“The Earth reminded us of a Christmas tree ornament hanging in the blackness of space. As we got farther and farther away it diminished in size. Finally it shrank to the size of a marble, the most beautiful marble you can imagine.” -James Irwin
With everything that goes on in this world, from our daily lives to concerns around the globe, it’s easy to forget just how vast the Universe is, and how small we all really are. You had so much fun playing with the Interactive Scale of the Universe tool a couple of weeks ago that I had to just give you a few things to ponder. We think of the Earth, our entire world, as a pretty large place. But let’s put this in perspective.
The entirety of our planet, immense in both size and mass, is tiny compared to the Sun. The Sun is 109 times larger in diameter, over 300,000 times more massive, and has sunspots bigger than our planet.
But in the context of the Milky Way, our Sun — and even the entire Solar System — pales in comparison.
Our Sun, 1.4 million kilometers in diameter, has a Solar System that extends out beyond Pluto, to a distance of about 140 billion kilometers. That’s the distance to Sedna at its farthest point from the Sun, the most distant Solar System object ever discovered. But even that great distance is nothing when placed into the context of our galaxy.
Because the distance to Sedna is just 1.5% of one light year, meaning it takes light around five days to go from the Sun to Sedna. But our galaxy is 100,000 light years across, or about ten million times the diameter of our Solar System. And it ought to be. Our galaxy alone contains hundreds of billions of stars, most of which have solar systems not unlike our own.
But compared to the rest of what’s out there, our galaxy is terribly insignificant.
Although “only” about 250,000 galaxies are shown in the above image, the entire Universe is estimated to have at least hundreds of billions of galaxies, spread out over a spherical region about a million times larger in diameter than our galaxy is. In other words, you and everything you know resides on a tiny, wet rock nearly a million times less massive than the star that powers it, in a solar system one ten-millionth the diameter of our galaxy, which contains at least hundreds of billions of stars not so different from ours, in a Universe filled with hundreds of billions of galaxies, and maybe perhaps more.
You. Are. Tiny.
It also inspired me to dig up this old (2008) video, that helps put into perspective just how big the Universe is. Sometimes, pictures can’t do the same justice that a well-put-together video visualization can. And the Universe? It’s really, really, really big!
Remember how big this Universe is, and how tiny we all are. But despite all of this, we all get to be a part of it, here, on the most beautiful marble you can imagine.