Noted astronomer Frank Drake passed away earlier this month. Among his many, many accomplishments was a venerable equation with which many SF fans are familiar:
N = R* ⋅ ƒp ⋅ ne ⋅ ƒ1 ⋅ ƒi ⋅ ƒc ⋅ L
N is the number of civilizations in our galaxy with which communication might be possible. Depending on the values one plugs into the defining factors, N might be anywhere from very large to very small. Very conveniently for science fiction authors, every possible value of N from very small to very high is filled with story potential. Here are five stories reflecting some of those possible solutions…
(A) The lowest possible value of N at the moment is 1. Our civilization currently possesses several means by which it could make itself known to the galaxy at large, ranging from radio signals to nude selfies with directions to our home, addressed “to whom it may concern.” No answers. Yet. It might well be that we are not alone at the moment, just the very first technological civilization to appear.
Emily Skrutskie’s 2018 Hullmetal Girls features a Milky Way in which not only is intelligent life vanishingly rare, so are habitable worlds. Unfortunately, humans did not fully grasp that no Earth 2 was at hand until Earth 1 had been thoroughly trashed. In the centuries since the fleet fled the Solar System, scouts have found no worlds suitable for human settlement: even the so-called Alpha worlds, the most habitable available, are anoxic death traps.
Maintaining the fleet in the face of meagre resources demands regimentation, or so those commanding the fleet believe. The elite cyborg Scela are a key part of maintaining order. Life as a cyborg demands sacrifice, but there are many means available to convince suitable teen candidates to embrace conversion.
(B) N could higher than 1 but still low. Communication may be possible, but the time lags imposed by light speed suggest that whole civilizations could rise and fall in the interval between signaling the nearest neighbor and receiving a reply. Communication with Extraterrestrial Intelligences (CETI) might consist only of assurances that ETIs do (or at least did at the time of broadcast) exist, rather than any sort of meaningful communication.
David McDaniel’s 1974 novelette Prognosis: Terminal explores this in passing. Its protagonist, a struggling artist, searches for a viable niche. Alas, technological progress and social change have eliminated many traditional artistic roles. In many stories, the solution might be to turn to the stars. However, a signal from a long-dead alien civilization reveals that the far more advanced species failed to develop interstellar flight despite its star’s impending nova. The implication is that if solutions for the human condition are to be found, they will have to be found on Earth.
(C) There is the possibility that N could be high enough that occasional conversations are possible but rare. Even if the average distribution is too widespread for routine conversation, some pairs of civilizations will be closer than the average, while some civilizations may possess time-binding abilities that facilitate two-way communication carried out over surprisingly lengthy intervals.
As far as the humans of Der-Shing Helmer’s Mare Internum (2019) know, Mars is a dead world. Appearances can be deceiving. Mars was not merely the abode of life well before Earth but home to an advanced civilization as well—human astronauts owe their existence to careless Martians spreading life to young Earth. Indeed, life still exists within a last refuge deep beneath Mars’ surface. Thanks to some very poor life choices, Doctors Mike Fisher and Rebekah “Bex” Egunsola will experience the wonders of lost Mars in person.
(D) N could be high enough that interaction between unrelated civilizations is commonplace, if not necessarily routine. This is something of a sweet spot for science fiction authors, so examples abound. This value of N does raise Fermi Paradox concerns (if aliens are so common and can reach Earth, where are they?) but these are easily dealt with in various ways, not least by simply ignoring them.
The intrepid explorers of Stanley G. Weinbaum’s “Martian Odyssey” (1934) and the sequel “Valley of Dreams” (1934) find a Mars rich with a bewildering variety of alien life. If the greater facility with which birdlike Martian called Tweel bridges the communications gap is a guide, some of that life is smarter than humans. In fact, the humans belatedly discover that the similarity between Tweel’s people and the Egyptian god Thoth is no coincidence; Martians (or at least Tweel’s sort of Martian) visited Earth in antiquity.
