Would Space Aliens Really Want Our Water?

I recently saw 2011’s “Battle Los Angeles” starring Aaron Eckhart and I thought it was a really good movie. I am sorry I didn’t take the time to watch it in the theater.

According to IMDB the movie did not make back its budget at the box office (you have to at least double a budget in box office sales to get close to breaking even, depending on how much marketing budget you spend). Maybe it’s doing better in DvD sales but I have heard nothing but ridicule and complaints around the movie.

I don’t understand why. All the military details are beyond my technical expertise but as a computer programmer who is constantly rolling his eyes at laughable computer technology in television and movies, I am sure that real US Marines and Air Force personnel could pick out errors in the film.

On the other hand, some people with scientific credentials have been wrangling with one of the silliest questions of all time: “If there are aliens out there, why haven’t they visited us?” This ridiculous question is informally known as the “Fermi Paradox” (although it’s not a paradox at all). There are so many possible (credible, plausible) answers to this question that there is even a book that refutes the idea (Cf. If the Universe Is Teeming with Aliens … WHERE IS EVERYBODY?: Fifty Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life).

There’s no science in our bin of human knowledge that says an intelligent civilization arising somewhere else in the universe would have to have found us by now — but neither is there any science in our experience that proves they haven’t already done so.

What does a space alien look like? Maybe they came and went. Maybe they pop in for a drive-by view every few days. For all we know, 1% of all UFO sightings are of real visits from space-faring civilizations; they are under no obligation to check in at the White House despite what some scientists will tell you.

All that aside, if we were to imagine ourselves as a star-faring civilization, under what scenarios would we want to invade and colonize another world already inhabited by one or more intelligent, sentient species? (Fact: Science has established that there are dozens of intelligent, social species sharing our planet with us — we’re the only ones so far to work with steel and concrete, in our experience.)

In the movie, one scientist suggests during a televised interview that the aliens must be interested in our water. That is the same reason why an alien machine invades Earth in the Tom Cruise movie “Oblivion”. However, I’m pretty sure that if they leave one star to travel to another, a seriously intelligent civilization would not have to launch a major invasion just to obtain water.

There is more water floating around the Solar System than can be found on Earth — and you don’t have to work with very much gravity to get to that water. I’m pretty sure that water is relatively common throughout our galaxy and probably the universe. So the idea that aliens would invade a planet (risking death to themselves and their species) for water seems preposterous to me.

A warlike species may simply want to kill all competitors. I can see that happening as we have had our own warlike cultures in the past. Warlike behavior is (in human experience) partly a cultural phenomenon and partly a process of the natural competition between life forms. Chimpanzees go to war, for example — but so do ants, bees, wasps, and termites (among other species). Warfare is not a uniquely human activity.

If an intelligent star-faring species is spreading across the galaxy, we have no real way to know what their expansion rate should be. A number of people have tried to estimate what it would take to cover the entire galaxy with a single species (really, a single ecosystem extended from a source planet). However, those estimates amount to little more than wild-eyed guesswork.

If you have an aggressive species spreading out into the galaxy, what is to say its culture won’t fragment and become hostile toward itself? What if we manage to carry our own wars to the stars? Gordon R. Dickson explored that very concept in his Dorsai books (which he formally called the Childe Cycle, a collection of stories and books he never finished). Jerry Pournelle also explored the idea of humanity exporting its political divisions and conflicts via his CoDominium/Empire of Man stories (a militaristic scifi universe he opened up to other writers).

Human emotion is a powerful motivating factor in our politics and our literature; although space aliens may not have emotions similar to our own, they most likely would have some sort of motivations to propel them toward survival and technological advancement. Those motivations might indeed lead to conflict.

But the galaxy doesn’t have to be so lonely. Instead of just two warlike species (us and the warmongering aliens who fight among themselves), there could be dozens, hundreds, even thousands of highly advanced, competitive species out there fighting for a dwindling number of habitable planets. That would be the Star Trek Scenario.

But such a highly competitive environment would inevitably lead to the development of alternative survival solutions. After all, not everyone will win out in the end. Some species might adapt to living in space rather than colonizing other worlds. It may be less expensive and more efficient to build custom habitats that simply orbit stars and leave the fighting to everyone else.

We occasionally toy with the idea of building space habitats in our entertainment and in our politics but we don’t yet have the technology to create a truly self-sustaining habitat.

But if building space habitats draws some species away from the fighting, why not get everyone involved in creating custom habitats? It would be simple enough to share the technology. In such a galaxy, peace would reign supreme and war would be an aberration. In which case, why go wandering off into the cosmos looking for trouble, except out of pure boredom?

Space tourism is a much more probable explanation for a lack of door-to-door alien mercenary attacks because it’s less risky and everyone gets to have fun. Your average space alien might be expected to keep his DNA to himself, to look but not touch as he visits rare planets that have spawned life. Every indigenous DNA pool might be treated with great dignity and respect — or perhaps great fear, as such the risks of exposing oneself to a foreign ecology’s DNA might be devastating.

I find it hard to believe that a sensible space alien tourist would want to come down to Earth and mutilate cattle; but it’s even less understandable that these violent aggressive species are probing our defenses by attacking herbivorous life forms. Sure, we are most vulnerable if we don’t protect our food supply but how would they know we’re eating these cattle? From space it might look like we’re just engaged in massive pest control.

Much as I enjoyed “Battle Los Angeles” (and I heartily recommend it to all science fiction and fantasy fans), I just don’t buy the “aliens came down here for our water” idea. Frankly, why attack all those coastal cities when they could just drop into the ocean and suck up as much water as they need?

“Cowboys vs. Aliens” had a more plausible explanation for alien visitations: they wanted our gold. Gold is fairly rare but I’m still not sure it’s worth traveling thousands of light-years just to suck up a small ship’s worth of gold. Besides which, couldn’t they extract more gold more easily from asteroids?

Maybe there are spectral signatures to stars and planets that reveal the existence of truly rare, universally vital resources. Such resources could indeed draw aggressive species toward us (eventually). They might be capable of anything, willing to do anything (such as dropping asteroids on a planet) to kill off a dominant species or ecosystem just so they can safely come down and harvest hard-to-find resources.

But would that call for an invasion with individual soldiers, fighter craft, and such? I just have a really hard time with that. In “Oblivion” the alien intelligence damaged our moon to cause severe environmental stress on Earth. Then it used clones of captured human astronauts to fight a war that nearly wiped out humanity. That’s more reasonable than an alien civilization sending an army across thousands of light-years (such as in “Battleship”) but it’s still not plausible to me.

An alien space-faring civilization that wants to harvest resources from a planet may be in constant starvation mode, so taking the time to fight for a planet (with a species that may have a secret weapon that tips the balance in its own favor) is a high-risk scenario. Unless these star-travelers are just a bunch of drunken warmongers who have found nothing more interesting to do with their time, I think direct warfare would be one of their last options to consider.

If an alien army lands on Earth they will have to be extremely desperate, perhaps very weak (by their own standards) for lack of some vital resource(s). In that scenario the invasion itself would be their Achilles Heel. And maybe that is why the movies have it right after all, because humanity usually wins out over the bad guys who came to take our stuff.

I just can’t see attacking another planet over its water. That water would have to have spiritual healing powers or something; otherwise, we can get to water much more easily than that.