Rethinking Alien Encounter

by Paul Gilster on October 6, 2010

by Larry Klaes

Larry Klaes wraps up his two-part essay on our attitudes towards extraterrestrials by looking at how the subject has been treated in the past, and speculating on the scenarios that might bring disaster. Do Earth-shattering depictions of space invasion reflect what people really believe, or are they merely a form of escapism? Either way, they tell us something about ourselves as we confront the possibility of contact.

For those who may still wonder and question just how much weight the words of the famous cosmologist Stephen Hawking hold for the concept of alien intelligences and their potential reactions to encountering humanity, consider this: A new science fiction film coming out this November titled Skyline has recently premiered its theatrical trailer, which you can view here. The trailer begins with the line: “On August 28th, 2009, NASA sent a message into space farther than we ever thought possible… in an effort to reach extraterrestrial life.”

Now it is true that a transmission was sent from Earth into deep space on that very date and it was indeed broadcast by a NASA-owned radio telescope located in Australia. However, the collection of messages sent into the Milky Way galaxy from people all over the world as part of the Hello from Earth campaign were aimed at a planet in the red dwarf star system of Gliese 581, which is only 20.3 light years, or 194 trillion kilometers from us. Now that may seem like a long way to Earth-bound humanity, but on a celestial scale the Gliese 581 system is a near neighbor. Besides, the transmission, moving at the speed of light (almost 300,000 kilometers every second), is just over one light year from Earth as of this writing. That isn’t even far enough to reach our closest stellar neighbors, the Alpha Centauri system at 4.3 light years distant, let alone be properly given the title of the farthest human message ever.

As a final point, we are far from certain if any life of any kind exists either on or near the target of Hello from Earth, the fourth world circling the star Gliese 581. However, astronomers now think at least one and possibly three planets in that system have the potential to possess water in a liquid state, a major ingredient for the formation of at least terrestrial types of life. Of course the transmission is not going to stop once it reaches that alien planet. The messages will spread outward and onward into the galaxy at light speed, which will give them an increased chance of being detected some day by an ETI, assuming any exist in the signal path.

Image: Alien devastation in the upcoming movie Skyline. Credit: Universal Pictures.

With this inauspicious beginning to the trailer, the viewer is then treated to some apparently real news broadcasts about Hawking’s alien warnings interspersed with images of strange bluish-white meteor-like lights dropping down upon the city of Los Angeles. In the news segments, former CBS Television news anchor Dan Rather intones that “if extraterrestrials visit us, the outcome might be similar to when Columbus landed in America. In other words, it didn’t turn out too well for Native Americans.” The trailer caps off this dire warning with the text “Maybe we should have listened.” And done what, I have to ask? Cover Earth in black tarp with some stars painted on the outside and hope nobody notices us?

Too late, the alien Columbuses arrive in their bizarre and menacing spaceships over the city, looking like some kind of gothic metal sculptures bearing down on the places where the lights had landed. A quick reveal is made to the audience of the name of this film being advertised and then the final scene: A close-up of one of the alien vessels hovering over LA, its underside open wide like the jaws of some immense beast, pulling thousands of tiny screaming, tumbling humans up through the air and into itself for reasons as yet unknown, but ones the audience has little trouble imagining may not be for the benefit of humanity.

A final text warning suggests that we “Don’t look up”, which is directly counter to what our society has been taught in terms of social progress and evolutionary development – to say nothing of what the recently deceased astronomy popularizer Jack Horkheimer said at the end of every episode of his PBS program Star Gazer, which was to “Keep Looking Up!”

More Than One Side to the Alien Encounter Debate

Aside from the more than likely possibility that Skyline will be little different or better than the majority of alien invasion stories of the last one hundred years, using the real words of a real scientist (and a cosmologist at that) to give a sense of weight and urgency to just one side of the concept of alien interaction with our species and our world ultimately blurs and overshadows the wider range of possible behaviors and outcomes for what may one day define the ultimate course of humanity among the stars.

While it is true that the primary overall purpose of Skyline is a material one – to line the pockets of its makers with money by appealing to the basic instincts of those who will provide said profits – the film (and Hawking) are nevertheless contributing to the debate on whether and how we should deal with other intelligences in the Cosmos. This is the case whether the filmmakers had any deep intentions of doing so or whether the idea is plausible or not.

Since so many science fiction stories about aliens tend to focus on the negative aspects of and possibilities for encounters between varied species, thus biasing (and reflecting) public thought on this topic, it is both fitting and important to take a look at just how plausible Hawking’s dire prediction and all the related ones truly are. There are of course certain limits as to how much one can reasonably determine what an ETI may or may not do in regards to humanity in its present state: Not yet knowing for certain scientifically if there is any life beyond Earth tops the list here. However, we do possess enough scientific and technological knowledge to make some plausible determinations on just how likely our greatest fears about our galactic neighbors might be true or not.

Image: Skyline‘s imagery portrays alien encounter as disaster. Credit: Universal Pictures.

Just as there has to be a set of solid parameters for current SETI on this planet to work, meaning that a society has to have both the means and a purpose which presumably is not willingly detrimental to itself to signal others across space and time, so too must there be some sense of foundation regarding an alien invasion or attack.

As SETI requires its hypothetical subjects to share some common elements with humanity in order to work, any beings who wish to do harm on us must also think and behave with some similarity to us. So when examining the types of invading alien beings, I am excluding the ones with abilities we would consider to be godlike: Able to appear at will anywhere or anytime and commanding so much knowledge and power as to make the act of rendering us extinct a quick and easy exercise. I make the presumption that if such superbeings wanted us gone, it would have been done by now. The fact that it has not happened could mean a number of things, such as they are much too smart and nice to harm lesser life forms, or they don’t care about us one way or the other, or they will destroy us but they just haven’t gotten around to it yet. As a result, I am staying away from speculating any more on the superETI, except to warn that beings which are given abilities to do just about anything blur the line between physics and supernatural magic. In addition, I make no pretense that my lists of alien motives and weaponry are in any way complete, so further ideas are welcome.

