Most every one has heard of SETI — the Search for Extraterrestrial Intelligence — and most also know that, so far, the scientists that operate the powerful telescopes and computers that analyze potential signals from civilizations beyond Earth have come up empty-handed — with the possible exception of the so-called ‘Wow! signal’ (detected only once, for 72 seconds, by Jerry R. Ehman on August 15, 1977).
But maybe it’s high time we moved beyond passive attempts at detection of signals from alien intelligences, and move decidedly forward to the next step: active transmission of messages. This somewhat “next gen” approach (generally called “Active SETI”) is also referred to as METI (Messaging to Extra-Terrestrial Intelligence) and was the subject of a (at times lively) news briefing here at the annual Science (AAAS) Meeting in San Jose, California.
The press briefing — held a day ahead of the symposium scheduled for this Friday morning (Feb. 13, 2015) — offered journalists an impressive panel of four leading intellects deeply engaged in the SETI effort: Douglas Vakoch (director of interstellar message composition, SETI Institute, Mountainview, CA), David Brin (Futures Unlimited, San Diego, CA), Seth Shostak (senior astronomer, SETI Institute), and David Grinspoon (senior scientist, Planetary Science Institute, Tucson, AZ). Each of the four panelists presented his viewpoint and opinion regarding actively transmitting messages into outer space — ranging from the more “gung-ho” attitude represented by Seth Shostak (who feels we should start messaging without delay, given the time it takes for a signal to travel into deeper space), to the far more risk-averse attitude of David Brin. Brin denies that his “camp” is paranoid of an alien invasion, rather, that their concern is with increasing the Earth’s detectability without considering the risks.
Douglas Vakoch spoke to the deep psychological need we humans have to know if we are alone (or not) in the cosmos and the consequent desire to reach out to other potential beings (what underpins the goals of the METI camp), while David Grinspoon reminded attendees that the Kepler (Telescope) Mission has, in just a short time, discovered thousands of new exoplanets — with that number sure to grown to hundreds of thousands in the years to come. As we narrow this field down to more likely candidates — assuming that such candidates are determined — this will also proviide testbeds for directed transmission of messages.
‘Radio Leakage’ verses Active Detection
The panelists urged everyone to consider the ethics of any active transmission effort and, importantly, to ask whose message(s) should be sent? David Brin vociferously asserted the need for a global consensus (on selecting a message) before any attempt be made (if at all). Seth Shostak pointed out we have already begun a more inadvertent (and arbitrary) form of messaging via our relentless radio and television signals propagating from our pale blue dot of a planet. This is termed ‘radio leakage’ in the SETI community and it is, relatively speaking, a recent development (“I Love Lucy is only 70 light years into space”). Vakoch pointed out that the idea of active messaging itself is not new — reminding folks that SETI’s ‘Earth Speaks’ project has been actively inviting people to submit messages that they’d want to send into space since the late 1960’s (interestingly, the most common words in these would-be cosmic messages are “please” and “help”).
METI, however, represents intentional messaging, so, Brin’s cautionary counterpoints to the enthusiasm of Shostak and Vakoch was none-the-less resonant. Many cinematic works exists which point out the dangers of alien contact, and, even if we dismiss these more horrific films (e.g., War of the Worlds, Invasion of the Body Snatchers, Predator, Cloverfield) as sheer sci-fi fantasy, is it wise to assume that no negative impact would ever result from active efforts to communicate with alien civilizations (however far into the future such a consequence may arise)?
“We don’t know that altruism is that common in Nature…and we hope that Aliens would be like us…but what we do know is that every higher animal understands quid pro quo.” David Brin, Futures Unlimited and the Arthor C. Clarke Center for Human Imagination
Though ever-cautious, Brin offered his opinion that nearly every alien intelligence (like nearly every “higher” animal on earth, such as dolphins) would, at minimum, understand quid pro quo and thus exchanges (of some kind) between humans and aliens would be possible. But he then asks: “And what should we trade?” Answering his own question, Brin states: “…the main thing we could have is a trade in information.” But unlike Shostak — “who,” Brin chides, “wants to send the entire Internet…for free!” — Brin asks: “What will we have to sell after that?” Brin argued for a more parsimonious dissemination of out knowledge; advocating for what he calls the “new science of risk analysis”, Brin speculates on his own question, stating: “It may be that there could be no greater sin than to….cast our heritage of knowledge…out there.”
Noting that he and Brin have a few disagreements, Shostak responded by informing the audience that “there is now a statement going around the SETI community that there should be no interstellar messaging without a international consultation…a global consensus.” He then noted that Brin is one of the signatories to this statement and asked: “How do we reconcile this?” To which the skeptical Brin shouted: “Because no one is going to get it!” Brin and others in his camp tend to subscribe to the notion that advanced alien civilizations are extremely rare in the universe (and certainly within our own galaxy), hence his (and others) ambivalent attitude towards the whole active SETI enterprise.
Such were the seemingly contradictory views on display regarding this putative (and rather abstract) active messaging mission. An outsider might be greatly surprised at the level of emotion involved in this debate — or even by the fact that there is such a debate.
In general though, all four panelists did agree that more folks from more walks of life (inside and outside the sciences) need to join in the conversation, as the mission to actively communicate with potential beings from other worlds is a critically important one — from a planetary civilization perspective.
At that point, Vakoch brought up the New Horizon spacecraft which will be sent towards Pluto next year. It is to be the fifth human-made object to leave the solar system and the idea is to crowd-source a message that will be sent along in its memory. In his view, crowd-sourcing the crafting of such a message is the most practical way for interested persons around the world to have a say in the matter, implying also that this could constitute a form of global consensus (as a truly global agreement would be virtually impossible, and time-consuming).
Are We There Yet? How Long to Gain How Much?
So, how much more distance into space would active transmission get us? “Right now, we can only detect ourselves four light years out there, but three hundred years from now,” stated Grinspoon, “we might be capable of transmitting 500 light years into space…but a directed transmission out of Arecibo* (the powerful radio telescope in Arecibo, Puerto Rico) could double that range to 1000 light years.”
Right now, in terms of interstellar communication between civilizations, we depend upon an alien civilization sending a directed transmission to us in the form of (electromagnetic) radiation. But it is possible that some long-lived civilization — doing its own SETI over thousands of years (“on a budget”, as it were) could very well be at a similar level of technology (to us). In Seth Shostak’s view of things: “It is those rare civilizations — like the Klingons — that we could make contact with through a powerful beacon…and whom do not present us with any danger. They can get here and we can’t get there — if that is the concern — that’s centuries away.”
Indeed, active interstellar communication — barring any first contact from a superior alien civilization — would seem to be a game of great patience. But the core idea amongst METI advocates is this: let’s get started, time (and space) is wasting.
*The Arecibo Telescope is capable of generating a powerful transmission signal, as it has three radar transmitters, with effective isotropic radiated powers of 20 TW at 2380 MHz, 2.5 TW (pulse peak) at 430 MHz, and 300 MW at 47 MHz.