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How is a white dwarf? | Astronomy
How is a white dwarf? Even 10% of stars in our galaxy are white dwarfs, and our sun will be at the end of her lifes journey also turned into one
As many as 10% of stars in our galaxy are white dwarfs, and our sun will be at the end of her lifes journey also turned into one. White dwarf is a very dangerous form of stars. It arises from an ordinary star when it comes to separating the outer layers of the core . Until this phenomenon occurs in the later development process when the star is in the red giant phase. then blows the outer layers that can be seen as a planetary nebula, leaving only the core of the former stars. It then gives birth to a white dwarf. separation of the stars is due to exhaustion of stocks thermonuclear fuel from the center of the star. remaining dead center begins to implode into itself. gravitational force that is directed toward the center of the star is no longer balanced pressure of hot gas that pushes the upper layers of the star where compressed to very small dimensions.
The white dwarf has a mass larger minor radius. degenerated gas of which are sustavljene these stars - and that is not on Earth - has put pressure on the star that is collected. When density rises to a certain value, will establish the equilibrium pressure and the mass of the white dwarf. Because of the degenerate gas, the white dwarf is so compressed that the electrons in it can no longer approach each other. For this reason, the collapse of the interruption. next step would be to take the same two electron energy state, but it is not possible due to the refusal of forces and the collapse stops. Of course, there is an upper limit at which the mass can reach this balance, and it amounts to about 1.4 solar masses. remaining part of the former red giant has a very high surface temperature that is gradually cooled. temperature white dwarf at the time of occurrence of at least 20 million Kelvin. He cooled after 1.5 billion years and during that time loses its shine and becomes darker. So it is difficult to see when they are in an advanced stage of development. However, the star called 40 Eridani B is the most visible white dwarf star in our sky, and Sirius B , for which you have probably heard, the brightest and closest to us white dwarf, as big as Earth. It is interesting also that he, therefore, something as big as the Earth has a density of 90.000 times higher than the sun and 125,000 times greater than water. All low-mass stars like our Sun will end the life cycle as white dwarfs.