Big Bang
No one knows how the universe first begun. Scientists believe that the most possible theory is the "Big Bang" theory.
About 13.7 billion years ago, all the matter in the universe was packed into one dense point called a singularity. No one is sure why, it began to expand. An event that filled all of space with all the particles we know today. All particles moved of the embryonic universe rushed away from each other. That marked the starting point of time. The universe began to cool 3 minutes after the Big Bang. From 100 million trillion trillion degrees Kelvin to 10 billion Kelvin. (18 Billion F)
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It has been a long journey since the Big Bang to us, humans. We are the most intelligent creatures on the only planet known to be life in the vast universe.
- 1 Second after the Big Bang: Gravity Forms
- Minutes after the Big Bang: The universe is made up of 75 percent Hydrogen and 25 percent Helium.
- 200 Million Years after the Big Bang: The first stars are formed.
- 1 Billion Years after the Big Bang: The milky way, our galaxy begins to form.
- 10 Billion Years after the Big Bang: The sun emerges.
- 13.7 Billion Years after the Big Bang: Humans are born.
How long have you been living? It seems like a long time doesn't it? Will imagine 13.7 Billion Years since the start of time till the present.
Stars
Every star, anywhere, you see in the night sky is a superheated ball of gas. Our sun is a star that we are very close to. If you are further away , the sun will just look like another light in the bright sky.
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Without the sun, the Earth would not survive.
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Have you ever looked up into the night sky and wondered just how many stars there are in space?
Just like the sun, there are about 100 Thousand Million stars in our galaxy alone! There are Millions up Millions of other Galaxies our there! You do the math.
The estimate is three planets per star. So times your answer by 3.
Just think about it, so many stars, so many planets, such a vast universe. Yet, we have not found any source of life other then us, (the earth).
Why us?
End of Earth?
There is no turning back, our planet is growing older and older by the second. Soon it will die out. But, will it die of old age or will it die due to its inhabitants?
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The Earth is home to all the existing life known up to the present day. What if it was to be destroyed? Does that spell the end of life?
Here are many ways the Earth can be destroyed.
Total existence failure: Do nothing, the Earth, or even the universe has a chance of exploding for no reason. Everything will start to not exist.
Sucked into a giant black hole: A black hole could form very close to us and suck up the Earth.
Humans: This is the main worry for us. We believe that eventually we will be too smart and do something stupid which will end the world. It might be a new invention, a new idea, a new experiment. We might try to do something that we will not know ends the world. It might be global warming.
Conclusion
What ever the cause is, there is no way to stop it. The whole universe will eventually end some day, but that is for another generation. For us, we will end before the universe does. And we might never find out the secrets of the Universe. If there is life in space, Why ONLY US?
How is it possible that there is no life out there, when there are over billions and billions of stars? This question might remain a mystery forever: Is there life out there?
