Looking For Extraterrestrials Looking At Us

[/caption]The cosmos is a very big place, how do you begin the search for exoplanets orbiting other stars? Astronomers have a few tricks up their sleeves to work out how to spot these tiny specks of distant alien worlds. Astronomers can look for the gravitational “wobble” of a star as a massive exoplanet tugs on its parent star during orbit, or more commonly, they look for the slight dimming of star light as the exoplanet passes in front of the star. In fact, the Kepler space telescope is going to peer into space, surveying 100,000 stars to do just this; not looking for large gas giants, but detecting rocky bodies that resemble large Earths with the unparalleled precision.

OK, so we have a means of finding these habitable worlds, how can we use this information to widen our search for extraterrestrial intelligence? Researchers in Israel have asked that same question, and arrived at a very logical answer. If we are to communicate with these advanced beings, perhaps we should make sure they can see us first…

The concept is simple enough. Find a star with an Earth-like transiting exoplanet (we will hopefully have a few super-Earth targets over the next three years with Kepler), aim a radio transmitter at the star and send a “Hello world!” message to the possible alien civilization living on the exoplanet. All going well (or not, depending on whether these extraterrestrials are actually friendly), we’ll get a reply from said star system in a few decades with a message saying something like “Hello world to you too!”. It would be a momentous day for interstellar communications and it would answer the one question that bugs astronomers everywhere: Are we alone in the cosmos?

So far so good, until interstellar travel becomes a reality, mankind and our new chatty alien neighbours can play a very long game of radio tag, learning more about each other as the years/decades/centuries go on (depending on how distant the extraterrestrial civilization is in the first place). But there’s a problem with this plan. What if our ET neighbours aren’t looking in our direction? What if the Sun looks like ‘just another’ star amongst the other 1010 Sun-like stars hanging out in the Milky Way? We can transmit to our hearts content, but they may never see us.

Shmuel Nussinov at Tel Aviv University in Israel asked these same questions and actually makes the search for extraterrestrial intelligence a little bit easier. With the assumption that a sufficiently advanced alien race is surveying the skies, also looking out for exoplanets orbiting other stars, they may be using the same transit method that we use to detect exoplanets. Therefore, it only seems reasonable that ET will only be able to detect Earth if we pass in front of the Sun, thus dimming it slightly for our alien neighbours to see us. If this is the case, it seems highly unlikely that any alien race will detect our existence unless they are located along a narrow angle along the ecliptic plane of our Solar System. So, if we want to open up some alien banter, we should perhaps send signals to Earth-like exoplanets spotted along the ecliptic.

Although the Earth only passes across the solar disk for 13 hours every year (as viewed by a distant observer), our star will appear to dim slightly, allowing ET to see us. Factor in the various transits of the inner Solar System planets, and our observers will see there are a few possibly habitable rocky “exoplanets” for them to transmit to. If we are already transmitting, communications can be exchanged.

What a good idea

Source: arXiv blog

58 Replies to “Looking For Extraterrestrials Looking At Us”

  1. We must seek ET’s. Why? From ET’s we could receive the very valuable information. For example it could be a new superbomb design.

  2. The extraterrestrials can destroy the humans very and very easy. How is it possible? They could give us information which will bring humans to self-destruction.

  3. As I understand it the next generation of telescopes should be able to capture images of earth sized exoplanets. If this is the case then current detection techniques will have have a short life span.

    What are the chances of aliens being at a similar technological stage?

  4. let me see – speed of light communications…..sorry, I don’t have the decades….more likely centuries, to wait. I’m glad the SETI folks employ some microbiologists. I’ve never met an intelligent microbe, but at least we should be able to find them a mere 35 million miles away on Mars. If we can’t even do that, this other stuff is a waste of time.

    Heck, we’re not even sure if the drops that formed on Phoenix leg after landing are water or not? Pathetic. And we’re supposed to signal intelligent life light years away? We’d probably kill them when they saw how “intelligent” we were – they’d die laughing.

