When we look up into the night sky filled with a myriad of stars, we are not only looking at the stars but also through a lot of space, trillions of miles of it. Exactly what is that space up above us? It is a difficult question to answer.
Common sense tells us it is just empty space, a void of oblivion, the ultimate nothing burger. Not so fast. Astronomers and cosmologists are now thinking that space is something. What that might be they do not really know. Not a something like margarine that you spread on a piece of toast, but some kind of a something.
Albert Einstein taught us to think of space and time as one thing together. We often call it the fabric of space and time. Now the word fabric sounds like something we can relate to. Fabrics are part of our everyday experience. Think of those spandex tights you wear on your daily run. They stretch with you, which makes them so comfortable. What does this have to do with space? It stretches, too.
Can you believe it? Gravity makes space bend and stretch just like a bowling ball tossed onto a trampoline. The heavy ball stretches the fabric of the trampoline. A golf ball would stretch it also but not nearly as much because it does not weigh as much.
So this gives us a clue that space is something if it can stretch. Space also expands, getting bigger and bigger. I admit that’s pretty weird. How can nothing expand? Here is another question. What is it expanding into?
Astronomers will be the first to admit that they are scratching their heads over that one. Look at that coffee cup in your hand. The space between it and your lips is actually getting larger by the second. Thankfully not by very much because it is not that much space. But the space between us and a distant galaxy is a lot of space so it is expanding a lot, which is why the distant cosmos appears to be running away from us like we have bad breath.
Powerful energy
Why is space expanding? Astronomers blame it on “dark energy.” Which is another way of saying that they do not have a clue. It makes up almost 70% of everything that is dwarfing not only our little world but also all the stars and galaxies out there.
That stuff, whatever it is, is powerful. It is estimated that a peanut butter jar of “empty space” contains enough energy to boil off all the oceans in the world in less than a second. If we could figure out a way to harness that power, we could say goodbye to oil, coal and all our other forms of dirty energy.
I will tell you one more weird thing about space, which I think is the weirdest of all. Fast forward way into the deep future. Our sun has exploded, the earth is just a charred cinder. All the stars have died and there is no more hydrogen gas left in the universe to make new ones. Everything has been sucked into black holes and they have all evaporated. Can you believe it? Black holes evaporate into nothing? The late great physicist Steven Hawking figured out that one. Quadrillions of years into the future all that will be left of the universe is space expanding, always expanding, into eternity.
OK, let’s come back down to earth. What is out there to look at? Low in the southwest, Venus is brightly gleaming in the twilight glow. If you have a small telescope, check out the little crescent it has become. It will get even thinner before it disappears into the sunset glow in December. Much higher and farther east, Jupiter shines almost as brightly. To the right of Jupiter, Saturn, not nearly as bright, glows with a yellowish hue. That small telescope will show you four of Jupiter’s 67 moons and of course the rings of Saturn.
Do not worry too much about all that space out there. Hopefully it is just doing its thing, whatever that is, and not paying any attention to us.
