The End of the Earth, how do you think it will happen? Options

[Frostedflakes616]

There are many theories on how the world will end for us, on how the Earth and us with it will be destroyed.

First Theory:
As you all know of the Big Bang, which is believed to be the start of the universe. Some say that the universe may go back to that little sized pearl and we will be destroyed.

Second Theory:
If you did not learn this in school, the sun is a star. And all stars have life and death. Their death is when they explode becoming a nova/supernova. Which means the sun will have one as well. They say eventually, the sun will end life and explode, destroying the Earth.

These are the two main theories that I know about. What do you think? Do you think the universe will go back into the pearl sized amount of gas? Or will the sun blow us up?

You decide. If you know of another theory, feel free to mention it.

My Opinion:
The first theory in my opinion is highly unlikely. I don't believe the whole universe will shrink back. If anything, the universe will keep expanding forever. I do believe in the second theory, but that will probably not last for another couple million or even billion years. If not that, we'll be destroyed by a meteor or colide with another planet, both seem to be unlikely. So if we don't get destoyed by another planet (by collision) or by a meteor, the sun will blow up on us.

[Gigi]

I can think of a multitude of things that could slowly kill the earth, but these are all theories that could be prevented in the future. There's one theory that is inevitable, and it's related to the sun.

Well, as you all know, the sun is a star. In 7 billion years, it will use up its fuel supply and collapse. But it's important to be familiar with a star's life cycle.

Nebula --> Star --> Red Giant --> Red Dwarf --> White Dwarf --> Supernova --> Neutron Stars --> Black Hole

Our sun is currently at the "star" stage, but in the future it will become a red giant. Red giants swell from 10 to 100 times larger than our sun (or their star stage). Some can even swell up to 1000 times the size of our sun.

So, the sun will begin to expand as it ages, engulfing anything in its path as it gets closer to the earth. As the sun expands, earth's temperature will begin to rise and will eventually become unliveable. Our oceans will evaporate. Carbon dioxide levels will drop, and the process of photosynthesis wouldn't be able to be carried out, and our plants would die. We would die. Our only option then is to move on to another planet where the temperature has, by that time, become more moderate (say, Mars. Jupiter, even), or to perish altogether. Eventually the earth will become victim to the growing mass that is the sun, and any planets we "move" to would be engulfed as well.

So, really, the earth will be destroyed before any sort of explosion from the sun.