Alien life

Perhaps as a matter of coincidence, I had been reading and watching a lot of shows on space recently - most notably getting caught up on the COSMOS series by Carl Sagan - when the new show on Discovery Channel launched (Into the Universe with Stephen Hawking). And speaking of coincidences - the subject of life on other planets is always at the forefront of these shows.

It has got to be the single biggest question anyone ever ponders about the universe. Are we alone? And obviously you can't spit without hitting someone with an opinion on this (and around here that opinion is largely driven by the person's religion). And since I'm generally no different, I'd like to capture a few of my thoughts - albeit without the religious connotations (mostly).

So it seems to be generally accepted that life on earth is the product of a series of "accidents". That is to say that unique occurrences transpired in just the right manner to create molecules capable of creating copies of themselves at which point evolution took hold - and the rest is history.

So the first question then becomes - what is the likelihood of these occurrences taking place in other parts of the universe? Well admittedly it would have to be pretty rare - but considering the size of the universe, the odds certainly increase. After all, our Sun is but one of trillions and trillions of stars in the known universe. So - accident or not, if the laws of physics are such that under the right circumstances, life can occur - then I think it is highly likely that it has happened elsewhere. But it is the next question which concerns me more.

Is there "intelligent" life and will we ever discover it? (I'll refrain from the judgement of "intelligent" life on our own planet.) Provided life exists at all on other planets - the question of intelligent life really only depends on "time". If we accept that evolution would have to follow the same principles on other planets - it is reasonable to believe that intelligent life would eventually arise given enough time. In the case of the earth it took about 2 billion years. But unfortunately - there are some extenuating circumstances to consider, namely that all discernible life on earth has been destroyed approximately 4 times in its history (this includes the extinction of the dinosaurs). Now obviously all life wasn't destroyed - but one would certainly have to expect that this greatly impacted the rate at which we, as a species, evolved. Had the dinosaurs not been wiped out 64 million years ago, there might still be no humans on our planet - yet. So if other planets did not have similar circumstances - intelligent life may have evolved much sooner. And of course, if other planets did have similar circumstances - intelligent life might still have been thwarted. But for the sake of argument we will suppose that it takes roughly 4 billion years (rough estimate of the age of Earth) to produce discernible "intelligent" life.

The universe was roughly 10 billion years old before the Earth even began to form from the remains of a second generation star which had exploded. It is reasonable to believe that a life sustaining planet would have been much less likely to form from younger stars simply due to the lack of heavy materials produced by successive stars. But that said, the life of a star is not a perfectly determinable number - meaning every star does not have a known life span; they can vary by millions of years. So, again, it is reasonable to expect there were planets capable of sustaining life being formed millions of years before our own. And it goes without saying that similar planets are just beginning to form in other parts of the universe. So being conservative - if we look at the life span of the human species over the last 5 billion years - we are barely even a blink of an eye. And unless we can find a way to prevent both man made catastrophes as well as natural catastrophes - we will never be more than a blink of an eye. No matter how long we manage to live, the earth will one day be subjected to natural forces which render life impossible for our species. Life on any other planet should be no different.

So...Can we expect to ever find "intelligent" life on another planet? My opinion is no. As long as we (and any other planetary race) is confined to their home planet, the likelihood of discovering intelligent life on another planet is simply astronomical (pun intended). However, if we and other civilizations live long enough to manage to send sustainable life beyond our home planet and are able to travel at near light speed - then I think the odds could get much better. But I think the greater likelihood is that we will discover a planet which has either A) little more than single celled microbes or B) a "dead" planet which did once have intelligent life forms (or any type of life for that matter). And the same goes for future races who might stumble upon our planet long after we are dead and gone.

The prospect of finding intelligent beings on other planets is both awesome and frightening. On the one hand, virtually nothing else could unite all humanity like the hatred and distrust of another race entirely. And on the other hand, human history teaches us that the meeting of these 2 races isn't likely to be entirely peaceful. But who knows what the universe has in store for us?

Then again, I could be completely wrong...