Where Are They? Part 1

This is likely to be the first of three postings on a topic that has intrigued me for several years—the prospect of intelligent life on other planets.  Enrico Fermi posed his famous paradox, basically “Where are they?” in 1950.  He was referring to the question of why highly intelligent, highly sophisticated visitors from another planet haven’t visited us here on Earth.  With the tremendous number of planets out there, say 50 to 100 billion in our galaxy alone, surely the chances must be around 100 percent that other life forms have developed, and a small population should have attained the ability to travel the galaxy in some form of advanced spaceship, perhaps with a drive system we can’t even conceive of.  Many planets out there must be older than ours, giving their inhabitants sufficient time to develop space drives that can cut travel time from star to star down to a reasonable value.  And that’s what I want to limit my comments to here in this post—the concept of actually travelling the galaxy.  Keep in mind, I’m not trying to answer the question of “where are they,” just give some possible reasons why they aren’t.

I want to start by looking at the development of life on Earth and see if we can extrapolate into the future.  The Earth is, of course, the only planet we are aware of on which intelligent life has developed, and that could mean it isn’t the best model on which to build an example, but it’s the only one we’ve got so I’m going to use it.  Life began on Earth around 2 billion years ago.  (There’s some evidence life may have evolved earlier than that, but I’m going to use 2 billion as a nice round number.)  In those 2 billion years, life has not once died out completely.  There have been extinctions, sure, and large numbers of species have been eliminated, but life has managed to remain continuous in one form or another since then.  Even the grand extinction which resulted in the eradication of the dinosaurs around 65 million years ago didn’t completely eliminate all life.  Small mammals survived the asteroid impact, and even the dinosaurs themselves were not totally eliminated—they survived into today as birds.  Up to that time, reptiles were the dominant animal life form.  They were the ultimate, the top level, the upper crust.  They basically formed an endpoint, as far as evolution was concerned at that time, and it took an outside event to force a change.  Now, I suppose, mammals are the top animal life form.  We dominate the planet, and have made changes no other animal could ever conceive of making.

Over the last few thousand years, we humans have learned a lot about the universe in which we exist.  We’ve built telescopes which can probe well beyond our own galaxy and see millions of others.  We’ve learned what goes on in the interior of a star, in its core, in the atomic and subatomic interactions which produce the light and heat and all the other emissions that the star puts out.  We can even detect the faint, wispy neutrinos the star emits.  We know there seems to be unseen forces and masses in the galaxy which make up the majority of all mass and energy in it.  We’ve seen stars and planets and asteroids, and even planets that just haven’t had quite enough mass to start the fusion reactions that make a star what it is.  Behind this has been the development of elaborate mathematics that has made it possible.  There’s so much knowledge we’ve accumulated over those several thousand years.  All in all, we’re pretty damn astute about our knowledge of the universe and our place in it.  We can be proud of that.

Yet, for all our sophistication and knowledge, we’ve never sent humans out into the void of space any farther than the moon.  We’ve sent a couple of spacecraft to the edge of our solar system, but those are piddly jumps compared to the size of the universe or even the galaxy.  Traveling the galaxy is a hell of a lot harder than looking at it.  That’s why science fiction writers have to develop complex, intricate, and ultimately a little naïve spaceships to get their characters around, because there’s no real way to do it.  Light travels at the speed of light; we travel at the speed of rocket ships.  And the difference is telling.

All this suggests that if there are highly intelligent and sophisticated life forms out there capable of traveling the galaxy, or even from one galaxy to another(!), they would have to have knowledge and space drives so far beyond us they would be impossible for us to conceive.  Perhaps harnessing a force we can only guess at.  (Read more science fiction for a few good guesses.)  Pardon the pun, but even in our sophistication, we’ve got a long way to go.