What will you take for granted today?

 It's a pretty safe bet that if I didn't mention it, 

you wouldn't give the sun a second thought today...

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How many years are left on sun? Best we can figure is about 5 billion years. Eventually, the fuel of the sun - hydrogen - will run out. When this happens, the sun will begin to die. But don't worry, this should not happen for about 5 billion years. After the hydrogen runs out, there will be a period of 2-3 billion years whereby the sun will go through the phases of star death.

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The Sun is a huge, glowing sphere of hot gas. Most of this gas is hydrogen (about 70%) and helium (about 28%). Carbon, nitrogen and oxygen make up 1.5% and the other 0.5% is made up of small amounts of many other elements such as neon, iron, silicon, magnesium and sulfur.

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The color of the sun is white. The sun emits all colors of the rainbow in approximately equal amounts and we call this combination "white". That is why we can see so many different colors in the natural world under the illumination of sunlight.

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The Sun burst into life around 4.6 billion years ago, which makes it the same age as the Solar System as a whole and around half a billion years older than the Earth. That's because, with a few exceptions, planetary systems such as our own Solar System do generally form at the same time.

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The Sun glows because it is a very big ball of gas, and a process called nuclear fusion is taking place in its core. Nuclear fusion occurs when one proton smashes into another proton so hard that they stick together and release some energy as well.

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