  5. Why bother? If the movie Contact taught me anything, it’s that we’ve been saying ‘Hello’ to the universe since the advent of mass radio/television. Aiming a radio transmitter at a star seems redundant since transmissions from the 1960s have a 40 year head start.

  6. I have said it before and I shall say it again. Leave all the searching the stars for another generation, leave all the probes sent to the various moons, asteroids etc of the solar system for another time. Let us concentrate on using all of our resources on getting to and settling the Moon and Mars. We as humans need to do this. After this, we will have a base in our solar system and we shall be then far more technically advanced. Then using what we have learned, we should then prepare ourselves for the next steps in stellar exploration. We humans do not have an overall plan, it is about time we did. Who agrees? Roger

  7. Shouldn’t we be targeting the swath of space upon which Jupiter plants it’s Sol-generated shadow? Yeah, Jupiter wouldn’t look a lot like home to fellow terran-based extraterrestrials, but it’d sure be a lot more noticeable in the wobble-o-meter, and potentially in the transient-seeking followup measurements.

  8. What a bunch of pessimists and me-firsters here.

    Your future will never happen because you can’t think outside your little immediate boxes.

    SETI is inexpensive and if someone wants to do it, so long as you aren’t involved, what do you care?

    Just stay out of the way for those who will reap the true rewards someday because they thought past the next election.

    The meek shall indeed inherit the earth – the rest of us are going to the stars.

  9. We are like a little lamb in a forrest making lots of noise without having a clue what is out there. Maybe we should stay quiet, develop, explore our own solar system, and develop techniques to actually find out what is out there before broadcasting our presence to anything that happens to be there. We have no guarantee that we won’t get the notice of a predator we can’t handle as opposed to some nice feely new age type friendly we all love each other civilization … I think it’s blind stupidity to just go ahead and broadcast our location without knowing anything about what is actually out there, and I’m not surprised we are going ahead and doing it anyway.

  10. Let us concentrate on using all of our resources on getting to and settling the Moon and Mars. We as humans need to do this

    …many would view this as being narrow minded. I have to agree. To increase our knowledge of the cosmos, we need to pursue many facets. Not just a couple near by missions.

    Think how much more ignorant we would be if all we have done these past 200 years is focus our telescopes only on the moon or Mars. We definitely wouldn’t have more than one type of propulsion system, and other technologies wouldn’t have been discovered or needed.
    To make the argument we would have colonized the moon or Mars by now wouldn’t hold water. We barely have the technology and resources to do so now. With less knowledge, we would have only been spinning our wheels.

  11. Too late, Just like Ron Dwyer Says we have been doing that for some time. Now depending how lucky we are, if aggressive aliens intercept our signal and pin point our location and decide travel to our solar system, that means they are by far more advanced than us. Good luck, I hope the UN will try to calm them down. The good news for some of us we get to interstellar travel to other worlds as slaves or dinner 🙂
    Another scenario is that aliens are sending us a signal using different method something that we have not yet discovered. All this is very fascinating, keep up the search.


  12. For those who are worried about other life forms coming here to eliminate us.

    First of all… quit being a wuss. If they have the technology to come here, then they have the technology to find other Earth like planets which are uninhabited so they wouldn’t have to deal with a risky fight, and half the resources haven’t been used up.

    Second… if they are that advanced, then their life forms are likely peaceful. Civilizations which are greedy and war mongering don’t last a long time, and they tend to move backwards not forwards…. and this is even if they survive one another. I’m not sure the people of Earth are peaceful enough to gain the knowlege required for interstellar travel before we blow each other up with nuclear or chemical weapons.

    Third… the technology and knowledge we could gain definitely outweighs many of the risks involved.

  13. Folks – there is a good chance that our signals have made it the 50 light years that is suggested – there is also a good chance that those very signals have been scrambled into static before hitting the nearest star, too. We don’t know.

  14. I think SETI has the right idea, at least for aliens civilizations out there that might be transmitting in a way that’s applicable for us to receive their signals.

