If you live on this planet you love sun and are a big fan of its work. It provides earth with just the right temperature to sustain life. The sun hasn’t been so gentle with us all the time and it definitely wont stay the same in the future. I know I know, calm down.
Currently our 4.5 billion years old sun is just like a middle aged man just past his teenage. Our Sun will spend its next 7.7 billion years growing bigger, hotter, brighter, cooler, changing its color, and finally into a white dwarf all while trying its best to destroy the earth. Sure the earth as a planet will survive sun’s might but us and everything else living on this earth, not so much.
Our sun essentially eats hydrogen for breakfast, lunch and dinner. It fuses two hydrogen atoms to form helium atom and also releasing a heck of a lot of energy. As the time passes our sun will exhaust all of its hydrogen. Then the helium and other heavier elements in its core start fusion reactions of their own. As a result more and more heavier elements like lithium,beryllium and carbon are formed in its core. Due to this, the pressure in its core starts to build up and the sun starts to expand into a red giant. A red giant is basically a bigger and badder version of our sun which will have a radius twice of that of the distance between the earth and the present sun. So basically this is the end of existence for our earth.
Then our sun starts to loose its outer layers and starts to compress and becomes a white dwarf. This is basically the end of our sun. Our sun emits all of its remaining energy and then fades away into a black dwarf floating endlessly in space.
So, don’t pack your bags yet and sign off your bosses you still have more than 7 billion years to live on this earth, if we manage to live for such a long time.