The Why of Alien Invaders

Assuming that invading another world across interstellar distances requires some serious time, currency, and resources, our hypothetical alien marauders will not be attempting to take down humanity and its home planet on a whim or to follow some cliché of galactic hegemony. Like the future humans in the 2009 film Avatar who travelled 42 trillion kilometers to reach the Alpha Centauri system moon Pandora for its mineral wealth to aid their ailing civilization, our invaders will have to come up with a very good reason for traveling all that way if they ever literally want to leave the ground.

Of all the “whys” for an alien assault on Earth, taking our planet as a new place to live and utilize because their homeworld is dying or destroyed for one reason or another, is at least as old as H. G. Wells’ The War of the Worlds.

Well’s 1898 novel was a combined reflection on how European colonizers of the era were treating the people and places they were colonizing and an extrapolation of the idea of advanced beings responding to the slow but inevitable demise of the habitability of their home planet, in this case the fourth world from Sol, Mars. The numerous astronomical reports of seemingly straight lines on the Red Planet since 1877 had led to speculation that they were artificial in nature.

One fellow, the wealthy American astronomer Percival Lowell, championed the idea that the lines were actually immense canals built by the Martians to bring water from the icy white polar caps to quench their drying and dying cities. While Lowell seems to have assumed the superior Martians would eventually accept the end of their species and become extinct with dignity, Wells imagined these same creatures not wanting to go down with their planetary ship, thus their invasion of Earth.

Image: This early issue of Hugo Gernsback’s Amazing Stories brought H.G. Wells’ War of the Worlds to a new audience.

Now of course one advantage Wells’ Martians had over just about any other species in the Milky Way galaxy was living so relatively near to our world. A conventional rocket can propel a spacecraft to Mars in a matter of months, as they have in reality since the early 1960s. However, it is an entirely different matter to send a ship between even the nearest stars. Unlike the vessels of science fiction which are equipped with fanciful warp and hyper drives or have a conveniently placed cosmic wormhole nearby, our current knowledge of what it would take to get from one star system to another is fraught with technological and celestial hurdles that make even a slow multigenerational ship a daunting task.

So even if say an alien planet was going ecologically, geologically, or cosmically south, would it be wise to say nothing of practical to send a fleet across interstellar space to take over another star system, when unless their sun was turning into a red giant or going supernova, it would be much easier to utilize the worlds in their own solar system for resources and settling. If, for example, an alien society was in desperate need of water like the Martians of Lowell (and presumably Wells), it would be much cheaper by comparison to mine the many, many comets that we know exist around other stars, just as they do at the fringes of our Sol system. And while we have yet to detect any exomoons, we do know that most of the moons circling the four Jovian planets are covered in water ice and in some case, like Jupiter’s Europa, likely have deep global oceans of liquid H2O.

The same goes for mineral resources. There are estimated to be many billions of whole solar systems in the Milky Way galaxy alone. Presumably they have lots of planetoids in addition to their major worlds and the comets, just like our celestial neighborhood. It is also probable that many of those worlds are uninhabited but rich in elements that a technological civilization would find useful. So even if our marauding aliens do want to journey all the way across the galaxy for gold or oil or whatever, with so many star systems to choose from, why focus on Earth and its environs when the pickings are so easy and plentiful elsewhere? Plus since hauling all those rocks home would be expensive as all get out, trying to colonize a solar system that already has one intelligent species, even if that species is just starting to explore and utilize space, might be more trouble than it is worth.

Now let’s look at another classic reason for an ETI to want to come to Earth: Dinner. It has become practically an old joke that some aliens would see all the teeming life forms covering our planet and consider us an open buffet. Not only do we once again invoke the question of whether it would be worth going to all that time and expense for a meal when there are probably much closer snacks at home, but it has been said that our biochemistries would be so different that Earth organisms would be pure poison to an alien creature (and vice versa). The vastly different genetics would also go for interspecies breeding, especially since it is considered unlikely that we and they will look anything alike. As for needing a race of slaves – robots would be so very much less expensive and far more efficient. This all sounds like some very old and very low-grade science fiction in any event.

Image: This classic episode of Twilight Zone featured Damon Knight’s short story ‘To Serve Man,’ in which the idea of humans as menu items made a sardonic appearance. Credit: Cayuga Productions/CBS.

If it is just too much to fly all the way here for rocks or a meal, are there any other reasons why an ETI might still want to exterminate us? We may not be a threat *now*, but perhaps some day if we do spread ourselves into the galaxy, there might be others who could see us as future cosmic competitors for all the places and resources previously mentioned. If the galaxy has beings who think and act in very long terms, certainly much longer than most present humans do, they may not want to wait until our descendants are arriving at their doorsteps and instead take us out now.

I for one would like to think and hope that a stellar island of 400 billion suns over 100,000 light years across with perhaps 100 billion galaxies beyond our Milky Way in a Universe 13.7 billion light years wide would be plenty for everyone. However, perhaps some cosmic real estate is more choice than others and its finite nature makes it a valuable target worth fighting for. One estimate I saw in a Scientific American article from 2000 said the galaxy could be conceivably colonized in just 3 million years – a very short time compared to the 10 billion year age of the Milky Way. The fact that our planet appears to be free of any alien conquerors/settlers may say something about that idea, or perhaps conquest and colonization is not as popular as we might imagine (and often do).

Even if we and others decide to be planetary homebodies for many generations, there will come a day when a home system’s main source of light and heat, their sun, will begin to die out. Our yellow dwarf star is no exception: Sol is expected to start making things pretty unbearable on Earth in just a few billion years as our sun begins to expand into a red giant star. Even if Earth is spared being swallowed up by this bloated monstrosity of hot gasses, our planet will be cooked into molten slag, killing anything living that remains. Earth will later turn into a frozen iceball as Sol shrinks into a white dwarf and eventually a dead, dark cinder of itself. Even if our planet survives all this in at least its physical presence, when Sol goes completely so will Earth, its icy battered carcass floating off into the depths of the Milky Way as a rogue world.

So while we do have several billion years to prepare for this event, the point is that eventually nature will force our hand and make us choose either flight or extinction. Even staying in distant parts of our system will pass once Sol starts collapsing upon itself. And this is the fate of every star some day, even the very long lived red dwarfs, though some suns will also turn supernova or collapse into neutron stars or black holes. I know things will be very different in those distant epochs, but doing more than briefly visiting Earth or anyplace else nearby in those eras seems infeasible at best and deadly at their worst.

