E.T. Won’t Be Phoning Anytime Soon

December 6th, 2011 at 11:28 am | 38 Comments |

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News that astronomers using NASA’s Kepler Space Telescope had discovered an Earth-like “Goldilocks” planet where liquid water can exist certainly deserves the attention it has received. In fact, evidence of life surviving–and even thriving–in very unlikely places on Earth tempts one to believe that, given billions of years and a decent supply of organic molecules, life (albeit simple bacterial life) will eventually develop just about anywhere liquid water exists.

All that said, even absolute evidence of bacteria or non-sentient animals on an alien world would offer plenty of grist for scientists in certain fields but little that would change the life for most people in the short term.

On the other hand, contact with an alien civilization would, obviously, have enormous impacts in every area of human endeavor ranging from science to religion. That’s why a fair number of people–some of them kooks, some of them serious scientists–have devoted time to various methods of searching for extraterrestrial intelligence.

I was, at one time, very enthusiastic about these efforts and even thought I might make it a career: I pursued a fair amount of upper-level coursework in planetary astronomy, edited a science magazine, took a first job as a science writer, and even interviewed for a job on a SETI project once. I still believe, personally, that SETI efforts are worthwhile and deserving of private support.

But, as I’ve looked at the data, I’m increasingly convinced that SETI is very unlikely to succeed in my lifetime or even my son’s.
The fundamental problem lies with the final variable of the famous “Drake Equation” that SETI researchers use to estimate the number of communicating extraterrestrial civilizations in the galaxy.

The first two parameters deal with things that observational science clearly can answer in due time: the rate of star formation in the galaxy (somewhere between 7 to 10 a year), and the percentage of stars that have planets (the latest data from Kepler indicates that it’s at least 40 percent). Next, scientists jump into slightly more speculative categories that science can still help explain: the fraction of those planets that go on to develop life and the fraction fo that life that becomes intelligent. There’s no way to answer these questions for sure but worthwhile-for-other-reasons research in our own solar system (Mars in particular) can shed light on the first variable and a better understanding of human evolution can provide some evidence on the second.

The final two variables–the percentage of those civilizations that transmit radio signals and the average life of a civilization that transmits them–seem to me beyond science’s ability to answer until we actually contact a number of other alien civilizations.

And, when one runs the equation, the final variable turns out to be the most important: even if one selects unrealistically low values for every other variable, an assumption that civilizations last billions of years would results in a galaxy teaming with intelligent life. Even if one selects high values for the other variables, on the other hand, picking a short lifespan for “transmitting civilizations” means that the universe is either devoid of intelligent life beyond Earth or that (provided that nothing can travel faster than light) any civilization we communicate with will likely be gone by the time before we receive its messages.

I’m hardly the first to notice this: Astronomer Carl Sagan devoted so much time to left-wing environmental causes in part because the Drake equation convinced him that the final variable was the one part of the equation humankind could control.

Given that humanity has been sending signals into space for nearly a century, listening for them for about 40 years, and still hasn’t found anything indicates to me that the universe isn’t teeming with intelligent life. Since everything else we know seems to suggest relatively high values for the other variables, every passing year without alien contact indicates that either intelligent life rarely develops or that civilizations which develop the ability to communicate don’t last very long.

It’s too soon to know much for certain but, despite my fondest hopes, I don’t expect to talk with E.T. anytime soon.

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38 Comments so far ↓

  • dittbub

    Perhaps humanity is the most advanced life out there. All the more reason to keep at it.

  • medinnus

    I’m more excited about Kepler 22B, a planet in the “habitable zone” that may have liquid water.

    We may or may not discover alien life – but at least we can find more planets to ruin when those idiots who deny global warming allow industry to make this planet unlivable!

    http://www.universetoday.com/91564/kepler-confirms-first-planet-in-habitable-zone-of-sun-like-star/#more-91564

  • Nanotek

    an enjoyable read

    “Since everything else we know seems to suggest relatively high values for the other variables, every passing year without alien contact indicates that either intelligent life rarely develops or that civilizations which develop the ability to communicate don’t last very long.”

    a seemingly reasonable conclusion

    that a home-grown new kind of intelligence can emerge from human technology seems more imminent, imo, than an ET contact

    http://singinst.org

    • Probabilistic

      Flat earth and epi-cyclic movement of cosmic objects too were seemingly reasonable conclusions at different points in human history. It’s just too early in the quest to tell. I’m not suggesting it should stop us from conjecturing. (Reasoned conjectures are entertaining, because they twirl around my head, tickling the insides.)

