Searching for Technosignatures. Evidence of Intelligent Alien Civilizations


Are we alone in the Universe? It’s one of the most difficult and important
questions that humanity can ask. As Arthur C. Clarke noted, it’s equally
terrifying whether the answer is yes or no. So if you’re going to find evidence of extraterrestrial
civilizations, you want to be absolutely certain about your evidence. You want to find “technosignatures”, unmistakable
proof that aliens are out there. In September 2018, NASA hosted the Technosignatures
Workshop at the Lunar and Planetary Institute in Houston Texas. This was a meeting of 50 astronomers and space
scientists with an expertise in technosignatures. And the attendees were a who’s who in the
field, like Jill Tarter, David Kipping, Adam Frank, David Grinspoon and Jason Wright. Over the course of three days, the participants
gave dozens of presentations with titles like “Megastructures in waste heat and transit”,
or “Technosignatures in atmospheres/planetary evolution”. Fortunately all of their presentations are
fully available online, and I plan to mine these for future episodes. I’ll put a link into the shownotes so you
can watch them too. The outcome of this meeting was put into a
document called “NASA and the Search for Technosignatures”, and released to the public
on November 28, 2018. It’s only 65 pages and pretty easy to read
through, so I highly recommend you check it out. Again, I’ll link it up below. So what does the report say? How can we find those alien civilizations? Researchers in the field generally cite SETI
researcher Jill Tarter as the person who coined the term “technosignatures”. She defined this as any evidence that technology
has been used to modify its environment. Walk around Earth and you’ll see buildings,
roads and machines which are evidence of our technology. Sample the soil, atmosphere and oceans and
you’ll see the evidence of our pollution. See the Earth at night and the cities glow
with illumination, and the whole planet blazes in the radio spectrum from our communications
system. Technosignatures could include similar structures
and pollution on other worlds, but also the kinds of technologies that we don’t have
yet. Powerful lasers communicating between star
systems or as a propulsion system, the waste heat generated by megastructures like Dyson
Spheres, or even more exotic technologies that we don’t understand yet. Let’s look at some specific kinds of technosignatures: The gold standard has always been radio technosignatures,
messages transmitted by aliens in the radio portion of the electromagnetic spectrum. These are ideal because an extremely narrowband
radio signal can only come from an artificial source. The Sun is emitting photons across the radio
spectrum, but if you saw a signal that was in a very specific frequency, it would immediately
tell you that an intelligent civilization was emitting it. Furthermore, once you’ve scanned all the
stars at a given frequency, you can rule that frequency out and move onto the next one. The problem with radio emissions, however,
is that humans generate enormous amounts of radio transmissions. You might be using a radio transmission to
watch this video right now. So there are a tremendous amount of false
signals and noise to comb through. The famous WOW signal, for example, was seen
only a single time and never again, and could have been a radio signal bouncing off a piece
of space junk. The search space for radio transmissions is
enormous, which you consider the different power of transmitters aliens could be using,
the frequencies, how much information they’re sending, in which directions, and if that
data is polarized or modulated. In fact, researchers estimated that SETI has
scanned about a million trillionths of the places they could look. Of course, as Jill Tarter says, “you don’t
need to search all the world’s oceans to find a fish” Sensitive wide-field, broadband surveys like
the Allen Array are already operational, and future surveys should speed up the process. Instead of looking for radio emissions, we
could also be looking for optical and near-infrared lasers. We could be seeing their attempted communications
or use of lasers for interplanetary and interstellar spacecraft. According to Andrew Howard, one of the participants
at the workshop, if alien civilizations were sending out repeating short laser pulses,
it would be obviously from an intelligent source. In fact, several surveys have performed comprehensive
searches of the sky, looking for these quickly pulsing lasers, searching tens of thousands
of stars without seeing any signals. Of course, with hundreds of billions of stars
in the Milky Way, we’re still just scratching the surface. Instead of searching for aliens trying to
communicate with us, we could see evidence of aliens just going about with their lives. Every time you use energy, and certain amount
of released as heat. More advanced civilizations will be using
more energy and thus generating more heat. Imagine a Dyson Sphere megastructure, where
an advanced civilization is using all the energy from its star. This would generate an enormous amount of
waste heat that would create a very unusual infrared signature in the sky. The Technosignatures report suggests searching
the sky for objects blazing in the infrared in a temperature range of 100 – 300 Kelvin. You could see individual Dyson spheres here
in the galaxy, or entire galaxies which have been harnessed by an advanced civilization
