SETI : Should we let Aliens find us?

Scientists are busy searching the stars for alien signals. They have even beamed a signal from earth hoping aliens might notice us. But is this a good idea?

The search for extra-terrestrial intelligence orSETI is an ambitious attempt by scientists to make contact with aliens by studying the heavens using radio telescopes. So far SETI has not met with any success, but that doesn't mean there are no aliens out there.

 

What many people don't realize is that SETI can only detect a very powerful signal that has been sent on purpose to announce the presence of the civlization. That's because to detect the signals of everyday life, like an ordinary analog TV transmission, you would need a huge radio dish that would be impractical and too expensive to justify. If there were a budding technological civilization even at the nearest star, transmitting simple radio signals using early 1900's technology, we might not be able to detect their presence. Finding a civilization like ours that was 50, 100, or 1,000 light years distant would be next to impossible.

So what scientists do is look for signals beamed into space on a particular frequency band that would be designed for detection. In the early days of the program, scientists not only focused on signals purposefly sent our way, but searched for radio signals in a band of frequencies related to energy transitions in the hydrogen atom. The idea was that aliens, having personalities exactly like astronomers on earth, would transmit a signal in this frequency band hoping to be discovered. In other words they would long for contact as we do, and use this frequency band to get noticed. For scientific reasons we won't get into here, if you wanted to be discovered by other civilizations you might in fact consider this because it would get you noticed by an advanced civilization that was studying astronomy using radio telescopes. There are technical reasons why astronomers, just studying stars and gases in interstellar space, will be looking at this band of frequencies. An artificially produced signal placed there would be easy to notice.

SETI is an admirable program. Scientists have to do something and are constrained by limited budgets for this kind of research. That's a shame really, I can't think of anything more important than finding out if there are other advanced life forms in the galaxy, but Congress thinks otherwise. They would rather spend money on healthcare and bombing places like Iraq, instead of giving scientists the resources they would need to fully explore this question. Right now SETI is surviving on private donations by forward-looking individuals like Paul Allen (founder of Microsoft with Bill Gates).

Now let's get to the bottom line of what SETI is looking for. This kind of search makes some big assumptions about what kind of aliens are out there. You're assuming that they're scientifically oriented, peaceful and benign, and social in the way mammals on earth are. None of these assumptions has any real validity, except for the scientific one. To attain enough technical skill to send a radio signal, aliens or extra-terrestrials will have to know science. But we can stop there.

We have no idea what the social structure or personalities or motivations of intelligent aliens will be. Now we know from the Drake equation that there are likely quite a few civilizations out there somewhere in the universe. I think its reasonable to assume their dispositions fall on a Bell curve type distribution. Some are going to be nice, some middle-of-the-road, and some outright hostile. They may or may not have any wish for contact with other civilizations. That's impossible to know.

In fact, they may want to destroy any civilizations they come in contact with.

If you remember the old Twilight Zone series, then you'll recall the episode where the benign aliens come from space to save earth from atomic destruction. They convince large numbers of earthlings to jump on board a ship to journey to the home planet. When its too late, the earth people discover that the aliens actually enjoy eating different species they come across in the galaxy.

While the Twilight Zone is a fantasy, such a scenario may not be all that far off from the truth. Many naïve scientists like to believe that getting more advanced means getting more peaceful. But has that happened on earth? Not at all. We're as violent as ever. Consider the time period from the birth of Christ to the year 2000. World War 2, which resulted in the deaths of about 60 million people, including some by nuclear weapons, occurred more or less in 1940. So about 97% of the time-span from Christ to the modern day had already passed. Were humans any more peaceful? No, humans were violent is ever, if not the most violent they had ever been. Being advanced scientifically doesn't correlate with peacefulness by any means.

Scientists might respond by saying, well you invent nuclear weapons, then you MUST get peaceful or destory yourselves. That may be, but what if peace is attained via a brutal dictatorship like the Nazi's? Suppose they had won World War 2, conquered all of earth and then embarked on a space program. What would their attitude have been running across slightly less intelligent life on say, Mars?

This is all fantasy and hypothetical, but the point is we cannot assume in any way that aliens will be benign. Being scientifically advanced doesn't make you any more ethical or moral. Let's go back to the idea that temperament falls on some sort of Bell curve. Really aggressive species may be outliers, but they might be the ones who are really successful. Knowing that science and technology approach and that earth could be near a so-called “singularity” after which computers develop without limit, they might be inclined to destory us so we don't infringe on their galactic empire. Some civilizations may even be evil, and like the aliens in the Twighlight Zone episode, they might actually enjoy enslavement or eating other aliens or who knows what.

Given that aliens sending signals out and engaging in interstellar space travel are likely to be far in advance of us scientifically and technologically, it may be wise for us to keep quiet. Its OK to study the universe in a passive sense for these type of signals. But we might think twice before announcing our presence to the universe and potentially alerting aggressive species that could destory a solar system in a blink of an eye that we are here.