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Searching for Extraterrestrial Life and Intelligence: Knowable and Unknowable

We recently looked at the $100 million infusion into the SETI effort by Yuri Milner, with backing by major figures in the field. When I’m considering SETI developments, I always look to Michael Michaud, whose judicious perspective in his book Contact with Alien Civilizations (Copernicus, 2007) remains a touchstone. He served in senior international science and technology positions with the U.S. State Department and two American embassies and acted as chairman of working groups at the International Academy of Astronautics that discuss SETI issues, in addition to publishing numerous articles and papers on the implications of contact.

Michaud recently addressed the Astrobiology Science Conference 2015 (AbSciCon2015) in Chicago in mid-June, more than a month before the Breakthrough Initiatives announcement, and touched on many of the relevant themes. What follows is an essay drawn from that talk but expanded with new material and references. What if a very advanced technology is indistinguishable not from magic but from nature? Read on for Michaud’s perspective on our thus far unsuccessful search for other civilizations, what it implies about our methods and ourselves, and where we go from here.

by Michael A.G. Michaud



For centuries, many humans have believed that life and intelligence arise on other worlds. We have repeatedly anticipated their discovery, hoping to find them on the Moon, on the other planets of our solar system, and now on planets orbiting other stars.

More than a century ago, a few astronomers observing Mars at the limits of their instruments perceived lines on the Martian surface. Some came to an erroneous conclusion that they were channels or canals constructed by intelligent beings. (1) A newer technology, robotic spacecraft, revealed in the 1960s that the canals did not exist outside the observers’ imaginations. Some things are not only unknown; they may be unknowable with the scientific means available to us at the time.

That has led some very intelligent people to conclude that such things can never be known. French philosopher Auguste Comte declared in 1842 that, although we may learn the forms, distances, sizes and motions of stars, we can never know their chemical composition. (2) Yet Fraunhofer already had discovered dark lines in the Sun’s spectrum by an early form of the spectroscopy that later revealed the chemistry of astronomical objects. What seems unknowable now may become knowable later.


Before 1959, most astronomers would have said that detecting signals from technological civilizations at interstellar distances was impossible. Cocconi and Morrison pointed out that the means had come into our hands in the form of radio astronomy. (3) What had been unknowable became knowable through scientific and technological advance.

That inspired a Search for Extraterrestrial Intelligence that seeks evidence of extraterrestrial technology in the form of radio signals. What may be the least likely from of alien biology – a transmitting intelligence –seemed the easiest to detect with the means we had at that time.

After 55 years of intermittent searches, or about two human generations, we now have the perspective to treat SETI as an historical phenomenon. There have been well over one hundred search programs. Searches have been broadened beyond radio signals to visible regions of the spectrum and to the infrared, notably to seek emissions from Dyson spheres.

This effort has constrained some dimensions of search strategy, such as the probability of beacons. Yet there has been no confirmed detection.

There are many potential explanations for SETI’s lack of success. Here I will mention only one, voiced by SETI pioneer Frank Drake: Radio and visual spectrum transmissions may be temporary artifacts of technological intelligence. There might be only a narrow window of time in the development of technological civilizations when noisy electromagnetic signals are generated in large amounts. (4)

Those scientists who have dedicated much of their careers to SETI deserve respect for maintaining scientific standards as they sought to achieve a very difficult goal. Yet, after half a century, it is easy to become discouraged about SETI. We can hope that new observing capabilities like the Square Kilometer Array will make some form of detection more likely, but there is no guarantee of success.

The lack of a confirmed finding could lead to a false negative, reflecting the limitations of our technologies, our search strategies, and our assumptions.
Civilizations more technologically advanced than ours might be invisible to our present means of searching. Compressed digital data may be indistinguishable from random noise.

Arthur Clarke famously said that any sufficiently advanced technology would be indistinguishable from magic. (5) What if a very advanced technology is indistinguishable from nature?

SETI Institute astronomer Seth Shostak was quoted as saying in 2011 that “If this experiment has merit, it’s going to succeed within two or three decades. If it doesn’t, then there’s something fundamentally wrong with our assumptions.” (6)

Shostak also has written that our own developmental trajectory suggests that, shortly after inventing technology capable of interstellar communication, a society also develops artificial intelligence. If so, AI may constitute the majority of the sentience in the cosmos. Consequently, looking for signals from habitable planets could be the wrong approach for SETI. (7)

Eventual success still may be possible, though it might require a broader strategy and technical means not yet available to us. The existence of alien civilizations can not be disproved.


Why do we seek distant intelligence, even in the face of repeated failure? Is SETI just an extension of normal science? I suggested in 1993 that we search for communicating civilizations in the hope that contact with intelligent others will introduce new and hopefully positive factors into human affairs. (8) The discovery of extraterrestrial intelligence would involve much more than science, raising important philosophical and societal questions.

Even without a discovery, the search has inspired creative thought. As the SETI literature has grown and diversified, we have seen many proposed scenarios of discovery, and many different predictions of what contact might bring. What was once an exotic, small-scale scientific enterprise has led to a vast, multidisciplinary thought experiment about the nature and behavior of intelligence, both on and beyond the Earth.

The prospect of interacting with an alien intelligence has stimulated both hopes and fears; predictions of the consequences have ranged from utopian to apocalyptic. Some authors have imagined extraterrestrials as noble, altruistic philosopher-kings who will help us to solve our problems. Others have imagined ruthless alien invaders who will enslave or destroy us.

These are exaggerations of our own behaviors, at our best and at our worst. It is time to escape Hollywood, particularly the tiresome invasion scenario.

Astronomers Ivan Almar and Jill Tarter proposed a scale to categorize the impact of contact. (9) Shostak gave us hypothetical examples based on that scale, ranging from benign to disastrous. He later published a fictional story which ended with the Earth’s atmosphere bursting into flame. (10)


That brings me to the debate about Active SETI, also known as Messaging to Extraterrestrial Intelligence. METI advocates wish to send unusually powerful targeted signals to alert other technological civilizations to our existence in the hope of stimulating a response.

It is easy to understand the frustration of those who have devoted their working lives to discovering signals generated by alien beings. But METI is not physical or biological science. It is an attempt to provoke a reaction from a technological civilization whose capabilities and intentions are not known to us.

That reminds us that a factor is missing from the Drake Equation, a factor almost impossible to quantify: alien motivations. Intelligent beings can make choices and take actions. We cannot assume that their actions will be ones that we prefer. Our assumptions about alien behavior have not passed the empirical test.

