One cannot stare into the night sky for very long before their mind is filled with questions. The most important and far reaching of these are exactly the questions we first asked as children: How big is the universe? Does it go on forever? What are the stars? Are there more people out there among the stars?
Some of these have been answered in the last few hundred years. We now know the distances to each of the stars we see with the naked eye, what they are composed of, how old they are and a host of other physical properties. We know about black holes, massive invisible structures and sources of energy a billion times greater than our sun. But many of our most basic questions remain hauntingly elusive.
Perhaps the most important question of all these is the existence of other life, intelligent life. It’s been a question of literature and scientific curiosity for as long as written history. The implications of which, could have unimaginable meaning and consequence for our lives, technology, knowledge of God, safety and even our mortality.
Is all of this even a reasonable question? Could intelligent life develop anywhere but earth? If so, how many other civilizations are there? On average, how close would our nearest neighbor be to earth? Would they be friendly or even care about talking to us? Try starting a serious conversation about extraterrestrial life at your next office party or on a first date and see how fast people scatter to get away from you.
Attempts have been made to answer these questions in a serious scientific light. The most famous attempt is the Drake equation. The Drake equation is a series of assumptions designed to calculate the number of intelligent civilizations in the universe. It begins with the number of star systems, a BIG number (Over 1,000,000,000,000 galaxies in the observable universe with about 100,000,000,000 stars each). That is more than ten thousand stars for each grain of sand on all the beaches and oceans of the earth. The rest of the equation is a series of fractions designed to narrow this number down to how many current civilizations. Start with the BIG number, multiply by how many stars have planets (about 1/2), multiply by how many of those planets are the right size and temperature (liquid water) for life (about 1/20), next multiply by how many of those would eventually have simple reproducing molecules & amino acids, then how many of those would form cells, then multicellular life and finally what fraction would evolve enough to produce civilization and sufficiently advanced technology for radio (the most obvious way to communicate).
Admittedly, the last several terms are purely speculative. It’s possible that this is the only planet to ever spawn reproductive forms of matter, or maybe the universe is teeming with life but they are all plants that will never develop large brains. Or maybe some specific step in the evolutionary process is extremely difficult and although simple life appears spontaneously, it never crosses some critical threshold that did occur on earth (the “Great Divide” hypothesis). Of course to us, we can’t know any of these probabilities or even which steps were more difficult than others. Here on planet Earth, they all happened (once)…no big deal.
The Drake equation even adds another term at the very end, a dark harbinger. It’s not enough that a species develops technology to shout their voice out into the universe, they also need to survive long enough for others to hear them and communicate back. For humans, less than 50 years elapsed between the invention of radio communication and the development of nuclear weapons. Only 6 years more brought the hydrogen (thermonuclear) bomb with 1000x the destructive power.
It’s entirely possible that the life expectancy for a civilization is only 200 years from inventing radio until annihilation…
2,000,000,000 years of evolution…
50 years of radio…
Then total extinction for the planet
Perhaps alien civilizations appear frequently, but briefly, like a firefly flashing and disappearing again into the night.
This too is another unknown probability. The Drake equation is simply the framework for educated guessing.
One thing is certain though, because of the sheer size of the first number (stars in the universe), if the other fractions are not zero (even very very small is fine) the total number of alien civilizations is still huge.
This leads to our unsettling question: If there are so many other worlds with intelligent life, why do we hear ZERO communication? Why are the skies so ominously quiet?
This is where the speculating gets really fun!
Microbiology? … ZZZZZ
Nuclear apocalypse?….Too dark for me, thanks…
But take guesses at why aliens would avoid talking to me? Now you have a fun drinking game.
The possibilities here are really wide open.
Maybe they don’t know about us yet. Let’s face it, we only sent our first broadcasts a century ago so. At most, our radio signals have reached 1/9,000,000th of our own galaxy.
Maybe they know, but there’s a galactic etiquette about not disturbing “primitive worlds”. We have our own policy about uncontacted tribes in the Amazon and Asia.
Perhaps they’ve chosen to observe us without actually changing anything. Its likely they would have the technology to send nano-robots to earth to watch and learn everything useful without us noticing (the robots are those little floating things that sometimes get caught in your eye and you can’t look straight at them…I hate those things).
Edward Snowden has theorized advanced communication would all necessitate encryption and perhaps the noise observed by our radio telescopes is actually the chatter of a 1,000,000 worlds.
Others have posited that by listening for radio waves we’re likely used an outdated technology, that aliens used a more sophisticated and efficient technology to communicate. They may use beams of neutrinos that pass effortlessly through planets and stars, eliminating the line-of-sight problem, or a physics-bending technology that isn’t constrained by the speed of light (wormholes or quantum entanglement are both words I know).
Whatever the case might be, no one has said “Hello” yet.
It may also be unwise to start yelling it into the abyss about our nascent civilization. The life forms that developed first would have God-like technology, incomparable to our own. What if they were unfriendly? What if the first world to awake in this universe decided to remove all competition by systematically eliminating new entrants?