– this is known as a Type III civilization in the Kardashev scale. But even a megastructure that only partly
obscures its star would give off a clear signal. When the megastructure passes in front of
its star – or transits – the drop in light could be detectable. In fact, NASA’s Kepler Space Telescope was
the perfect megastructure finding mission, in addition to its actual job of finding planets
through their transits. However, over the course of 200,000 stars
that Kepler observed, it didn’t see any evidence of artificial transits. Instead of searching the galaxy for evidence
of aliens, we might want to scan our own Solar System instead. The discovery of the interstellar asteroid
Oumuamua demonstrated that rocks can make the journey from star to star, so it’s not
impossible for an alien civilization to send their probes to other stars like our Sun. The surfaces of most worlds in the Solar System
have been scanned down to the kilometer resolution or so, and nothing has been found, but smaller
objects could be there on the surface of Europa, or Titan, or Mercury. And interplanetary space itself is enormous,
there are almost limitless places in the Solar System where a probe could be hiding. This is the state of the search for technosignatures
today. But the technology is increasing at a rapid
rate, with new observatories and techniques coming online. What future ways could we search for evidence
of aliens out there? I’ll get to that in a second, but first
I’d like to thank: John Edward Hunnell
John Head Sebas1509
John Ellis Douglas Jeffrey Marraccini
Andrej Holubek Daniel Deprima
Cyril Perlitschke And the rest of our 794 patrons for their
generous support. If you love what we’re doing and want to
get in on the action, head over to patreon.com/universetoday. Our tools for examining the Universe are getting
so much better. New missions, new telescopes and powerful
computers to help crunch all the data. What new ideas are there to search technosignatures? Instead of searching for a beamed transmission
intended for us, could we detect the leaked information from a civilization? Their version of radio and television transmissions. Could we detect alien sitcoms? The most powerful radio telescopes on Earth
couldn’t detect anything for more than a couple of light-years away, but the Square
Kilometer Array could do the trick. This is an enormous radio telescope under
development in Australia and South Africa. Once complete in 2030, the full array will
be capable of detecting radio leakage from a civilization like Earth at interstellar
distances. Another method of detecting aliens could come
from their impact on the atmosphere of their planet. Measure the Earth’s atmosphere and you’d
find the industrial pollutants like the ozone layer-damaging chlorofluorocarbons. When the James Webb Space Telescope comes
online, I think in the year 3000, it will be sensitive enough to spot several pollutants
in the atmospheres of exoplanets with just 2 days of observations. James Webb is going to be busy, but I’m
sure astronomers will be directing it at all the Earth-sized worlds turned up by TESS and
other exoplanet surveys. Might as well check. Here on Earth our populations are clustered
up into cities, which give off a large amount of infrared radiation. These are known as “heat islands”, and
a sensitive enough infrared telescope could detect these heat spots on other planets. Although there are natural sources of heat,
like from forest fires and volcanoes, waste energy gives off a very specific wavelength
of infrared radiation. The technosignatures workshop also proposed
that light pollution could be detectable, because it would be directed in the opposite
direction of the star. In other words, they turn on their lights
at night. It might even be possible to see worlds undergoing
some kind of climate crisis, nuclear apocalypse or in the midst of a massive geoengineering
project to remake their planet by searching for signs that the planet is out of balance. In order to search for these technosignatures,
the attendees recommended that scientists undertake new surveys with the best ground
and space-based telescopes on hand, pushing these instruments to their limits. Groundbreaking new instruments like the 39-meter
Extremely Large Telescope, James Webb and the Square Kilometer Array will push our capabilities
even further. They suggested new instruments be developed
capable of directly imagine Earth-sized planets around sunlike stars, as well as more sensitive
infrared capabilities. Highly sensitive photometry will help see
transiting megastructures at greater distances, and infrared photometry will give us the ability
to detect climate changes. One proposed telescope called the Exo-Life
Finder, would consist of 9-25 huge telescopes arranged in a ring. It would be sensitive enough to see continents
and oceans on an Earth-sized world light-years away. Our ability to detect alien civilizations
is getting better and better every day. Whether they intend to communicate with us,
or we just detect them through their impact on their local environment, the hunt is on. Some day I hope we’ll get an answer to that
big question, are we alone in the Universe? What do you think? Let me know your thoughts in the comments. Once a week I gather up all my space news
into a single email newsletter and send it out. It’s got pictures, brief highlights about
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to get the one you want. And I’ll put the links in the shownotes. And finally, here’s a playlist