    However, what if there are not that many civilizations sending those kinds of signals. It would be the equivalent of a lone person shouting to you from the other side of a crowded football stand. And unless there’s a way to systematically hone in on the broadcast, much like SWIFT hones in on GRBs, or perhaps, cancel out static noise, the chances of picking up few signals, will take an extremely long time to discover.

    Or maybe this is the norm, that aliens, after reaching a certain technological level, eventually use this method, so the chances of a signal being picked up increases.

    On the other hand, we might just be existing in the midst of a symphony of various kinds of signals being sent our way, and we either are not currently looking in the right direction, or, don’t yet have the technological means to recognize any of it.

    SETI is a great start, but there should be various kinds of SETIs focused on the same objective, using different techniques.

  15. It seems almost absurd to think that we have much to offer an alien species with regard to a mutually beneficial relationship.

    The perils would be encountering another species that is vastly advanced, and therefor has no interest in communicating with us or a civilization that is on a similar level developmentally, and we can see pretty clearly that we’re a chaotic disorganized mob.

    We won’t be communicating with a less advanced civilization anytime soon since we’re at the lower end of the communication scale now.

    How would the Human Race Fare if it encountered another Human Race, possibly one with a technological advantage? I think it’s in our best interest to just sit back, shut up and listen for a while.

  16. What if they aren’t friendly?
    Noone asks the simplest questions anymore. If were to find a planet dominated by chickens,cows and fish we would love it right? because those are things we eat. Now on the other hand what if we find a sentient carnivorous species very intelligent basically in step with us. Then what? do we communicate even though we could be lunch..

  17. For those of you who say we should keep quiet until we know who or what is out there in the galaxy – you are right.

    For those who say it is too late, we have already broadcast our presence into the galaxy for the last century (thereby making a bubble of electromagneitc waves 200 light years around) – you are also right.

    But guess what – there will be humans (or at least our descendants) going into the galaxy no matter what anybody says. There will always be humans who want to explore new frontiers. There will also be humans who are unhappy with life here and want to make a new home elsewhere. And there will be criminal types and corporations (sorry, just repeated myself there) who want to escape and be free to do their business out of the reach of Earth and the Solar System.

    There will also be those (and are) who broadcast into the galaxy despite any warning or law trying to stop them.

    In other words, humanity will be doing what every other living thing has done on this planet for over 3 billion years: Expanding into new territories and encountering whatever organisms are there.

    We may come out on top, we may make new friends, we may be ignored, we may be enslaved, or we may be destroyed. But we are going into the galaxy some day. It cannot be stopped other than with the extinction of our species before we start colonizing. And I doubt we are the only species in the Universe who feels and acts this way.

    So stop whimpering under your beds and get out there! Because if we remain ignorant of what is in the wider galaxy out of fear, chances are pretty good our ignorance will come back to bite us, literally.

  18. >We must seek ET’s. Why? From ET’s we could receive the very valuable information. For example it could be a new superbomb design.

    Thank you. This gave me quite a chuckle.
    I like the way you think!

  19. The Earth only passes across the solar disk for 13 hours every year right. But what about the other plantes specialy Jupiter. If someone is looking at our Sun Im pretty sure that they’ve noticed that our Sun dims a lot because of all the planets.

  20. bopjazz Says:

    March 13th, 2009 at 9:24 am

    >We must seek ET’s. Why? From ET’s we could receive the very valuable information. For example it could be a new superbomb design.

    “Thank you. This gave me quite a chuckle.
    I like the way you think!”

    This kind of paranoid, primitive thinking is why we have not found ETI yet. Nor will we until our species either grows up or is replaced by something much better.

  21. Any civilization with sufficient technology (say, a few hundred years or more in advance of our own) is not going to be looking for wobbles in our star, it’s going to be looking directly at us in very high definition. But that assumes we’re dealing with humans on another planet, which will not be the case.

    It’s a mistake I think to form our ideas about life in the universe on anthropomorphic principles. Life is not going to be like us. You don’t see dolphins developing radios or telescopes. Elephants aren’t building rockets.

