Life cycle of the Sun

The millions and billions of stars in our cosmos are studied examining the visible light and other radiation they are emitting.  The radiation is captured by telescopes on Earth and in near space and scientists can determine from the photos at which point of its life cycle a star is from its birth, aging, and its death.

The fundamental research helps us to understand the life cycle of our own star, the Sun, Helios, on which the existence of planet Earth and everything on it depends.

Life cycle of the Sun (wikipedia)

Today it is generally considered that the Universe is about 13.75 gigayears old. Sun was created about 4.5 gigayears ago together with its planetary system so according to our present knowledge it is about one third of the age of the entire Universe.

The life of a midsized star like our Sun has been carefully studied. Astrophysicists, astrochemists, nuclear scientists and other smart people have calculated in detail what will happen and why according to the known Laws of Nature.

Today it shines on the sky as a 4.5 gigayears old star and is doing well what a Sun is supposed to do.

But after another 4.5 gigayears when Sun reaches the venerable age of 9 the nuclear fuel burning inside it begins to show signs of running out.

Consequently many things will happen but in a nutshell, the warming Sun will start to grow so that at 10 gigayears it is a Red Giant. So big that it has devoured planet Earth.

The fun of being all swollen up will not last very long in cosmic time. After some rather massive and sad events the Red Giant will be smoked into a hazy planetary nebula where the bright Sun once was shining in one of the spiral hands of Milkyway.

What remains of our Sun at the old age of 12 is just a lifeless White dwarf that will be getting cooler and cooler in the dark space. Sun will have 0.6 of its current solar mass but all this is compressed into the volume of the Earth. Not a big thing in the Universe rather like a grain of sand in the beach.

Small, medium sized and large stars have different life cycles and all are studied by men on this planet. According to latest estimates humans and their nearest ancestors have existed on Earth about five to seven million years but only recently, some moments ago, humans have started to grasp where they are in the Universe and what is going to be the faith of Sun in the not too near future.