Comments
  1. How would they differentiate between artificial and natural transits when all they see is the dip in light?
    There could be civilisations that are technically advanced but it can't be detected.In the instance of light pollution there could be a reason thet they don't do anything but sleep after sunset and so don't need artificial lighting.
    I suppose that really we just don't know what we are looking for but hope that they are similar to us enough to detect.

  2. Why not prioritize the radio bands that allow for the most data transfer?? Sane could apply to lasers I guess? I heard Robert Zubrin bring this up in a speech.

  3. I curious, if you know a mathematician and astrophysicist can he or she figure out the odds of zoo hypothesis happening right now? universe about 14 billions yrs that's no end in sight. seem to me like some kind of beings are already here, probably watching us like some sort of entertainment but I just want to know what he or she figured it to be?
    ok, and take this in consideration too, if they were in just the right environment . they can quickly evolve into a technical civilization in the very early universe that's remotely possible. thinks

  4. What do you think about the repeating radio signals we just picked up? What do you think it is? Was it an ancient alien civilisation from 1.5 billion years ago trying to communicate like we are now?

  5. This is the ultimate question for the human species. It is nice to see that FINALLY, government agencies are taking this seriously. IMO, I think that the diversity of any potential intelligent alien world will certainly surprise us, if we are smart enough to detect it at all, and we may not be looking for the correct way of finding intelligence. We know so little. We have only recently realized the vastness of the universe, so we have so little experience at this. Isaac Arthur explores this topic in great detail. It could be that using radio waves to communicate is a VERY primitive form of communication, that is very short-lived for emerging intelligent beings. Their signals may be so advance, that we may not be capable of detecting them. BUT! We have to try.

    We are fledglings. We have only just left our planet and begun to explore our own backyard, the solar system. I love the idea of looking in the infrared spectrum. The laws of thermodynamics can not be broken, as far as we know. A step in the right direction. My prediction is that any signal we detect, may be 'dumbed down' for us to find. I think that looking for Dyson spheres and other things is VERY short sighted. This is a concept that we think is inevitable, but that assumes that other intelligent beings face the same problems, or would logically arrive at the same conclusion, that we earthlings do. IMO, in a mere 200 years, we may look at Dyson Spheres as a laughable idea, as we discover better concepts, that we can't yet comprehend. It seems that many of the logical conclusions we make, are what OUR species may do in the future, but I think it is almost certain that an alien civilization may chart a course, in a way that we can not even fathom, as of yet.

    The emecity of time dictates that any alien species may be millions of years ahead of us, in their development. Being that we have only discovered science in the past 400 years ( yet our grasp of the universe is only about 100 years), and, that our species is hundreds of thousands of years old, It seems crazy to think that we could possibly figure them out.

    BUT! Again I will say, we MUST try!

    Excellent vlog sir.

  6. I think that we should stop wasting money on these type of projects and invest it in projects like a moon or space stations. Let's face it, if we did encounter extraterrestrial life we would only try to steal their resources.

  7. Building bigger and better telescopes is what we should focus on. We will never send a human to another star system so we should just stop putting efforts into that area of science. The only possible way we actually will meet an alien face to face is if Andromeda delivers a life bearing planet close to our solar system. Hopefully we are still here by the time it arrives.