Have other species around other suns realized this about their celestial hearths as well? Will they decide to stay at home and wait for the end, or will they pack up and look for worlds where their suns won’t be going out quite so soon? Will the fact that we have at least a few billion more years of relative safety be appealing to such refugees? What happens when it is our species turn some day? Perhaps there are many vague and hidden factors which will render all this particular speculation and prediction moot, but at least this idea has the merit of being a plausible reason why one might have to go interstellar voyaging.

Image: From the film Alien Invasion, strange craft fill the skies over Earth’s cities. Credit: Richmanclub Studios.

Another reason ETI might want to come to Earth is a religious one. Perhaps like certain segments of humanity there are alien beings who have very strong spiritual and religious beliefs and it is their sacred duty to share the Good News with everyone else, whether they want it or not. Will alien missionaries ply the stars seeking to convert other species to what they perceive as The Truth, perhaps affecting their “heathens” in the same way that missionaries affected the cultures of the Pacific in their zeal to save souls – settling in some very nice real estate in the process. What will happen when a human group and an alien collective of very intense and very certain religious missionaries encounter each other? Or is religion a primarily human concept? Well, so far we have not been forced to worship any strange alien deities by clergy from the stars. Unless some of our current religions were the direct result of an ancient missionary visit.

How Might They Vanquish Us?

Although we have now looked at the primary and most obvious motives (to us at least) for an alien species to want to crush humanity and found most of the feared concepts wanting, it is time to explore the ways that said alien marauders might still take us out of the galactic picture. Ironically, while the potential motives for invasion and destruction are often weak if not outright impractical or implausible, the methods that a smart but aggressive species might want us gone (or we they) are often even more likely and effective than the usual imagined scenarios for the conquest of Earth.

If asked to visualize how an alien race might come after humanity, the scenario that seems to jump to most people’s minds is the one of giant spaceships hovering over major cities (Skyline is just the latest incarnation of that scenario), or a whole fleet of shiny silver spinning disks carrying troops of alien soldiers wearing shiny silver spacesuits and gripping laser rifles in their clawlike hands.

Now while one cannot entirely rule out the possibility that one day Earth’s skies will be filled with large and dangerous alien vessels up to no good for us, the idea that more advanced beings would engage in a battle for Earth and against humanity in a manner similar to the scenarios described above seems about as efficient as targeting our world for its supply of water with all the much easier and more effective alternatives available.

If you want to get rid of the higher life forms on Earth and don’t care if most of the flora and fauna inhabiting our globe also gets destroyed in the process just so long as the planet remains intact, then all you need to do is attach some rocket motors to a collection of planetoids and manipulate them so their ultimate destination is Earth. Humanity could be doing this with some of the smaller varieties of space rocks in just a few decades if we choose to, so a species that has actually made it to our Sol system via starship would be able to conduct this activity too.

Depending on the size and mass of the planetoid and where the ETI would target it, our civilization if not our very species could be rendered helpless in short order in a style reminiscent of the dinosaurs 65 million years ago. Indeed, there have been a number of small planetoids which have come close to Earth in recent times that astronomers discovered just a few days before their close encounters, leaving very little to no time at all to develop any countermeasures had they been on an intercept course. And these objects were guided only by the forces of nature! A deliberate use of planetoids to smash us into submission or worse is a scenario that has been discussed and written about, but a real organized defense system is still decades away.

An even more frightening concept is using a starship itself as a weapon. A large enough vehicle moving at relativistic speeds, even a fraction of light speed, could hit Earth with more force than humanity’s entire nuclear arsenal at its peak in 1990 (55,000 nuclear bombs). Such a weapon would be very hard to track and virtually impossible to stop at our present state of things.

Image: Artist’s impression of an asteroid strike. Do we have any defense against this kind of impact? Credit: NASA.

The details on this scenario, along with a very interesting discussion as to why an ETI might do such a thing to us and others (take out any potential aggressors/competition before it does the same thing, in essence) may be found on this part of the Aliens chapter of Atomic Rockets from Winchell Chung’s fascinating Web site.

Keep in mind that while Chung does make some very compelling arguments, he is also a very big space war gamer, so having a galaxy full of mature, peaceful, and altruistic beings may make for a nice place to live on a cosmic scale, but a rather dull RPG. Going on the offensive with other species is also a pretty good guarantee that even an advanced ETI that gave up aggression and war ages ago may not like being threatened or seeing others in such a state and take action against such a paranoid and self-serving race.

Another method for taking us out is one that has probably happened naturally across the Universe since the first stars came along: Supernovae. An exploding star would not only vaporize the members of its system but spread deadly radiation for hundreds of light years around. Earth has obviously survived having its native life forms become completely extinct by any stellar explosions over the last four billion years (and we can thank a supernova for even being here in the first place, as astronomers say it was the violent death of an ancient star some five billion years ago that kick-started the cloud of dust and gas that became our Sol system, along with giving us the elements needed to make life possible), but if an advanced species knew how to make and control a stellar detonation, they could fry us and our galactic neighborhood. Other methods of sterilizing whole solar systems includes smacking two black holes together and directing galactic jets, which are streams of particles and radiation thrown out by massive black holes in the cores of some galaxies. One hopes it won’t be possible to harness such energies, but who knows what beings that can survive and grow for eons in this Universe might be capable of.

Another cosmic weapon which fascinates and frightens is known as the Nicoll-Dyson Beam. Dyson Shells are a fascinating concept in their own right: Freeman Dyson envisioned a society taking apart its solar system and building a vast swarm of communities around its sun to collect as much energy from it as possible (right now 99% of Sol’s energy gets “wasted” into space). From a distant vantage point, anyone monitoring such a system would see its star gradually dim in the optical realm and brighten in the infrared region of the electromagnetic spectrum.

Being able to collect and utilize so much energy from a sun has many benefits for an advanced technological society – and a few dangers for others as James Nicoll would later point out. Dyson Shells would be able to focus and redirect the solar energy they collect into tight and powerful beams called a phased array laser. The beams could easily destroy whole worlds many light years from the Dyson Shell.

Whether Dyson Shells actually exist and would their makers use them as galactic-scale weapons is another matter (though there have been actual SETI programs which attempted to find these astroengineering projects), but this page from the Orion’s Arm Web site gives an interesting visual and text description of this idea.

Is SETI Itself Dangerous?