    I think it’s fun to look for life out there, and it will be there, everywhere, but we still do not have sufficient grasp of what life actually is. This becomes very clear when these stories and comments are dissected and one sees that we’re expecting to find ourselves out there, which is plain simple-minded. It’s not going to happen. We will not be able to communicate with the life we find. It will not have metal ships and radio telescopes, nor will it understand binary code. Its “technology” will not be recognizable to us, nor ours to it.

  22. Dude, even my 8 year old cousin knows that “WE NEED TO SEND THEM MSG SO WE CAN COMMUNICATE”.

    Seriously Ian, this is the most amateurist idea EVER.

    WTF ??!! Hahaha. This should totally BE ON THE FAILBLOG !!

  23. Some of these commenters seem to be firm supporters of WETI… as in “I weti my pantsi in fear of Bug Eyed Monsters out theri”.


  24. @Bikks, and you have obviously no clue about how close an intelligent civilization can be.

    Also, I’m not from SETI but I hate a several pussies and pessimists on here.

  25. To the scared lot and pessimists:

    We must ask ourselves what we would do if we had the interstellar traveling technology? Are we going to spend trillions to go to a planet (say 20 light years away) just to pickup chickens and cows? Even if we find a planet full of diamonds, are we going to spend trillions to pickup a few pounds of diamonds? There has to be a commercial sense for the ET to spend trillions to come to earth and it cannot be based on just exploitation of living creatures of this planet.

    Those civilizations having interstellar technology would have built better robots than the lazy humans they are feared to enslave. If they just come here to eat us would also not make any commercial sense, they would have mastered the production of tastiest food in their own backyard. What great do we have to offer to the ET that they may not have in their own planet other than plane simple exploration of a new world?

    If they come to us just to destroy our world and get the sadistic pleasure out of it then they would not have reached interstellar travel technology in the first place.

    To the optimists:

    Switching on the radio and television station during the middle of the last century means nothing. We have not sent any directional signal and therefore what we are presuming to have been sent earlier is already submerged in the static and cannot be picked up. Unless we make a concerted effort no contact can be made with an equal or marginally advanced civilization.

    Those people who think Jupiter is easier to detect considering its 12 year revolution and thinking that it lies in a different ecliptic plane, I would suggest them better reading.

    Those who think the ETs have far better imaging technology than us then it would be worthwhile to send signals perpendicular to the ecliptic rather than parallel to it so that they can mask the sun and directly image the orbiting planets.

  26. @headaroundU
    Dude, there are only about 100 stars within 25 lightyears from earth, with only a very small number of exoplanets found so far

    Sure,you could be lucky, but if you want to have a reasonable chance of encountering an exoplanet that can potentially harbour intelligent life, you probably need to search tens of thousands of them. This means you will have to look at an even larger number of stars, which means you would need to be looking at much farther distances. Our galaxy alone is 100.000 lightyears wide. It does have 2 bln stars, so there is a good chance some have life, but radiowaves will also take thousands of years to reach them and get back to us.

  27. “We are like a little lamb in a forrest making lots of noise without having a clue what is out there.”

    I agree, lets dig a deep cave and hide in there for the next 200 years or so. pretending that nothing is out there. Living in fear that they might find us one day.

    With this kind of mentality, Columbus would never have dared to go out and search for another route afraid because there might be somehing out there that we do not know what it is. Scaaaarryyyyyy…….

  28. Isn’t there a lot of evidence they are already visiting us?
    Or do we believe we are the first who will make interstellar travel a reality?
    Or do we believe we are dignified to be contacted? (And so that our wars, planet exhausting, other countless behaviours are completely alright?)

  29. If ET’s are like us then we are in grave danger, we are a violent and extremely dangerous species, if they are not like us what makes us believe that they would want to contact such a barbaric species as us ?

