There are two questions that every human must ask themselves in their lifetime. Where did we come from, and are we alone in the universe?
In many ways, we’re closer to answering those questions than ever. Recently, it was reported that there is as many as 40 billion Earth-like planets — just in our Milky Way galaxy.
USA Today led its story with these words: “We are not alone.”
I like to think I’m smart. I like to think I’m open-minded. But when I read the statistics I can hardly comprehend it. I can barely comprehend the magnitude of 40 billion pennies, let alone 40 billion planets — entire worlds — out there.
The nearest earth-like planet may be just 12 light years from our reach. That’s 72 trillion miles. Now imagine the closest of those 40 billion — our closest chance of an alien-like world filled with wonder — and it’s so far away that from your back yard as you looked up the starry sky, you’d have to travel for nearly 240 consecutive years just to reach that closest planet (assuming travel at 5 percent the speed of light).
And then there’s 40 billion more Earth-like planets beyond that incomprehensible distance.
Like I said, I can barely wrap my brain around it.
And it gets bigger. That’s just in one galaxy.
How many galaxies are out there beyond just the one we live in? Let Ethan Siegel, a theoretical astrophysicist who specializes in cosmology, answer that question:
One of the bravest things that was ever done with the Hubble Space Telescope was to find a patch of sky with absolutely nothing in it—no bright stars, no nebulae, and no known galaxies—and observe it. Not just for a few minutes, or an hour, or even for a day. But orbit-after-orbit, for a huge amount of time, staring off into the nothingness of empty space, recording image after image of pure darkness.
… the area of the XDF (the Extreme Deep Field they looked at) is just a tiny, tiny fraction of the full Moon.
See that tiny sliver of space the telescope looked at? That tiny sliver of nothingness they decided to stare out at for a decade to see what they’d find. It’s fucking amazing. Let Seigel explain:
What you’re seeing—in practically every point or smear of light—is an individual galaxy. The result gave us the information that a very large number of galaxies exist in a minuscule region of the sky.
Every dot of light is an entire distant galaxy within a square space many times smaller than the moon. What that means is there’s “176 billion galaxies, at least, in the Universe” and could be as many as a trillion.
Who knows what each of those dots hold?
But let’s get back to the dot we live in, the Milky Way Galaxy. Upon reading this news, I found a similar thread in some of the comments.
Who cares, some would say. It’s so far away that even if there’s life, even if it was intelligent life, no one will ever get there. We will never meet aliens.
Last week, as I followed the news at NASA and the Mars One Project, I sent out this tweet:
— Jeff Peters (@JeffRyanPeters) November 10, 2013
Why? someone replied. It’s just a tweet.
They miss the point. I don’t think they spent enough time lying outside in the dark, looking up at the sky and just thinking what was out there.
It’s amazing how the world has come together so quickly the past decade. Children who are born now will never know what it’s like to not live so isolated, so separate.
They can tweet with someone on the other side of the world. They can open up an app and have a conversation with them. Even if they don’t share language, they can read about each other’s lives and culture and hopes and dreams with just the click of the “translate” button. We’re so accustomed to the technology that they’ll eventually chat with people who are living on Mars and not even bat an eye.
It’s just a tweet, they’ll say. You’re so silly, Grandpa.
But when we look at the stars, we know, truly know, that something is out there. We will never meet. We’ll never see each other, but that isn’t the point.
Just knowing is wonder enough.