The Big Bang Theory
Do you actually know what the big bang theory is all about? I will explain
It all starts about 14 billion years ago, when there was nothing, but suddenly something strange happened. Our universe was created, but how? None of the things that exist today were there. Not even space. Then you might ask how in the world our universe was created if there was nothing. Well, we still don’t really know, but the theory is that it all started with a tiny dot. This dot had so much energy in it that it could create the whole universe. With all the millions of stars, galaxies, and planets we see today.
The dot then chose to explode and create the universe. This explosion is called the Big Bang. In that split second, space and time started, but there was a problem. There couldn’t really be anything in the universe, because the temperature was about 10 billion degrees (yea, very hot).
After 375,000 years, the universe had cooled down. Then came two elements, the two lightest — hydrogen, and helium. Now atoms are here too, which can create mass/things.
The new universe, was completely dark because there were no stars or night lights, but apparently, there was a lot of energy. That’s why the universe chose to make hydrogen. After a while, the new hydrogen atoms formed together into clumps, very tight clumps. When these clumps got huge, they became what we call today stars.
That was the end of the dark ages and the beginning of light, but it took us 260 million years. It’s not over yet, there are no planets or any life in the Universe (yet). The Universe had done its job, now it was up to the stars to step in and make a contribution. Back then, there were no elements heavy enough to make “earth”, so there were no planets (there was only hydrogen and helium).
Inside the core of stars, it’s 16 million degrees (like a very hot summer day). In fact, it’s so hot that the hydrogen atoms melt together and become helium and then the helium atoms melt together, and so on and so forth. At some point, the core of a star gets so heavy that the star collapses in on itself and simply explodes from all that energy. it’s called a supernova.
Then when the stars exploded all these elements that were in the core came out into the universe (I like to call it stardust because it sounds fancy), but how did this stardust become earth? Well, it’s pretty complicated, but these elements came together and became bigger and bigger clumps. You might ask how this stardust attracts each other, an American astronaut called Donald Pettit found out. He was an astronaut who liked to do experiments in weightlessness, so he took a bag of kitchen salt into space to the International Space Station. There he saw that, with almost no gravitational pull, the tiny grains clumped together to answer one of the biggest questions about the creation of the Earth.
So when this clump was about 1km across, its gravity started to turn on and so it attracted even more, but it didn’t happen that quickly. It took 30 million years for the clump to be the size the Earth is today.
But the Earth wasn’t quite ready for habitation. I can say this much, it was 2000 degrees celsius hot and it was extremely radioactive from all the unstable atoms. The earth wasn’t hard, it was more liquid. A big lava ball. While the earth was liquid, all the heavy elements sank down through the lava and became the earth’s core.
After 1 million years the Earth cooled down, but of course only the crust, the core is still liquid. There was still quite a lot of activity on the earth. eg. volcanoes and lava flows (but as you can see when you look out of the window, it ended pretty peacefully). So what about all the water, it couldn’t just come out of nowhere. It came with meteors from outer space. Many of the meteors in outer space are huge chunks of ice. In fact, some bathtubs full of water still come every day. It’s pretty strange to think that every time you take a drink of water, it’s coming from outer space.
Now we know where the Sun and Earth come from. There’s still a lot, humanity doesn’t know and a lot this medium article doesn’t say, but all in all, I hope I’ve given you a better understanding of The Big Bang Theory and of why we all are made out of stardust that’s billions of years old.
Credits: NASA, Remy Hellequin, and Aaron Thomas
