Page 2, Stellar Remnants: [Previous Page] [Next Page] [Class Home Page] Text Pages 299 - 302

Here is a REAL picture of a sun-like star with a companion White Dwarf. Sirius A and B are very close, which helps us detect the faint White Dwarf, Sirius B. Sirius B is the small white dot to the left of the bright star, lying in one of the spikes in the bright stars light.


Remnant stars are no longer fusing atoms at their centers. They "hold" themselves up via different processes: Degenerate Pressure!!


Webster defines degenerate as ``having sunk to a lower and usually corrupt and vicious state''


In this scientific situation, we mean a state in which the star is mathematically (structurally) simpler. For instance, the density and temperature are no longer coupled! As the White Dwarf cools, it does NOT collapse.


White Dwarfs use: Electron Degeneracy


The atoms in the White Dwarf are crushed together to such a state that the electron "clouds" are essentially touching each other. The temperature of those electrons is irrelevant, the pressure holding up against gravity is due just to the ``size'' of the electron orbits.


However! At some point, even Electron Degeneracy does not work. The remnant hits the "Chandrasekhar Limit"..


IF the mass of the remnant star is GREATER THAN 1.4 M suns, Electron Degeneracy will not be enough to maintain the structure of the star against gravity!!