Every living thing has its own ending. We all have to eventually face death. The bigger question is whether the end of the world will come BEFORE or AFTER we die. So let's take good care of the planet, so that it will be around for future generations to enjoy. (Put away those nuclear weapons!)

Yup. In approximately five billion years or so, when Sol runs out of hydrogen in its core, it will start to fuse helium instead, and it will rapidly run out of elements to fuse until it reaches iron. As part of this chain reaction, it will drastically swell in size, easily engulfing the four inner planets of our solar system. Earth will be consumed in a ball of flaming gas and plasma. Of course, by this time the oceans will have entirely evaporated and most lifeforms will be extinct, including humans (unless we manage to somehow become a spacefaring species), so it's a moot point. The real problem is how, if humanity is to endure billion-year epochs, our descendents can avoid the heat death and collapse of the entire universe. THAT will be FAR harder to deal with than the destruction of Earth. But I'll leave the problem to them if they make it that far. Unless, of course, we develop a feasible avenue to immortality within my lifetime, at which point I'll see if I can wait it out with them without becoming bored/insane and committing suicide as a result.

The recently measured mass of the Higgs particle, ~125 GeV, along with the measured mass of the top quark indicates that our universe seems to be metastable: it could potentially collapse into a lower-energy vacuum state at any time, any location, creating a bubble expanding at the speed of light and this vacuum bubble will destroy the existence of our universe. While our "metastable" universe may last for billions of years, it will eventually collapse into a more stable state. All life will quickly and painlessly be destroyed! :D

There were lot of theories about how the world will end. Some of these theories were based on the Biblical prophecy (Revelation) and scientific calculations (projection of objects in the solar system and in the vastness of the outer space, and the age of our planet). One very interesting presentation is the one I watched on Discovery Channel (Stephen Hawking Grand Design). There was an old saying that goes like this "Everything has a beginning and has an end." But as for me, the end of the world depends on every situation that we encounter. A lyric in a song goes "Don't they know, it's the end of the world. It ended when I lost your love." If you're deeply heart broken, it' feels like the world has ended. When you fail an exam, it's like doomsday, too. But we as individuals, create our own world based on our thoughts, speech and actions. We can make our life better or worse. Well, it's all up to the decisions we make and the choices we take. Life is full of struggles and time is running fast. I do believe that one day the world will end. We may not all witness it. In my own point of view, our world ends at the moment we take our last breath. Because it just stops there.

I feel fine. www.youtube.com/watch?v=Z0GFRcFm-aY