  30. Hi,
    If we find that there are more habitable worlds out there, this may give a clue on the likeliness of possible extraterrestrian life. But finding worlds with possible extraterrestrian life does not necessarily mean that all these worlds are currently inhabited by space-travelling civilizations, curious and eager to conquer and enslave us,or to aid us, or to learn from us. If someone lives somewhere this does not neccessarily mean that he or she is interested in what is the heavens above.

    Perception is a matter of the perceptional horizon offered by the concurrent culture.
    At the times of Galileo Galilei, telescopes were known, but rarely used. At that time nobody spent just a second to consider whether there was any use to look at the moon through a telescope. The accustomed way of studying the moon then was to go to a library and read what information was available in books on the moon. Finding out about things by experiment and by one´s own experience and thinking was considered an unscientific approach, and quite dangerous. Galileo Galilei was among the first to change this, and it almost cost him his life.

    We may be proud of the technology we developed and the possibilities and knowledge it offers to us, and we are perhaps begging for some kind of recognition from other alien civilizations. We hope that our kind is not the only such one, and we hope to be recognized by someone out there as something of importance.

    However, the stars don´t care. The importance we may have is confined to us.



  31. “With this kind of mentality, Columbus would never have dared to go out and search for another route afraid because there might be somehing out there that we do not know what it is. Scaaaarryyyyyy…….”

    Ahem, Columbus was not afraid…he knew there was land to the west….he had maps for pete’s sake…courtesy of the great Chinese fleet which circumnavigated the globe from 1421-1423

    Sorry, I just had to!

    Anyways I think we should do everything we can to get out “there”. Whether it be colonizing other planets to sending radio waves to other solar systems or just listening. It needs to be done!

    I believe we should send thousands/millions/billions of messages….one per star system…or even multiple.

    This is Earth! Hear me ROAR!

  32. Yes, “they” will most likely look exactly like us, their machines will be made of metal, and they will use radio waves. To say otherwise is to be projecting very strange ideas that the rest of the universe is not made of the same materials with the same properties, but it is. It’s all the same stuff as right here at home. Sure there could be extreme exceptions, but if we are a good general example of life, then so will be most of the others. I predict humanoid bipedals with automobiles, rockets, economies and politics. Images of bug-eyed monsters is pure fantasy. Besides, the most bizarrely imaginable life forms already exist right here on Earth: insects, fish, snakes, lizards, ostriches, kangaroos, giraffes, etc. We are already living in a universal microcosm. These same forms will be found on all other “earths”. The only major difference in form might come from less or more gravity. The laws of nature are universal – they don’t change when we leave Earth.

  33. “I agree, lets dig a deep cave and hide in there for the next 200 years or so. pretending that nothing is out there. Living in fear that they might find us one day.”

    You go right ahead and do that ..

    But my point (if you can actually read) was lets watch and listen for a while before broadcasting … develop technology, move into our own solar system. I never said anything about hiding in a cave or anything about bug eyed monsters. I would just err on the side of caution since at the moment we have literally no information about what is or is not out there since we don’t have a clue. We could be alone, but let’s do all we can to find out. If we find some friendly aliens to talk to, great, if we don’t, thats great too. But let’s find them first, then talk, rather than just sending out a bunch of please find me new age feel good messages to a universe that at its best, probably doesn’t care…and if there are advanced races close enough to us the hear those messages, they probably know we are here and aren’t talking to us for a good reason … we would attack them on sight, if we haven’t already.

    And who would want anything to do with a race that destroys itself and everything in its path, including it’s own planet? I wouldn’t go anywhere near them and definitely wouldn’t given them any advanced technology so they could spread their cancer throughout the galaxy, which is actually their goal. They’ve destroyed their own planet and are now looking for others to “colonize”.

    To all those who think all intelligent races have to be friendly, where do you get that information from? Our one example? LOL.

