This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
SETI, or the Search for Extraterrestrial Intelligence, is typically thought of as an attempt to detect signals—usually radio or optical waves—from alien civilizations. But in 1974, Frank Drake used the giant Arecibo radio telescope, in Puerto Rico, to send such a signal in the direction of M13, a globular cluster of stars 25,000 light-years away. Drake chose such a distant object in order to minimize the risk that someone potentially hostile might be listening, while demonstrating proof of concept.
Now some SETI researchers are doing it again, in an effort they call METI, short for Messages to Extraterrestrial Intelligence—and it’s still risky. Based upon absolutely no evidence whatsoever, METI proponents insist that ET must be benign. If ET is not, we are utterly unprepared for the consequences.
In fact, we are unprepared even for what happens if we simply detect a signal. Provided that an extra-terrestrial civilization (ET) exists, its detection in the near future is orders of magnitude more likely than has been the case in even the recent past. Radio searches have attained vast improvements in backend computing power, bandwidth, and detection algorithms, and now we search for lasers as well as radio beacons. The search for extra-terrestrial intelligence (SETI), habitually starved for money, is better funded today than ever, thanks to a $100M 10-year commitment from Yuri Milner’s Breakthrough Foundation. Added to this is the Chinese intention of using their new radio telescope, FAST, in part, for SETI. FAST is now the largest single dish radio telescope in the world, with more than two and a half times the collecting area of Arecibo.
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Leakage of our television broadcast signals from the 1950’s has by now washed over more than 10,000 stars, and this so called “I Love Lucy” radius increases by one light year per year. Should any of those stars harbor technological life, it might have detected our signals, and may consequently be even now sending its response. These nearby stars may suddenly light up with incoming messages.
Added to this, there is a growing belief that ET may be much closer at hand than assumed by most previous searches, which have focused almost exclusively on stars. Leading SETI scientists have recently considered adding asteroids to its target list in recognition that ET may have sent physical probes to our Solar System. Such probes could hold vast amounts of data on the equivalent of a hard drive. It would be much cheaper to launch information-rich probes than to beam an equivalently information-rich message continuously to Earth over potentially eons. Probes eliminate the problem posed by the term “L” in the Drake equation—that is, the average length of time a technological civilization survives—because they might long outlive their progenitor civilizations.
Probes might also be much easier to find than interstellar beacons: because of their relative proximity to Earth, their signals might be stronger. If extant, their signals should be more numerous than interstellar beacons simply because they would have only a single target, Earth, rather than slewing among potentially millions or billions of targets—dwelling on Earth only infrequently and for little time. Multiple civilizations might have sent probes; and a single civilization might have sent updated versions at regular or irregular intervals. Even if updates (version 2.0, 3.0, etc.) were sent only once in a million years, probes would pile up over deep time. If they exist, it is possible that these probes have lain dormant for eons, but are being awakened by our EM radiation. They might be broadcasting to us now—or one might simply pick itself up and land on the proverbial White House lawn.
Planning for what we will do in advance of making an ET detection is highly preferable to reacting in haste after the fact. There are a host of as yet unaddressed policy decisions to be made. What information should be released to the public? There will be the fact of a detection, the information embedded within its signal, and the coordinates of the detection. Should all of that be released to the general public? Who should decide?
After all, release of the coordinates invites an unauthorized response by parties interested in advancing their own parochial message, while Earth as a whole should be allowed to decide whether to respond at all. In the absence of an agreement or treaty, will the Chinese treat an ET detection in the same way as the West, or simply regard even the fact of a detection, much less the content, as a state secret? Who has the right to determine whether to respond and what that response might be?
If an ET probe is physically encountered on an asteroid by a mining party, or if it lands on Earth, who owns it, and in whose laboratory should it be studied? If it appears to be an intelligent robot, should a probe be afforded all diplomatic courtesies? These, and a host of other issues, have never been addressed, much less resolved, by a governing body such as the Security Council of the U.N., or by any national government.
Underpinning these considerations is the possibility that Earth’s very existence may hang in the balance. We only know two things about the ET we might encounter. First, its technology must be vastly superior to ours. Statistically, the probability that ET also happens to be in its first century of being capable of sending and receiving signals (or probes), is far less than .01, given the age of the universe.
Second, ET’s presence is not obvious. Given that alien civilizations are almost certainly vastly superior to ours, then it is an abiding mystery as to why we cannot readily see evidence for their existence—such as huge architectural projects visible from inter-stellar distances; or their presence as colonizers in our Solar System; or the fact that we haven’t yet detected their intra-galactic communications, (even if those messages are not intended for us). Could it be that ET knows something that we do not, namely, that it is life-threateningly dangerous to reveal one’s presence?
After all, a civilization with malign intent that is only modestly more advanced than we are might be able to annihilate Earth with ease by means of a small projectile filled with a self-replicating toxin or nano grey goo; a kinetic missile traveling at an appreciable percentage of the speed of light; or weaponry beyond our imagination. This is another argument in favor of probes, which need not reveal their place of origin unless the receiving civilization is deemed benign.
The urgency for planning in advance of an ET detection is even greater, thanks to a small but vocal minority of SETI scientists who have begun beaming high-intensity signals to nearby stars in a deliberate effort to attract ET’s attention—and more who intend to do so in the near future. Because these signals are highly focused, they are orders of magnitude more easily detected than the remnants of “I Love Lucy” broadcasts, which radiate feebly in all directions.
Lacking any methodology for the receipt of a return message (e.g., if they send a message to a star at a distance of 20 light-years, they will need to have a telescope ready to receive a return message in 40 years—and they have no such plan), they assume that ET will find a way to make itself known to us, perhaps by hijacking YouTube from afar. The blind faith of proponents in the goodness of ET, as well as in ET’s omnipotence and omniscience, makes METI far more akin to a religion than science. Moreover, it is simply not the right of a few lonely radio astronomers to decide the fate of mankind on their own. SETI is the science by which we seek to determine the prevalence and nature of intelligent life in the universe. METI is profound public policy making (Russian roulette, really), which is the proper purview of all mankind as expressed through its representative bodies.
Therefore, I offer the following recommendations:
1. A high level study of SETI, METI, and post-detection protocols should be undertaken, bringing together experts in such diverse fields as astronomy, computer science, biology, history, economics, civil emergency planning, security and military planning, ethics, diplomacy, law, and others. This committee—a SETI congress, really—would be tasked with making recommendations of appropriate government funding levels for SETI, post-detection protocols, and the treatment of METI. This congress
might best be organized under the auspices of the National Academy of Sciences. Alternatively, the study might be initiated by one or more major universities, the Breakthrough Foundation, the Royal Academy, the SETI Institute, or the United Nations, acting alone or in concert.
2. Pursuant to the recommendations of this
congress, regulations would be promulgated at the agency level (e.g., proscribing the use of radio telescopes for the purpose of transmitting unauthorized messages, i.e., METI), laws at the national level, and treaties internationally.
3. A permanent and ecumenical group would remain in place to coordinate post-detection activity such as follow up confirmatory studies, message decoding and construction, communication to the public, and to advise policymakers. Presumably, this standing committee would report to the U
.N. Security Council.
The SETI of today is not your grandma’s SETI. Modern searches accomplish more in a single day than they used to in an entire year. The discovery that we are not alone in the universe will affect mankind in incalculable ways. As a society, we should plan with open eyes and forethought for the day when we will take our place as a junior member of the galactic club.
Recent Papers
ET Probes: Looking Here As Well As There
Reviewing METI: A Critical Analysis Of The Arguments
Post-Detection SETI Protocols & METI: The Time Has Come To Regulate Them Both