(E) Finally, N could be very large. The Milky Way could be crammed with intelligent life, waiting for us to overcome whatever comprehensive blind spot is preventing us from noticing them, and for rich, plot-friendly interaction to ensue. Indeed, one could envision humans equipped with star-spanning super-science engaged in a mind-boggling enterprise, some manner of multiyear mission to go where no one has gone before, not counting the myriad aliens they encounter each week, who presumably were there all along. Not entirely sure what one could call a story about trekking from star to star but I am sure some appropriate title will come to mind. Galactic Wagon Train, perhaps.
In Mary Gentle’s 1983 Golden Witchbreed, Earth has, by virtue of a very large value of N and a faster-than-light drive capable of spanning the Milky Way in three months, found itself with an embarrassment of CETI riches. There are millions of civilizations with which Earth could open relations. The challenge appears to be finding a sufficient supply of functionaries to conduct diplomatic relations.
As Dominion diplomat Lynne de Lisle Christie discovers, the real challenge is ensuring that Earth actually understands the alien civilization before dispatching its diplomats, rather than, as in the case of Orthe (the world to which Christie is dispatched) jumping to a plausible but wildly incorrect conclusion. Overcoming cognitive blind spots can be a rich source of personal growth … but only if you survive the experience.
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Of course, solutions for the Drake Equation open the door to many narrative possibilities. The five works noted above are only convenient extremes chosen for demonstration purposes. No doubt there are intriguing cases I’ve overlooked, cases readers may wish to discuss. Comments are, as ever, below.
In the words of fanfiction author Musty181, prolific book reviewer and perennial Darwin Award nominee James Davis Nicoll “looks like a default mii with glasses.” His work has appeared in Publishers Weekly and Romantic Times as well as on his own websites, James Nicoll Reviews (where he is assisted by editor Karen Lofstrom and web person Adrienne L. Travis) and the 2021 and 2022 Aurora Award finalist Young People Read Old SFF (where he is assisted by web person Adrienne L. Travis). He is a four-time finalist for the Best Fan Writer Hugo Award, and is surprisingly flammable.
ISTR that there was a Poul Anderson humourous short story in which the N-value was very high. There was a peaceful Galactic Federation that was aware that Earth was getting close to hitting the membership requirements BUT didn’t want to contact us. Because of our violent nature? Interstellar cooties?
Nope. Adding a new member was expensive and inconvenient, and they discouraged contacting ALL potential new members, not just Earth. Needless to say, plucky humans in the know were able to trick the Federation into letting us join.
Can’t remember the name of the story, though.
“Our civilization currently possesses several means by which it could make itself known to the galaxy at large,”
Unfortunately, I think recent studies have shown that no matter how powerful a signal we send, it is attenuated to background noise well before it could reach any potential recipient. To be detectable over galactic distances, the signal must truly be epic in scale (like a network of Dyson shells).
Although that might be a useful followup topic–what kind of signals would really be detectable over such large distances and have any SF authors dealt with it realistically.
2: My memory is that the study was talking about inadvertent signal leakage from Earth, but that deliberate efforts with tools like radio telescopes, military radar, and exoatmospheric nuclear detonations could be visible at extreme ranges.
“xoatmospheric nuclear detonations”
So using all the atomic bombs in the world (Estimated at 13,000) we could send a 1600 byte message to the universe. That’s about the length of a single Tweet. What would we say?
@@.-@
All your base are belong to us
“We of Earth had terrible judgment.”
That `equation’ sounds more like a conversational gambit then anything else. (I mean, it is counting or probability at a early high school level, rather than an equation like newton’s laws, or something that describes a constraint on various ostensibly distinct measurable phenomona).
Fun rather than deep. A bit like checking you have enough money in your bank account before going shopping. All terms need defining, and you do need to do it.
Has anyone been able to take this kind of thing somewhere serious? (Even to funding bodies?)
Anyhow, thanks! TIL
At this point in the game, we have a dearth of information on which to build reliable models. However, there have been serious, legit searches for intelligent life elsewhere in the universe going back to Drake’s own Project Ozma:
https://en.wikipedia.org/wiki/Project_Ozma
It’s an example of how science marches on: these days Epsilon Eridani would not be considered a prime target for CETI because the system appears to be less than a billion years old.
