By Douglas Marshall
For centuries, the human race has been enraptured with a single question: Are we alone in the Universe? The possibilities are nearly as infinite as the universe itself, and they have manifested themselves in our literature and entertainment culture. Stories such as War of the Worlds, Independence Day, Contact, and of course, the ever-enduring Mars Attacks!, have become staples of our culture. The list goes on for gigaparsecs.
But for all the science fiction, there is a lot of science fact. Astronomers have been listening to the universe since the 1960s, trying to better understand our place in the universe. SETI, or the Search for Extra-Terrestrial Intelligence, is a major modern institution that uses thousands of radio telescopes worldwide to listen for signals that might be of intelligent origin. SETI’s work is important if we, as a race of intelligent beings, are to further understand the universe in which we reside. We’ve been eavesdropping on the cosmos for decades, and thus far, we haven’t heard anything of indubitably intelligent origin. The real question now is, should we ourselves call out?
METI (Message to Extra-Terrestrial Intelligence), is the composition and wide-field broadcast of a radio message bearing humanity’s official greeting to the cosmos… and whoever else may inhabit it. That’s not to say we’d be surprising the universe with our existence; far from it. Our radio and television broadcasts have been leaking out into space since their invention, and even our internet is observable to any civilizations within forty or so lightyears of our solar system. Furthermore, we have intentionally sent messages into the deep black before: the Arecibo message in 1974 and the Cosmic Call in 1999, among others.
Although advanced civilizations in the near (cosmically speaking) vicinity may have already detected our media leakage, detecting a focused radio signal sent in their specific direction is easier by several orders of magnitude. METI would make use of transmitters that emit multiple beams simultaneously, thus sending an identical, concentrated signal to all nearby stars. With the increased number of recipient systems, the probability that someone else is listening increases as well. Think of it as if we, humanity, are on an island, and up until now, only the smoke from our campfire gives us away. Are we ready to build a signal fire, and deal with whatever results of it?
To comprehend the reason behind wanting to call out, one must first understand the Fermi Paradox and its solutions. The Fermi Paradox describes the stark conflict between the outcome of the Drake Equation, which predicted the number of intelligent civilizations in our galaxy to be substantial, and the glaringly apparent lack of evidence for said civilizations. The Zoo Hypothesis, one of the most credible solutions to the paradox, surmises that extraterrestrials are intentionally refraining from interacting with humans for any number of reasons. It could be that we must reach certain technological, political, or ethical standards, or that they have concluded that interacting with us presents unnecessary risks. Whatever the case, there might be civilizations out there. If we reach out to them, we may get a response.
But would that response be a return greeting? Or something far more sinister? Stephen Hawking, a globally celebrated cosmologist, has theorized that an advanced civilization would likely have depleted its homeworld of resources, and would be eager to plunder any nearby worlds to satiate its needs. At the international convention held to discuss the prospect of METI, he restated his caution that “if aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans.”
He is liable to be right. If alien civilizations were to exist, they would almost certainly have a technological advantage millions of years over us humans. And if a malignant race, like one that Hawking has described, detects our friendly hello, we would have no significant defense against an invasion. Not even Will Smith in a fighter jet could deter the marauding cosmic conquistadors.
Even if our extraterrestrial contemporaries are benign, there would be serious repercussions to the less advanced Earthling society. A myriad of issues would inevitably arise as a result of extraterrestrial contact, as detailed by scientist and sci-fi author David Brin in his dissenting essay against unconsulted METI. For now, though, it is simply conjecture. The primary reasoning behind why we should wait on reaching out to our diminutive green neighbors is that we have no possible way of accurately predicting their reaction, and that, combined with our technological infancy, is what is most daunting.
What we should be concerned with presently, argues the greater scientific community, is continuing our search for radio signals. After all, according to the official statement on METI, “as a newly emerging technological species, it is prudent to listen before we shout.”
Header photo by Sweetie187 (flickr creative commons)