Should Earth Try to Phone ET? Experts Clash Over Risks of Alerting Aliens

By Glen Martin

If there’s an appropriate place to apply the Precautionary Principle, beaming high-powered messages to exoplanets that could support intelligent life might seem a good place to start. Or maybe not. It all depends on one’s cosmic perspective.

As most ET buffs know, the idea of METI (Messaging to Extraterrestrial Intelligence) is SETI (Search for Extraterrestrial Intelligence) on steroids. SETI, of course, refers to the long-running effort to detect alien civilizations via the scanning of interstellar radio frequencies. METI kicks that process up from the passive to the active by trying to contact ETs directly via powerful radio dishes or lasers. The question lurking beneath the surface is one that has deeply embroiled both astronomers and Trekkies: Do we really want to let extraterrestrials know we’re here?

What if they’re not the Steven Spiel­ber­gi­an kewpie doll kind of ali­en, but in­stead the froth­ing, ooz­ing-chartreuse-slime-from-every-pore, face-eat­ing vari­ety?

What if they’re not the Steven Spielbergian kewpie doll kind of alien, but instead the frothing, oozing-chartreuse-slime-from-every-pore, face-eating variety?

Citing sobering concerns, more than two dozen experts from the University of California and elsewhere have now signed a statement urging that Earthlings exercise caution before advertising our existence—insisting on “a worldwide scientific, political and humanitarian discussion…before any message is sent.” But others want to proceed, among them Seth Shostak, director of research at the SETI Institute in Mountain View, who recently publicly labeled fears about METI “overwrought.”

To some degree, of course, METI already is underway. In 1974, a pictogram was squirted into the ether by the massive radio antenna at Arecibo, Puerto Rico. In 1999 and 2003, a team led by Russian astronomer Aleksandr Zaitsev transmitted powerful “cosmic calls” from the Yevpatoria Planetary Radar in Crimea. A Doritos commercial was broadcast to a star 42 light years away by the EISCAT European Arctic transmitter in 2008, and NASA beamed the Beatles tune “Across the Universe” toward the North Star in the same year.

But those are just initial yawps; we may be on the cusp of a METI explosion. Certainly, the means are there: The Arecibo dish literally is capable of transmitting the equivalent of “Yo, Dude,” across the galaxy. And technological advances are such that backyard radio astronomers could send their own messages into the void in less than two decades.

Any civil­iz­a­tion we con­tact could be mil­len­nia or epochs ahead of us; it would thus be un­likely to view us as a threat, just as we are un­in­tim­id­ated by mewl­ing kit­tens.

And the will to yammer on a cosmic scale—at least among a certain cohort of scientists—exists as well. In a recent op-ed in The New York Times, Shostak argues that space is vast and communications “won’t be breezy,” taking decades to establish even a minimal back-and-forth colloquy. Second, any civilization we contact could be millennia or epochs ahead of us; it would thus be unlikely to view us as a threat, just as we are unintimidated by mewling kittens.

Shostak also reasons that a METI moratorium would put undue research constraints on our “children and our children’s children.” And finally, he avers, the horse is out of the barn anyway: “Any extraterrestrials with technology advanced enough to threaten us will surely have antennas larger than our own, instruments that can pick up the television and radio signals broadcast willy-nilly since World War II.”

Not so fast, counter METI skeptics. That class includes UC Berkeley astronomy professor Geoffrey Marcy and Dan Werthimer, the principle investigator of the UC-sponsored SETI@home, director of the Center for Astronomy Signal Processing and Electronics Research, and an associate of the UC-supported Berkeley Wireless Research Center. Both men have signed the petition urging a go-slow approach to METI (as have several other luminaries, including Elon Musk and astrophysicist-cum-bestselling-sci-fi author David Brin).

“The great majority of astronomers think that transmitting is a terrible idea,” says Werthhimer. “METI was discussed at length at a recent AAAS [American Association for the Advancement of Science] conference. Each speaker got up and discussed pros and cons, and then we took an informal poll. The overwhelming majority opposed active messaging—maybe two supported it. So there are only a few people in the science community who think, ‘Oh, there’s no risk,’ and seem intent on taking it upon themselves to speak for the entire human race. Because that’s what [a focused, high-powered] transmission amounts to. One person could cause consequences for the entire planet.”

So far, says Werthimer, no governmental body oversees METI, and no formal regulations apply to it.

