What Happens When We Detect Alien Life?
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SETI research e’ve never heard a peep from aliens. But improved technology is speeding up the search for extra- terrestrial intelligence (SETI), so what happens if today’s silence suddenly gives way to tomorrow’s discovery? Would the world Wrejoice in the news that someone’s out there? Would euphoria engulf humanity, as Nobel Prizes are doled out like after-dinner mints? That’s one view. But many people think the dis- covery would be hushed up as quickly as a Mafia informant, assuming that the public couldn’t handle the news. Or scarier still, kept secret for fear that an unauthorized response would tell a hostile race exactly where to send their interstellar battlewagons. That’s melodramatic enough. But has any serious consideration gone into what happens when our efforts to detect cos- mic intelligence pay off and we find a blip of a signal in the sea of radio noise WHAT HAPPENS WHEN WE DETECT that pours into the SETI antennas? Some think that addressing that question — even in a speculative way — is hubristic at best and wildly pre- sumptuous at worst. After all, SETI scientists have been torquing their telescopes toward celestial targets for ALINF E LI E? more than half a century without ever detecting such a signal. If we Scientists have been listening for signals from extraterrestrial haven’t won the E.T. lottery in all that time, why worry about what would civilizations for decades, but what would they do happen if we got the winning ticket? if they actually heard one? Simple: SETI researchers are buy- ing more tickets all the time, and the by Seth Shostak chances of scoring the big one keep going up. As computer power improves and new detection technology comes out of the labs, the search is accelerating. Unless the aliens are excessively secretive or simply nonexistent, we could find evi- dence for their presence within decades. So, again, then what? Immediate reactions In the spring of 1960, astronomer Frank Drake performed the first modern SETI experiment, whimsically dubbed Project Ozma after L. Frank Baum’s fictional queen of Oz. What few people realize is The search for extraterrestrial intelligence that he actually detected something. While pointing his (SETI) may not have found anything yet, but it’s important to plan a response, says SETI expert antenna at the nearby Sun-like star Epsilon (ε) Eridani, Drake Seth Shostak — likely the first person to know heard a strong hammering signal. Surprised by how quickly his when the search succeeds. Astronomy: Roen Kelly search succeeded, he wondered, “What do we do now?” © 2013 Kalmbach Publishing Co. This material may not be reproduced in any form without permission from the publisher. www.Astronomy.com The Allen Telescope Array (left) and the Jansky Very Large Array are powerful enough to detect and pinpoint a possible extraterrestrial transmission with a high degree of accuracy. The latter hosts 27 antennas, while the former boasts 42 and plans to have 350 upon completion. Seth Shostak; Dave Finley/AUI/NRAO/NSF scientists had found fossilized martian SETI Institute, and the University of Con- And that’s not all. Two decades ago, microbes in a meteorite. That story ran in necticut found that 72 percent of Ameri- radio astronomers Jim Cordes and Wood- The Sun-like star Epsilon (ε) Eridani was one of Frank Drake’s first targets in his search for extraterrestrial intelligence. Astronomers have since learned The New York Times with billboard-sized cans said they would feel “excited and ruff Sullivan considered what we might that the star anchors the closest known planetary system, depicted in this artist’s conception, but no detectable life. NASA/JPL-Caltech headlines for three days. The public’s reac- hopeful” to learn about a signal from E.T. learn by looking at the subtle variations of tion to the possible detection of life beyond Only 20 percent confessed they would be any alien signal. This includes small fre- Drake answered his own question by happens, a series of additional tests occurs. look promising. This has occurred in the Earth? “That’s interesting. Tell us more.” “anxious and nervous.” quency shifts due to the Doppler effect rigging up additional equipment, and he Eventually, the astronomers running the past and shows the error of those who The meteorite story was a stunted repri- Again, perhaps that’s not too surprising, (which alters a signal’s frequency according soon proved that the throbbing bleats from experiment ask someone at another obser- think that a discovery could be covered up. sal of astronomer Percival Lowell’s reports of given that any transmission we discover to its motion), as well as intensity changes his loudspeaker were terrestrial interference, vatory to verify the detection — to rule out Any real detection would be a headliner, martian canals a century earlier. Again, peo- likely will be from beings many hundreds due to the atmosphere of E.T.’s planet or not Eridanians trying to phone our home. equipment bugs, coding errors, or pranks. everyone agrees. SETI practitioner Paul ple were tantalized, but few seemed to panic. of light-years distant, a seemingly safe simply its daily rotation. Project Ozma could tune to only one The scenario for handling a signal is Horowitz of Harvard University in Cam- remove. And, at first, we won’t know much Careful measurement could theoretically frequency at a time, but today’s SETI receiv- briefly described in a document developed bridge, Massachusetts, says it would “easily Early results more than the signal’s existence. pin down the length of the aliens’ day and ers simultaneously monitor hundreds of under the auspices of the International be the most interesting discovery in human Of course, in 1996 no one felt threatened by millions of channels. Consequently, picking Academy of Astronautics, and referred to as history. Journalists would go wild, at least dead protozoans, even if they were from up a signal is neither remarkable nor rare: A “SETI detection protocols.” These “best for a month or two.” Mars. But SETI searches for intelligent life, If we haven’t won the E.T. LOtteRY in all that few dozen typically come up with each scan. practices” boil down to this: (1) carefully Astronomer Jill Tarter, who heads the and given that human beings are still the time, WHY WORRY about what would happen Naturally, no one gets very excited about verify that the signal is truly extraterrestrial, SETI Institute’s listening efforts in Moun- new kids on the technological block (con- this. Instead, researchers rely on sophisti- (2) inform other scientists and the public, tain View, California, concurs: “The general sider that we’ve only had radio technology if we got the WINNING TICKet? cated software to perform the tedious task and (3) seek international approval before public will be in an excited state for a while, for a hundred years), you can be pretty sure of deciding whether these signals are likely transmitting any reply (see “Abridged SETI fueled by the media. But UFO enthusiasts that anyone we hear will be more advanced But you can bet your paycheck that every year, the size of their world, the presence of to be alien intelligence or (as in Drake’s detection protocols” on page 28). will yawn because they knew it all along.” than us — possibly much more advanced. telescope on Earth will aim straight for the moons, and possibly even information case) just more human-caused radio static. A public reaction of initial enthusiasm, That might sound unsettling, but most transmission. Is a star waiting there? Does it about their atmosphere and magnetic field. Only rarely does any signal survive this Not so fast and not mayhem, has precedent. Consider people don’t see it that way. A 2005 survey have planets? In the rush to learn more, automatic scrutiny. But if and when that These are all patently good ideas that seem the 1996 announcement that NASA by the National Geographic Channel, the even a stalled project like NASA’s Terrestrial Initial questions to suggest that everyone would handle a Planet Finder might see new life as scientists All of that would be tasty fodder for the discovery soberly. However, such interest- shake it out of its comatose state, infuse it technically inclined, but everyone else is ing signals are bound to provoke a response with new vigor, and hurl it into orbit. going to ask an obvious question: What are that’s both messy and confused because There are some things we could learn the aliens saying? That, of course, assumes verification will take many days, at the least. quickly about the signal’s source. Within a that they’re saying anything — that they’ve During all that time, word of the pos- thousand light-years lie tens of millions of included a message in the signal. After all, sible detection will surely spread via blogs stars. Consequently, a few arcminutes sepa- the extraterrestrials might withhold com- and tweets from the researchers themselves rate them in the sky, on average. A high- mentary if they want us to reply first, per- (there’s no policy of secrecy in SETI). So resolution radio telescope, such as the haps so they can gauge what level of you can bet that long before any official Jansky Very Large Array in New Mexico, conversation is appropriate. press conference announcing that we’ve When astronomers announced that a martian has a beam size of about 5 arcseconds at the But let’s suppose that E.T. is trying to tell found the aliens, you’ll have heard about it rock contained fossilized microbes (the tube- commonly used SETI frequency of 1420 us something.