Low to medium mass Stars will become white dwarfs, where the mass is up to 8 solar masses (8 times the mass of our sun).
There are two types of white dwarf stars;
- low mass stars with a solar mass less than 0.5 will become helium white dwarfs. The temperature of these will not be high enough to fuse helium into carbon.
- low to medium stars with a solar mass between 0.5 and 8 will become Carbon-Oxygen white dwarfs.
Any star larger than 8 solar masses cannot become a white dwarf.
Normally, when a lower mass star (like the Sun) runs out of fuel, it collapses (it may expand briefly into a red giant first). The collapse heats the star up, which is where the "white" part comes from.
This happens when the star no longer produces (or rather, converts) energy through nuclear fusion - that is, when it runs out of fuel. Before this happens, the gravitational force is countered by gas pressure, but also by radiation pressure. When there is no longer enough radiation, gas pressure by itself is not alone to keep the star from collapsing into a white dwarf.
Exactly the same way a white hot piece of steel become cool enough to handle.
The energy or heat, is radiated into space over a long period of time. When there is no heat or energy left in the stellar remnant, it becomes a black dwarf, or another cold piece of rock floating around the Universe.
That's the energy reserves of the white dwarf - the leftovers of when it was still producig energy from nuclear fusion, and also, the result of the star collapsing. It no longer produces energy, and will gradually cool down, becoming (after a very, very long time) a "black dwarf".
That's the energy reserves of the white dwarf - the leftovers of when it was still producig energy from nuclear fusion, and also, the result of the star collapsing. It no longer produces energy, and will gradually cool down, becoming (after a very, very long time) a "black dwarf".
That's the energy reserves of the white dwarf - the leftovers of when it was still producig energy from nuclear fusion, and also, the result of the star collapsing. It no longer produces energy, and will gradually cool down, becoming (after a very, very long time) a "black dwarf".
That's the energy reserves of the white dwarf - the leftovers of when it was still producig energy from nuclear fusion, and also, the result of the star collapsing. It no longer produces energy, and will gradually cool down, becoming (after a very, very long time) a "black dwarf".
A planetary nebula is the shell of a red giant, and the white dwarf is the core. As the red giant expands, the shell was blown into the space and became planetary nebula. After the formation of the planetary nebula, the hot core of the red giant was exposed and became a white dwarf.
That's the energy reserves of the white dwarf - the leftovers of when it was still producig energy from nuclear fusion, and also, the result of the star collapsing. It no longer produces energy, and will gradually cool down, becoming (after a very, very long time) a "black dwarf".
The star shrinks as gravity pulls it in, but it gets hotter and denser. This is how it becomes a white dwarf.
An 8 solar mass star can become a stable white dwarf when it reaches a diameter of 100 km. The star has to implode and the core material that is left after the collapse is the white dwarf.
The sun isn't a white dwarf, yet. It is still a dwarf Yellow Star. If it became a white dwarf, we would not be here as life on earth would cease to exist.
A black dwarf.
A white dwarf no longer produces energy through fusion but remains hot from the residual heat of the star it once was. It will radiate that energy away and slowly cool as a result, eventually becoming a black dwarf.
Dwarf stars are dim because they are small, so their luminosity (amount of emitted energy) is low compared to other stars, and low luminosity means more dimness.
The dwarf planet Pluto.The dwarf planet Pluto.The dwarf planet Pluto.The dwarf planet Pluto.
A white dwarf could not become a red dwarf. A white dwarf is a remnant of a dead star. A red dwarf is a star with a very low mass.
It depends on what you consider to be a lot of energy. A red dwarf generates far less energy than other classes of star, but still far more than anything on Earth.
The fate of an isolated brown dwarf depends on its mass. If the brown dwarf is below a certain threshold (about 13 times the mass of Jupiter), it will cool and fade over time, eventually becoming a cold, dark object called a "rogue planet." If the brown dwarf is more massive, it may undergo fusion reactions and become a star, though this is rare for isolated brown dwarfs.
Black Dwarf.
a black dwarf
No. The energy of a white dwarf is simply residual heat.
A black dwarf.
No. A white dwarf is the remnant of a star in which fusion has stopped. There is no hydrogen left. All the energy left in a white dwarf is residual heat.
A white dwarf is not considered a "dead star." It is considered a dying star, but not dead yet. A white dwarf is at its smallest state and could become a supernova when its center runs out of fuel to burn.
A black dwarf [See related question]
A white dwarf no longer produces energy through fusion but remains hot from the residual heat of the star it once was. It will radiate that energy away and slowly cool as a result, eventually becoming a black dwarf.
At that stage, it will no longer produce energy. All the energy it radiates out is its residual heat, and it will gradually get colder and colder. Due to its small size and high density, however, it will take trillions of years for the white dwarf to become a black dwarf.
At that stage, it will no longer produce energy. All the energy it radiates out is its residual heat, and it will gradually get colder and colder. Due to its small size and high density, however, it will take trillions of years for the white dwarf to become a black dwarf.