      Personally, I would be satisfied if we can show extraterrestrial evidence of self-replicating molecules that encode discrete packets of information. Can you imagine what a treasure trove it would be if we found planets with life forms at different stages of biologic evolution? A veritable extraterrestrial museum!

      The utilitarian aspects of missions like these come from solutions to difficult engineering problems, which eventually find a way to enhance our quality of life. Perhaps, we would learn something valuable about planetary climate systems, which would stop us from annihilating our own, just in time.

      • Nanotek

        “Personally, I would be satisfied if we can show extraterrestrial evidence of self-replicating molecules that encode discrete packets of information.”

        + 1

        come on Europa!

  • Bebe99

    I think continuing the search for earth-like worlds could be a gift to our descendants. At some point, long distance space travel could become a reality. It would be nice to have mapped out some interesting places to visit when that happens. Seeking out and contacting intelligent life – especially those with advanced civilizations – however would seem a huge risk to our entire species, as it is likely we’d meet aggressive, territorial creatures much like ourselves :)

    • medinnus

      *chuckles*

      So, what you saying is we need to Increase Defense Spending ™?

  • Frumplestiltskin

    Given that humanity has been sending signals into space for nearly a century, listening for them for about 40 years, and still hasn’t found anything indicates to me that the universe isn’t teaming with intelligent life.

    Epic Fail. 100 years is just our own neighborhood, and over distance a signal loses magnetic field which contains and supports information’s integrity, radio signals from a vast distance becomes background noise (provided we even know where to look at in the radio spectrum)

    Most of what we send out into space is a very weak signal as it is, 75 watts, which is sufficient for us, and we have also moved into digital and not analog signals. Who is to say some alien intelligence did not also do that early on.

    • AnBr

      The transition from analog to digital would not make that much difference. It is not like SETI is trying to reconstruct the content of an artificial signal, just its existence. The process remains the same. Where it might make a difference is that while the quality of a digital signal may hold longer, at a certain point as the signal becomes degraded, the structure falls apart where an analog signal may still exist, even if just as a ghost signal awash in the static.

      Otherwise all of your points are valid. I would also add that it does not take into account other things like directional signals like masers or in the infrared to optical frequency, lasers. Lastly, not to speculate on what it might be, but what if a technological civilization finds some other means of long distance communication other than electromagnetic radiation?

      • Cyberax

        Unfortunately, with transition to digital we’re also transitioning to spread-spectrum encodings. Which were initially designed to make radio transmissions undetectable and harder to jam.

        For example, 3G phones emit what amounts to barely detectable white noise instead of a nice modulated carrier wave.

        That’s actually an interesting hypothesis why we don’t detect other civilizations – they go ‘radio-silent’ because of greatly optimized use of radio spectrum.

  • TerryF98

    “Given that humanity has been sending signals into space for nearly a century, listening for them for about 40 years, and still hasn’t found anything indicates to me that the universe isn’t teaming with intelligent life. Since everything else we know seems to suggest relatively high values for the other variables, every passing year without alien contact indicates that either intelligent life rarely develops or that civilizations which develop the ability to communicate don’t last very long.”

    Good grief! This statement shows a stunning lack of knowledge of the distances involved, the time it takes for even light to travel those distances and the minute weakness of the sort of transmitting we have done. Epic fail.

  • ConnerMcMaub

    The fact that we aren’t inundated with aliens suggests either we are alone in the universe or faster than light travel is impossible. The latter seems far more likely from what we know.

    • Probabilistic

      Or, the universe is really, really, really, mind-boggingly vast.

      • Michigan Outsider

        These two statements (faster than light travel is not possible and that the universe is really, really, big) correlate with, rather than contradict, each other.

    • Levedi

      “absence of evidence is not evidence of absence.” We’ve only recently discovered that life can exist, even thrive, in deep sea vents. That we haven’t yet found a way to cover those vast distances or found evidence of other life doesn’t mean it can’t be done. When we’ve proven that it can’t be done and that other life doesn’t exist, then we can stop looking.

