If you could get in your car and drive to Proxima Centauri, which at four light-years away is the closest star to Earth, it would take you approximately 38,262,857 years to get there, if you drove 70 mph.
38,262,857 years? I get bored during the 1-1/2 hour car ride to my parents’ house in Guthrie. And Proxima Centauri is the closest star to Earth.
Now try this:
If the Sun were the size of a basketball, the Earth would be only 2.3 millimeters or so in diameter. On that scale, Proxima Centauri would be another basketball 4,726 miles away, which is almost the driving distance from Anchorage, Alaska to Miami, Florida!
And remember, that’s the closest star!
There are approximately 400,000,000,000 stars in our galaxy, the Milky Way. The Milky Way is around 527,912,640,000,000,000 miles in diameter. I could do another analogy, but you probably realize by now that it’s bigger than we as human beings can imagine. It’s fucking huge. We could never travel to the center of it. It would take forever just to get to our next-door-neighbor star unless we had some kind of breakthrough in our understanding of physics.
You should also know that the Milky Way is just an average galaxy in a universe full of galaxies. In fact, there are an estimated 125 billion galaxies in the universe. How do we even know this, since everything is so far away? By using telescopes, of course, especially the Hubble Space Telescope, which you may know is a satellite in orbit around the Earth.
Hubble once took a picture called the Ultra Deep Field, which is a picture of many galaxies. The way it did this was by looking in a specific direction that allowed it to look outside our galaxy without nearby stars getting in the way. Like, if you were in a crowded nightclub, and you were trying to check out some hot girl at the bar, you would have to wait until there was a break in the crowd, a clear line through which you could see her. Right? Astronomers found a line like this that they could use to see outside our galaxy of stars. And this is what they saw:
That’s a lot of galaxies, right? 10,000 or so in this photo. But how big is the photo? How big a picture is it? Well, you know how big the moon is, right? Bigger than anything else in the night sky, but still just a tiny patch. This picture is fifty times smaller than the amount of sky the moon covers. It’s a tiny, tiny patch.
10,000 galaxies in that tiny patch. And the whole universe is like this patch.
There are more galaxies and more stars and more planets in our universe than you or me or anyone else can get their mind around. There are undoubtedly millions or even billions of planets that have life on them, that have creatures walking and talking and swimming and flying. There are surely civilizations that rose and fell before humans carved their first knife. Before the Earth even existed.
Our planet is just a tiny speck of dust in a cavernous, empty universe. The amount of good fortune required for our planet to sustain any life at all is inconceivable, let alone intelligent life like humans. All of us are lucky to even be here, trying to make sense of this world. It’s easy to become overwhelmed sometimes–by our jobs, our relationships, by our own mortality–but at least we’ve been given the chance, right? At least we’re that lucky, right?
I feel lucky.
If you have any questions or comments, write me.