Carl Sagan, a proponent of SETI (the Search for Extra-Terrestrial Intelligence), himself vehemently opposed efforts to send an ultra-powerful message into space announcing our world to the galactic community. While he advocated funding and popular support to search for the communications of alien life forms, his support was limited to quiet listening. All attempts to send communications (beyond the radio, TV and cellular technology already in use), were to Sagan, a direct threat to our survival as a species.
Carl Sagan was right to associate danger with contact. Near omnipotent technology could bring an end to human suffering or an end to human life. What would we know of the intentions of such as different and advanced race? The most likely scenario is actually that they wouldn’t care at all, that we would offer as much opportunity to trade or learn as a few microbes on an ant hill in Africa. Or not.
Within our own species, when a group was contacted by outsiders with even a slight technological gap of 50 or 100 years, enormous change always ensued. Many of the changes were positive, new medical technology, trade and greater awareness. Other effects were some of the darkest in our history: slavery, disease, social turmoil and often the complete annihilation of a people, sometimes intentionally.
It’s impossible to conceive what Contact with another civilization would mean to our existence. For one thing, it’s never happened so we have no precedent other than our own stories of exploration. We can’t fathom their abilities or intentions. Further the enormous scope of our technology as a species has only come about in the last 10,000 years or so. As we developed written language and formalized a systematic pursuit of knowledge the pace accelerated. What would constitute a civilization 5 or 15 million years senior to our little planet?
In our experiments with technology…the first airplane flew barely a century ago, 33 years later we had high altitude military aircraft, 33 years after that men landed on the moon. A mere 66 years separated our first flight (40 meters in length and 2 meters in altitude) until we were a space-faring species. What would that exponential advance look like after another 150,000 centuries?
And 15 million years isn’t even that much! That would be a race that reached our level only 0.1% earlier than us (since the start of the universe).
This is the part where I’ll make a contribution to the list of reasons…
If the universe is full of civilizations why is it so silent? A humorous thought occurred to me…
Carl Sagan’s conclusion is a very wise one. To announce your existence is to risk ending it. If we, radio-capable for only 125 years ago, were to actually make contact we would certainly be the junior player to our new friends. We would be totally at their mercy.
Considering this, it’s very possible that an intelligent civilization would make a collective decision to remain quiet. Sure they would have communication technologies but they would limit their amplitude to the species’ home planet(s), would encrypt them to be indistinguishable from random noise and would use bandwidths similar to cosmic rays and background heat. They would explore, expand and trade but only in their own sphere of influence.
If this is a logical conclusion, it would be reached by many (nearly all) worlds. Each would sit quietly in their little part of the galaxy too afraid to speak.
What I find really funny about this idea is that even the first, most advanced and militarily-fearsome race would assume that it’s too improbable that they were in fact the first, and chose instead to be quiet in fear of a predecessor that doesn’t exist!
Naturally, not all worlds would chose this path. A minority (maybe 1%) would still naively communicate, shouting out their existence into the dark night. Let’s look at an example planet ‘Beta’ that chose to roll the dice and say ‘Hello’.
Soon Beta’s message would reach the other nearby neighbors each sitting with lips pursed. Choosing a civilization randomly, there’s a 50% chance the signal would reach a planet less advanced…call it ‘Gamma’. The Gammatonians, listening via their university funded SETI programs, would learn they are not alone. They observe the Betamax broadcast and quickly realize the Betas are a million years ahead of them (literally). It is profitable for the Gammadors to gain technology and insight from these messages, but they also confirm their fears. Despite the Betas seeming peaceful and curious, technological disparity makes the risks contact too great. The Betas will not learn of the Gammas.
Not long after this, the Beta broadcast reaches another planet, this one is more advanced, the Alphas. The Alphas also quickly decipher the message and learn of world Beta. But unlike the Gammas the Alphas need not fear. Their world is no match for Beta. In fact, beyond the data point that Beta exists, there is only one reason Alpha cares about this message…it’s not smart to call attention to their little neck of the woods.
Beta is only 180 light years from Alpha and their message could attract unwanted attention to this little quadrant of a little arm of a spiral galaxy. Surely there must be other civilizations, predating Alpha. And the Alphonies DO NOT want to meet them.
The Alphonies quickly dispatch a warship of Alphnot soldiers and Alphnaught robots to Beta to politely explain (disintegrating beam) the lack of wisdom in this aggressive ‘Hello’.
Betawin politicians and generals quickly agree with the Alpha Females’ demands and cease communication.
And thus the story repeats itself, time and time again through the universe. Each alien race before us, hides in fear of the races before them. When a rare outlier chooses the path of communication, the nearest older race to hear their message promptly shuts them down and the pattern continues…
A universe teeming with life, all too fearful to pick up the phone.
The most Powerful & Ancient of them all, paralyzed with fear of the non-existent force predating Them.
A silent sky…