  8. I am not sure how feasable it is, but in terms of finding BioMarkers…adding looking for a high chiral imbalance among asymetrical organic molecules in an atmosphere vs a system's interplanetary medium and sister planets would help.

  9. Hey Fraiser. I never knew much about dark matter so I decided that was the podcast topic I was going to listen to today at work. Upon listening to the podcast, I have come up with a theory that I hope you would read and can tell me if it's possible or not, as I have limited knowledge.

    Here it goes.

    So what I got from the podcast was that the reason the term dark matter exists is because the speed at which masses that are close to the centre of a galaxy is the same as the speed of the masses on the edges of galaxies (same thing for galaxies and galaxy clusters). So my theory is that gravity webs may not have similar shapes for the various sizes of bodies (black hole vs a star). Imagine a gravity web. What if there is kind of like a threshold or barrier in which a body of mass can sink to. And perhaps when larger masses hit the bottom of that barrier, they start to expand outwards. Essentially looking like a vortex for smaller masses with bases that expand as masses get larger (but depth remains the same). This would result in similar gravitational forces experienced by masses that are directly above the bases of the wide bottomed gravity webs which would result in similar speeds of rotation near the centre and at the edges. This would also explain why we didn't detect dark matter in our solar system because our sun being less massive probably would not hit this threshold. I also looked up how they calculate the masses of black holes and the answer was that they analyze only the way in which the surrounding bodies are affected by gravity. And science currently assumes that gravity web shapes are same for all masses.

    I'm not sure if you followed but basically I am hypothesizing that the black holes located at centre of galaxies are much more massive, containing the rest of the masses that "we can't see".

    With my limited knowledge, I am unable to progress from this point and would like to see if someone more knowledgeable can read this and tell me if I'm missing something

  10. what it means is our technology destroys civilisations very quickly so that we don’t get enough opportunity to detect temp civilisations

  11. Its immensely frustrating to know that I have found their signature, but that dogmatic assumptive misunderstandings in physics are obstructing people from seeing it. In fact the relevant data is staring us right in the face.

    The first point is to clear up the physics. Gravity is instant, Einstein's Relativity is sophistry. (Google "instant gravity proof" for the brief – my article should be ranked 1st). So when LIGO detected their signal named GW150914 – it was not a gravitational wave – because that signal moved at light-speed, and thus it must have been electromagnetic.

    I replicated the exact signal in an evolutionary computer algorithm and deduced it was an electromagnetic device that was spinning at a rate that had no less than 5 degrees of acceleration.

    That means its energy was increasing to the power 5. So the acceleration was increasing, as was that rate of increase… etc up to 5 times. Well the details are here (about 50 pages, but some of it has been shortened in the html version) if you can stomach that much reading and the fact that most of cosmology is bad science:
    Try this: http://www.flight-light-and-spin.com/LIGO/analysis-gw150914.htm

  12. Wouldn't it be ironic if whenever we detect intelligent aliens. Every culture we find is so advanced they learned how to not use energy?
    So it turns out our consumption instinct is our cancer of cognition.
    Perhaps their technologies simply completely use energy through all it's cycles. Maybe even they would laugh at us. For our uses of radiation and neglectful drive. To expand our own obvious flaws. Onto the galactic tapestry.

  13. Alone in the Universe? No. Or anyway, not unless it's an artificial universe and creating us really is the reason why it exists. But alone in this galaxy? Even this local group? Probably.

    There's almost no way for a detectable civilization to exist, over long spans of time, without becoming about as detectable as Wrigley field is to a pigeon hatched in a nest under the bleachers. If there were a civilization hundreds of thousands of years old in the Milky way, it would be at MOST of the stars in the Milky way.

  14. If we do find an alien civilization let's prank them. We could send them a message that says "Shut up you fools, they'll hear you."