There have been many who warn about sending greetings and other messages into the galaxy and beyond. The idea, called METI for Messaging Extraterrestrial Intelligences, is that since it may be hard for an alien species to find Earth and humanity among the 400 billion star systems of the Milky Way, we should increase the chances for detection by broadcasting into deep space towards what we think are favorable cosmic places for intelligent life. The main idea behind SETI is that alien beings are conducting their own METI programs, as that is likely the best and easiest way for humanity to detect another society in the galaxy at present.

The main and obvious issue with METI is that we do not know what other kinds of beings are out there. Folks such as Carl Sagan have speculated that aggressive species tend to wipe themselves out before they can achieve space travel. However, this has the flavor of painting an alien race with the traits and behaviors of our species. What if there were species which cooperated as a unit and still decided that other beings must go before they become a threat to them? Or what if they felt that other species, being viewed as inferior, were in need of a serious “makeover” that would effectively destroy whatever made the target species unique?

Some have speculated that an ETI might take out humanity and any other species at our stage of knowledge and development by operating a METI program that carried what we might call an artificial virus. The target species would pick up the alien “message” and in the process of decoding it would unleash a program that could do all sorts of dangerous and deadly things, from taking down our technology to giving us the plans for a superbomb that would detonate once we built it from the instructions given in the message. Other potential scenarios involve converting humans into their puppet slaves or replicating the alien species on Earth to take over and then aim more such messages at other potential worlds to continue their galactic conquest.

Of course it would seem easy to make sure that this never happens by simply keeping the alien message isolated or just never building the design plans. However, the combined excitement of detecting an ETI signal and the often wild, vast, and intricate nature of the Internet could bring about the spreading of the virulent message and be released by those who feel it is their right to have and know such information. In addition, as we see in the news on a regular basis, there are those groups of humans who might deliberately want to open up this cosmic Pandora’s Box to spread death and destruction across our planet for their own purposes.

Image: As iconic as it gets, this still from Independence Day highlights the menace from above. Credit: Twentieth Century Fox Film Corporation.

This Web site goes into detail about the possibilities for an alien species to take out Earth without ever having to leave home either in person or even through a robot vessel.

Final Thoughts

This essay began thanks to Stephen Hawking’s well-publicized views on alien intelligences which he thought would not be a good thing for us to encounter any time soon. While there is of course the possibility that we might encounter an alien species that is a threat, I was unsatisfied and disappointed with Hawking’s version of this scenario. It struck me as not only being one-sided, limited, and old fashioned in thinking, but far too reminiscent of numerous recent Hollywood-style science fiction plots – an industry not exactly known for its rigorous scientific accuracy.

Hawking’s take on alien life feeds into this negative, paranoid, and inward-looking attitude regarding the unknown that seems to be growing in human society these days. While it is prudent that we do not just jump into the galaxy without at least having some idea who and what is out there, focusing on the idea that all alien beings are hostile monsters and that we should dismantle our radio telescopes and hide under our beds is not exactly the actions of a healthy, maturing society. Besides, if an ETI were out to get us, remaining ignorant of the Universe and trying to be undetectable is not the way to go.

As I have pointed out in this essay, an advanced alien species will be able to destroy us in short order and we will have little recourse to stop them at present. The fact that it has not happened may mean they simply haven’t found us yet, but it may also mean that we are either lacking in large numbers of intelligent galactic neighbors or that taking out another species that has barely gotten its feet wet in the cosmic ocean is not the way to behave as a galactic society. We still have far more to worry about from members of our own species bringing down civilization than any hypothetical alien species anyway.

Another thing I do know about human nature: No matter how many warnings and precautions and even laws that get thrown up to control people when it comes to what society thinks is in its best interests, there will always be individuals and groups of people who defy these rules either because they disagree with them or because it is in their nature to go against the grain.

This will apply to voyaging into space as much as anything else. The only reason it hasn’t happened already is due to the technological difficulties in making a deep space mission a reality at present. However, I know once we establish a serious foothold in space in our Sol system, there will be groups who will not want to remain confined to our celestial neighborhood but want to venture to those countless stars surrounding us. This will keep happening for as long as humanity lasts.

This is the eventuality we must prepare for, because I will agree with Hawking on one thing: If life’s evolution is similar everywhere, then it is likely that some other species will also share our drive and desire to see what it out there beyond their home world. It may be only a matter of time before we are visited. How we respond to them depends not only on their intentions but how much we have learned and evolved when it comes to understanding the Universe as well. Hopefully we will not let our fears and hostility turn a potential friend into an enemy.


jonathan October 8, 2010 at 15:21

One more fun idea to consider. We know that it may be possible to create quantum communications systems, which would allow instantaneous or near-instaneous data transmission, even when separated by vast distances.

You could have an alien race send mechanical armies to do their fighting for them, well ahead of the aliens landing/colonization party. Equipped with quantum communications, the robot/mechanized army could do the alien’s dirty work for them, controlled in “real-time”. Rinse and repeat as needed. Once the resistance has been destroyed, send in the colonization teams.

Here’s the thing, if Human beings are capable of being completely sociopathic, who kill for fun, who’s to say that aliens couldn’t be capable of the same? There’s no reason to assume altruism from aliens as a default position.

Procyan October 8, 2010 at 19:57

They’ll look like Danny Thomas and take away our imaginations and our thumbs.

Duncan Ivry October 8, 2010 at 21:41

Larry Klaes: “Wait, wait – on what do you base the idea of Dyson Shells as weapons being “ridiculous”? And as for using planetoids to bomb Earth, I was talking about an ETI starship in our Sol system conducting this, not from across the galaxy.”, etc. etc.

Please, Larry, don’t take the following wrong — I appreciate your work very much — but you make one big mistake: Stating, that certain fantastic projects are possible, and — if somebody else doesn’t accept it — loading the burden of prove onto the opponent.

Dyson shells as weapons, asteroid bombs, ETI starship in our Sol system conducting whatever, … it is still merely your unfounded opinion, that the feasibility has been proved. There still is a vast amount of unfulfilled preconditions for each of these very advanced projects, espescially in the areas of theoretical and experimental physics, and material sciences. Because of this, we simply do not know, whether any civilization — alien or not — will ever be able to realize something. And all this is questionable, because unfulfilled preconditions imply what? Nothing.