METI advocates assume there could not be any negative consequences from contact, for two reasons. First, more technologically advanced extraterrestrials are benign, an unproven assumption. Chinese science fiction writer Cixin Liu put it this way:

On Earth, humankind can step onto another continent and, without a thought, destroy the kindred civilizations found there through warfare and disease. But when they gaze up at the stars, they turn sentimental and believe that if extraterrestrial intelligences exist, they must be civilizations bound by universal, noble, moral sentiments, as if cherishing and loving different forms of life are parts of a self-evident universal code of conduct. (11)

Second, METI advocates assume that interstellar flight by robotic spacecraft is impossible. We humans already have reached all the planetary bodies in our own solar system through such spacecraft, a feat that many considered impossible as late as the 1950s. Some of our machines have left our solar system. There already exists an extensive scientific and engineering literature on interstellar probes, frequently reported on the Centauri Dreams blog. Before dismissing interstellar flight by machines on the basis of its cost to us, we should try to estimate its feasibility for a civilization much more technologically advanced than our own.

Consider an example from our own history. Humans began populating the Americas about 17,000 years ago. (12) For thousands of years, after the land bridge closed, oceans insulated newly indigenous Americans from the peoples of other continents. Technological advance, in the form of reliable ocean-going ships and gunpowder weapons, made them vulnerable. The growing credibility of direct contact by uninhabited machines requires us to widen the range of possible consequences.

Whatever the consequences of calling attention to ourselves might be, our descendants will not be able to opt out of them. Prudence suggests that we should conduct a global conversation on this issue before we embark on a sustained program of broadcasting our presence with more powerful transmissions.

Almar proposed what he called the San Marino scale, intended to quantify the potential hazard of transmissions. The main factors are the signal strength in relation to Earth’s natural background radiation, and characteristics of the transmission such as direction and duration. (13)

One approach would be to set quantitative thresholds for the proposed signals, such as the normal power, duration, and directionality of pulses from military and planetary radars. Above that level, transmissions would require approval from the organizations that fund, control, or regulate the largest radars and transmitting radio telescopes. Radio telescopes capable of transmitting powerful signals to distant stars have been funded by taxpayers, making their use a legitimate subject for governmental policy decisions.

A discussion, perhaps within the United Nations, could lead to an agreed statement of international policy on such transmissions. We already have seen successful examples of this procedure in space debris and in planetary defense against asteroid impacts.

We could shift the debate to a more positive agenda. Expanding SETI beyond the microwave window could be more productive than sending our own signals.

An editorial in Nature in 2009 put it this way: “Will we want to beam messages to those other Earths? That question is not resolved. But we should at least listen. Humankind may decide that it does not want to open its mouth, but it would be foolish to cover its ears.” (14)


The discovery of planets in orbit around other stars is changing the game. We should recall that some astronomers had been skeptical, even dismissive, of the idea that such planets existed. (15)

Finding many extrasolar planets—including some that may be near analogs of the Earth—enables us to begin filling in the suitable planet factor in the Drake Equation. On this point, the SETI optimists were largely right.

Thanks to technological advance and clever people, we soon may be able to search for what is likely to be far more widespread than transmitting civilizations: evidence of biology. What once was considered unknowable again is becoming knowable.

Searching for evidence of life with powerful new observing technologies coming on line in the next decade may have a higher probability of success than searching for signals from ETI. Finding a form of biology on one of those planets would give us a second data point for the life factor in the Drake equation, a second L.

Some believe that discovering alien life just a matter of time, effort, and improving technology. NASA’s Chief Scientist was quoted as saying that we’re going to have strong indications of life beyond Earth within a decade, and definitive evidence within 20 to 30 years. (16)

That optimism is admirable. Yet the nagging voice of history suggests caution.
We might recall older mistakes, such as interpreting the periodic darkening of the Martian surface as evidence of the seasonal spread of plant life.

At the same time, we should beware of false negatives due to the limitations of our equipment and our search strategies. Once again, we are observing at the limits of our technologies. A false negative might reflect our assumptions about extrasolar biology, which may be very different from the biology we know on Earth.

There also could be false positives, or evidence that is inconclusive or disputed. The Mars Rock controversy of 1996 may be a preview of what will happen. We are on the fringes of knowability, the time when observations are most likely to lead to ambiguous results.

Before astronomers began finding planets around other stars, our model of planetary systems was based on the one example we knew—our own solar system.
Now we know that our case is not typical. (17) Is that also true of biology, intelligence, and behavior? Our models of extrasolar life and intelligence, usually inspired by Earthly examples, may prove to be exceptions to galactic general rules.

We may be underestimating how alien the products of utterly different evolutions could be. No one anticipated the strange creatures that scientists first found around Pacific sea floor vents in 1977. The search for extrasolar life will spark new thought experiments about the nature of very different evolutions.

Those who seek life on distant planets may be wise to remember the SETI experience. Like the search for signals, the search for extrasolar life may be more difficult than its most optimistic supporters/advocates foresee. (18) Our expectations may exceed the grasp of science as we know it today. Yet a failure to detect such life would not prove the absence of life elsewhere.

While discovering simpler forms of life would be fascinating for scientists, non-intelligent life will inspire less public interest than alien intelligence. Such life can not grant us wisdom, nor can it threaten us. Emotional debates about the possible consequences of contact—our hopes and our fears– may fade.

The SETI experience tells us that there is no guarantee of success. Yet the search is likely to continue, in one form or another.


Detecting a habitable world, or extraterrestrial life, could inspire greater optimism about finding ETI by making the existence of alien intelligence seem more probable. Could studies of extrasolar planets reveal evidence of a technological civilization?
Some suggest that evidence of certain chemicals in exoplanet atmospheres may imply energy consumption or waste products of industry. (19) But fuel burning and waste-generating industry may be temporary phenomena in a planet’s history.
Observations might miss non-technological intelligence, or intelligence that employs technologies that we cannot detect or that are unknown to us.

The discovery of an alien civilization may not mean communication with it; there could be contact without communication. What we are looking for is not a dialogue of centuries, but an existence proof.

A failure to find evidence of intelligence could discourage those who hope for inspiration or assistance from outside. We may never receive guidance from distant stars, leaving us responsible for our own fate. That could help revive the anthropocentrism that SETI has challenged for half a century.

Even if sapient aliens exist elsewhere in the galaxy, our inability to find them with existing technologies could leave us effectively alone. The scientific paradigm of Earth’s uniqueness as the abode of life and intelligence has not yet been broken.

Finding ETI may be a multi-generational task. Discovery may require rigorous and repetitive searching and data analysis that last beyond individual human lifetimes. It may require a broader strategy, and a willingness to look in new places. It may require technical means not yet available to us.


We are in a transitional period. While both SETI and the search for life on extrasolar planets will go on, we are seeing an implicit shift of emphasis from seeking deliberate signals of technological intelligence to searching for evidence of life, which may be much more common.

A major factor in this shift is the vast disproportion in resources. The science of planet-hunting is funded much more generously than the science of seeking signals from other technological civilizations. SETI scientists can only dream of a taxpayer-funded capability equivalent to the Kepler telescope.