  15. Question popped into brain: BB theory claims that we started with a period of hyper-inflation, and then I guess it went down to just normal 'speed of light'-ish expansion rate. However, when did 'Dark Energy' kick in to accelerate the expansion? If we started with a very big explosion at around light speed and expansion accelerated for 13 billion years, how come we're not expanding away at way way over 'light-speed' at the moment?

  16. To your final question, I believe optimism is high for such a low probability project, but so much good science and engineering and education will flow from this Quixotic mission who could be against it? When we realise the galaxy is ours to roam we will head out and our life and civilisation will be safe from the Earth.

  17. You won't get a technosignature from an underground civilization.
    Climate Change has nothing to do with finding other technologies unless they compressed
    the Climate Change into days or weeks in lieu of thousands of years like what North America experienced 10,000 years ago with the Ice Age that had a large part of North America covered with an immense glacier.

  18. Another Fantastic Video! ~ With the amount of galaxies, suns, and planets just in the known universe, not to mention the possibility of other universes and/or parallel universes, it seems impossible and almost arrogant to think that we could be the ONLY life forms out there!  The value of the DRAKE EQUATION seems to increase almost daily! ~ It boggles the mind to think about!

  19. I love this topic, however i feel that we may be wasting our time looking for intelligent life on other planets. I say this with the most respect and i prey that i am proven very wrong one day. i base my statement on the only evidence of intelligent life that we know of in the Universe and that is us. We have come so far in such a short period of time and i strongly believe that we would need improbable timing to find another intelligent life form, equal or better than us . I am of course basing this on the fact that we have only been visible to the rest of the universe for a very short period of time. Taking into account the age of the universe and the incredible global events that have occurred over the last few billion years, i would say that intelligent life would be very rare in the universe. However i strongly believe that complex life forms do definitely exist and probably very plentiful.

  20. Hey fraiser, quick question. I've always thought the universe as a recycling one. We see it in everything observable, from life, stars, galaxies, and many more examples. Why is there not a hypothesis reflecting that regarding how it universe operates? The closest thing I have found is "the big bounce" idea, but that is dismissed by most theorist. I am obviously missing something, but I am still curious as to why since we seem to base our ideas off of those things observable. Thanks for your time, I love your channel! 😁

  21. One Question:
    Would radiosignals from far away (even in our galaxy) not be too weak for our teleskop to detect?
    I mean, the signal gets weaker and weaker proportional to the distance it travels.

    We have also to consider that aliens, more advanced as we are, use other technology than radiosignals. They are too slow for interstellar communication. Who knows what technology is possible.
    We are just in the beginning of science. We should not be so sure to say what is possible and what not.

  22. It is impossible to have even the remotest
    chance of tracking down an alien civilization
    with the help of Technosignature. Even with
    a time difference of only 1,000 years of
    technical development between two somewhat
    similar civilizations, the junior partner can no
    longer see the other side.

    Then the physical bases used by each of the
    two are incompatible for this purpose.

  23. All this is very much assuming a civilisation that is increasingly materialistic / expansive. If spiritual / psychologically motivated, then an advanced civilisation might use less and less energy as it progresses – and may even have cleaned its planet up!!. Just a thought. What we look for then? They may be invisible, after learning about the destruction an expansionist policy. Perhaps we should be looking for telescopes!?

  24. Hi Fraser, first of all thank you for all your work. I have been a viewer for some time now but only got around to subscribe for the newsletter last week. I didn't receive any email on Friday as it is scheduled. I was wondering if there is some issue with my subscription.

  25. Hi, Fraser, I have a question for your next Question Show: Why ion engines aren't used on the ISS to maintain the height of its orbit? Shouldn't it be more economical than using standard fuel?

  26. In the end its all about time, we are looking at such a tiny time frame that it's almost impossible to find anything far away. There is plenty of life all over, but the admin of this universe has designed in a way that light/radio induction moves very slow, and life is designed very very small, making distance huge. If light was million times faster, then you might find something. Is something smart enough to overcome the time and distance issue? Perhaps there are many secrets of physics we have not found yet for sure.

