Alien search won’t doom planet Earth, say scientists who want to contact ET

It’s interesting how these related stores seem to come in batches: Alien search won’t doom planet Earth, say scientists who want to contact ET | Science | The Guardian.

Fears that a major program to contact alien life could spell disaster for planet Earth were dismissed as “paranoid” on Thursday by scientists who hope to beam messages to distant worlds from powerful radio telescopes.

Researchers at the Search for Extraterrestrial Intelligence (Seti) Institute in California want to broadcast greetings to potentially habitable planets in the hope of receiving a reply, but the proposal has met with serious objections from critics, including the cosmologist Stephen Hawking, who claim that yelling into space is reckless.

…Under an active Seti program, messages would be encoded in powerful radio signals and sent repeatedly for hundreds of years to planets that lie in the habitable zones around stars. Seth Shostak, director of the Seti Institute, advocates beaming the entire contents of the internet, giving an intelligent recipient the opportunity to decipher the history of human culture, the rules of cricket, and countless hours of porn.

…Active Seti, as the approach is called, is not universally supported though. Hawking has warned that Earth’s own history provides ample evidence that an encounter with more advanced ETs could go badly for humans. By drawing attention to ourselves, he notes, Earthlings might suffer the same fate as befell Native Americans when Columbus landed in America. Others agree. Simon Conway Morris, an evolutionary paleobiologist at Cambridge, has urged governments to prepare for the worst because aliens might be as violent and greedy as humans – or worse.

I did a post yesterday talking about how much of a long shot SETI is.  Active SETI is an attempt by SETI scientists to increase their chances.  In my mind, the results of Active SETI fall into three possibilities:

  1. Civilizations are very rare and the nearest is millions of light years away, at least.  In this case, we’d be beaming out messages into the dark, and no one would be hearing them.  Unfortunately, for reasons I’ve written about before, I think this is the most likely scenario.
  2. Civilizations are pervasive, but interstellar travel is unfeasible.  (Which is why aliens aren’t here.)  In this case, neighboring civilizations may hear our signal, respond, and an exchange of ideas, across decades and centuries, could ensue.  Some of these exchanges might dramatically increase our knowledge and capabilities.  Both civilizations could be enriched.  This is the scenario SETI hopes for.
  3. Civilizations are pervasive, interstellar travel is feasible, but for some unknown reason, on one has visited us yet.

It’s in considering why 3 might be true, that people become concerned about Active SETI.  Would we be shouting out into the wilderness and making our presence known to hungry predators?  Could it be that the reason no one is broadcasting is because it’s dangerous?  Science fiction stories abound with scenarios like this, such as Fred Saberhagan’s berserkers or Alastair Reynold’s inhibitors: alien machinery that seeks out either life, or specifically intelligent life, and, for some reason, destroys it.

It’s worth noting that if interstellar travel is feasible, the Earth has been around for 4.5 billion years circling the galaxy, with unmistakable signs of life in the spectrum of light reflected off our planet.  If anything were interested in annihilating us, conquering us, eating us, or whatever, we’ve been an easy target for a very long time, for almost one third the life of the universe.  Even if all they want is raw resources, those are a lot easier to get in the Kuiper or asteroid belts without having to deal with gravity wells or pesky resisting natives.

The only scenario where we might be in danger is if there is something out there that just doesn’t like intelligent life.  While I can’t see a way to eliminate this possibility, it’s worth considering Shostak’s retort about this concern.

But the Seti scientists have now fought back. “It’s clearly too late to worry about provoking aliens with deliberate transmissions. Any alien society that is advanced enough to launch an attack and vaporise Swindon can easily pick up the broadcasts we’ve been sending into space since the second world war,” said Shostak,

He argues that a ban on sending signals into space would have to proscribe airport and military radar systems and even city lighting which can betray the existence of technology on Earth. “Such paranoid actions would cripple the activities of every succeeding generation of humanity,” he told the American Association for the Advancement of Science meeting in San Jose.

In other words, if there is a danger from broadcasting, we crossed that rubicon long ago.  There is already a sphere at least 70 light years in radius announcing our presence.