    • nhthinker

      “The fact that we aren’t inundated with aliens”

      How exactly do you know we aren’t inundated with aliens?

      Science fiction has in general done a terrible job at representing the likely technology disparity between intelligent ETs that would come or may already be here. Practical invisibility and fully stealth electronic signatures are probably less than a thousand years of technical advancement from human view of technology today. The likely encounter would be with beings that are at least a million years more technically advanced than we are. If they don’t want us to know they are monitoring us, our backward science certainly couldn’t expect to detect them.

      • Diomedes

        I was just about to say the same thing.

        If an alien species advanced enough to travel interstellar distances to reach us was actually here, my suspicion is they could easily evade any technology we have of detecting them.
        People often fail to realize just how much of a technology gap would likely exist between us and the aliens. As was aluded to, they often invoke Hollywood science fiction as a baseline. Which is a very poor example. Even 1000 years of difference between them and us would be massive on the technological scale. Imagine taking our technology back 1000 years. Bows and arrows and swords versus F-22s, missles, tanks, etc. Huge difference.

        One thing to add: another reason that aliens may not have ‘visited’ is that we are a relatively young species from the standpoint of reaching a technology level where we can make ourselves heard. Remember that it was the 1930s before we had technology capable of transmitting signals over long distances. So taking into account the long interstallar distances, if a species is, say, 100 light years away, it will still be two decades before they even know we exist. Let alone deciding to make a trek to our planet.

  • Graychin

    My comment pointing out three instances of careless word usage in this column has been deleted – and the careless word usage corrected. Coward – you could at least thank me. :D

    I renew my remark about the swipe from this English-challenged author against the esteemed Carl Sagan and his “left-wing environmental causes.” It’s just the obligatory swipe against something (anything) left leaning in every Frum Forum piece.

  • ratgov

    There actually is a flaw in the drake equation. It isn’t the amount of time that a civilization exist, it’s the amount of time that it sends and receive radio (there is another drake equation for each kind of message transmission “window”). I would not be surprised at all if we discover a superior method of communication in the next 100 years and than our planet will most likely go radio silent. Did our civilization last for 200 years? of course not.

  • Primrose

    The problem with statements of probability is that we forget that when a coin is tossed it doesn’t know the odds. Yes, it usually flips this way but it could flip that because it isn’t fulfilling a rule.

    So it may seem unlikely we will hear from anytime soon, that will be exactly true up until the very moment it all completely changes. That could be tomorrow. We don’t even have the experience to predict accurately as we do the coin.

    If Columbus had been coming from Asia not Europe and veered into the wrong section of the Pacific, he might assume there was no land and turn around. We just don’t know where it is crowded and where it isn’t and we are hardly covering the entire sky. We simply don’t know enough to make any predictions.

    • anniemargret

      ….and arrogance precedes ignorance. I’m going to go there.

      UFO.

      The mainstream science community has been virtually silent on this subject. And yet….they long for more information that has been basically denied to them, given the embargo in peer reviewed journals that prevent scientists from writing intelligently about them.

      The notion that astronomers have the last word on this subject is false. Scratch your average astronomer and you will find a person that knows nothing about the subject. This global phenomenon has been ongoing and resilient to prosaic interpretations.

      In 2005, I conducted a survey (unpublished) of astronomers on the subject of UFOs. Contrary to what most people expect to hear, there was a sizeable percentage of the respondents to learn more about the subject but felt a prejudice in the science community against learning more. There was, and sadly still is, a ‘giggle factor’ in relation to this phenomenon.

      It is patently possible, even probable, that UFOs represent another intelligence, non-human, non terrestrial, or terrestrial but not ‘ours.’

      How many people on this forum have taken the time and energy to actually read the data and information that researchers have collected over the decades? And no, I’m not talking about the ad nauseum conversation about Roswell. Dr Allen Hynek, the Northwestern scientist hired by the government to dispense the notion that UFOs represented anything inter-planetary started out an arch-skeptic, and by his death, remained fervent that the UFO data and information was an ‘embarrassment of riches’ waiting for more research and interpretation.