Tarmen October 9, 2010 at 12:06

We may be just psychologically blocking ourselves from the possibility of ‘animals’ smarter and more aggressive than us, the champions of the Earth. Smarter than us!!??? Impossible!! For many years, mankind has has been top dog. But there were epochs of our history when we were easily chased off by other animals. During the Ice-Age, large predators preyed upon human children and the weak or isolated. We weren’t always ‘top dogs’ , even on this one planet.

We might be in for a shock if smarter ‘others’ find our happy valley. We should certainly not intentionally try to attract attention from the unknown. Keep a low profile. We are not strong enough yet. We need another several centuries to build up our young technology.

Montie October 9, 2010 at 12:28

If there was ever one good reason that another society might wish to destroy us it would be one of paranoia about paranoia. Imagine Hitler winning and ruling the world and turning his mind to possibilities of aliens.

If you really wanted to end another world you don’t have to go there, capture as much of that free solar energy as you can and point a laser towards your target to heat things up a bit(or alot).

Of course, this could possibly be seen by others who then might become a bit worried about you. Interstellar deterrant laser wars anyone?

Eniac October 10, 2010 at 22:50

@amphiox: The scenario of lying low after arrival to build up an industrial capability is a good one. It would allow the invaders to avoid all the situational disadvantages as new arrivals, and bring their technological superiority to bear, fully. We would need to destroy them before they can settle, which they could make impossible by settling in the far outer reaches of the system.

I think it is much easier to spot the deceleration than you think. It consists of the full force of star drive exhaust directed towards us, and it lasts for years. Plenty of time to discover it and make very careful measurements. It may even become dangerous as the ship closes in.

The only way you can get the replicator you speak of (essentially an industrial manufacturing seed) to be as small as you say (a few kilograms) would be with nanotechnology. Possible, but that would make the speculation much less fun, since we have pretty much no idea what such technology would look like and how it would be used. Without nanotechnology, a replicator able to set up a full industrial capacity from scratch is normally estimated to be hundreds of tons in weight (Freitas has written a lot about this).

Another thing to consider is that it is very unlikely that there will be actual aliens on that expedition, which pretty much makes it a standard von Neuman probe scenario with bad intentions, aka Berserker. If we assume that AI’s promise will never be fulfilled (as at least some here think), we may just be able to outsmart them, since they are too far away from their actually intelligent masters to get any useful help. If AI does work out, things may be too strange to speculate about, again.

Lastly, consider that any race that has conquered the stars will probably not be dependent on their home planet, if they even still use it. Which means they are not vulnerable to extinction and would not need to be too paranoid about up and coming rivals. They could at least wait until we send the first of our own starships out.

kurt9 October 11, 2010 at 19:08

How about an alien ecological infestation, like how its depicted in “The War Against the Chtorr”? Instead of Terra-forming, we get Chtorra-forming.

ljk October 13, 2010 at 23:29

Take this for what it is worth: A detailed description of how to disassemble a solar system to make a Dyson Shell (or Matrioshka Brain – more or less the same thing):

Where a galaxy-spanning species might really want to go for resources:

ljk October 13, 2010 at 23:35

This thought I want to add: Since humans started thinking about alien life going back to the ancient Greeks over two thousand years ago (and by alien life I mean mortal beings in this Universe, not spirits or gods from some supernatural realm), it has only been in the last few centuries that people began to view ETI as potential threats to our species and planet.

Before then the Universe beyond Earth was pristine and perfect, unlike our corrupt world. Few even considered any intelligent neighbors to be any kind of a real threat.

I know our knowledge and awareness has certainly improved since those bygone days, but I just wanted to make this observation. We will see if we were better off being ignorant of the possibility of an alien threat or not.

Duncan Ivry October 14, 2010 at 15:35


Regarding “A detailed description of how to disassemble a solar system to make a Dyson Shell”.

For engineers these descriptions are far — really far — from a how-to. The author Robert Bradbury knows this obviously, because he tells “bad news” here and there about what we are not able to do. On the one hand.

On the other hand he uses bold expressions like “seems feasible in reasonable time scales” and “would be relatively simple”. And, as an example, characterizing planetary vaporization, cutting a planet into smaller planetesimals, and growing a planet’s surface — I’m inclined to ask: nothing else? — as “possible” solutions for something, is not very helpful for the case.

Well, that Robert Bradbury is no expert in big scale engineering or something like this, does not devaluate his endeavor — not at all. What he tells is inspiring. But realistically we should not put his publications into the neighborhood of detailed descriptions of how-tos. Robert Bradbury himself does not really claim this.

The situation is as I said before: a vast amount of unfulfilled preconditions.

ljk October 16, 2010 at 16:13

Perhaps instead of focusing on a solid Dyson Shell, which Freeman Dyson was not referring to originally as it is, perhaps that swarm of many colonies is more plausible. This could include a collection of hollowed out planetoids, some of which might later make for interstellar arks.

One reason why I think an advanced society would build Dyson Shells: Unless FTL travel or cosmic wormholes ever become reality, even races with superior technology will not be able to spread themselves very far in the galaxy unless they are willing to lose touch with those far-off colonies. Instead they will have to focus on their home turf and make the most of what is available, thus rearranging their system into something with lots of energy collecting area and room.

While not on the same scale, for a long while Optical SETI was not favored by the community because it was considered too difficult FOR HUMANS to send messages across the galaxy by laser or infrared beams. Let us not fall into that same trap just because building a Dyson Shell is beyond us at present.

Duncan Ivry October 16, 2010 at 20:00

@ ljk

Yes, I have already read about the non-solid Dyson shell. I think, if there will ever be built something distantly similar to a Dyson shell, it will be a construct with the shape and the function of a loose, deep, partial curtain — what you called a swarm –, but not a solid body. The most important reasons will be the statics of the construction, the amount of matter to handle, and the flexibility we would achieve. Because of too many false connotations, I would prefer not speaking of a “shell”.

Pure speculation ahead:
I could imagine, that in the very far future — if mankind prospers! — the same may happen to the solar system as currently happens to earth: Most humans live in cities covering vast areas, i.e. in space: vast volumes. And, yes, I mean: most humans *including* those on the surface of the earth. Parts of the constructs humans use may work like a curtain. Of course, there is an important difference: kind of “filling” the surface of the earth with humans and their constructs is relatively “easy” compared to doing the same with the volume of the planetary system. And before colonizing space, there are still the oceans.