Of course, given that, you have to wonder how likely sending deliberate messages will be to provoke a response if all the voluminous content already broadcasted hasn’t.  (In the movie ‘Contact’, the aliens initially responded by broadcasting back the first thing they received from us, a speech by Adolf Hitler.)

So, my attitude toward Active SETI is that it’s still a longshot, but that it’s unlikely to put us in any danger we’re not already in, a danger I think is pretty unlikely anyway.

Unless I’m missing something?

Beasts or gods; why a War Of The Worlds is very unlikely

Image credit: Alvim Corrêa via Wikipedia
Image credit: Alvim Corrêa via Wikipedia

One of the scenarios that is often played out in science fiction is what would happen if we encountered an alien civilization.  Often, we are portrayed as defending Earth from an alien invasion or fighting battles with the aliens in a war.  Another scenario, commonly found in more culturally introspective fiction, focuses on what our responsibility would be if we encountered an alien society less advanced than ours.

These stories are a lot of fun, and they often give an opportunity for commentary on colonialism and other cultural issues in our society.  But the chances of either of these, or similar, scenarios actually happening is infinitesimal.  To understand why, let’s do a thought experiment.  Imagine three worlds, which we’ll call Planet A, Planet B, and Planet C.

Planet A is Earth.  It is about 4.5 billions years old.  Life began around 4 billion years ago.  Anatomically modern humans evolved around 200,000 years ago.  Planet A currently has a technological civilization which developed in the last few centuries.

Planet B is exactly the same as A, with the exact same history, except it is 1% younger (about 45 million years).  The dinosaurs have gone extinct on Planet B, primates have appeared, and there are a few other species with promising trends toward intelligence, but there is nothing on B that the inhabitants of Planet A would even remotely characterize as a civilization.

If the inhabitants of A decided to colonize B, the inhabitants of B would not even recognize the significance of A’s arrival.  To B inhabitants, A inhabitants would simply appear as a new type of animal.  Their equipment would also appear as new animals.  Their buildings and other structures would simply look like new kinds of rock or other parts of the landscape.  Not only would B not have any defenses against A, they wouldn’t even recognize that they were being invaded.

Now, imagine Planet C, which is identical to Planet A, except it is 1% older, or 45 million years further along the evolutionary path.  If C inhabitants came to A, would the inhabitants of A even necessarily recognize what they were seeing?  And if they did, what are the chances that they’d have any effective defenses against an invasion?

Of course in reality, even in the extremely unlikely event that another world was Earth’s identical age, the randomness of things like a different sized star, a different distance from that star, different chemistry, different mutations, different timing of asteroid strikes, volcanic eruptions, and an infinity of other factors would guarantee a unique timeline and development for that world.

If we do encounter extraterrestrials, from our perspective, they will either be, at best, animals we wouldn’t regard as intelligent, or gods.  The probability that we would meet a civilization anywhere near us in development, close enough for there to be any kind of real contest between the two of us, is virtually zero.

When thinking about contact with a more advanced civilization, we should bear in mind the way that we’ve historically treated creatures far less intelligent than us.  While we’re beginning to think that maybe we should treat chimpanzees better, most of us still have no problem with treating most of the rest of the animal kingdom as a food source, as beasts of burden (slaves), pets, experimental subjects, or nuisances to be exterminated.

Belief that a more intelligent species must be benevolent is a nice idea, but I can’t see any reason to suspect it must be true.  Any intelligent species would have had to evolve in a competitive environment, just like we did.  And just like us, their instincts toward less developed life forms would likely be to regard them as slaves, experimental subjects, nuisances, or at best, pets.  (There’s little chance they’d be interested in eating us however, since the probability of their chemistry being compatible with ours is likely nil.)

This is one of the reasons that initiatives like Active SETI have always struck me as profoundly misguided.  Shouting out into the wilderness may have consequences for our posterity that we can’t imagine.

The good news is that the Fermi’s paradox indicates that, while there is a good chance of life elsewhere in the galaxy, there probably aren’t a vast number of civilizations out there.