white+dwarf

A white dwarf is a star’s final form after their nuclear fuel is all used up. Near the end of its nuclear burning stage, a star throws away most of its outer atmosphere forming a planetary nebula, but the hot core of the star stays alive. This core turns into a burning hot white dwarf newborn, which cools down over a couple of billion years. That’s basically all we know because earthly machinery is way too weak to take the atmosphere of a white dwarf. A hite dwarf is also called degenerate dwarf. White dwarf was recognised in 1910 by HENRY NORRIS RUSSEL, EDWARD CHARLES PICKERING AND WILLIAM FLEMING. A white dwarf is very hot when it is formed, but since it has no source of energy it will gradually radiate away its energy and cool down.over a long time, a white dwarf cool to temperatures at which it is no longer visible and will become a cold black dwarf.
 * White Dwarf**