ZIG October 19, 2010 at 11:26

Dyson shells are not needed (and yes, dispensable). High technology should mean “do more with less” and not “doing more with more.” Computers ancestors were huge and slow. Computers today are smaller and more powerful. The only reason to build a civilization of Dyson shells would be exhibitionism. First, advanced extraterrestrial civilizations really should seek sources of energy more discreet. Options?: Vacuum energy? Energy of gravity? Extraterrestrial civilizations evolved probably really can work very well with a single cell battery Rayovac.

ljk October 22, 2010 at 19:07

If you can build a Dyson Shell, you don’t have to worry about being discreet.

ljk November 15, 2010 at 2:09
ljk December 27, 2010 at 23:35

If an alien invasion really happened, we’d be dead instantly

In movies humans fight off alien occupation forces, explode alien ships, and mind-control aliens with the power of love. How on earth can we think that would happen?

Full article here:

DX January 1, 2011 at 5:20

What abour Rare Earth? Probable another alien civilization situated few billions or more ly from earth. They must search billion galaxies to find another planet with complex life form. Probable appeance of intillegence on earth was accident and there is not aliens in visible universe, only we. Humans was on edge of extintion several times, for example year -” The Sumatra volcano caused a 1,400-yr freeze which nearly drove us extinct, reducing population to under 10,000.”, ice ages and many other accidents.

ljk January 4, 2011 at 23:47

Wolves Among The Stars: Rethinking Who On Earth Controls Interstellar Policy

by Adam Frank

How naïve are we in our thinking about extraterrestrial intelligence and its inclinations? Here we sit, a newly high-tech species, unwittingly broadcasting our existence to anyone (anything?) with a radio receiver. Are we like baby birds chirping away announcing our presence to a galaxy full of predators? At what point do we reasses our assumptions, and our actions, and decide it would be wiser go radio quiet for the time being?

Full article here:

ljk February 14, 2011 at 2:16

6 Giant Blind Spots In Every Movie Alien’s Invasion StrategyBy S Peter Davis

Feb 12, 2011

Hollywood has fed us a steady stream of alien-invasion movies since the 1950s. At the moment we’re trying to forget Skyline and waiting for Battle: Los Angeles, which is coming next month. But this is a good time to ask ourselves why exactly the alien invasions we see on the silver screen always seem to end in disaster for the invaders, despite their ridiculously advanced technology.

With that in mind, we have some words of advice for any alien civilizations thinking of vaporizing us and stealing our brains.

Full article here:

ljk March 11, 2011 at 3:49

Why we love to fear E.T.

By Alan Boyle

Retired Air Force Capt. Robert Salas says he was at Malmstrom Air Force Base in Montana when UFOs hovered over the base in 1967 and nuclear missile launch systems somehow went non-operational. So you might think that watching the latest alien-attack movie, “Battle: Los Angeles,” would cause him some sleepless nights.

Not really.

Salas doesn’t think the aliens are in any mood to launch a globe-shattering strike like the one in the movie. “If they were going to attack, they would have done it by now,” said Salas, who serves as a consultant for the film project. “They could have caused a lot more destruction … but all they did was shut our missiles down.”

Full article here:

ljk March 19, 2011 at 12:55

I keep hoping Hollywood will make a good alien film. So last night I went to see Battle: Los Angeles with one of my teenage sons.

Well, besides the obvious fact that the filmmakers completely ignored my articles on why aliens probably would not land ships with troops to take down humanity, BLA will probably do for the USMC what Top Gun did for the US Navy; it felt like a multimillion dollar recriutment ad.

The ETI were of course humanoid in design along with the usual tentacles and slimy qualities. We never really got to know them except that their weapons were somehow fused to their bodies and they were very tough to kill. We did find out their motive for coming to Earth and I have absolutely no problem or guilt exposing this little plot point: They want our water. Yep, apparently in the entire Universe there is no other world with water of any kind.

As for the human characters, they are every by-the-book stereotype in these Michael Bay inspired flicks: The tough veteran sargeant with the heart of gold with a dark past who was just about to retire, the young virginal kid, the guys who are about to get married and have pregnant wives, and the cute little kids in danger. There was one female Marine and she was played by same actress who had pretty much the same role in Avatar. The dialogue and “inspiring” speechs could have been written by a computer.

And no surprise here: Our little band of lovable, tough Marines help to at least kick the aliens out of LA where the rest of the US military could not. And there probably will be a sequel. Trust me, I did not spoil anything for you because it is all so predictable.

Of course when I tried to tell my son these things right after the film, I was told I thought too much and I was spoiling the film and why didn’t I just enjoy it? Well, it was entertaining in a basic way, but there was nothing special about it. Even the first Transformers had an edge to it that made it stand out (that sequel was awful, though). Plus critiquing SF films IS my idea of fun!

And when my son asked me why I liked Independence Day even though it had a similar theme, I told him that it did not take itself too seriously plus the idea of giant colonies of starships roaming the galaxy looking for resources is a plausible one our descendants might actually do some day. Though why they had to get them from Earth and not the planetoids, comets, and moons was a drawback. Yes, I know, those places don’t have anyone to battle with.

Oh well, at least we’ve got Cowboys vs. Aliens this summer. That one actually looks like fun.

ljk April 8, 2011 at 10:53

Interstellar Predation Could Explain Fermi Paradox

If alien civilisations compete for scarce resources, the process of evolution may ensure that the survivors keep as quiet as possible

kfc 04/08/2011

In a casual chat over lunch back in 1950, the Italian-American physicist Enrico Fermi posed a now famous question. If intelligent life has evolved many times in our galaxy and beyond, why do we see no sign of it?

There are a number of standard reposts to this paradox. The first is that life is actually quite rare and humanity is the first species to become advanced enough to contemplate other civilisations.

Another argument is that intelligent species have been common throughout history but end up destroying themselves or their habitat with their own technology, such as with nuclear weapons or fossil fuel burning.

Yet another approach is that advanced civilisations are common and aware of us but keep themselves hidden for fear of disturbing our delicate culture.

