when was it discovered?
First recognized in 1910, and the name coined in 1922.
White dwarf
 The unusual faintness of white dwarfs was first recognized in 1910. The name "white dwarf" was coined by Willem Luyten in 1922.
how many stars r in the milky way It is estimated to contain 100–400 billion stars how can its size be described? It is the second-largest galaxy in the Local Group, it is approximately 890 billion times the mass of the Sun. To compare the relative physical scale of the Milky Way, if the Solar System out to Neptune were the size of a US quarter, the Milky Way would be approximately the size of the contiguous United States. which celestial bodies can be found in this galaxy? It  contain ten billion white dwarfs, a billion neutron stars, and a hundred million stellar black holes. what is the first celestial body? It is also called a degenerate dwarf, is a stellar core remnant composed mostly of electron-degenerate matter. what makes it habitable? It has been proposed that  dwarfs the surface temperatures of less than 10,000 Kelvins could harbor a habitable zone at a distance of c. 0.005 to 0.02 AU that would last upwards of 3 billion years
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White dwarf [SEP] Introduction
Stars of very low mass will not be able to fuse helium, hence, a helium white dwarf may form by mass loss in binary systems. The material in a white dwarf no longer undergoes fusion reactions, so the star has no source of energy. As a result, it cannot support itself by the heat generated by fusion against gravitational collapse, but is supported only by electron degeneracy pressure, causing it to be extremely dense. The physics of degeneracy yields a maximum mass for a non-rotating white dwarf, the Chandrasekhar limit—approximately 1.44 times —beyond which it cannot be supported by electron degeneracy pressure.