Even stars die but they die out in fashion. Some go boom (supernova explosion), some swell up like balloons and some end up as black holes. We have already written about supernova and black holes. Let us to learn 20 interesting Red Giant star facts. Red Giants refer to the ones that swell up like balloons. Let us find out what causes such swelling up and what type of stars end up as Red Giants. In the meantime, if you are interested in reading about Supernova and Black Holes, feel free to follow the following links:
Interesting Red Giant Star Facts: 1-10
1. Stars that are about the size of our very own Sun end up as Red Giants at the end of their lives. As far as the fate of our Sun is concerned, it is not going to die anytime sooner than 5 billion years from now. So, we are pretty much safe unless of course a freak asteroid is sent hurling towards Earth for a catastrophic extinction-level impact before Sun’s life ends.
2. Stars that are 1/3rd to 8 times the size of sun end up as Red Giant Stars. Now stars are usually made up of a gas called hydrogen. At the core of a star, the every two atoms of hydrogen fuse together to form one atom of helium – a heavier gas than hydrogen. This fusion is called nuclear fusion reaction.
3. The problem with stars is simple, they fuse hydrogen into helium at their core (very center) and hence, helium has nowhere to go. After billions of years of fusion reaction, stars accumulate huge quantities of helium at their cores and gradually, hydrogen that made up a star is slowly burned out (we mean fused into helium).
4. Hydrogen is actually the fuel that keeps stars alive. When the hydrogen is gone, the stars have no hydrogen molecules to fuse. This is where the stars come to the end of their lives.
5. During this whole lifespan, i.e. when hydrogen is fused into helium, an external pressure is created because of the fusion reaction. It is this external pressure that keeps stars from collapsing because of the immense gravitation at the core of the stars.
6. With no external pressure left, the stars now succumb to the gravitational pull of their cores. With strong gravity into play, the stars now star contracting in on their own core. So, the stars become tighter and smaller.
7. With the onset of the compression, the stars heat up gradually because more and more mass is getting packed in smaller and smaller space. The gradual buildup of temperature eventually reaches a point where the helium present in the stars can now start fusing together into carbon atoms and oxygen atoms.
8. This helium fusion can start with a sudden and explosive flash or it can start gradually and slowly. Exactly how the helium fusion starts is dependent on the mass of the star.
9. Again, fusion reaction releases energy. This massive amount of energy produced because of helium fusing into carbon is trapped inside and tries to go out. This leads to enormous pressure buildup which in turn starts pushing outwards. This leads the stars to expand.
10. At this expansion phase, the stars begin to swell up. They expand and expand and expand until they grow massive with their diameter ranging between 100 million kilometers to 1 billion kilometers. In other words, they grown in size by about 100 times to 1,000 times their original size.