Today, Adrian Kent at the Perimeter Institute in Waterloo, Canada, puts forward another possibility. His idea is that civilisations are common, that they have interacted many times in the past but end up competing for scarce resources. When that happens, the process of evolution, operating over vast time scales, ensures that the survivors learn to keep quiet.

That’s not an idea that can be easily dismissed. Kent says that one counter argument might be to point to the way evolution works on Earth. This usually operates on ecosystems in which species become interdependent in complex ways.

Although many species develop ways of camouflaging themselves, they do not end up hiding in isolation. So by this measure, Kent’s fears are unfounded.

But evolution on a cosmic scale would be very different, he says. Cosmic evolution must operate over vast distances and that the scarce resources offered by habitable plants would be very rare.

Kent puts it like this: “If cosmic habitats are widely enough separated that they are very hard to find, by far the best strategy for a typical species to avoid defeat in such competitions may be to avoid entering them, by being inconspicuous enough that no potential adversary identifies its habitat as valuable.”

That raises important questions about whether humanity is wise to advertise its existence. Various attempts to send messages to the stars have already been made and many scientists have pointed out that this could be a serious mistake, even a suicidal one.

Kent says the risk is easy to misconstrue. I’ll leave you with his conclusion:

“One can summarise the essential point simply enough. If there are no aliens out there, any efforts at communication were obviously wasted. Thus we can assume for the sake of discussion that there are aliens out there likely to receive the messages at some point.

“The relevant parameter, then, is not the probability of our messages being received by aliens who might potentially do us harm: it is the conditional probability of the aliens who receive the messages doing us harm, given that the messages are indeed received (and understood to be messages).

“Can we really say that this probability is so negligible, bearing in mind that any such aliens appear to have made no reciprocal attempts to advertise their existence?

“The arguments considered above suggest that we cannot.”

A sobering thought.

Ref: Too Damned Quiet

ljk April 28, 2011 at 8:18

Would contact with extraterrestrials benefit or harm humanity? A scenario analysis

Authors: Seth D. Baum, Jacob D. Haqq-Misra, Shawn D. Domagal-Goldman

(Submitted on 22 Apr 2011)

Abstract: While humanity has not yet observed any extraterrestrial intelligence (ETI), contact with ETI remains possible. Contact could occur through a broad range of scenarios could occur that have varying consequences for humanity. However, many discussions of this question assume that contact will follow a particular scenario that derives from the hopes and fears of the author.

In this paper, we analyze a broad range of contact scenarios in terms of whether contact with ETI would benefit or harm humanity. This type of broad analysis can help us prepare for actual contact with ETI even if the details of contact do not fully resemble any specific scenario.

Comments: 33 Pages, 1 Figure, PDF File

Subjects: Popular Physics (physics.pop-ph)

Journal reference: Acta Astronautica (2011) 68:2114-2129

DOI: 10.1016/j.actaastro.2010.10.012

Cite as: arXiv:1104.4462v1 [physics.pop-ph]

Submission history

From: Jacob Haqq-Misra [view email]

[v1] Fri, 22 Apr 2011 15:04:33 GMT (366kb)

ljk May 9, 2011 at 10:26

A nice tribute to Rod Serling and his classic television series The Twilight Zone along with the entire (but not final) script for the episode “To Serve Man”:

FYI: I always got a kick out of The Simpsons take on that famous episode in one of their first Halloween specials.

ljk May 21, 2011 at 3:11

The Myth of Evil Aliens

Why Stephen Hawking is wrong about the danger of extraterrestrial intelligences

By Michael Shermer | May 19, 2011 | 41

With the Allen Telescope Array run by the SETI Institute in northern California, the time is coming when we will encounter an extraterrestrial intelligence (ETI). Contact will probably come sooner rather than later because of Moore’s Law (proposed by Intel’s co-founder Gordon E. Moore), which posits a doubling of computing power every one to two years.

It turns out that this exponential growth curve applies to most technologies, including the search for ETI (SETI): according to astronomer and SETI founder Frank Drake, our searches today are 100 trillion times more powerful than 50 years ago, with no end to the improvements in sight. If E.T. is out there, we will make contact. What will happen when we do, and how should we respond?

Such questions, once the province of science fiction, are now being seriously considered in the oldest and one of the most prestigious scientific journals in the world—Philosophical Transactions of the Royal Society A—which devoted 17 scholarly articles to “The Detection of Extra-Terrestrial Life and the Consequences for Science and Society” in its February issue.

Full article here:

ljk June 21, 2011 at 0:46

When the skies fall: hostile aliens invade the small screen

The concept of alien invasions of Earth has reappeared on television recently in the form of a National Geographic special and a TNT drama. Andre Bormanis examines those shows and why the alien invasion theme may be in vogue today.

ljk July 29, 2011 at 0:59

Bad Aliens, Meme Armor, and Intelligence in the Universe

By Caleb A. Scharf | July 25, 2011 | 3


These are two posts from the Life, Unbounded archives. They were written in April and May 2010. Around that time there was a lot of media noise about aliens – brought on in part by Stephen Hawking?’s comments about fearsome “nomadic” lifeforms that might roam the universe. I’ve merged the posts here. As far as I know the idea about “meme armor” is an original one.

Debate about “intelligent” life in the universe is tricky. It’s long been colored by wild extrapolation, optimism, pessimism, and downright fantasy. But there is a need to think about it responsibly, because the question is real enough. The SETI program and SETI Institute have held out against many challenges to do just this. While I prefer an approach based directly on the blossoming science of exoplanets, it’s still fun to take the occasional dip into more speculative terrain.

Full article here:

ljk August 23, 2011 at 2:59

Setting the record straight on the recent “report” that ETI might destroy humanity because we’re not being nice to the trees and bunny rabbits:

Of course if an alien race were out to “punish” humanity for our anti-environmental ways, I would want to ask them how they were able to achieve a technological civilization and interstellar travel without digging up their worlds in the process, and why no other ETI apparently punished them for wrecking their ecosystems.

ljk December 23, 2011 at 14:22

Phil Plait, the Bad Astronomer, does his take on the whole alien invasion thing, naturally showing via science and various forms of logic why it will probably never happen and certainly not in the way Hollywood and most bad SF stories depict it:

He even throws in an article on why they cannot literally blow up the entire Earth or any other planet, either.

ljk March 13, 2012 at 22:33

‘Alien Encounters’: A few sage (and Sagan) thoughts on invasion

March 13, 2012 | 10:15 a.m.