  34. The universe is most likely bubbling with staggering number of life forms. A tiny fraction may be intelligent and even a tinier fraction may even be more intelligent than our species. It is doubtful that intelligent species will ever communicate with one another. I suspect the cosmic distances between communication capable intelligent species is entirely too vast and number of capable species too rare. A focused radio frequency communication at any unimaginable power level literally fades to nothing detectable after a light year or two of travel. The signal to cosmic noise ratio is impossible. A little like the light from a ‘burning candle’ on the surface of a star getting mixed with the light of the star. It simply can’t be done. On the subject of man traveling to the ‘stars’, that will not happen for centuries; if it ever happens. Man is entirely too fragile for multi-generation deep space travel. Man will make it to Pluto and .maybe a bit beyond, but , no further. Mankind will never leave the influence of the Sun unless some means to travel faster than light is discovered. .

  35. I got sick of reading all that jibber jabber. (comments)

    On the other hand the idea in the article seems logical, its all these little things we have to think off, to put ourselves in ET’s perpective.

  36. I’m confused. Why should we bet the whole farm that the intentions of any alien civilization are benign? There’s no evidence to support that bet. The whole point of an alien psychology is that it will be *alien to our way of thinking.*

    If we contact an alien intelligence with a bright neon sign saying “we’re right here, come say hello,” several possibilities occur, many of them bad.

    A) They don’t hear us.
    B) They hear us, but don’t care.
    C) They become our super-galactic best friends and send us all kinds of cool technology via laser or radio beacons.
    D) They regard as an abomination that must be destroyed at all costs.
    E) They decide to send us super cool communications that are intentionally/unintentionally infested with very sophisticated trojan horses, viruses, etc.

    It seems to be a default assumption among many SETI folks that any intelligence we contact will be “advanced” by our definition of advanced.

    Again, I see no evidence for that assertion, merely a quasi-religious faith.

  37. “It seems to be a default assumption among many SETI folks that any intelligence we contact will be “advanced” by our definition of advanced”

    They have to be advanced! We just barely scratched the understanding of the universe. If they can detect us either they are extremely lucky or are a bit more advanced than us with their detection equipment.

  38. “It’s a mistake I think to form our ideas about life in the universe on anthropomorphic principles. Life is not going to be like us. You don’t see dolphins developing radios or telescopes. Elephants aren’t building rockets.”

    How do you know that they wouldn’t if they could? If you have no hands, no opposable thumbs, no mastery of fire, you have no spacefaring technology, no matter how smart or linguistic you otherwise are.

    Don’t confuse physical cability (even though dolphins and elephants *have* been observed doing crude tool use) with intelligence or behavorial differences. I doubt they think we aren’t sentient because we can’t hear (what we consider) ultrasound or infrasound….

    It’s not anthropomorphic to realize that technological civilizations *must* have *some* things in common.

  39. Uh…we have been broadcasting our world for quite a while now. Initially with radio, television, surface atom bomb blasts….etc. How will an extraterrestrial winnow through that and find what the scientists want them to find. Well, if anything, we are entertaining.

  40. Oh, I think Earth will be very interesting…we have a lot of heavy metals, a en sitio population and a paranoia mindset that would be easy to manipulate…what’s not to like? The options are limitless….

  41. send all of the messages SETI wants, It is just a waste of resources, There is no-one out there to listen anyway. We are alone and the universe is waiting for us. It is our destiny. We have to start somewhere so lets get on with the Mars job. Roger.

  42. KevinM:

    you just wrote one of the most plausible, sensible and down to Earth assessments of hypothetical alien life I saw.

    “The laws of nature … don’t change when we leave Earth”

    You nailed it!!!

    Mind you, “they” could look strange (to us), due to environmental conditioning…. like a 1 metre tall conical with a 1 metre base width, from a World four times as massive as Earth… but he still might fall in love with a girl from Ireland….. their DNA would be nearly identical.

    Alas, no proof, but life seems to get started quite easily, it seems to be quite tough, and the ingredients are there, throughout the Universe – and the principles of how it all works are the same everywhere.

  43. I think that it is quite possible that there is life out there. To think that we are alone in this universe is like the time that we thought that there is nothing smaller than an atom. I think the question here is not “Is there life in space?” but rather “When/how/where can we meet our neighbors?”