Planet hunters hope to make use of several powerful new instruments (James Webb Space Telescope, Thirty Meter Telescope, Giant Magellan Telescope, European Very Large Telescope, Transiting Exoplanet Survey Satellite). But detecting Earth’s twin may have to wait a decade or two. (20)

Ultimately, we may need interstellar probes for closer observation of potential life-bearing planets. Except for our Moon, all of our explorations in our solar system have been conducted by machines, not by inhabited spacecraft. That is even more likely at the interstellar scale.

In the long run, our own interstellar probes could lead to a role reversal. If they are detected by intelligent aliens, the impact of contact might flow from us to them.


There is another idea implicit in finding and characterizing distant worlds: some might be seen as future homes for our descendants. The theme of human expansion, so prominent in spaceflight literature, may be revived. As Paul Gilster put it, finding a habitable world within twenty light years, coupled with a failure of SETI, would be a powerful boost in building an interstellar consensus. (21) The ambition to travel to those distant worlds, and to convert them to human use, could generate a paradigm that we might call anthropocentrism with a goal.

Statistically, the nearest non-transiting habitable zone Earth-size planet may be within 23 light years.(22) One can envision a hundred year robotic mission to the star hosting such a planet; one human generation might start the project knowing that future generations would finish it.

Encouraging early work on interstellar probes is a small but necessary contribution. I hope that the new Nexus for Exoplanet System Science will reach out to those doing serious scientific and engineering work on interstellar flight by machines.

We may never find alien intelligences out there, but someday we may find extraterrestrial intelligences descended from us. What seems impossible now may become possible later.

Yet there is nothing inevitable about interstellar exploration. It has to be chosen as a course of action, and funded. We cannot foresee all the threats or opportunities that could motivate such ventures, nor can we be sure that those motivations will be enough to make starflight a necessary task for near future human generations.

If interstellar flight is possible, why don’t we see them? Even if technological civilizations have the scientific and technological knowledge to launch interstellar probes, they may not do so. Expansion could fail if technological societies are unable to agree on a course of action. They may suffer failures of perception, failures of imagination, failures of nerve, or failures of politics.


What nation, or which people, will lead this effort? In the near term, the United States will remain the biggest player in space, with the world’s largest and most diverse programs. But American elites lack consensus about where to go, or when.
They are turning away from shared visionary goals that would require us to amass public resources for long-term, large scale non-commercial projects like interstellar exploration or eventual human expansion.

In 1989, as the Cold War was ending, Francis Fukuyama wrote that the worldwide ideological struggle that brought forth daring, courage, imagination, and idealism will be replaced by economic calculation, the endless solving of technical problems, environmental concerns, and the satisfaction of sophisticated consumer demands. (23)

A society whose elites are preoccupied with immediate gratification will not support the vision of human expansion. Some pessimists have suggested that the age of manned spaceflight may be coming to a close. (24) Others express nostalgia for an age of exploration that ended with the mission to Pluto. (25)

Analysts predict that China will become the world’s largest economy less than fifteen years from now. (26) China’s space program is newer and smaller than its American counterpart, but it is growing. China is on the rise, with a determination to succeed in great societal endeavors and an authoritarian political system which makes that possible.

History is not about immutable fate. It is about the choices that humans make.(27)

I end with a quotation from another non-scientist, William Shakespeare:

There is a tide in the affairs of men
Which, taken at the flood, leads on to fortune…
On such a full sea are we now afloat:
And we must take the current when it serves,
Or lose our ventures.


(1) The history is described in Michael J. Crowe, The Extraterrestrial Life Debate, 1750-1900, Cambridge University Press, 1986, 480-540. Republished by Dover in 1999.

(2) Auguste Comte, The Positive Philosophy, Book II, Chapter 1 (1842).

(3) Giuseppe Cocconi and Philip Morrison, “Searching for Interstellar Communications,” Nature 184 (1959), 844-846.

(4) See Michael A.G. Michaud, Contact with Alien Civilizations, Copernicus (Springer), 264, and “Signs of Life,” The Economist, February 27, 2010, 87.

(5) Arthur C. Clarke, “Aspects of Science Fiction,” in Greetings, Carbon-Based Bipeds! Collected Essays, 1934-1998, St. Martin’s Press, 1999, 399.

(6) Quoted in Tim Folger, “Contact: The Day After, Scientific American, January 2011, 41-45.

(7) Shostak, Seth, “Searching for Non-Biological Extraterrestrial Intelligence,” paper presented at the Astrobiology Science Conference, Chicago, June 2015.

(8) Michaud, Michael A.G., “SETI and Diplomacy,” in G. Seth Shostak, editor, Progress in the Search for Extraterrestrial Life, Astronomical Society of the Pacific Conference Series, Volume 74, 1995, 551-554.

(9) Almar, Ivan and Jill Tarter, “The Discovery of ETI as a High Consequence, Low-Probability Event,” Acta Astronautica, 68 (2011), 358-361.

(10) Shostak, Seth, “The Rio Scale Applied to Fictional SETI Detections,” paper presented at the International Astronautical Congress in 2002, and “The Second Signal,” Communications of the Association for Computing Machinery 57 (January 2014), 128-129.

(11) Cixin Liu, The Three Body Problem, Doherty (Tor), 2014, 395. Published in China in 2006. Translated by Ken Liu.

(12) Ewen Callaway, “South America settled in one go,” Nature 520 (30 April 2015), 598-599.

(13) Hecht, Jeff and Paul Schuch, “The San Marino Scale: A New Analytical Tool for Assessing Transmission Risk,” Acta Astronautica 60 (2007), 57-59.

(14) “SETI at 50,” Nature 461 (17 September 2009), 316.

(15) Sage, Leslie. “Introduction to special section on exoplanets,” Nature 513 (2014), 327.

(16) Wall, Mike, Space.com. “Top NASA Scientist: We’ll Find Signs of Alien Life within a Decade,” nbcnews.com, accessed April 18, 2015.

(17) Sage, op.cit.

(18) LePage, Andrew, Astrobiology: A Cautionary Tale. Posted on Centauri-dreams.org February 27, 2015.

(19) “Signs of Life,” The Economist, April 17, 2010, 89-90.

(20) Anglada, Guillem, Doppler Worlds and M-Dwarf Planets, posted on Centauri-Dreams.org May 15, 2015.

(21) Gilster, Paul. Spaceflight and Legends, posted on Centauri Dreams December 16, 2011.

(22) Sara Seager, “Exoplanets Everywhere,” Sky and Telescope, August 2013, 18-26.

(23) “Nietzsche is not dead,” The Economist, October 15, 1994, 113.

(24) “The End of the Space Age,” The Economist, July 2, 2011, 7.

(25) Dennis Overbye, “A Great Ride While it Lasted,” The New York Times, July 7, 2015.

(26) Shanker, Thom. “Study Predicts Future for U.S. as No. 2 Economy.” The New York Times, December 11, 2012.

(27) Paine, S.C.M. The Wars for Asia, 1911-1949, Cambridge University Press, 2012, 7.


Comments on this entry are closed.

  • John July 24, 2015, 12:54

    I found this interesting, thoughtful, and aa compelling read. I don’t entirely agree with the characterisation of the risks associated with METI: The question, to my mind, is not whether we can count on any hypothetical contactees as being benign – we certainly should not. It is whether the potential benefits of interacting with an ET intelligence outweigh the risks. Perhaps METI is an idea that should wait for a time when we a re a multiplanets species, and therefore less vulnerable?

    On the idea of ET intelligence using technolgy that is unknown to us, my feeling is that we should take that idea further: Are missing something fundamental? about the form ETI could take? It is worth pointing out that we have co-existed with creatures of considerable intelligence, even primitive tool using intelligence, on Earth for most of humankinds existence (dolphins, great apes, chimpanzees, corvids, to name but a few). But for most of recorded history we have not seen them as such, instead looking to the sky for evidence of gods and the depths for evidence of demons. Just maybe we need to change our own perception of what form ET life and ETI might take before we can search with real hope of success. Perhaps we should simply explore, and keep an open mind…?

  • Harold Daughety July 24, 2015, 12:58

    RE: “That reminds us that a factor is missing from the Drake Equation, a factor almost impossible to quantify: alien motivations. Intelligent beings can make choices and take actions. We cannot assume that their actions will be ones that we prefer. Our assumptions about alien behavior have not passed the empirical test. ”

    As I see it, this is the most serious flaw in our search for ETI. We are looking for ourselves. We are scientifically curious: an advanced civilization would be scientific and thus curious. We would consume all available energy, so we look for Dyson spheres. We use long wavelength AM radio, so . . . and on and on.

    It may be that immature intelligences pass a critical point in maturation, that they either destroy themselves or progress to the final state. We cannot even guess what that civilization would be, but it seems reasonable that they would neither call us nor answer the phone. Why bother? we are neither asset nor threat.

  • Wojciech J July 24, 2015, 14:28

    Interesting article, a couple of points:
    SETI has its very limited assumptions, and I personally don’t believe they are right about them.A civilization wanting to contact us would do so already, due to time difference and much more advanced technology.
    It is worth remembering that SETI research for those deeply interested are not conclusive. There were unexplained signals and detections, including ambigous results regarding Dyson Spheres.
    METI itself is harmless, anyone studying astronomy knows our biosphere and civilization is broadcasting signals that visible to others(night lights, composition of atmosphere).
    Alien planets are a must for study through interstellar expeditions, but the very ability to travel between stars makes the need for colonization dissappear.
    Finally we should remeber time and scale.SETI on cosmic scale operated under nanosecond, and observed a very tiny portion of space.
    As I wrote before, I don’t count on getting any message from other civilizations, but we might get a glimpse of their shadows.

  • ljk July 24, 2015, 14:47

    If you want to know why mainstream SETI has been rather limited for so long (aside from the cultural blinders and ridicule and overall lack of funding and resources), read this online book about the history of the field that goes into details one seldom finds elsewhere on the subject:


  • Alex Tolley July 24, 2015, 15:56

    I think the search for life, rather than intelligence makes a lot more sense. I am not convinced that not sentient life will be a bit of a turnoff for the public. A planet of “dinosaurs” would likely be captivating if we were able to make nature documentaries of it. By the nth planet of similar exotic life, it might get boring for the public. There may be sentient creatures that are pre-technological, or even technological but do not wish to make themselves known. These scenarios invite sending interstellar probes. There may even be probes in our solar system if we look hard enough, a sign that intelligence is/was out there.

    If the universe does [unexpectedly] turn out to be lifeless, that would allow us to go forth and colonize with a clear conscience and a possible mandate to green the universe.

  • Larry Kennedy July 24, 2015, 16:21

    @ Harold Daughety
    ” it seems reasonable that they would neither call us nor answer the phone. Why bother? we are neither asset nor threat.”

    I absolutely agree with the sentiment. I’m certainly not against SETI, on the contrary, but I do have very low expectations.

  • James Stilwell July 24, 2015, 16:34

    When the poles and Greenland ice melt to soil and Florida is under a hundred feet of water, the frantic search will be on for Earth 2…The Artilects will be of great assistance traveling through the cosmic rays to map the best way to Earth 2…On the other hand, the end of our interglacial period is near, give or take a thousand years…Either way, the test of human prowess is about to begin…

  • Mike Fidler July 24, 2015, 16:40

    There is one problem the Drake Equation has not addressed. How rare total solar eclipses could be on other exoplanets. We live in a unique time when our moon is 400 times closer to the earth then the sun and the sun is 400 time larger then our moon, giving us a TOTAL solar eclipse that happens nowhere else in the solar system. In human belief we can look at it in three general ways, the religious view, god created it that way, the conservative view, well maybe someone was here before and created it that way, and the Scientific concept that this is just a coincidence. If it is just a coincidence, then that must be billions of intelligent species in our galaxy.

  • Astronist July 24, 2015, 18:04

    “They [Americans] are turning away from shared visionary goals that would require us to amass public resources for long-term, large scale non-commercial projects like interstellar exploration or eventual human expansion.” — Not relevant at this stage. Interstellar exploration and colonisation is not a job for America, or even for Earth, but for a well-developed Solar System. What matters right now is putting passenger access to space onto a commercial footing, and here the USA is streets ahead of China.

  • Andrew Palfreyman July 24, 2015, 18:08

    I hope part of that $100M will go towards a robust compute infrastructure capable of implementing KLT detection, as described by Claudio Maccone. As an engineer I have to mention that a lead candidate for the most cost-effective way to do that is a GPU array – the same hardware that is optimal for Deep Learning artificial intelligence. Perhaps someone closer to the purse strings is reading this blog and can comment.

  • Astronist July 24, 2015, 18:10

    Two points which I believe you do not take sufficient account of in this essay.

    Firstly, SETI is not a well-designed experiment, as it depends upon a positive result (an alien signal). If there is no signal, or an enigmatic non-repeated signal only heard once (the “Wow!” signal), then it has made no progress towards answering the question it started with.

    Secondly, given the feasibility of interstellar travel, the scenario in which humanity is the first intelligence to arise in the Galaxy is perfectly plausible.

  • DCM July 24, 2015, 18:45

    “James Stilwell July 24, 2015 at 16:34”

    No, there’s enough land for life to continue. Such has happened when human type creatures existed and the present ongoing interglacial when humans exist. people migrate and come up with new technologies. Don’t get worked up over politically motivated pseudoscience or interpretations.

    But we do need to go elsewhere to insure really long term survival.

    I haven’t always been for continuing SETI now that decades have yielded nothing identifiable but we do need to monitor the cosmos for signals because we don’t know what might be out there.

  • Kamal Ali July 24, 2015, 19:51

    “Yet, after half a century, it is easy to become discouraged about SETI. ”
    “If this experiment has merit, it’s going to succeed within two or three decades. If it doesn’t, then there’s something fundamentally wrong with our assumptions.”

    We need to find a better way of measuring progress. All these references to ‘amount of trying time’ are anchored to human life span. What would we make of a comment made by an extraterrestrial who had much shorter lifetimes than us who would say “I’ve tried for 30minutes and still haven’t found anything”. Given the amount of the parameter space in terms of “where-to-look-magnitude x years x frequencies x modalities x …”: we’ve covered a very small amount of that space. (By modality I mean electromagnetic versus probes versus quantum-entanglement versus god knows what…). What we can probably say with this negative result over 50 years is that the galaxy is not dense in number of civilizations transmitting omnidirectional signals with strength much greater than Arecibo. By dense i mean in terms of time,frequency and energy. They may be out there transmitting unidirectionally, or for short times or with lower energies : all that has not been ruled out.

  • Harold Daughety July 24, 2015, 23:03

    If FTL interstellar travel were possible, maybe finding planets to colonize would be a worthy venture. I see no reason to believe that FTL space ships are possible. It makes for good heroic fiction and gives ancient stories a new life in exotic new settings . Humanity cannot move en masse to a new home , and human presence in local space will be limited to the few pioneering groups and their descendants, maybe supplemented with frozen embryos to maintain genetic diversity. ET’s are likewise constrained to their local space and to millennia-long voyages.
    However, in my opinion, SETI is worthwhile if for no other reason that to show that humanity is not the pinnacle achievement of a divine creation.

  • Laura July 25, 2015, 3:04

    Although I’ve long followed SETI efforts, I’ve also long had low expectations, for many of the reasons discussed in this excellent article. I fear that we’re like a more primitive human civilization, that wondering whether there are intelligent beings on the moon, attempt to communicate with them by means of drums, horns, or smoke signals. We use the technology that we have. We could be living in a universe abuzz with communication, but be no more aware of it than an isolated tribe with no contact with the larger world would be aware of the storm of electromagnetic communication that covers the planet.

    Another major concern has been the fact that compared to the age of the Milky Way, and the age of our planet, and the time that life has existed here, and the time that human life has existed – the one hundred years or so that we’ve had electromagnetic communication is infinitesimally small, a mere instant in the great scheme of things. The chance that there would be another intelligent life form at the same technology level, at the same moment on the cosmic time scale, is extremely small.

    If there’s intelligent life out there that has persisted for millions of years or longer, its nature may well be unimaginable to us. For all we know, they may be everywhere, but in a form undetectable to us. They may even have moved away.

    But one thing I’m pretty sure of. Whether we’re alone or not, the possibilities boggle the mind.

  • J. Jason Wentworth July 25, 2015, 4:15

    While I don’t lose any sleep over this, Mr. Michaud’s assertion that the “tired invasion scenario” should be abandoned seems naive to me. While many would say, “Aliens have no reason to covet our Earth, because they could just build O’Neill-type space colonies in their own star systems if their home planets became hard or impossible to inhabit anymore,” we don’t know–and won’t, until/unless it’s tried–if such colonies are feasible to build, or if they are enduring. (Other reasons for invasions might also be in play–Carl Sagan wrote that interstellar religious evangelism can’t be ruled out.) Also:

    The exoplanets discovered thus far suggest that very close Earth analogs–where we and other terrestrial creatures could live happily without artificial supports (barring insurmountable problems from local alien microbes, of course)–are very rare. If our world was becoming uninhabitable and if space colonies aren’t a practical alternative, we would–in desperation–seek out another, suitable extrasolar planet to live on (and woe to any indigenous intelligent inhabitants, especially if they were below our technological level!). Alien races who faced the same problem would also seek out exoplanets that they could inhabit without external aids. In addition:

    I am rather surprised that while he mentioned interstellar probes, in his discussion of METI he didn’t consider messenger probes (Bracewell probes), which would facilitate METI contacts over much shorter (interplanetary rather than interstellar) distances. But in fairness, even finding and contacting such a probe, if one exists here in our solar system, could potentially have negative consequences for us. As friendly as it might appear to be, its purpose might be to ascertain our level of technological development so that its makers could formulate their plans against us accordingly. As well (and more cheerfully):

    While it is often said that more advanced races would have no interest in us, that notion doesn’t ring true to me. Technological prowess isn’t the only “figure of merit” of a civilization. The Romans were the undisputed masters of the known world, yet their philosophy, mathematics, science, and religion were greatly influenced by (and in many cases, provided by) Greece, whose engineering, economic, and military achievements were greatly overshadowed by those of Rome. Even the primitive Australian Aborigines, as the Australian anthropologist A.P. Elkin wrote, knew things about psychology that western intellectuals had only recently discovered. In his book “The Galactic Club,” Ronald Bracewell likewise speculated that even a superior technological civilization might be interested in our philosophical ideas, simply because they would be different and might address things the aliens hadn’t thought of.

  • Antonio July 25, 2015, 4:27

    Regarding METI, I still don’t understand why these people discourage it. Either METI is dangerous or it’s not. Its danger or lack of it is objective, not subjective. So, we have two possibilities:

    – METI is dangerous. Thus, SETI is searching for Extraterrestrial Idiots, that either don’t know or disregard the danger. Or worse, it’s searching for dangerous extraterrestrials that transmit benign-looking messages in order to obtain a reply from fools like us and thus find us and kill us.

    – METI is not dangerous. In this case, we are the idiots that don’t transmit and loss the opportunity to obtain a reply from the civilizations that are waiting a message in order to know that we want to communicate. Also, even if we receive a message from some civilization, if we follow the arguments of antiMETI proponents, we will never reply, since “we don’t know ETI motivations”.

    I don’t see any logical consistency in the antiMETI movement. It’s like a phallacy from ignorance: we don’t know anything and we will never know, so do nothing (or useless activities like SETI to which you will not reply) for all eternity.

  • Adam July 25, 2015, 4:43

    John Barnes’s cautionary tale “Enrico Fermi & the Dead Cat” reminds us that even listening is risky. But what is life without taking risks?

  • Wojciech J July 25, 2015, 5:16

    Since it would make much more sense for a civilization to assemble an expedition and explore a detectable biosphere than beam for tens of millions of years messages into space in vain hope somebody will receive them(and it would be much more energy and resource consuming too), we can assume that a deliberate contact was never pursued. Otherwise we would already be contacted.
    Hence in my view it is much more useful to try to detect non-direct communication in the galaxy and signs of mega-engineering works and structures.
    I wouldn’t discounted of course possibilities of extra-galactic transmissions, but such things probably wouldn’t last long.

    ” haven’t always been for continuing SETI now that decades have yielded nothing ”
    As I mentioned before SETI hasn’t been either negative or positive. You can find detections of detections of anomalous signals in its findings or potential Dyson Spheres but these remain unverifiable. Of course it is not as much as positive outcome, but technically it wasn’t negative either.

    Btw, China is finishing construction of a new radio telescope that it will be larger than the one at Arecibo

  • Al Jackson July 25, 2015, 5:47

    “Arthur Clarke famously said that any sufficiently advanced technology would be indistinguishable from magic. What if a very advanced technology is indistinguishable from nature?”

    What if a sufficiently advanced technological civilization is not just indistinguishable from magic or nature, but just indistinguishable?

  • Larry Kennedy July 25, 2015, 10:14

    I think you’re right on about the time problem. As large as the signal/reception problems are, I agree the time problem is greater.

  • Larry Kennedy July 25, 2015, 10:22

    I knew the dreaded jungle was going to come up. Many things discussed on these pages have very little real evidence in either direction. The idea the galaxy is a jungle is not one of these. We have one huge piece of evidence. They are not here.
    As frequently pointed out the “Fermi paradox” has many plausible answers. If you believe in the galactic jungle you wipe out virtually all of them in one stroke.
    If a predatory species were roaming the galaxy, they would be here.

  • DCM July 25, 2015, 13:15

    “Harold Daughety July 24, 2015 at 23:03
    ….SETI is worthwhile if for no other reason that to show that humanity is not the pinnacle achievement of a divine creation.”

    Please. It’s time to dispense with the last century’s cultivated self-hatred. And a species has no “ego”, while we’re at it. Churchmen in the 1600s were sometimes upset by new astronomy because it upset the theory they’d operated on since Classical times, not because “mankind’s ego” was “shaken”. Same for Darwinism…it threatened a long established theory that many vested interests held.
    Last century saw deliberate negativity directed at ourselves because of the two world wars and because it serves to discourage and beat down people in preparation for the totalitarian state all leftists crave. It’s another outdated idea that must yield to reality.
    Catch up with the times.

  • J. Jason Wentworth July 25, 2015, 16:54

    Antonio wrote (in part): “Regarding METI, I still don’t understand why these people discourage it. Either METI is dangerous or it’s not. Its danger or lack of it is objective, not subjective.”

    I agree, but the potential danger in it need not keep us from trying it. Personally, I support METI, while admitting that it could possibly lead to very unpleasant consequences for humanity. Like all contacts between one people and another, engaging in METI is a calculated risk; it could lead to great trade in knowledge and ideas, or it could invite destruction. I think (and many others no doubt agree, while still others do not) that METI is worth the risk. Also:

    Adam, I’m not familiar with the story “Enrico Fermi & the Dead Cat,” but I agree that even listening (and receiving a message) could have negative disruptive consequences, although not for all of humanity. The 1950s science fiction movie “Red Planet Mars” explored this, where radio signals from a (non-hostile, for a change!) Martian civilization conveyed concepts that caused societal disintegration on Earth. While such a thing could possibly result from either SETI or METI, I think humanity, in the aggregate, could handle paradigm-changing knowledge (although the adjustment period, for some people, would be uncomfortable). In addition:

    I agree with Harold Daughety that “SETI is worthwhile if for no other reason that to show that humanity is not the pinnacle achievement of a divine creation.” We may find that the pinnacle of Divine creation is indeed elsewhere; C.S. Lewis, in his philosophical writings as well as his science fiction novels (his essay in Arthur C. Clarke’s book “The Coming of the Space Age” expresses his thoughts on the matter) speculated that this could be the case.

  • I Brouwer July 25, 2015, 18:15

    In the vain of the remark that technology might be indistinguishable from magic/nature, i would think that even if intelligence started out comparable to ours it`s needs would evolve like technology would. At some point physical labour and transport would largely become obsolete, intelligence digitalised and only information would move.

    At that point, a civilisation could become largely invisible to us, no more emissions, infrastructure and light pollution. The state our civilisation is in might be a short lived one also until we become invisible to the outside ourselves. This `information-state` might also explain an absence of dyson-sphere`s: a mature civilisation might not need that much resources/energy.

    The amount of energy our civilisation needs now could be just a result of our hungry biology, losing our biology might be the key to our prolonged existence, it could also make the need to explore and colonise obsolete and capitalism and individualism a thing of the past.
    (hope this makes sense, i`m not much of a scientist)

  • LocalFluff July 25, 2015, 19:32

    My suggestion for a message to send:
    “-Cut the crap! Just tell us what the meaning is with all this stuff.”
    (A thousand years later the answer arrives)
    “-We haven’t got a clue, and we’ve been working hard on it during millions of years. We’ve even forgotten when or where we started. We were actually hoping that you maybe had figured out something about it. Please keep us on your email list just in case.”

  • ljk July 25, 2015, 19:38

    Seems we have yet another “first contact” issue between two disparate societies right here on this planet:


    How do we protect this so-called “primitive” tribe? Especially since they are the ones making contact with neighboring villages and have even attacked and killed several people? It is a bit too late for the Prime Directive, I am afraid. And do we isolate them like animals in a national park? Do we deny them modern medicine and other amenities at the very least?

    I know one thing, this won’t end like in Avatar.

  • LocalFluff July 25, 2015, 19:57

    DNA/protein based life must be out there. It consists of the simplest molecules of the most common elements. There might be other bases for life, but we can certainly not be the only instance of the DNA/protein logic.

    The molecular combinatorics of DNA/protein is uncountable. But the types of functions it accomplishes are maybe limited. Things like cell division and eyesight. There are flat five edged proteins, and flat six edged proteins. Together they build soccer ball like containers which are used by virus and to house controlled protein folding. They can be constructed in uncountably many different ways, and there are many different versions, but they still fill the same function.

    So it seems sane to assume that biology has created similar functions out there, as it has done here. Even if it is chemically unrelated and apart. But all life on Earth is one and the same, so it is not really a statistically useful sample. 99.5% of human DNA is around in other species, we are them are us. Otherworldly DNA/protein lifeforms might have a completely different set of higher functions than what our evolution has discovered. But it is pretty hard to imagine that they don’t have some kind of five and six edged flat proteins that can stick together to form a soccer ball. I bet they are pretty much like us after all. With their own version of fantasies about how weird we must be after billions of years of evolution.

