Do human beings share the Universe with other intelligent civilizations or are we alone? The revelation that planets outnumber the innumerable stars suggests that habitable worlds must exist somewhere. The vast number of possibilities invites the hypothesis that somewhere out there are planets harboring intelligent life.
Scientific discoveries have systematically dispelled all notions that planet Earth is exceptional. The heavens may seem to revolve around us, but the data confirm our beautiful home is quite modest by celestial standards. The latest results, while demonstrating our home planet is only one of a vast multitude, have invigorated discussions regarding the search for extraterrestrial intelligence (SETI).
The numbers give SETI investigators (1) hope they will ultimately discover evidence other intelligent beings exist in our galaxy. Searches have been conducted, but have yielded only false alarms and the inexplicable Wow! signal (2). Although the current findings suggest intelligent life is rare, only a tiny portion of the galaxy has been examined and briefly at that. It is too early to declare with any confidence we are alone.
Maybe we have not been looking for our neighbors in the right ways. Instead of seeking the needle in a gigantic cosmic haystack, deliberately announcing our presence through optical or radio signals might be a more fruitful approach and generate a quicker reply. A new group operating as METI – Messaging Extra Terrestrial Intelligence – proposes to initiate this more active strategy in 2018 (3).
But is the METI effort wise? Any reply would be a stunning scientific result, but is revealing our location risky? Opinions differ and the debate has surprisingly far reaching implications. If we do have tech-savvy neighbors and they elect to respond to our overture the scientific implications of contact are incalculable. But what happens if we draw the attention of beings far more advanced than us? Will they be benevolent or might we come to regret this action? Look at our solar system; eight major planets with only one currently suitable for an intelligent civilization. Perhaps livable planets are rare and someone else would like to have ours, as H. G. Wells envisioned in The War of the Worlds. On the other hand, maybe our neighbors are so advanced that they would have no interest in our planet. Perhaps they were spawned and evolved on illuminated worlds like ours which they abandoned long ago. Or maybe they did not emerge on anything remotely like our Earth. One argument against METI is that the nature and intentions of our neighbors will only be known after they have discovered us. METI supporters counter that humans have been sending electromagnetic signals into space for many decades.
Steven Johnson’s article (3) reveals the complexities and complications involved in undertaking an effort like METI. How do scientists calculate the risk when the unknown factors are so far beyond the bounds of knowledge? Who makes the decision to proceed or enforces an order to halt? Everyone on Earth has a stake in the outcome.
How long do civilizations able to communicate across space survive? Perhaps such beings have already flourished and expired on many of the illuminated worlds around us. Or, more troubling, such beings vanish quickly because they actively engineer their own extinction. Maybe our corner of the Universe seems empty because advanced civilizations inevitably end up destroying themselves through environmental degradation, nuclear war or other means.
The most provocative aspect of Mr. Johnson’s article has to do with the decision-making involved. METI raises profound questions about the persons empowered to make the call for the planet. In the end, this matter will be decided by a tiny circle of experts. However, METI is but one of many momentous wise-use-of-technology decisions facing humankind; will we modify our own genomes, will we re-write the genetics of entire ecosystems with gene drives or continue growth/energy policies that are unsustainable? Although we often hear how the public must be included, the reality is that a small group of experts will drive these decisions. Let’s hope they are judicious or humankind may be long gone if and when a response to our METI call comes in.
Over the past decades support for the SETI effort has been fitful and proactive signaling attempts limited. In 1974, the Arecibo radio message was beamed in the direction of the M13 cluster as a special event. Forty years ago the Wow! signal was detected, a strange occurrence that has never been repeated or explained. Taken together these brief, one-time happenings suggest something; If the Wow! signal is artificial and extraterrestrial, at least when it comes to the fundamental approach toward the issue of finding intelligent life, those beings seem exactly like us.
(3) S. Johnson. 2017 Greetings, E.T. (Please Don’t Murder Us). The New York Times, 28 June 2017. https://www.nytimes.com/2017/06/28/magazine/greetings-et-please-dont-murder-us.html