  44. @Olaf:
    “They have to be advanced! We just barely scratched the understanding of the universe. If they can detect us either they are extremely lucky or are a bit more advanced than us with their detection equipment.”

    They also will have much different motivations and psychology. We tend to associate “advanced” with “peaceful” and “compassionate.”

    Why would that be true of alien races?

    Show your work.

  45. I believe that most advanced civilizations/ life forms would be so advanced that if they had the capability to detect us we would be like ants to them, a curiosity but not worthy of communication. What would they gain?

    Plus any advanced life form would be concerned that inadvertent communication might alter our evolutionary process. In other words, we need to demonstrate our ability on the universal stage that we are grown up enough to be an intelligence worthy of folding into the fraternity of higher life forms.

  46. A more advanced intelligent life form could have developed somewhere in the universe a billion years ago. So where are they? We have a nice blue planet with ideal living conditions and yet the aliens are absent. We humans will solve the problems of space distance within the next thousand years for sure, Intelligent aliens were they around should have solved this problem a billion years ago and yet they are absent on our planet. Conclusion, there are no intelligent aliens out there, we are the only ones. An unplanned fluke in the Cosmos which took four billion years to develop and most of that development within the last five thousand years. We are alone friends, get used to it.

  47. “A more advanced intelligent life form could have developed somewhere in the universe a billion years ago. So where are they?”

    There are many possble answers here, and absence of evidence does not necessarily imply they do/did not exist. It just means we haven’t found any evidence, it does not mean there is no evidence to find.

    “Conclusion, there are no intelligent aliens out there, we are the only ones.”

    Reaching that conclusion based on no evidence just means it is the conclusion you wish to be true … for whatever reason. It is not based on any facts, since the only fact we have is they are not here … and that might not even be a fact. What if they were/are here and we either don’t recognize them, can’t see them, ignore them, ridicule anyone who does see them … is that a possibility? I think it is.

    In the end you could be right, but why conclude that now? Its a conclusion based on lack of knowledge and is merely a belief at this point. Why reach that conclusion?

    Remember, 20 years ago some scientists didn’t think there were any other planets out there, now most think that every star probably has more than one. Those scientists who thought there weren’t any were coming to conclusions based on lack of knowledge. Those kinds of conclusions almost always turn out to be wrong.

  48. This notion that we’ve been spewing out radio signals for 50 years or more, thus announcing our presence, still persists. It is false. All terrestrial transmissions are unfocused and low in power. Any leakage wouldn’t make it out of the solar system, let alone to the nearest star system.

    As for finding other technological intelligences, the chances are practically zero. Not only would they have to exist, but they would have to exist at the same time as we do (whatever ‘same time’ means across lightyears of space). Given the age pf the galaxy and assuming civilisations last for, to be generous, a million years or so, then the odds of finding them and finding them while they’re still around, is negligible.

    I’m sure that basic life exists in great number, but that is no guarantee that it will develop into a technologically capable civilization. Humans evolved by chance – there was nothing pre-destined about it. Life on this planet was perfectly happy to exist in single celled form for some 3 billion years (1/4 the age of the Universe), before making the leap to multicellular complexity, and that step need not have happened.

    Even after 500 million years of animal evolution, we would not be here if the dinosaurs didn’t go extinct and a new niche opened up for other life forms to exploit. And even when humans did evolve, not all were technology based. for example, nomadic peoples like Australian Aborigines and others, were perfectly happy without building skyscrapers, planes and cell phones.

    So, the odds are practically zero that we’d find any intelligent, technology based life out there.

  49. Yes indeed it would be wonderful to learn that there was intelligent life somewhere out there in the universe. Humans have only had the technology to search for other life forms in the universe for 50 years or less. Perhaps we give ourselves too much credit as being an advanced species. Surely there must be other far more advanced forms of life out there somewhere.
    And I must agree with the writer who compares us to ants. Ants hardly notice us and cannot possibly comprehend the actions of homo sapians.
    We are only at the begining of our learning curve of the universe. Perhaps one of these days in the distant future, (millions of years is but a blink of time) we will be invited into the club.
    Perhaps when we understand- dark matter- dark energy-black holes- gravity- singularities……..
    Welcome humans!