  • LocalFluff July 25, 2015, 20:11

    One thing we know about the aliens is that they are diverse. Light travel time forbids coordination in historical time scales between colonies. There cannot be one civilization on many stars, they must become different with time. So there are all kinds out there (if any). Including the most dangerous ones imaginable…

  • Larry Kennedy July 25, 2015, 22:41

    @ LocalFluff
    RE ” Including the most dangerous ones imaginable”
    It seems to me they would have a problem. If they sent out a colony of the most dangerous it would probably be closer to them than anyone else for thousands of years. As pointed out by many before, they would have no way to maintain control.

  • J. Jason Wentworth July 26, 2015, 5:04

    I Brouwer and LocalFluff brought up points that, at humanity’s current state of knowledge/ignorance, can only be addressed properly in SETI and/or METI (so as to not miss possible contacts via making the wrong assumptions) by assuming that “both sides” are correct.

    Artificial intelligence (artilect) extraterrestrial civilizations are popular and interesting to think about these days. But as John MacVey pointed out in his book “Space Weapons, Space War,” we cannot assume that every technological device or process that we can conceive of will be possible, no matter how much time and effort is put into developing it; the laws of physics may make some things forever impossible for us. Until/unless true AI is developed, artilect beings and civilizations are pure speculation. At the same time, however (as MacVey also pointed out, in his book “Interstellar Travel: Past, Present, and Future”), it is equally unwise to assume that just because something appears impossible now (faster-than-light travel, or *effectively* FTL hyper-dimensional travel, as he discussed in that book), it will always remain so. This creates an extra burden on SETI and METI work in our time (although that burden should decrease as we learn more). It is this:

    Until we know that certain things (artilects, FTL travel, O’Neill-type space colonies that aliens might move to [or build in] other star systems lacking planets in their habitable zones, Dyson spheres, etc.) are or are not possible (or feasible), we risk missing contacts by assuming that they do–or do not–exist. At the present time, the only way to avoid this is to follow the Gray Path of searching for all of these things, and allocating time, equipment, resources, and personnel accordingly, based on “best guess” probabilities (which will change as we learn more). It’s a more difficult course of action, to be sure (if we knew enough to eliminate some of these factors, it would definitely make the search easier), but our current ignorance leaves us little alternative. However:

    This need not make such an all-inclusive search a discouraging, Sisyphean task–undoubtedly many serendipitous discoveries in astronomy and even astrophysics would result from it. It might even be possible to “piggyback” some of these search efforts onto non-SETI astronomical observations (radio, optical, gravity wave [if/when that becomes available]), so that there would be less competition for observing time with observatories and astronomical satellites.

  • Jer July 26, 2015, 12:34

    I believe that we should pursue METI. It should be pursued soon and without significant consensus. Also, METI will fail in its strict sense of positively receiving response to a directed message and that’s okay.

    Pursuit: Technological development, funding and scholarly attraction of same, leading to further breakthroughs and side projects – at least as important as any CERN-type atom-smashing project. (risk): Negligible. An alien society or any of its members having reached a technological level of being able to recognize and contact us has necessarily reached a sociological and psychological stage that complexity destruction (our society) is just as abhorrent and nonsensical as industrialized cannibalism is to us. To try to find precedent is history is irrational because there is no analog between two intellectual species of such different technological levels who can still communicate in a society-scale way. I believe there is necessarily a causative link (as can be suggested in psychology) between ubiquitous technological level (with its well-planned ways and likely post-scarcity values) -and-conquestorial (or even competitive) tendencies (severely inversely proportional). This leaves us with quantifying risk. I point many toward’s Pascal’s Wager – a legendary metric for determining whether we should choose to believe in god. The gist is that we should because the risks are so significant. The fallacy with this is in its utter lack of data, its dependence on our own level of poor risk adversity, and the prevailing pressures of current norms and mores. To use this type of risk assessment (which seems to go on in the heads of many who lean towards an endless thoughtfulness and patience) is to lead society into a profound intellectual and technological stagnation. Life is very valuable and society similarly, but NOT that valuable.

    Without significant consensus: There has never, ever, in the history of society, been a large technological (or even economical) undertaking that had overwhelming support (> 50%) from each group within a combination of a democratically-elected governments, their unoppressed populations, and a representative group of experts for all aspects of payment, design, and construction. Not Ever. Not the Intl Space Station. Not any CERN project. Not ITER. Resisting clear and imminent threats have been the only situations that had overwhelming support from all these groups. That being said, any billionaire, research university, etc., should proceed with all speed to undertake this.

    Failure: I believe that the vast, vast, overwhelming (love that word) of Kardashev 1+ society populations are not located on a planet or even around a star, but are part of a mass diaspora of self-contained ships with ideal environments and heavily independent systems with very little interaction with large (and necessarily erratic and requiring so much environmental modification) interstellar bodies -and- very little interest in contacting planet-locked civilizations. So, we’re left with an endless mist of self-contained populations utterly unpredictable in path, destination, and intentions (but all non-conquering). My 2 cents.

  • Alex Tolley July 26, 2015, 16:47

    I believe that the vast, vast, overwhelming (love that word) of Kardashev 1+ society populations are not located on a planet or even around a star, but are part of a mass diaspora of self-contained ships with ideal environments and heavily independent systems with very little interaction with large (and necessarily erratic and requiring so much environmental modification) interstellar bodies -and- very little interest in contacting planet-locked civilizations. So, we’re left with an endless mist of self-contained populations utterly unpredictable in path, destination, and intentions (but all non-conquering).

    Might there be some in our solar system?

  • Brian July 26, 2015, 17:11

    No we can’t know the intentions of an alien race, we really can’t know anything until we contact them. However I don’t feel the case Hostility is very good, whats the motivation? Even if they did happen to be religious extremists thats always been something to rally around rather than a cause for conflict. Space is big and the earth doesn’t really have anything you can’t get on an uninhabited rock closer to home nor does the Earth pose a security risk to anyone, even if it did what do we have to fight over? We shouldn’t base our policies on what we can’t know or what we imagine could go wrong, that would put us in an impossible situation.

  • Eric July 26, 2015, 21:07

    Is the Breakthrough Listen project about to waste all its time and money by not using a stop and stare strategy to detect Benford beacons? Seriously, why don’t they just complete the Allen Array and stare at the the galactic center for ten years?

  • LocalFluff July 27, 2015, 3:24

    Thankfully physics is “easy”! We can imagine that we one day will understand all physics. But we know that we can never figure out biology. Maybe there’s a super combination of proteins that do marvels (such as cause consciousness? and what other phenomena “like that” are possible?), but we will never figure it out. It is unknowable in principle, combinatorically. Not even quantum computers may hack it, because biological processes might use quantum computing themselves! As suggested by the discipline “quantum biology”. An intro: https://www.youtube.com/watch?v=bLeEsYDlXJk

  • LocalFluff July 27, 2015, 3:43

    Speculating about the origin of civilization, I like this beautiful theory: Birds learned humans to sing and from that we developed language. And since music is mathematical, we got mathematical thinking at the same time.

