As we all know, now, the universe is enormously vast – vast beyond human comprehension. However,it is only recently that we have had the tools required to have a true notion of the huge expanse of space our world inhabits… and how tiny our little speck of air and soil and water truly is. Not to mention, how precious it is. It seems impossible, really, to consider the entirety of the cosmos, and still, somehow, remain convinced of any sort of special place in the universe, for ourselves. It just seems like a ridiculous proposition. It seems like whishful thinking, at its most extreme, and remarkably egotistical. Who do we think we are? On the scale of the universe, or even our miniscule solar system, we aren't even gnats. Our whole planet amounts to no more that a microbe on a grain of sand on the cosmological scale! Our Earth is dwarfed by the Sun, and the Sun is incredibly insignicant and tiny, itself, lost in the vastness of the universe.
In the dimension of time, if a person lives to be a hundred years old, that's about as long as a person can live, give or take. That's the best we can hope for as human beings. So, when we compare that to the age of the Earth, or the age of the visible universe, it quickly becomes apparent that our lives are very, very short… fleeting, even. The Earth is supposed to be almost four and a half billion years old, for example. That's a very long time for us, of course. But, how long, precisely, is a "very long time for us"? Well, if we look at our lives as a fraction of the Earth's life, we'll find a number:
We would need almost 45 million lifetimes, of a hundred years each, to be as old as the Earth!
We could get through all of human history with less than 100 of those 100-year lives, though. Less than 50 lifetimes will take us back to the invention of agriculture. 35 will take us back, more or less, to the development of writing. On the scale of Earth's geology, our lives are but a twinkling of an eye. And on the scale of the universe, which is almost 14 billion years old, it would take us almost 140 million lifetimes to stretch the distance. So, you see, our lives, while they seem long, tedious and arduous, are really quite fleeting and fragile.
In the three dimenions of space, though, we really begin to understand where we fit into things, on a larger scale. It is theorized that all of the vastness of the universe we know, today, was once contained in what is called a "singularity". To get things started in the cosmos, this immeasurably small point of matter and energy exploded, in what we know as The Big Bang. Ever since that time, 14 billion years ago, the universe has been expanding, faster and faster. Everything is always moving, farther and farther, from everything else. Like beads on a rubber band, when stretched apart, the beads grow father from each other, in both directions, as the rubber band is stretched. That's a reasonable analogy which makes it easy to enderstand. But, this happens in all three dimensions, not just along a single line, as on a length of rubber. This expansion of the universe, and the speed with which it is expanding, continues to increase, even now.
In essence, we live within a 14 billion year old explosion which is still expanding.
How's that, for perspective?
In our universe, there are countless billions of galaxies, each with countless billions of stars. There are more galaxies in the universe than there are grains of sand on all the beaches in the world. Our star is but one unremarkable star, on the edge of a galaxy composed of billions of stars, in a universe with billions of visible galaxies. If all that isn't enough to make us feel puny, here's one more thing: there are almost seven billion people on the planet right now! So, we can factor that last calculation in, 1:7,000,000,000, on the tail of the other ratios here, and see we are really quite ephemeral beings. Our lives are so quick, and so anonymous, as to almost seem not to matter, at all.
Our lives do matter, of course…
Perhaps, though, not nearly as much as most of us tend to believe.
All these things are enough to drive the point home and, also, are enough to blow our minds. Especially, if we ponder the facts at hand with anything like the sort of attention they're due. But, the most amazing thing of all is that, even though there are all these countless galaxies, stars and planets – all this stuff we can see... most of the universe is invisible to us! That's right, most of the matter which exists in our universe is undetectable to us. We can't see it or interact with it in any way. We only know it's there by the effect it's having on the matter which we can observe. In case that idea, itself, isn't spooky or weird enough, we call it "dark matter", just to give it a name. It has a cousin, too, called "dark energy". We haven't even spoken of the radiation, and other crazy stuff, out there, which human beings can't possibly survive. This makes our little life-sustaining bubble a very lonely place in the cold, dalk, hostile universe. It also makes it clear just how ridiculous it is, in our feeble state, to have any sort of ego or feeling of power. Who are we kidding?