      This is an area that is ripe for a group of scientists to give it the seriousness its due, because there is a large majority of people the world over who already have. That includes military and airline pilots, military officials, and government officials who have already spoken out. It includes the thousands of individuals from all walks of life who have given testimony and the physical traces and radar reports that support their reports.

      That in the year 2011 we dismiss this phenomenon as unworthy of attention while scientists ignore its reality, and while they speculate on the vastness of space and the viability that sentient life has sprung elsewhere is a testament to our arrogance. Or perhaps it’s simply so unbelievable that we turn away?

      I don’t know. But I have read enough on the subject to convince me that we are still ignoring something within our midst that may have an impact on our society and the world’s is not only stupid, and that it may have dangerous implications as well.

      • Demosthenes

        http://www.cracked.com/article_18690_5-ufo-sightings-that-even-non-crazy-people-find-creepy.html

        Worth reading in its entirety, but here are some excerpts from what the editors call the ‘creepiest’ UFO sighting. (The article has a link to the transcript of the entire radio dialogue with Melbourne ATC).

        “In his final words with Melbourne Air Traffic Control, … Valentich described being followed by a UFO:

        Valentich: Melbourne, this is Delta Sierra Juliet. Is there any known traffic below five thousand?

        Melbourne: No known traffic.

        Valentich: I am… seems to be a large aircraft below five thousand.

        Melbourne: What type of aircraft is it?

        Valentich: I cannot affirm. It is four bright… it seems to me like landing lights.

        Like Gorman, Valentich claimed the aircraft was intentionally buzzing him, zipping past, getting too close and going incredibly fast. At one point Valentich said the aircraft stopped in mid-air, and he orbited around it to get a good look:

        Valentich: It’s got a green light and sort of metallic like… it’s all shiny on the outside… … it just vanished…

        Later:

        Valentich: Ah… Melbourne that strange aircraft is hovering on top of me again… (two seconds open microphone)… it is hovering and it’s not an aircraft

        Those were Valentich’s last words to Air Traffic Control, and maybe his last words to anyone. What followed were 17 seconds of a metallic scraping sound. Neither Valentich nor his plane were ever seen again. The investigation has been one, long, frustrating dead end.”

  • Demosthenes

    The other thing to consider is that our universe with its particular laws of physics &c. is just a tiny drop in an unfathomably vast ocean of multiverses. Extraterrestrial beings inhabiting our same physical universe, composed of the same kind of matter that we are composed of, are theoretically possible, but are also among the least interesting and exotic kinds of beings. If you take any religious worldview half-seriously, especially the views of Native American or South and Central Asian religions, it’s not in any way a question of “will we find other beings out there?”, because we already have, and we have been communicating with them for thousands of years.

    Of course atheists and atomists will claim that e.g. shamanic ritual practices are all man-made, that shamans and other ritual priests never actually contact extraterrestrial beings, and that any religion or folk-religion claiming extraterrestrial origins or contact with extraterrestrial beings is only fabricated by people for the sake of controlling other people. From my perspective, the funniest thing about this claim is that shamans have been dealing with extraterrestrial beings since before recorded history; realist atomism (in the modern sense) is barely two hundred years old. We’ll see which perspective survives for another 10,000+ years.

    • anniemargret

      Whatever we ‘know’ about the universe in the year 2011 is probably infinitesimally smaller than what is actually real. With each passing month, year, scientists discover new marvels that they may have theorized about, or are shocked about. Even Einstein’s laws of relativity are now being called into question. Only a decade ago, that wouldn’t have been considered possible.

      I find that people that ridicule the idea of UFOs=another intelligence are lacking in scope. Any scientist that tells us that it is not ‘possible’ using 21st century physics is being deliberately non-aware, or has been so ingrained with scientific dogma about what’s true or not true, should be cautious in their assessments.

      I personally have always thought that what we know and understand about reality on this planet is probably wrong…and perhaps so wrong that it would blow our minds to know otherwise. But like children who need to grow up, we have to at least give these things some credence, pursue research, and keep an open mind.

      (And no, not enough open mind for the brains to fall out, but not buttoned up tight either!)

      • nhthinker

        The giggle factor of ETs is all based on the hubris of humans.
        Many scientists would rather the universe be random than to seriously consider if ETs that are at least a million years more technically advanced than modern humans darting around our galaxy under our noses.

        Giggling allows them the illusion of being absolutely assured that there is no greater intellect nor more advanced society other than themselves. Hubris can be very self-satisfying.

  • John Frodo

    Life on another planet would mean the book of Genesis was nothing but a fairy tale, then maybe we could all just move on into adulthood.

  • Carney

    One relatively easy way to begin answering this question is to seek life or its fossil remains on Mars. While it is dry and cold now, Mars had warm wet conditions for five times the length of time it took for life to emerge on Earth after such conditions began here. Fossil remains could well remain, and perhaps life itself might cling on within rocks (as some lichens do here), or in underground water. If even primitive life exists on Mars, within two planets in the same solar system, then it’s reasonable to suppose that life is common in the galaxy, and that advanced and even intelligent life can also exist.

    • Diomedes

      And Europa and Titan as well.

      Europa is a giant ball of water. Albeit covered by ice. Nonetheless, water has been the most common medium from which life has arisen and could arise elsewhere.

      Titan is another interesting candidate. Although it doesn’t have liquid water, it has lakes of liquid ethane and methane. We currently don’t have any evidence that life could arise in a liquid medium other than water. So a discovery on Titan would have profound implications of how we view worlds with the ‘potential’ for life.

  • Oldskool

    The question of life out there has become passe compared to the questions being asked in quantum physics, imo. If life is basically a byproduct of chemistry it’s safe to assume it’s all over the universe, in one form or another.

  • Flugendorf

    I went looking for an estimate of what we would be likely to detect. For what it’s worth, SETI has some information about the distance at which Earth’s transmissions would presently be detectable, here:

    http://setifaq.org/faq.html#1.2.3

    The upshot: if the receiving dish were the size of Arecibo, 305 meters across, then even the best-case transmission, UHF TV carrier waves, could be detected at a maximum distance of 0.3 of a light year from Earth. (That doesn’t include detecting TV pictures, which could only be detected in the inner solar system.) The nearest star is a little over 4 light years away.

    For this reason, SETI is looking for other kinds of transmissions – narrowband transmissions, where all the transmitter’s power is put into a very narrow range of frequencies. However, the reason anyone would be doing that at very high power would be likely to be in order to specifically and deliberately try to communicate at interstellar distances – at great expense in effort, energy, initial construction, etc. It’s hard to estimate how likely anyone out there is to go to this much trouble to try to be heard by unknown aliens. (We’re not doing it.) But anyone who is not doing it is almost certainly not going to be found by accident, and definitely not through their transmissions, because their transmissions will be undetectable.

    One reason to try to communicate across interstellar distances is to communicate, not with unknown aliens out of unspecified motivations, but with one’s own interstellar colonists or interstellar probes. However, this supposes that they have managed to cross the nearby interstellar gulfs at all, something vastly more difficult and conjectural than making a transmission. Notwithstanding that, if they did have colonists or probes out there to talk to, the best way in which to get the most distance out of transmission power is to make a directional transmission. Any such transmissions have a fantastically reduced chance of being detected by us, because the chance of those transmissions being accidentally pointed straight toward us is so low.

    Mr. Lehrer wrote, “Given that humanity has been sending signals into space for nearly a century, listening for them for about 40 years, and still hasn’t found anything indicates to me that the universe isn’t teeming with intelligent life.” Based on this picture, I’d say neither Mr. Lehrer nor I nor anyone else can make any inferences at all about the rate of incidence of intelligent life or elsewhere in the universe based on not having heard anything. (Cheers reruns could have been airing in every third star system, all precisely at the time in the past that would match with light from their stars reaching Earth now, and we wouldn’t know anything.) We wouldn’t have the data Mr. Lehrer thinks we’ve detected the absence of.

  • Flugendorf

    Sorry, double-posted by accident/confusion. :o )

  • FormerConservative

    “…any civilization we communicate with will likely be gone by the time before we receive its messages.”
    In fact, we are the civilization that will probably be gone before hearing a response back… The proof that our civilization is unlikely to last very long is quite simple: “The name Newt Gingrich is frequently used in the same sentence as the words: “potential Republican Party nominee.”

    Q.E.D.