Comparing Stages of the Sun

Red giants: The red giant phase of a star marks the next progression point to star death. after a star is about a few billion years old, the star starts to run out of fuel (or protons) to burn on. the star then begins to cool and contract, but as it contracts, it heats up. causing the remaining protons to be fused into alphas. these alphas become the new source of energy for the star. Now the star is much hotter than before, and the outer parts of the star begin to swell and expand. Which in turn gives the term "giant" for its name. The first half of the name comes from the shade of red the low level of radiation gives off. Red giants are the most common star visibile to the naked eye, but strangely enough are not very common occurences in space.



White dwarf: after the red giant phase, the star continues to run out of fuel to burn on. When it reaches its breaking point, it then sheds all of its outer layer material and makes a planetary nebula. This planetary nebula leaves behind the core of the star, which keeps burning even hotter then before. The star smolders for approximately another billion years more, all the while running out and cooling down. White dwarfs are particularly interesting due to their characteristic way of compression. most objects in space have a special internal fusion that prevents it from collapsing by the gravity surrounding it. But white dwarfs maintain its existence by quantum mechanics. This means that all the elctrons in the dwarf are forced so close together that they have no where else to go within their energy levels. Since only two electrons can be on energy level they are stuck thus keeping the dwarf alive and in a shape.



Black holes: Black holes are the famous ending to a star's life. They are at least ten times larger than the star itself. While the star burns out, it runs out of substance to keep it alive. As the star reaches its collapsing point, it then has reached zero volume. At this zero volume, it has achieved infinite density. Light rays are now bent around the star and are caught in its orbit. The black holes are so dense, that they do not allow light to escape. The were originally discovered not because the scientists could see them, it was because of the effect they have on surrounding areas.

Our own sun is still striving to be the red giant stage, thank goodness we still have about five billion years left of the sun's life. In fact, as we progress in time, the sun is losing weight. As mentioned earlier, it continues to burn energy, and therefore is now lighter. The sun is about ninety-eight percent of our solar system's mass alone and it burns at 11, 000 degrees farenheit! It have a uneven appearance due to the eruptions that occur on its surface. It is about four and a half billion years old. It is predicted that when the sun is ready to progress into a red giant stage, that the sun will swell so large that it will take the Earth with it. Obviously we still have plenty of time before this is a problem, so rest assured!