  • Antonio July 27, 2015, 6:41


    Yeah, it’s like the people that said that the LHC would create a black hole and destroy the Earth, so we should not switch it on. But, by the same “logic”, we should not use any particle accelerator either. Indeed, we should not do any science whatsoever. Yeah, let’s stagnate and finally return to the caves!

    The reality is that to know about something, we need to make experiments and take risks. And most of the time these risks are very very small, and the risk of ignorance is completely ignored by these people.

  • Harold Daughety July 27, 2015, 6:56

    @LocalFluff RE: proteins and such: Carbon/hydrogen/oxygen/nitrogen (CHON) based life is probable because of a number of factors. First, the prime raw materials are metal cyanides and water. Second, the reactions involved are low energy. Third, the system carries within itself the fundamental patterns based on covalent bond geometries. And, as you pointed out, amino acids build into more complex structures constrained by the fundamental geometry. So CHON life on earth probably had numerous starts on earth rather than a singular event, and it is foolish to believe it did not have similar starts elsewhere in the galaxy.

  • Larry Kennedy July 27, 2015, 8:20

    @Harold Daughety
    If the life is easy people are right you would indeed expect more than one start on Earth. It seems to me one powerful argument against this could be chirality.
    I could believe that plenty of microscopic life with opposite chirality could exist but I would expect strong evidence would show up in organic accumulations.

  • ljk July 27, 2015, 9:22

    Antonio said on July 27, 2015 at 6:41:

    “Yeah, it’s like the people that said that the LHC would create a black hole and destroy the Earth, so we should not switch it on. But, by the same “logic”, we should not use any particle accelerator either. Indeed, we should not do any science whatsoever. Yeah, let’s stagnate and finally return to the caves!”

    There were concerns that detonating the first atomic bomb would literally set Earth’s atmosphere ablaze:


  • G. Cecil July 27, 2015, 15:24

    As usual, all I read here relates to broadcasting/detecting EM radiation. Given that this radn couples efficiently to only 4% of the mass density of matter, the rest ostensibly ‘dark’, why assume that communication is occurring in what may well be a minor and quaint side band? Are we just drunks looking under the streetlamp for our keys?

  • LocalFluff July 27, 2015, 20:03

    @Harold Daughety
    HONC is as simple as 1234, their number of valence electrons. It’s Lego blocks. Geometry. It is beyond my pay grade, but I think that also on a deeper level of quantum mechanics, it’s all about geometry too. Interfering “waves” of probability of location. Physics is the science of where things are and how they turn. Is there maybe some more interesting question to be asked?

    I was always taught that chemistry is only about molecules sharing electrons. And I did do a semester of (non-organic) chemistry at a university. Only now when I’m actually interested and have the fantastic internet at my fingertips and eyeballs, I learn that all that messy silly legacy nomenclature about “acidity” is actually about molecules sharing single protons too. Poor hydrogens having been robbed off of their last electron by some greedy oxygen, wanders off in dissatisfaction to some greener grass on another side. Well, my understanding might not be completely realistic, but however could it be? I mean, can’t someone please just tell me what all this stuff is? Yes I’ve heard about the inventory list of Lego blocks and the map of where they are. But I get the feeling that we’re missing something obvious.

  • LocalFluff July 27, 2015, 20:31

    @G. Cecil
    But “we” are going beyond EM now. A chunk of the Antarctica has been turned into a neutrino telescope, and they catch about one a week. They could name them individually. But it is taking off. Then there are gravity wave telescope attempts. Astronomy is going beyond light, and it happens in our days.

  • Jer July 27, 2015, 21:50

    In response: Alex Tolley July 26, 2015 at 16:47

    “… So, we’re left with an endless mist of self-contained populations utterly unpredictable in path, destination, and intentions (but all non-conquering).

    Might there be some in our solar system?

    I fear that such a civilization type (as a vast majority) would be one eager for its constituents to disperse widely but not with such an increasing acceleration that would send it into other civilizations or their ‘mists’. Type of a cloud that stays loosely associated (finding a minimum equilibrium density) but enjoys its own individual groupings and their idealized environments (necessarily and intensely introspective – an inevitable intelligent species’ mindset?))(similar to the kids of today – so networked, so comfortable in their immediate surroundings, yet so alone)

  • G. Cecil July 27, 2015, 22:21

    @localFluff, exactly! although neutrinos will remain a low-bit-rate channel. But next generation astrophysics will be employing gravitational waves, which couple just as well to DM. Indeed, this is just scratching the surface, we have no idea what dark energy is and how it might be controlled and modulated. My point is: don’t assume that we can eavesdrop on conversations between advanced beings by using EM. FTL chats would by definition be undetectable and, because there is nothing to exclude them and there are overwhelming advantages, we could assume that they are ongoing.

    I expect that we’ll find high confidence evidence of microbial life within the next couple of decades, but nothing more. Look at Earth’s history, 80% was exactly that and a few more unfortunate events would have made the rest just as dull (other than to microbiologists).

  • Alex Tolley July 27, 2015, 22:52

    @G. Cecil – even assuming we knew what dark matter is, are you suggesting that they may have different mechanism to carry electromagnetic force than photons? In that same vein, what about dark energy?

  • J. Jason Wentworth July 28, 2015, 2:51

    LocalFluff wrote:

    “@G. Cecil
    But “we” are going beyond EM now. A chunk of the Antarctica has been turned into a neutrino telescope, and they catch about one a week. They could name them individually. But it is taking off. Then there are gravity wave telescope attempts. Astronomy is going beyond light, and it happens in our days.”

    Ah–you’ve just inspired a possible way that we might create directional neutrino signals (which wouldn’t be blocked or interfered with by anything to speak of, even over thousands or perhaps millions of light years). If a fusion reaction of the type we can create (D–D, D–He3, etc.) occurred while the constituents were moving rapidly in one direction–say, in a long linear accelerator, or maybe a “stellerator” magnetic confinement device (the reaction need not be self-sustaining for this application)–any neutrinos produced by the reaction might be “beamed” (or as close to this as electrically-neutral particles can be) in a preferred direction. If the reaction was modulated, it might be possible to send dots and dashes or prime number pictographs via neutrinos.

  • ljk July 28, 2015, 8:41

    So are talking about hooking up a particle accelerator to a controlled fusion reactor to send neutrino messages into space? Piece o’ cake.

    Humans did send a neutrino message on a small scale in 2012:


    So as we pro-ETI folks like to say, if we can do it, jut imagine what a more advanced society might achieve.

    Anyone have connections with anyone at any neutrino observatories about looking into monitoring for artificial messages? Tell them it is the 21st Century if they are hesitant or negative in response.