When it comes to close encounters, Hollywood is pretty far off. That’s the take-away from ”Alien Encounters,” a pair of one-hour Science Channel specials that begin Tuesday night at 10 p.m.with ”Alien Encounters: The Message” and conclude with the March 20 premiere of “Alien Encounters: The Arrival.”

Writer and producer Nick Sagan and Jill Tarter of the SETI Institute are among the voices that delve into the discussion of how alien contact might take place and what the scientific, cultural and psychological effects might be for our planet inhabitants. Our Geoff Boucher interviewed Sagan (who is also the son of the famed astronomer Carl Sagan) about the traditional Hollywood spin on flying saucers.

GB: When you watch Hollywood’s portrayals of alien-contact films, what makes you groan?

NS: Humans having any kind of sporting chance against hostile alien invaders armed with superior technology. Good luck. If they’re advanced enough to cross the enormous distances of interstellar space, they’re advanced enough to wipe us out without breaking whatever in their physiology passes for a sweat. Why not just lob a few asteroids at us? How are we going to handle that? The conceit of plucky human underdogs triumphing at the end might make for feel-good popcorn movies but in reality there’s just no “there” there. Seriously, we beat them with a computer virus? Our microbes are their kryptonite? And why do they even want to attack us anyway? There’s no shortage of other planets they could enjoy, and if they really took a disliking to us, why not sit back and allow us to destroy ourselves? We’re certainly capable of it.

Full interview here:

ljk May 17, 2012 at 14:54

Here comes the latest Hollywood summer blockbuster flick about aliens invading Earth – and Seth Shostak of The SETI Institute tries to bring a little rationality and science to the proceedings:

To quote: This idea that maybe we shouldn’t broadcast our location, just in case — is this something that’s actively debated in the science community?

Shostak: I’m the chair of the International Academy of Astronautics, and we’re trying to re-write protocols of what to do, but it’s one of those very contentious things.

Some people think we shouldn’t broadcast because it would be too dangerous, but to me, that seems like kind of a funny thing to do because that means if you went out into your backyard, aimed a dish at Alpha Centauri, and sent them your poetry, that you’re somehow violating some international agreement and could be thrown in the clink. But the real reason why I think it’s not necessarily relevant is because we have been, and will be, broadcasting.

Any society that could come here could pick up the lights from New York. What should we do about that? Should we darken New York from now until the last human expires? Would we want to turn off all the radars at JFK airport? So if you could send a message out into the cosmos, what would you say?

Shostak: Well, if I was going to be able to get an answer back, I would say something different than a one-way message. If I was going to send a one-way message, I’d just send the Google servers. I would just send the entire Internet, because they would be able to figure out some of it. We’re able to decode languages from history when we have a lot of it, a big corpus of data.

But if it ever got to a point where you could get into a conversation and ask questions, my two have always been: do you have music and do you have religion?

I wouldn’t ask about physics because we could eventually figure that out, but those two questions are things only they would know.

ljk May 25, 2012 at 16:49

Aliens Don’t Want To Eat Us, Says Former SETI Director

by Jason Major on May 24, 2012

Alien life probably isn’t interested in having us for dinner, enslaving us or laying eggs in our bellies, according to a recent statement by former SETI director Jill Tarter.

(Of course, Hollywood would rather have us think otherwise.)

In a press release announcing the Institute’s science and sci-fi SETIcon event, taking place June 22 – 24 in Santa Clara, CA, Tarter — who was the inspiration for Jodie Foster’s character in the film “Contact” — disagreed with both filmmakers and Stephen Hawking over the portrayal of extraterrestrials as monsters hungry for human flesh.

“Often the aliens of science fiction say more about us than they do about themselves,” Tarter said. “While Sir Stephen Hawking warned that alien life might try to conquer or colonize Earth, I respectfully disagree. If aliens were able to visit Earth that would mean they would have technological capabilities sophisticated enough not to need slaves, food, or other planets. If aliens were to come here it would be simply to explore.

“Considering the age of the universe, we probably wouldn’t be their first extraterrestrial encounter, either. We should look at movies like ‘Men in Black III,’ ‘Prometheus’ and ‘Battleship’ as great entertainment and metaphors for our own fears, but we should not consider them harbingers of alien visitation.”

Tarter, 68, recently announced her stepping down as director of SETI in order to focus on funding for the Institute, which is currently running only on private donations. Funding SETI, according to Tarter, is investing in humanity’s future.

“Think about it. If we detect a signal, we could learn about their past (because of the time their signal took to reach us) and the possibility of our future. Successful detection means that, on average, technologies last for a long time. Understanding that it is possible to find solutions to our terrestrial problems and to become a very old civilization, because someone else has managed to do just that, is hugely important! Knowing that there can be a future may motivate us to achieve it.”

On the other hand, concern that searching the sky for signs of life — as well as sending out your own — could call down hungry alien monsters would make a good case for keeping quiet. And a quiet search may not get the necessary funding to keep going. I can see where Tarter is coming from.

Let’s just hope she’s right. (About the eating part, at least.)

Top image: Alien 3, © 20th Century Fox. Tip of the tinfoil hat to

ljk May 25, 2012 at 17:00

To quote from the above article I just posted here:

“On the other hand, concern that searching the sky for signs of life — as well as sending out your own — could call down hungry alien monsters would make a good case for keeping quiet. And a quiet search may not get the necessary funding to keep going. I can see where Tarter is coming from.”

How does passive searching attract mean aliens? Does the author mean METI and not SETI?

Sadly he does have a point about quiet searches for alien minds not getting the funding they deserve. The SKA that was just talked about in the news could do some very good radio SETI, if it is allowed.

ljk October 30, 2012 at 14:31

War of the Worlds

Live at the FitzGerald Theater

This hour of Radiolab: an examination of the power of mass media to create panic.

In our very first live hour, we take a deep dive into one of the most controversial moments in broadcasting history: Orson Welles’ 1938 radio play about Martians invading New Jersey.

“The War of the Worlds” is believed to have fooled over a million people when it originally aired, and it’s continued to fool people since–from Santiago, Chile to Buffalo, New York to a particularly disastrous evening in Quito, Ecuador.

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