Piers Anthony’s Macroscope basically went with “N is large, but there is a dog in the manger”. Once the Macroscope was invented, it was found that there are many many communication channels in use on it … but to use the Macroscope you must first survive a killer transmission, that seems to eliminate only smart people.
Wrong. N is the number of expected technical civilizations in any particular galaxy. It is entirely possible that N = .001, and that just means that you have to search through a thousand galaxies to find one, and the Milky Way happens to be the galaxy that contains it. I think that entirely the most plausible explanation for the “Fermi paradox” is this.
(Isaac Asimov once wrote an article analyzing the Drake Equation. He argued correctly that it would be a very striking coincidence if all the factors happened to cancel out, leaving an N on the order of 10^0: N ought to be very small or very large; and since its minimum was 1 it could not be very small, and therefore should be expected to be very large, perhaps something like 10^8. This was Asimov’s fallacy: in fact our existence does not set the minimum at 1.)
This of course raises the question of which of the factors is driving the total down. On good days, I think that fi is very low; on bad days I think it’s L.
Its not really SF but your title was too similar, The Search for Signs of Intelligent Life in the Universe was one of the funniest plays I ever saw. One woman play in 1985 (revival in 2000) by Lily Tomlin, written by Jane Wagner. It was made into a movie and a novelization a couple of years later, not as good as the play but still worth finding.
Basically we’re all bag ladies wearing umbrellas on our heads
@1: Perhaps “Peek! I See You!” – though that has a southwestern US Pueblo as a member of the federation.
https://isfdb.org/cgi-bin/title.cgi?50543
I like the name “,Galactic Oregon Trail” myself. Look out for interstellar dysentery!
James Gunn’s The Listeners is about a SETI experiment that pays off. We receive an interstellar communication from the star Capella. After much debate, we send a reply, and 100 years later we get a response. I’ll leave the rest for a reader.
Norman Spinrad’s Riding the Torch also deals with terrestrial survivors who discover habitable planets are really rare. The story concludes on a note to warm a classic SF fan’s heart.
Thanks for the link JDN @8.
I learned that the `conversation starter’ aspect is the point. Saying that the probability of life elsewhere depends on (explicit) list of factors will get met with disinterest. I mean, yeah, obviously.
Make them an `equation’, and you have a media (and politician) friendly statement! It is `science’. No one who understands thinks you are speaking bull – or saying anything controversial at all. Non-numerate types get a little intimidated, or impressed.
And in this case you get the actual funding to see if you can discover … something. Which I guess we are still doing, looking for evidence of sapient activity.
I guess initiating, arranging funding, and managing large projects requires superb communication skills, and media savvy. Who knew?
James White’s Sector General series had a good rationale for emergency situations being the most likely reason for contact with aliens – one-shot subspace distress beacons that transmitted with much more power than regular messages. Of course the recipient needs to be (a) able to receive subspace messages and (b) able to help, in the Sector General series that wasn’t a problem because they had ambulance ships and a “code of the sea” equivalent that meant that most people receiving the signal would try to help.
In the first of Julian May’s Galactic Milieu books, Intervention, people who have developed psychic powers band together under attack by fearful “normals” and send a distress call to the Galactics they hope are out there — they don’t actually know if they will be heard.
The Cassiopeia Affair by Chloe Zerwick , about first radio contact
Story “The Crystal Spheres” by David Bron, about the scarcity of civilizations
I remember a story in which there were hundreds of civilizations in the Galaxy, all listening for First Contact, but none, for a variety of reasons, actually sending.
On the other hand, there is a novel, “The Voice of Cepheus”, by Ken Appleby, in which humanity starts receiving messages from another civilization, ostensibly offering friendship and co-operation, but actually with a considerably darker purpose (now read on).
There was a British TV serial, “A For Andromeda”, and its sequel “Andromeda Breakthrough”, which involved scientists operating a radio telescope receiving a complex radio transmission from space. Managing, after considerable effort, to decipher it, they find themselves able to build and program an AI (not that that term was used in the1960’s) – effectively, an “Andromedan” representative on Earth.
Unfortunately, one of the first things the AI does is to release a micro-organism into the world’s oceans that starts absorbing the oxygen from the atmosphere – not quite what was hoped for..