  50. “We have a nice blue planet with ideal living conditions and yet the aliens are absent. ”

    On the assumption that that’s what they’re interested in (even if they started on a similar ‘blue planet’ themselves) or that their existence would be obvious.

    Any civilization we encounter will almost certainly be seriously older than our own (because one seriously younger will obviously not have interstellar travel, nor be detectable over interstellar distances). This isn’t just a matter of estimating *alien* motivations and psychologies, it’s also determining what a civilization *millions of years old* will be like.

    That’s a question we can’t really even answer for ourselves, looking just a few *centuries* ahead…

  51. They also will have much different motivations and psychology. We tend to associate “advanced” with “peaceful” and “compassionate.”

    Yes, not foolishly though. All intelligent species will have to have taught their young and therefore be both nurturing and empathic. You can’t build technology when you don’t have good communication, cooperation and a working system. You also have to wonder and reward curiosity to achieve an interest and accessibility of space. These traights make it impossible for some violence oriented, dangerous alien race to make it here in search of loot. That’s just the usual, rather sad paranoia that keeps humans from our potential.

  52. Actually, it boils down to 2 questions:

    1. Chances of intelligent and technology-oriented life developing.
    Well, it’s happened at least once already …
    So I think it astronomically improbable that it wouldn’t happen a 2nd, 3rd …. time.

    2. How high is the universal technological ceiling (the highest possible technological level attainable)?
    – if it is very low = no interstellar travel
    – if it is moderately high = colonisation of entire galaxies will happen sooner or later
    – if it is very high = universe teeming with travelling aliens.

    I think we can rule out the extreme technology scenario, or we’d already be swamped by sight-seeing aliens, probes, interstellar immigrants and diplomats, etc…

    Live long and prosper,


  53. There are so many galaxy’s and stars with orbiting bodies that chances are that there HAS to be life out there. Are they more or less advanced than ourselves…. well that is anyones guess. It would only be logical to assume that they are very near to our own technology, with only ourselves as an example of how long it takes to develop rudimentary space travel and technology. Of course what impact did a meteor wiping out the dino’s have to our development? Would we even be here if the meteor didn’t impact Earth? Someday we will break the speed of light just like we broke the speed of sound. It is funny that we forget so easily how we used to claim the speed of sound was the upper speed limit.

  54. I hope that you are correct about us being able to go faster than the speed of light- It would be quite handy to have for space travel. However- the known laws of physics strongly suggest that nothing in our universe can go faster than the speed of light and we have not observed anything breaking this rule.

  55. Back to the basics of the original study. If we want to make our presence known (not discussing why) then sending radio signals as a first step is nonsense.

    If you are on a deserted island and see a boat on the horizon you do not start by writing on wood panels – you make some fire to catch the attention of the sailors on the boat, ie. you draw attention to your location *before* attempting to send a message.

    So how can we make our solar system special – as seen from far away – so that “aliens” can take notice and look more closely at all planets here until they find us and our radio messages ?

    One previously mentioned project is to build a large triangular sail and put it in close orbit around the sun. It has to be large (5000+ km) so that the solar light is dimmed enough as seen from remote stars. And why a triangle ? Obviously because it is the simplest geometric form that *never* exists in nature – hence draws attention.

    Building this type of orbiting solar sail is probably not yet possible today but could be in one or two decades.

    Food for stuff. And BTW it would be interesting to search for orbiting triangles around remote stars now..


  56. What if live on other planets would be so intelligence that what ecer we do or create is already been created by them and what if they purposely wana let us know something because no human intelligence have ever landed on planets like mars or jupiteror mercury…..What if………because cameras pics can be changed and telescopes havent been created till that far….Question of rolerof tech

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