Which is the best description of a white dwarf star?

A white dwarf star, also called a degenerate dwarf, is a stellar core remnant composed mostly out of electron-degenerate matter. A white dwarf is quite dense, its mass may be comparable to that of the Sun, while its volume could be comparable to that of Earth.

What main elements are present in a white dwarf star?

The majority of white dwarfs are thought to be made mostly of carbon and oxygen. In stars like the Sun, the inward pull of gravity is balanced by the outward push of the high-temperature hydrogen in the center fusing into helium and releasing energy in the process. There is no nuclear fusion in a white dwarf.

Is a white dwarf star high or low mass?

A low or medium mass star (with mass less than about 8 times the mass of our Sun) will become a white dwarf. A typical white dwarf is about as massive as the Sun, yet only slightly bigger than the Earth. This makes white dwarfs one of the densest forms of matter, surpassed only by neutron stars and black holes.

How do you identify a white dwarf?

Many nearby, young white dwarfs have been detected as sources of soft, or lower-energy, X-rays. Recently, soft X-ray and extreme ultraviolet observations have become a powerful tool in the study the composition and structure of the thin atmosphere of these stars.

What is a white dwarf simple definition?

White dwarfs are stars that have burned up all of the hydrogen they once used as nuclear fuel. Fusion in a star’s core produces heat and outward pressure, but this pressure is kept in balance by the inward push of gravity generated by a star’s mass.

How does a white dwarf generate its energy?

Stars like our sun fuse hydrogen in their cores into helium. White dwarfs are stars that have burned up all of the hydrogen they once used as nuclear fuel. Fusion in a star’s core produces heat and outward pressure, but this pressure is kept in balance by the inward push of gravity generated by a star’s mass.

How powerful is a white dwarf star?

The physics of degeneracy yields a maximum mass for a non-rotating white dwarf, the Chandrasekhar limit—approximately 1.44 times M ☉—beyond which it cannot be supported by electron degeneracy pressure.

Is a red giant hotter than a white dwarf?

A white dwarf has a higher surface temperature than a red giant star.

What eventually happens to white dwarf stars?

Tiny red dwarfs may have an extended lifetime, but eventually they, like all other stars, will burn through their supply of fuel. When they do, they will become white dwarfs, dead stars that no longer undergo fusion at their core. Eventually, the white dwarfs will radiate away all of their heat and become black dwarfs.

Which stars are white dwarfs?

White dwarf star. White dwarf stars are occasionally found in binary systems, as is the case for the white dwarf companion to the brightest star in the night sky, Sirius. White dwarf stars also play an essential role in Type Ia supernovae and in the outbursts of novae and of other cataclysmic variable stars.

What are white dwarf stars and how do they form?

White dwarfs: Compact corpses of stars Formation. Main-sequence stars, including the sun, form from clouds of dust and gas drawn together by gravity. Characteristics. When a star runs out of fuel, it no longer experiences an outward push from the process of fusion and it collapses inward on itself. One last kick.

What percentage of stars are white dwarfs?

White dwarfs are the collapsed remnants of stars that were once about eight times the mass of our Sun or lighter. Our Sun, for example, after it first puffs up into a red giant in about 5 billion years, will ultimately slough off its outer layers and shrink down into a compact white dwarf. About 97 percent of all stars become white dwarfs.