White dwarf star and Earth. Computer artwork comparing a white dwarf star (left) with Earth. A white dwarf star is the collapsed core of a star,containing extremely dense material. This one has half the mass of the Sun (about 170,000 Earths) in the volume seen. The star's core collapsed because the nuclear fusion stopped,removing the outwards pressure that prevented a collapse under its own weight. The star's outer layers were lost to form a planetary nebula (not seen). White dwarfs shine only by their remaining heat,and gradually cool and go out over trillions of years. The Sun will end up as a white dwarf star,smaller than this one,some 5 billion years from now | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Garlick, Mark |
Taille de l’image : | 4200 px × 2940 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |