ETI really just a reflection on what Western cultures did to others doing the colonial period?

              http://www.theatlantic.com/entertainment/archive/2014/04/why-sci-fi-keeps-imagining-the-enslavement-of-white-people/361173/

              Just more reasons why we need to really ramp up SETI.

      • Joe November 23, 2016, 15:41

        Not a single theory for accomplishing FTL travel holds up under close scrutiny. There is nothing to suggest this will change in the future, even when we solve the mysteries of dark matter, dark energy, quantum entanglement, etc. But let’s assume for the sake of argument that FTL is possible and some alien race detects a signal from Earth and decides to pay us a visit. One of the paradoxes of general relativity is that if the aliens can travel faster than light, they will likely arrive BEFORE we send the signal. This would screw up causality. Which is just another reason why FTL travel is not possible. We should not let irrational fear of interstellar contact limit our SETI efforts. The whole point of SETI is to find some aliens, not hide from them.

  • DJ Kaplan November 21, 2016, 20:25

    I agree that we have entered a new age, in which humanity is beginning to radically alter the face of the earth. Certainly, thinking about this, can help us to envision what signature that other beings might leave on their own worlds.

    For me, it seems a little humorous to see someone billed as an expert in extraterrestrial life, when no such life has been found yet.

  • Patrick November 21, 2016, 23:03
  • Alex Tolley November 21, 2016, 23:52

    1. fast expanding and dying civilizations should be leaving all sorts of archaeological detritus in the galaxy. Perhaps that is what SETI might want to focus on.

    2. There is no reason to preclude slow expansion that lasts millions of years, rather than our fast rate of economic growth.

    3. There is no a priori reason to assume that advanced civilizations will become “invisible” as they learn to sustain their worlds. They may decide to abandon planetary bodies as natural reserves, living in extra-planetary cities with perfectly visible presences.

    4. Advanced civilizations may be machine based and either be like civilizations in (3) above, or transform their worlds to purely artificial ones.

    5. Civilizations may become transcendent, occupying the universe as immaterial entities in our space or in different ones beyond our current knowledge.

    So I see lots of potential outcomes, and any combination might have been tried by past and present civilizations. The galaxy could be littered with the equivalent of the many cities that stood on the site of Troy, quiet, mature civilizations living in vastly extended biospheres in their home systems, or living in artificial habitats and worlds as machine entities, to civilizations that have either retreated to a no-growth simplicity or a restricted “enclosure” like Clarke’s city of Diaspar.

    Each of these scenarios offers different approaches to SETI, some easier than others to detect. As always, going for the low hanging fruit is the best way to proceed.

    • hiro November 22, 2016, 20:55

      #5 might be possible, a clue/hint exists in a Spain gravitation seminar around 90-92, but it became a dead end when I failed to find the paper which contains some important information.

  • Coacervate November 22, 2016, 3:56

    Empires come and go while civilisation remains. Even nuclear conflagration can not eradicate all of humanity. Can it? I’m asking. Can we even answer that? Else we are virtually “On the Beach”

    • ljk November 22, 2016, 11:39

      No, not even if humanity still had all the nuclear weapons we did back at their peak numbers in 1989, when the USA and USSR between them had approximately 55,000 such devices, could the human race be rendered wholly extinct as a physical entity.

      However, what populations would be left and the conditions the “survivors” would be stuck with make the idea that they would return to a civilized state any time soon questionable. Unlike during the Middle Ages after the collapse of the Western Roman Empire, where most people at least knew how to farm and hunt and the environment was fairly pristine, current humanity as a rule has become quite dependent on their fancy technology and live a life of comfort even ancient kings did not enjoy. We are so confident in our own superiority that we even entertain ourselves with programs and films about post-apocalyptic worlds from the safety and comfort of our living rooms and cinemas.

      Then add in the long-term devastation to the environment thanks to all the radiation and the onset of nuclear winter and the only populations I can imagine even having a chance to survive and one day thrive again might be the ones who planned ahead and set up shop underground ala the end scene in Dr. Strangelove. That is assuming such plans have already been implemented, which I question as people became pretty lax after the collapse of the Soviet Union in 1991 and the assumption that the Cold War was then over.

      Those who did survive such a catastrophe would have to be tough and even brutal by necessity. Perhaps once again we would have to count on a few monks holed up in some monasteries preserving what was left of the previous civilization as best they could ala A Canticle for Leibowitz:

      https://public.wsu.edu/~brians/science_fiction/canticle.html

      http://www.newyorker.com/books/page-turner/science-fiction-classic-still-smolders

      Here is some data on what would happen during and after a large-scale nuclear attack:

      http://www.nucleardarkness.org/warconsequences/hundredfiftytonessmoke/

      In the 1950s, many thought that a nuclear war would be winnable, including the so-called experts. Remember the line in Dr. Strangelove about there being no more than ten to twenty million dead, tops, depending upon the breaks? That came from real Cold War studies that considered such numbers “acceptable” losses. This is why Stanley Kubrick turned his incredible 1964 film from a very serious story into a dark satire, the whole concept being just so devastating it reached Sartre levels of absurdity.

      Rod Serling was among the first to publicly declare that nuclear war was not only unwinnable, but that even a so-called limited skirmish could mean the end of civilization and even the whole species. Watch all the episodes of The Twilight Zone which focus on nuclear war: None of them end with brave survivors slowly rebuilding society at the end. Instead we can end up with one lone bookworm who just wants to read and breaks his only pair of glasses in the rubble.

      Note that Serling was also involved in writing the first draft of the classic 1968 film Planet of the Apes, which was about other primates coming to terrestrial dominance after humanity nuked itself into a primitive state.

      Another terrible aspect of nuclear war which was not really considered or realized until the 1980s was the concept of nuclear winter, the long-term effects of detonating nuclear bombs all over Earth. Sure, the radiation levels might die down in a few weeks after an attack, but that would just be the beginning of the devastation, not the end. See here:

      http://www.e-reading.club/bookreader.php/148584/Sagan_-_The_Nuclear_Winter___The_World_After_Nuclear_War.pdf

      https://www.youtube.com/watch?v=HijgaqjJ8AI

      So, in conclusion, would humanity survive a nuclear war? As individuals, yes, there would be physical survivors even after a big attack: With over 7 billion humans spread across the globe, it would be very hard to kill them all even with thousands of nuclear bombs.

      But would civilization survive and even one day return? That answer is more than a little problematical. Maybe it’s just better if we don’t nuke each other over some political or religious ideologies that will not matter one second past the first detonation. Besides, there are plenty of forces within and off Earth that could just as easily take us out and with even more devastating consequences than a whole slew of nuclear warheads.

      • Coacervate November 22, 2016, 16:28

        Thanks for that detailed answer. and all your comments. Brilliant stuff.

        I read Sagan and Shklovskii as a teen along with WS Sullivan and anything else I could lay hands on in that vein.

        Granted that nuclear war would be a set back…I would argue that it presents the kind of selective pressure needed to elicit the kinds of behaviours that are sorely lacking in present civilization. Yes it would take a few (hundred?) years to get things rolling again but on the cosmic timescales we are considering is that really a big deal? Looking back 1000 years out, would “we” think it worth the trouble?

        I just ordered Canticle, ta

  • DCM November 22, 2016, 5:10

    Anthropocene? Yes, we do rank up there almost next to worms, bacteria, and algae as elements in the biosphere.

  • ljk November 22, 2016, 10:49

    If humanity suddenly went extinct now, most everything we left behind on Earth would either be gone or buried within centuries:

    http://www.dailymotion.com/video/x1g5g09_life-after-people-episode-1-life-after-people-discovery-history-science-documentary_tv

    Our artifacts left in space are another matter. They could survive for millions of years or more. The twin Voyager Interstellar Records are conservatively expected to survive in deep space for at least one billion years, and that is just the side facing outward from the space probe.

    • DCM November 22, 2016, 17:57

      Our concern here and now isn’t that we may become extinct at some time or that if we colonize, say, Mars politics and crap will continue on Earth (as it did in Europe after masses of its inhabitants occupied America and Australia).
      Our concern is carrying out that and other colonizations, and not just with people but with various plants and animals.

  • Cambias November 22, 2016, 11:36

    It’s hard to imagine anything which could actually exterminate humanity. Seriously: we handled the Ice Age without metal tools. The Black Death barely slowed us down. At the end of a century full of titanic wars and genocidal atrocities, we’re richer and more numerous than ever. Even nuclear war would mess up the combatant powers, but who’s going to lob expensive missiles at, say, Paraguay or Angola?

    Nor is it easy to imagine something which could reliably and inevitably exterminate non-human civilizations elsewhere in the Galaxy: perhaps the fanatical Vegan Deep Green Party actually managed to wipe out their species with nanotech synthetic plagues, but the Fornaxians never had a Green Party, so they can go on to colonize the Milky Way.

    My personal suspicion (I’ve voiced it before) is that something we’ve identified as a natural phenomenon is actually the work of technological civilizations — maybe there’s a good practical reason why civilizations take to parking gas giants in close orbits around main-sequence stars, or for arranging all the stars in a galaxy into spiral patterns.

    • ljk November 22, 2016, 14:49

      Or the stars themselves are alive and aware:

      https://www.centauri-dreams.org/?p=33995

      We may have a very narrow view of what constitutes life and intelligence, even if isn’t what I linked to above.

    • hiro November 22, 2016, 20:51

      That event around 250M years ago might be the Ag bullet.

  • David November 22, 2016, 11:49

    I always thought that one explanation for the underlying premise of the movie Avatar was exactly this. A civilisation that had engineered a utopia together with immortality uploads into a global database. One way to look at the ecology of the planet was as a self sustaining civilisation where its technology was embedded into biology.

    But that’s giving way too much credit to James Cameron.

  • ljk November 22, 2016, 12:12

    Quoting from the main article:

    “At Byurakan, Iosif Shklovskii criticized the Cocconi and Morrison paper for being too restrictive — the authors, Shklovskii argued, assumed that extraterrestrial civilizations would be on approximately the same level as ourselves. Shklovskii believed that any civilizations we detected would be far more advanced technologically than ourselves, for “We are only infants as far as science and technology are concerned,” and technology’s growth is rapid.”

    Mark A. Sheridan’s 2009 work, SETI: A Critical History: How the Search for Extraterrestrial Intelligence Became Disconnected from New Ideas About Extraterrestrials, showcases how from the start of the modern SETI era, the US set up a search strategy that basically had scientists looking for versions of ourselves due to the predominant use of radio telescopes. Other parties, especially the Soviet thinkers, found this strategy not only to be limited and perhaps futile, but even absurd in light of the fact that alien beings would be, you know, *alien*.

    The entire book, which I consider to be a must read for anyone who wants the real, in-depth history of SETI, is online here:

    http://www.daviddarling.info/encyclopedia/S/SETI_critical_history_cover.html

    The Polish science fiction author Stanislaw Lem also took a non-Western and decidedly more ambiguous view of ETI in many of his novels, with his two most prominent ones being Solaris and His Master’s Voice. He also had similar things to say in his prophetic non-fiction work, Summa Technologiae:

    https://www.upress.umn.edu/book-division/books/summa-technologiae

    https://muse.jhu.edu/book/24903

  • DJ Kaplan November 22, 2016, 13:16

    Could TYC 8241 2652 be a case of “exo-archaeology”?
    http://www.daviddarling.info/encyclopedia/T/TYC_8241_2652.html

  • ljk November 22, 2016, 14:39

    Maybe Titan is the next answer if humans are still biological by the time we can colonize it:

    http://www.thespacereview.com/article/3106/1

    To quote Thomas Matula in the Comments section of the above article:

    However, the authors are on the right track, Titan and the entire Saturn system is especially attractive because of the richness of the resources available. Titan is rich in hydrocarbons, the rings of Saturn are made of easily accessible water, He3 from the atmosphere of Saturn and 60 plus other moons full of resources for space settlers.

    The great thing about Elon Musk’s ITS is that it does allows missions beyond Mars.

  • George King November 22, 2016, 17:04

    Have always thought that the Kardashev scale said more about 1960’s Earth than necessarily extraterrestrial civilizations. Makes me think of muscle cars, ever larger rockets, and other reflections of those times.

    Nice to see someone making the point in a scholarly way.

    • Cambias November 23, 2016, 9:00

      A K-III civilization has muscle cars with the energy output of an ENTIRE PLANET!

  • Charlie November 22, 2016, 19:44

    “… calls the ‘mature Anthropocene,’ in which humans acting wisely and with long-term horizons learn to use technology to repair past damage and introduce a new era of planetary stability”
    forgive me for my cynicism, but the last thing I believe is that humanity will act in a manner which exhibit humility and concern for the world around it. We as seeing that so much of what goes on in the world consist of greed, avarice, exploitation and a me first type of attitude. At least that’s been my exposure within the last several decades that I have inhabited this planet.

    Certainly it is admirable to have traits which shows concern for others. But let’s get more down to earth here. I’m afraid that within the humanity and within the fabric of life itself that there is a survival mechanism, which always tends to try to obtain one upmanship at the expense of others, and that would go even at the expense of our own planet.
    I wouldn’t be able to say, of course, with any certainty, but I have a feeling that we are unlikely anytime soon to find a Earth 2 anytime soon, and anywhere near this planet, which is in its own midlife type of crisis.
    That’s why I stress that the population needs to be drastically controlled so that we don’t stress our life-support system to the breaking point.
    I know that there are people out there who recoil at the idea that anyone since should suggest that the populations should be in any way diminished, because it supposedly smacks of some type of political incorrectness.
    However, I know this, and this is a absolute fact:
    and that is – if you DON’T overdo something you don’t have to worry about it having a breakdown, and that is true whether you’re talking about a piece of machinery, your health, or what have you. What you don’t test the limits on you don’t have to worry about you finding out that you’ve exceeded the limits. And that’s the most important lesson that I think anyone could ever learn; DON’T BREAK THE MACHINERY WHEN YOU HAVE A DEPENDENCY UPON IT !!

    • Alex Tolley November 22, 2016, 22:11

      The western world is far less destructive than it used to be. Unfortunately we also have more capabilities to be destructive and some nations and nation-sized corporations seem almost sociopathic in their need for growth and profit. Nevertheless, unless enlightenment thinking is just a short “flash in the pan”, I am optimistic that many parts of the globe will become far more careful in their stewardship of the planet. The world’s resources will not be treated as a “commons” but rather as a resource to be used sustainably. After all, most nations agreed to COP21 to reduce carbon emissions, and even though our POTUS-elect says he is going to tear it up, China, Europe and other nations will stand by their decision. They may even treat the US as a rogue nation and exact some for of sanctions.

    • Ron S November 22, 2016, 22:17

      “the population needs to be drastically controlled”

      What’s up with your idee fixee? If you insist on this path I expect that you start with yourself. Do you have children? Have you had yourself neutered? When you’ve done that you are perhaps ready to preach at others.

      FYI, the proven best ways to reduce reproduction in a population is to lift them out of poverty and educate the women. It works very well, just as we see in the developed world and developing world. Contribute to one of these and you are doing your part. Get to it. Shouting and fretting aren’t action.

  • Coacervate November 22, 2016, 22:41

    However, I know this, and this is a absolute fact:
    and that is – if you DON’T overdo something you don’t have to worry about it having a breakdown, and that is true whether you’re talking about a piece of machinery, your health, or what have you.

    How do you know that? I wish you would tell my Jinma 140 that

  • Coacervate November 22, 2016, 22:46

    Imagine finding a stone-age tribe and telling them about NYC… “Ur not know about flying machine but if rich as you say they must have much FLINT”

    heh

  • Coacervate November 23, 2016, 19:13

    It is just my gut feel but I’ve read the wiki page on world population, some of the WHO and FAO pages and just in general there is a kind of push to present population growth as levelling off around 10 billion…now its up to 11 i guess.

    Its kind of a PC thing to insist that the population curve is not a problem. But I think we are already way over populated at 7 billion…just a moment…just a moment…make that 8 billion.

    Isn’t the question really: How many people is the right number for Earth? Or range of people?

    • ljk December 20, 2016, 11:22

      In the novel version of the 1972 film Soylent Green titled Make Room! Make Room! by Harry Harrison, the world of the year 2000 (the film took place in 2022), the global human population was 7 billion. In the film there were 40 million people in New York City.

      The so-called experts once said that human numbers would peak at 9 billion in 2050. Now they say they will reach 11 billion by 2100. It took millions of years for humans to reach the one billion mark in 1800. Technological civilization, with its medicines and various sanitation systems, has allowed humanity to breed faster than its numbers can die off.

      When the Arecibo Message was sent towards Messier 13 in 1974, there were 4 billion humans on Earth as recorded in the transmission. Just 42 years later, we have 3.5 billion more people on the planet. Will key and still humane steps be taken to cut back on overpopulation, or will we wait until nature and martial law do the job for us, and with little to no regards for human rights?

      • Alex Tolley December 20, 2016, 12:31

        On a lighter pre-Xmas note, this rapid growth of the human population reminds me of the ending of Clarke’s short story, Rescue Party.

        “Something tells me they’ll be a very determined people,” he added. “We had better be polite to them. After all, we only outnumber them about a thousand million to one.”
        Rugon laughed at his captain’s little joke.
        Twenty years afterward, the remark didn’t seem funny.

  • Charlie November 24, 2016, 0:12

    The questions have been raised above that people have become more “enlightened” and therefore as a result of that everything is going to be extremely hunky-dory. The only problem of course is that it really isn’t true, and the fact that we now have perhaps tens of billions of tons of garbage that we don’t know how to dispose of, without any adequate means of making sufficient recovery of precious metals and common metals (at least not to the extent where we don’t have to mine additional mineral resources) is enough to make me think, along with many, many other things that we have not achieved a very good stewardship of this planet.
    And don’t forget, that this is just within the developed nations of the world – the underdeveloped nations are attempting to drastically bring their standards of living up to that of the developed world, and when they do so it will be even more of a stressor upon the planet and its populations. Unless one does not have the basic concept of matter and energy you can see that the course that the world is on is not a sustainable one and it is a direct reflection of the fact that the population has now reached a tipping point that in the years to come could conceivably be enough to destabilize the entire world.
    It’s just common sense, that’s all it really amounts to, that the idea is not to attempt to overdo anything, but rather to try to find a balance at a much lower level of population than what we are currently seeing. Why try to overdo the situation? Why not attempt to control and ameliorate what could be a ruinous calamity? This was the point that I was trying to make previously, but it seems that somebody or other appeared to take offense when no offense was meant but really just trying to point out what I think is obvious and is in front of our eyes. That’s the underlying theme that I was attempting to put across in previous posts.

    • Alex Tolley November 24, 2016, 12:14

      Economies are becoming increasingly “lightweight”, less energy and materials intensive. Certainly, if all the planet was levelled up to US or even EU standards today, the planet would be seriously overburdened. But today’s economy mix won’t be the same as tomorrow’s. Even in the US, car buying has peaked and will continue to decline as population shifts to cities continues. When once we bought lots of kit, now small electronics and digital media predominate. Industry is shifting profits into nano-scale technology. The Chines are still building like mad to contain their still rising population, but even this is peaking, with energy intensive steel and concrete manufacture in decline. So yes, in the medium term the planet is going to be increasingly stressed, but, if we can control AGW, sufficiently, the global economy may well be able to adjust to a high standard of living for 10 billion people. What I don’t see is how African nations adjust to a low population growth without increasing mortality or reducing birth rates as education and economic opportunities are improved.

  • Eniac November 28, 2016, 23:52

    Sustainability and growth are only in conflict if there is no new territory to expand into. Expansion into new territory enhances sustainability, so there is no economic reason to suppress it.

    Also, no star-faring species could possibly have the discipline and totalitarian control to stop all of its members from colonizing uninhabited territory, ever.

  • ljk December 7, 2016, 10:19

    https://arxiv.org/abs/1611.02586

    Can the periodic spectral modulations of the 236 SETI candidate Sloan Survey stars be due to Dark Matter effects?

    Fabrizio Tamburini (1,2), Ignazio Licata (3,4,5) ((1) ZKM – Zentrum für Kunst und Medientechnologie, (2) MSC – bw, Stuttgart, (3) Institute for Scientific Methodology (ISEM) Palermo Italy, (4) School of Advanced International Studies on Theoretical and Nonlinear Methodologies of Physics, (5) International Institute for Applicable Mathematics and Information Sciences (IIAMIS), B.M. Birla Science Centre)

    (Submitted on 8 Nov 2016 (v1), last revised 9 Nov 2016 (this version, v2))

    The search for dark matter (DM) is one of the most active and challenging areas of current research. Among the several effects of DM expected to be observable in astrophysics, very rapid stellar oscillations are expected to occur when certain types of stars accrete a particular type of DM in their interiors with well-defined frequencies f that depend on the mass of the DM field quanta.

    If the recent discovery of peculiar periodic spectral modulations in a small fraction of solar type stars from 2.5 million spectra in the Sloan Digital Sky Survey is not due to experimental, data reduction or other types of errors, nor, as it has been claimed, effects of SETI-like signals in the optical band we conjecture, instead, that this could be the first indirect evidence of axion-like ultralight DM fields effects in main sequence stars with radiative nucleus.

    The non observed oscillations in higher stellar spectral classes might be due to the impossibility of starting an oscillatory regime because of the continuous mixing of ordinary and dark matter in their convective nuclei. From the frequency range between 0.6077 and 0.6070 THz, so far obtained from these data, one obtains an axion mass that agrees with the recent results of QCD calculations.

    Comments: 5 pages 2 figures

    Subjects: Solar and Stellar Astrophysics (astro-ph.SR); General Relativity and Quantum Cosmology (gr-qc)

    Cite as: arXiv:1611.02586 [astro-ph.SR]
    (or arXiv:1611.02586v2 [astro-ph.SR] for this version)

    Submission history

    From: Fabrizio Tamburini [view email]

    [v1] Tue, 8 Nov 2016 16:11:47 GMT (21kb)
    [v2] Wed, 9 Nov 2016 06:58:20 GMT (21kb)

    https://arxiv.org/pdf/1611.02586v2.pdf

  • ljk December 7, 2016, 10:22

    https://arxiv.org/abs/1611.06096

    Long-Term Prospects: Mitigation of Supernova and Gamma-Ray Burst Threat to Intelligent Beings

    Milan M. Cirkovic, Branislav Vukotic

    (Submitted on 10 Oct 2016)

    We consider global catastrophic risks due to cosmic explosions (supernovae, magnetars and gamma-ray bursts) and possible mitigation strategies by humans and other hypothetical intelligent beings.

    While by their very nature these events are so huge to daunt conventional thinking on mitigation and response, we wish to argue that advanced technological civilizations would be able to develop efficient responses in the domain of astroengineering within their home planetary systems.

    In particular, we suggest that construction of shielding swarms of small objects/particles confined by electromagnetic fields could be one way of mitigating the risk of cosmic explosions and corresponding ionizing radiation surges. Such feats of astroengineering could, in principle, be detectable from afar by advanced Dysonian SETI searches.

    Comments: Accepted for publication in Acta Astronautica. 21 pages, 1 figure, 1 table

    Subjects: Popular Physics (physics.pop-ph); Space Physics (physics.space-ph)

    Cite as: arXiv:1611.06096 [physics.pop-ph]
    (or arXiv:1611.06096v1 [physics.pop-ph] for this version)

    Submission history

    From: Milan M. Cirkovic [view email]

    [v1] Mon, 10 Oct 2016 01:55:12 GMT (822kb)

    https://arxiv.org/ftp/arxiv/papers/1611/1611.06096.pdf

  • ljk December 12, 2016, 17:57

    The World According to Stanisław Lem

    By Ezra Glinter

    DECEMBER 10, 2016

    THERE’S A PARADOX at the heart of science fiction. The most basic aspiration of the genre — its very essence, really — is to transcend time and place. Not just to predict the future, but to imagine things that are totally foreign to human experience. How would an alien life form have evolved, compared with those on Earth? What will human society look like 10,000 years from now? What is artificial intelligence, anyway?

    SF tries to imagine the unimaginable, to comprehend the incomprehensible, to describe the indescribable, and to do it all in entertaining, accessible prose.

    Full article here:

    https://lareviewofbooks.org/article/world-according-stanislaw-lem/

    To quote:

    Stanisław Lem, the Polish novelist, futurologist, literary theorist, satirist, and philosophical gadfly, tried mightily to free his work from the shackles of the present. In dozens of novels, short stories, essays, metaliterary experiments, and futurological treatises, he attempted to imagine everything from a living ocean that could read human minds (Solaris) to a swarm of nonbiological mechanical insects (The Invincible) to a supercomputer many times more intelligent than its human creators (Golem XIV). In his 1964 book Summa Technologiae, Lem mocked writers whose works were merely historical fiction recast in the future — “corsairs and pirates of the thirtieth century.” It’s easy to find targets for Lem’s criticism; most SF movies are exercises in wish fulfillment, projections of a space-age Columbus in search of a final frontier. For Lem, science fiction meant thinking harder and imagining more.

    and…

    Most presciently, Lem understood that even mundane varieties of information could be disastrous in overwhelming quantities. What happens, he asked in His Master’s Voice, when “the technologies of information have led to a situation in which one can receive best the message of him who shouts the loudest, even when the most falsely?” Or, as he wrote in the same novel, “freedom of expression sometimes presents a greater threat to an idea, because forbidden thoughts may circulate in secret, but what can be done when an important fact is lost in a flood of impostors […] ?” Facebook and the deluge of fake news sites didn’t exist when Lem wrote this, but their creation wouldn’t have surprised him. The future of the United States, he wrote to Kandel, is “dark, most likely.”

  • ljk December 14, 2016, 18:04

    http://www.seti.org/seti-institute/news/take-me-your-artist

    Take Me to Your Artist

    December 12, 2016

    SETI Institute artists are being inspired by our search for alien life.

    If one thing animates scientists looking for life elsewhere in the universe, it is the power of cultural exchange—not just with alien species, but also, in more modest ways, among our own species.

    In 2010 Jill Tarter, then the director of the SETI Institute, met Charles Lindsay, a geologist turned artist, photographer, and musician who had just been awarded a Guggenheim Fellowship. She told him about the wide-ranging research happening at the institute and invited him to visit its observatory. He became “a beta test,” as he put it, for the institute’s artist-in residence program.

    Some of the products of that program are now on display at New Museum Los Gatos in California through March 2017. The exhibition, called “Making Contact,” shows what happens when contemporary artists and leading scientists exchange worldviews or, rather, universeviews.

    “There’s not an artist I’ve met who doesn’t think the idea of an artist-in-residence program at SETI Institute is just about the coolest thing they’ve ever heard,” said Lindsay, who is now director of the residency program. “The scientists to a person have loved it.”

    Read the rest at:

    http://cosmos.nautil.us/short/75/take-me-to-your-artist

  • ljk December 20, 2016, 10:13

    Review: Earth in Human Hands

    Human activity is changing the Earth, even if those changes were not the intent of that activity. Jeff Foust reviews a book by a planetary scientist and astrobiologist who examines the need to make deliberate changes to Earth to offset the damage, drawing in part upon our knowledge drawn from studies of our solar system.

    Monday, December 19, 2016

    http://www.thespacereview.com/article/3126/1

  • ljk December 20, 2016, 11:24

    Carl Sagan passed away 20 years ago today:

    https://www.rawstory.com/2016/12/carl-sagan-died-20-years-ago-today/

    Sagan talks about the Voyager Interstellar Records:

    https://www.youtube.com/watch?v=uEEb6mQtHE0

    • ljk December 20, 2016, 18:06

      Connecting with Carl Sagan at the Library of Congress

      Posted By Mark Hilverda

      2016/12/20 15:01 UTC

      Topics: history, Planetary Society People, Planetary Society, Planetary Society History

      The Library of Congress is the largest library in the world containing collections covering numerous subjects from many nations. While attending a conference near Washington, D.C., I visited the library with colleague Brandon Schoelz, Systems Administrator here at The Planetary Society. We had limited time and one reason for this particular visit: The Seth MacFarlane Collection of the Carl Sagan and Ann Druyan Archive.

      As we discovered, the archive is extensive and contains correspondence, photos, video, audio recordings, notes, manuscripts, mementos, space mission materials, and many other items collected throughout Carl Sagan’s life.

      Full article here:

      http://www.planetary.org/blogs/guest-blogs/2016/1220-connecting-with-carl-sagan.html

      To quote:

      Exploring the archive is an adventure as you never quite know what you’ll find in each folder. We started with the oversized folder containing a 1985 get-well card for Carl signed by Planetary Society staff. Featuring the Society’s early logo, it was nice to see the care staff shared for each other.

      The get-well card was relatively small, however when we opened the oversized folder we were greeted by Carl Sagan’s own copy of the Golden Record installation blueprints for the Voyager spacecraft. I did my best to quiet my exclamations of surprise, a skill in which I obtained much practice as we proceeded through our boxes from the archive.

  • Keith Henson February 12, 2017, 21:23

    Glad you mentioned KIC 8462852 (Boyajian’s Star) .

    I have thought for a considerable time about what could be called “end stage” for technophilic life. https://web.archive.org/web/20121130232045/http://hplusmagazine.com/2012/04/12/transhumanism-and-the-human-expansion-into-space-a-conflict-with-physics/

    The facts are somewhat skimpy. Looking out, we don’t see any signs of technophilic life. The choices are that we are the first or that there is a “great filter” in either our past or our future, or that life does not makes the kind of splash that can easily be seen from interstellar distances–at least so far.

    The above article makes a case for a species speeding up and not leaving their home planet because they need a heat sink.

    Boyajian’s Star, if the blinks are due to alien structures, may be an example of heat sinks on a scale similar to that of a star.

    For computation purposes, heat sinks may be more of a problem than energy.

    If there are aliens out there, it may be that the distance between the stars defeats them. That’s even more of a problem if they move into cyberspace and speed up.

    It’s very much of a mystery.

  • ljk March 13, 2017, 15:15

    What an Alien SETI Program Would Learn from Earth’s Signals

    Updated on March 04, 2017

    Tamara Wilhite

    Introduction

    We’ve been listening for alien signals for several decades, though the silence has led as many to wonder if we are listening for the right things as those wondering if there are any aliens at all. What many fail to understand is how many signals a civilization like ours produces that are lost to the background noise before anyone outside our system would hear it, much less what they might learn if they were able to pick up our signals?

    What signals would an alien civilization detect? And what could they learn about Earth from what they could receive from human transmissions?

    Full article here:

    https://hubpages.com/technology/What-an-Alien-SETI-Program-Would-Learn-from-Earths-Signals

    Geosynchronous satellites provide a wealth of information as well, to aliens who can see them. Geosynchronous satellites sit in a stationary orbit about three Earth radii out. To send signals to these satellites you need a lot of power – around half a Gigawatt to start, and more powerful signals are sent. If it is powerful enough to make it out of the atmosphere, it is powerful enough to continue traveling through space unimpeded. And these signals are multiplied by the thousands of TV stations sending their data to satellites.

    The downside to these signals is that they are only seen for about sixty seconds per 24 hour period. Someone watching Earth would see the equivalent of a very long lighthouse, silence on these frequencies followed by a daily flash. If they are at a good angle to the Earth, they’d see a rotating pattern of flashes like a disco ball, the sign someone is transmitting. It would be hard to receive much information from such flashes, such as a minute of a soccer game, but they’d be able to garner some of the same information those looking at radar frequencies would, such as how often the Earth rotates and our time to travel around the sun. They’d be able to garner some information on the size of the planet by studying satellite signal rotation time and our planet’s effects on the sun, and thus back to Kepler’s laws to get the size of the planet and our distance from the star.

  • ljk March 23, 2017, 13:09

    Scientists respond to criticisms of proposed Anthropocene

    March 23, 2017

    A team of academics led by the University of Leicester has responded to criticisms of the proposal to formalise a new geological epoch – the Anthropocene.

    Geological critics of a formalised Anthropocene have alleged that the idea did not arise from geology; that there is simply not enough physical evidence for it as strata; that it is based more on the future than on the past; that it is more a part of human history than the immensely long history of the Earth; and that it is a political statement, rather than a scientific one.

    Members of the international Anthropocene Working Group, including professors Jan Zalasiewicz, Colin Waters and Mark Williams of the University of Leicester’s Department of Geology and Dr Matt Edgeworth of the University’s School of Archaeology and Ancient History, have considered these various criticisms at length.

    In a paper published in the journal Newsletters on Stratigraphy, the 27 co-author group suggests that the Anthropocene has already seen irreversible changes to the Earth, rather than just to human societies.

    Professor Zalasiewicz explained: “As a striking and novel concept, the Anthropocene has attracted considerable support from geologists but also a range of criticism, questioning whether it should really join the Jurassic, the Pleistocene and other well-known units on the Geological Time Scale.

    “This criticism is an essential part of the testing of this concept – for the Anthropocene to be taken seriously, the science behind it must be robust and based on sound evidence.

    “Our research suggests changes to the Earth have resulted in strata that are distinctive and rich in geological detail through including such things as artificial radionuclides, plastics, fly ash, metals such as aluminium, pesticides and concrete.

    “And, while the term does reflect change of significance to human society, and may be used in social and political discussions, it is based upon an independent reality.”

    Full article here:

    https://phys.org/news/2017-03-scientists-criticisms-anthropocene.html