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:
- 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.
- 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.
- 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?