There is a widespread belief that it is very possible alien life forms, if they exist, have the capability to travel to the Earth, and may have done so in the past or may even be doing it now. This is not a reasonable belief. First, it assumes there is intelligent life out there in the Universe. (If you don't believe that then none of this really applies to you does it?) I like this 1st assumption, I believe we will eventually discover that life, or the seed of it, is everywhere, and if it finds a place it will grow. In my personal view of the Universe, the Earth is just a crack in the sidewalk. Second, it assumes that these aliens have some way of traveling great distances across space within a reasonable time. It's this second assumption that is seriously flawed. Third, it assumes that the UFO's we see are from somewhere else. This is also folly. There is no evidence to suggest that any of the unidentified objects we have seen are from anywhere other than here. It's not like we saw them coming as they passed Jupiter and Mars, then the moon, then entered Earth's atmosphere.
Alright, first let's start with a famous equation, I like to think of it as garbage, but the media keeps throwing it out there. The Drake equation, I am not going to go into detail, but it goes something like this. If you have "X" number of Stars and "Y" percentage of those stars have planets capable of supporting life, then "B" percentage of those planets have life and of those, "M" have intelligent life. ( I made up my own letters but this is the basic idea)
This "equation" is full of made up guesses, garbage in garbage out. There is no real data here. But, for the purpose of this discussion we are going to go ahead and assume that there is intelligent life out there. Matter of fact we are going to assume that there is intelligent life ALL OVER the Universe, every galaxy, has self-aware creatures, and in every galaxy there are one hundred advanced civilizations.(Not the little freak galaxies that have been split in half or are tiny weird variations, just typical spiral galaxies, ok?) Crazy right? This is WAAAAAY more than the Drake equation would ever allow. So just so we are clear, the basis of our little thought experiment is that there are 100 other civilizations just like us in our own galaxy, and 100 in every other spiral galaxy out there.
It’s too far, we’ll never make it.
OK, let's start with our nearest spiral neighbor, Andromeda. The reason we are going to start there is because if "they" can't get here from there, it's pointless to assume they might get here from any other galaxy, there are about 30 galaxies within 4 million light years, but only a few are regular spirals, so we'll just use Andromeda as a reference point. The rough estimate of the distance to our closest spiral galaxy neighbor is 2.5 Million Light Years, so let’s be nice to our aliens and say 2 million.
OK, we now have 100 civilizations and a distance of 2 million light years. Now let's make them all smart, really smart, and give them a desire to get out there and see the neighborhood. One of them starts playing with fusion and they get the power of a medium sized star in a shoebox, I think we can all agree with that kind of power and technology they are ready to go. Then, for whatever reason, they head straight for us, not stopping to look at this or that, no detours, no study of anything along the way, shoulda went to the bathroom before we left, we ain’t stopin till we get there!
Speed of light - The whole house of cards comes crashing down.
Our little aliens have the power of an entire star at their disposal, but that is not even close to being enough to propel them the speed of light. Much of our current theories and laws of Physics and Astronomy, our understanding of how the Universe works, is based on the speed of light, ergo, the most popular mathematical equation in the world...E=Mc2, Energy equals the speed of light squared. This foundation, this revolution in physics, states that nothing with mass can go the speed of light, NOTHING...EVER...PERIOD. This is checkmate for our little visitors. This means that even if they could go very very close to the speed of light, it would still take 2 million years to get here. I think we can rule out Andromeda as a source of alien visitation.
Now that we have ruled out visitors from another galaxy, what about our own? Well alright then!
We have 100 smart aliens right here in our own galaxy, with the desire to get out and tour the countryside, great!
So here is the 1st problem, they are still, really, really, really far away. Our galaxy is around 100,000 light years across. Traveling as fast as the speed of light still takes 100,000 years to get from one side of the galaxy to the other, and that’s going right through the center, which is probably not a good idea. So if our little friends happen to live on the other side of the galaxy, it will be 200,000 years after departure before they can tell their friends back home that they have found something. You see, it’s not just matter that can’t travel faster than light; it is information of any kind. (There is a weird special circumstance, due to the expansion of the Universe, that some really distant galaxies are actually receding from us faster than light, and due to that, no information can ever be known about them, we can’t see them anymore.) Well, good thing we have decided that there are 100 of these guys out there! We spread them evenly about the galaxy, staying away from the center, (because it’s too busy in the center, life would most likely have a chance to form and flourish out along the arms) and for simplicity we will say there is a band of life making a perfect circle around the center of the galaxy, the same distance from the center as us and the same distance away from each other. We are about 27,000 light years from the center, so that gives us a circle of roughly 170,000 light years, divided by 100 and you get 1,700 light years.
1,700 light years from us to our theoretical best case scenario neighbor, that’s pretty close, right? Well, it’s much better than 2 million, but it still is too far, even at the speed of light. Let me put it to you this way, if they left around the fall of the Roman Empire, they would just be arriving now.
The only tiny (and I mean tiny) glimmer of hope for the odds, is the fact that there are something like 50 stars within 20 light years of earth. 20 light years is doable, they might even be able to pick up “Friends”. Alas the odds are overwhelmingly against a neighbor this close, more on this later.
What do you mean “We’re out of toilet paper”???
Up to now we have only discussed the distances and speed, but to make the trip you have to eat and poop. Even if they have suspended animation, they have to have all the stuff they need when they get here. The logistics of galactic travel are mind boggling, and they will be on their own when they get here, no calling for help or spare parts, not to mention the physical effects of low gravity for extended periods, radiation, computer glitches, (C’mon, you KNOW they would have computers…), micro-meteors, and unexpected stuff in general. Try cramming all that gear into a flying saucer…
Sorry babe, it’s just not our time
Well, here we are, 14 billion years after the big bang, talking and flying, going to the moon and being modern hominids. We’ve come a long way in the last 100,000 years.
100,000 years… seems like a long time doesn’t it? It’s not; it’s a drop in the bucket. In the timeline of the Earth and out star, a million years is not even that long, and many people would agree there is a strong possibility humans won’t even be around in a million years. We are but a fleeting moment in the grand timeline of the galaxy, and therein lies another huge problem. We are not just separated from our potential neighbors by distance, but by time. It is very unlikely that the 100 intelligent beings we have so graciously given thought to, will ever develop around the same time. It is far more likely that they will develop at minimum, a million years apart, so that, even if they traveled the galaxy and came here, we were not here, or won’t be here when they arrive. One intelligent life form developing at the right time and distance from another is like the desert wind blowing together a perfect replica of a telescope, sure there is nothing in physics that prevents it, but it is so unlikely you may as well call it impossible.
Don’t get me wrong, I want to believe, I just can’t.