  27. Hello! My question to you is as follows, If space is continiosly expanding, how come Andromeda is on a colision course with the Milkyway? Wouldnt space expand in a rate that eventually Andromeda would start to move away from us?
    Anyways thanks for great content!

  28. When you think of the trillions of stars and galaxies out there (i.e. potential for intelligent life), how brief our lives are, and how seemingly futile space exploration is, are you also overcome by a heavy sadness as I am?

  29. I have two questions:

    Given that Pluto and Charon are tidally locked together does that mean that a cable could be strung between them so that explorers could get from one to the other on an electric cable car?

    Probes to Pluto travel so fast that they get hardly any time to explore it as they shoot past. Would it be possible to snare them with a skyhook anchored to the Pluto-Charon system?

    I believe that the answers to both questions are "yes." Indeed, if the mutual orbit of Pluto and Charon is a bit elliptical then it should be possible to generate electric power as the cable is let out from a reel up to apoapsis and then reeled in up to periapsis. As for the Skyhook idea: Since we know how fast New Horizons is moving and can estimate the tensile strength of the cable it should be possible to calculate the minimum length of the Skyhook's cable (the longer it is the lower the deceleration required to force the probe to travel in a circle). The skyhook's cable might be attached at a right-angle to the center of a cable running between Pluto and Charon, with a swivel or bearing at the attachment point so that the skyhook can rotate around the cable between Pluto and Charon without getting tangled up. Note that the probe's kinetic energy is still the same but the probe is simply orbiting the system on the end of a cable. Then, when the probe has had a sufficient time to carry out its mission it can be released from the skyhook to fly off in the desired direction to reach another body including sending it back to Earth.

    Of course, if you have a skyhook such as this installed there already then that implies you have a (perhaps robotic) base there and the two planetoids have already been explored. So it would serve as a way-station or hub for travel within the Kuiper Belt allowing ships to change direction without expending any delta-v.

  30. Fraser: Could you do a video on which stars are about to go nova, where they are, how bright would they get in our sky and for how long they would be unusually bright? How long ago they would have actually exploded if the light reaches us tomorrow? maybe talk to some of your astro-celebrity guests and make a star "dead-pool" find out everyone's top pick for the next star death. That would be awesome.

  31. If the expansion of the universe gets faster the further you go eventually becoming faster than the speed of light, if time stops at the speed of light then reverses faster than light speed that would mean that the space at the edge of the universe is essentially going back in time….following this reasoning wouldn't this lead you to the beginning of time again, ie keep going past the edge of the universe faster than light and you would get to the big bang. Big bang would be at the start and end of universe simultaneously. Like the universe is the sphere and you start with a big bang at the pole expand until you get past light speed then somehow you end up going back inside towards the singularity. It would be different to the big bang then big crunch because time would be reversing not gravity…..my question is do you know of any obvious flaws in this ?

  32. i'm noticing an increased use of the word "gold standard" in the science community. some things just come in and out of fashion i guess.

    so we are looking for lasers under our lamppost now. which makes sense, as we are planning to use similar space technologies ourselves. the problem is that we're still only looking under our lamppost.

    i'm afraid the answer is somewhere else, in between the lamps, shrouded in utter darkness.

  33. Why does everyone always use those quotes from Arthur C. Clarke? Seriously? No one ever uses his quote: "The" anymore!
    Or the quote: "At"
    Or my personal favourite Arthur C. Clarke quote: "When"

  34. How do scientists clean those large telescope mirrors or lenses of dust and debris without damaging them? Do they have special tools or cleaning solutions?

  35. We are lit up like a roman candle with our current technology so it would be very easy for anyone out there to see us if they are looking. But in the grand scheme of things we will only be broadcasting for a very short amount of time. Within a few hundred years or less we will either have scaled back to a more simple time before technology, wiped ourselves out, or advanced enough to be using some type of quantum entanglement for communication. Whichever way we end up, we will have mostly gone dark by then. So if we are referencing ourselves as a starting point for the search then chances of us finding anything is slim to none.