“Most of us would like the National Academy of Sciences to look at the risks and potential benefits and issue guidelines, just as guidelines are issued for other potentially dangerous research, such as DNA sequencing,” says Werthimer. “In general such guidelines are voluntary, they’re not onerous, but they work very well.”

Scientist and sci-fi novelist Brin also opposes willy-nilly shout-outs to the stars, and discounts Shostak’s contention that radio and TV leakage over the past 80 years are comparable to focused METI blasts.

“Our best calculations show that it would take prodigious alien [receivers] to detect earthly radio, TV and radar transmissions, even those from the 1980s, which were our ‘nosiest’ decade,” Brin says. (Off-planet transmissions have waned significantly from that period due to the switch from broadcast to cable and fiber optic transmission modes.) “Focused transmissions magnify detectability by a factor of 10 million.”

But how much of a potential threat do aliens pose if we can’t even find them? SETI searches have been conducted since the 1960s, and so far we’ve heard nothing that could be construed as anything other than cosmic background noise—pulsars, quasars, star-gulping black holes—but no ET equivalent of I Love Lucy.

Brin, who debated Shostak on METI at the recent Conference on World Affairs in Colorado, concurs that the interstellar jungle seems devoid of the bird screeches and primate hoots that you’d hear in its terrestrial analogue; and yes, that may be because there are no extraterrestrial birds and primates to screech and hoot. The deafening silence could simply reflect an utter absence of intelligent life.

But it may mean something else—namely, that the denizens are deliberately keeping quiet. The intergalactic ecosystem may support more than placid, highly evolved grazers and browsers. Predators could be stalking.

“Maybe they know something we don’t” says Brin.

Most SETI researchers agree that trying to figure out possible alien motivations is a bootless endeavor. Who knows why they would be either friendly or hostile? If the latter, their rationale could range from a fear of long-term competition for galactic resources to a basic cultural imperative: They may find intelligent species other than their own innately repugnant. Or perhaps they are gourmands: Maybe unfamiliar intelligent life forms are their equivalent of Beluga caviar. In any event, the “why” of any response, benign or antagonistic, would likely remain unfathomable to mere Earthlings.

But even if the aliens got a burr under their saddle, what could they do about it? Any civilization we contact is likely to be scores—or hundreds, or thousands—of light years away. Don’t such vast distances equate to safety? Not necessarily.

“Say they’ve learned to accelerate matter using anti-matter,” says Brin. “That’s a technique that could be within our own capability in a century or so, and it could be used to push material at 1/10 the speed of light.”

At those velocities, a chunk of iron the size of a Manhattan skyscraper could reach Earth from a distant star system in mere decades or centuries. Calculating an intersection point with the Earth’s orbit would be relatively easy, says Brin. And if such a wad of metal moving at such a clip hit our home planet, Brin says, “It could pretty much wipe everything clean down to the bacteria level.”

To that the trepidatious layperson can only add: Yikes. So maybe it’s a good idea to muzzle the radio dishes, hunker down, and shut up? Don’t count on that happening. The number of scientists who want to transmit are in a minority, but they are a determined minority. Requests have been made to NASA and the National Science Foundation, the joint administrators of Arecibo, to transmit from the radio telescope between routine scans for potentially dangerous asteroids. And nobody knows, of course, what the Russians will do. Plus, the Chinese are building a radio telescope that will dwarf Arecibo, greatly expanding the range—and the temptation—for interstellar outreach. Then there are all those amateur SETI buffs who may be able to order interstellar transmission kits through Amazon by 2030 or so.

“All we’re asking,” says Werthimer, “is for people to think about this. Just think before you transmit.”

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Another most provocative post Glen, it reminded me of Pogo’s 1970 Earth Day conclusion “We have met the enemy and he is us.” Sadly, today we are still arguing about “Physicists Battle over Meaning of Incontrovertible in Global Warming Fight ” Relative to “Just think before you transmit” humans may well have the best brains on the planet, but thinking is most definitely not our strong suit.
Agreed, Anthony: Pogo certainly remains a beacon in the gathering darkness. I miss that l’il possum!
Glen, actually the “Gender Assumptions” issue taught me that women are wired to be way better thinkers, especially about the most important survival strategies than men, as latest fMRI studies are also proving. So let’s figure out a way to let women take over before too many tipping points topple. By coincidence there was an NPR 13.7 post today on this subject: “Is It Sexist To Say That Women Are Superior To Men?”

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