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by Bryan Walsh
In an effort to speed up the search for extraterrestrial intelligence, some researchers are sending messages into the cosmos. We may not like the answer...
The hope is that there
are extraterrestrial intelligences out there trying to message us,
and we just need to be ready with our radio telescopes to hear,
ready for that moment of contact.
Early SETI advocates like the astronomer and author Carl Sagan took it for granted that any alien civilization we might come into contact with would be more advanced than us, likely far more advanced, technologically and even ethically.
(The universe, after all, had been around for nearly 14 billion years before human beings showed up, which means plenty of time for older life forms to arise.)
Given our assumed place as a young species in the cosmic hierarchy - and given all that we might hope to learn from our alien betters - a core SETI belief is that we should listen before we speak.
Shouting into the cosmos, Sagan said, was,
Proponents of what is known as Active SETI, however, believe it's a mistake to assume that any technologically mature alien civilization will automatically take the first step to establish contact with us.
If we're not making an effort to signal them, after all, maybe they won't signal first.
It's possible that extraterrestrials are no longer using radio, and that sifting through radio waves while searching for alien life is like trying to find evidence of other people in 2018 by looking for smoke signals.
Perhaps they assume our
silence is a sign that we just don't want to talk, which means it
would be up to us to start the conversation.
was "deeply unwise and immature," the act of a toddler calling attention to themselves.
Despite the beliefs of people like Sagan, however, SETI has often included the occasional effort to send a message into space.
The first known attempt was undertaken by Soviet scientists in 1962.
Laugh now, but that's
really no different than Carl Sagan assuming alien civilizations
would have the same values as Carl Sagan.
To commemorate the rechristening of the Arecibo Observatory in Puerto Rico, then the largest radio telescope in the world, Drake blasted 168 seconds of two-tone sound toward the star system M13.
It was noise to the listeners in Puerto Rico, but any aliens who happened to receive it might have noticed a clear, repetitive structure indicating its origin was non-natural.
Also encoded in the
message were the numbers one to 10, the atomic numbers of several
basic elements on Earth, and a graphic of the solar system
indicating the planetary origin of the transmission.
Yet just days after the message was transmitted, Martin Ryle, then Britain's Astronomer Royal, sent an angry letter to Drake.
It was,
To this day, mainstream SETI has eschewed active messaging in part out of the concern, however remote, that something malevolent or hungry might be on the receiving end, and that they might come for us.
The editorial board of the journal Nature has cautioned that "the risk posed by active SETI is real," and in 2006, when the International Academy of Astronautics convened a committee on SETI but refused to push for a ban on active messaging, two prominent members resigned.
Before his death, the cosmologist Stephen Hawking was on record saying he didn't think it was a very good idea to invite extraterrestrials to come calling.
It was "very hazardous to reveal our existence and location to the Galaxy," Ryle wrote. "For all we know, any creatures out there might be malevolent - or hungry."
But those fears haven't stopped a breakaway group of space scientists from launching the new group Messaging Extraterrestrial Intelligence (METI), led by the former SETI staffer Douglas Vakoch.
The Israeli-Russian billionaire Yuri Milner's Breakthrough Initiatives - a new attempt to jumpstart the search for intelligent life - has a Breakthrough Message component, with a crowd-sourced competition to devise a letter to the stars.
The interest in active messaging is in part a product of the exoplanet revolution, which has seen astronomers discover scores of potentially habitable planets outside our solar system.
With so many potentially life-supporting planets out there, the thinking goes,
If Drake's Arecibo message was like shouting at random in the middle of a forest, METI can direct signals to where there's a chance of life, including some planets that are as few as 100 light-years away.
Given the vastness of space, METI advocates believe, anything that increases the chances that we might make contact is worth trying.
And they argue that the
risk of active messaging is overstated. After all, humans have been
leaking radio and TV signals into space for decades that could be
picked up by sufficiently advanced extraterrestrial intelligence, so
it's not as if we've been keeping quiet.
If there really are ETs out there silently listening, the signal from METI or one of the other active messaging groups may be the first thing they ever hear from Earthlings. That's an enormous responsibility.
Why should any single group get to decide how Earth says hello - or whether it says anything at all?
Why should any single group get to decide how Earth says hello
- or whether it
says anything at all?
That might be acceptable if the reward is a new search engine or social network. It is considerably less acceptable when innovation brings with it the possibility, however remote, of a world-ending threat.
This is the debate over anthropogenic existential risk, played over again.
Olle Häggström, a mathematician at Chalmers University of Technology in Sweden and the author of the existential risk book Here Be Dragons, thinks so.
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