  36. I don’t think you’ll get an answer to that question if the answer is no.
    If there are civilisations out there then eventually with the right technology we will be able to find them. We only need to find one civilisation to answer the question ‘Are we alone?’. But if there are none, then we will only know that when we have searched every single planet around every single star. Finding the answer ‘no’ will take a lot longer than finding the answer ‘yes’.

  37. What is it really going to take us Define if there's life out there or not. I hope we find out either way in my lifetime.

  38. Got a question it's not about this video if we are moving expanding what are we expanded into. And all their stars and planets in every direction of the Earth.

  39. Tau Sagittariiis thought to be the likely source of the Wow signal, if it was even really a genuine signal. That star is roughly 125 light years away, so if we even knew for a fact the system was emitting artificial signals and somehow found a continuous signal from there we're unlikely to ever be able to physically visit it unless there's some kind of hyper-warp drive invented. Maybe it was those guys testing some kind of ultra-high radio energy device/weapon that was powerful enough for us to detect, but destroyed their whole civilization on testing, and we just happened to be lucky enough to catch the final 'pop'.

  40. Look for sparkles around a star, at planetary distances. Spsrkles would result from any visible light emissions from thrusters, comm lasers, space pollution cleanup tools, etc. This would require fast photosensitivity, and maybe we won't have anything powerful enough for a few more decades.

  41. Question
    I wonder about larger planets with two to three times the Earth's mass being better suited for life. With the much larger gravity well, do you think that intelligent life would struggle to get off their planet, let alone make a noticable presence in space we could see?
    Maybe we're just lucky to live on a small world.

  42. Before I started watching these astronomy videos on YT, I had ideas of a big Star Trek-esque galaxy filled with humanoid intelligence. Now I find myself drawing closer and closer toward the, ugh… "rare earth" theory. It kinda sucks, because I'd wish they'd find something interesting through the RTs to give us some hope. It sure looks deserted and boring out there though.

  43. I'm curious as to how much material would be needed to construct a Dyson Sphere. In my mind I imaging there would not be enough material, much less useful material in our solar system to make one.

  44. Atheists believe there's no God because they never see God.

    But those hypocrites also believe in alien life even though they never see an Alien.

    Atheists demand "a picture of God" to prove God existence.

    But they can't give us "a single picture of alien" to prove alien life.

  45. We are so sure higher civilizations are talking by electromagnetic waves. Ancient Sumerians considered it by blowing horns… We are so pathetic…

  46. I sometimes listen at night for aliens using megaphones on very high mountains on other planets. So far, nothing.

  47. They're out there. It's just a question of how frequently, on what level of development and whether such civilizations can stand the test of time. Then there's the nightmare scenario of an uncaring machine civilization like something out of Star Trek. If there are existing technical civilizations in our galaxy, I frankly hope they're a long way off. We have enough internal worries right now without that sort of complication!

  48. NASA could be getting telephone calls from ET 5 times a day and they still wouldn't tell us. They would say something cute like it was a kid in WI breathing too much swamp gas. NASA-never a straight answer.

  49. I always thought that because of the inverse square law, that it wouldn't matter how big our receivers were, because the leaked signals from a civilization like earth, would be indistinguishable from background noise. is that not the case?

  50. Maybe any alian civilizations have not advanced at all. They could be out there still rubbing sticks together to make fire.

  51. i wonder if the public would be told and what we would do if we were able to communicate suddenly with another species; what if they then said, "please prepare to be extinguished; you have 10 of your Earth years."
    when they arrived we would watch as they treated us the same exact way we have been treating animals here… we would see their tv signals broadcasting cooking shows on how to fillet humans and watch as they gutted each of us with some gnarly set of tools in casual disregard. "you can then grind the children up very fine and add water to make red dye for clothing." live humans thrown in a giant mortar and seeing a pestle get to grinding "…for those of you with sensitive hearing, simply shove some cotton plant down the throats to stop the screaming… alternatively one can fork the throat of the human and twist until hearing a pop"
    people in your pen, along side you, would be walking around looking like monstrously overgrown bodybuilders due to the massive amounts of hormones being pumped into them to promote meat growth.

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