White Dwarf
The dense stellar remnant remaining after a low-to-medium mass star exhausts its core nuclear fuel and sheds its outer layers.
Governing formula
P_deg ∝ ρ^(5/3) (Electron Degeneracy Pressure)
SI unit
M_☉ (Mass) or R_Earth (Radius)
In depth
White dwarfs are extremely dense (~10⁹ kg/m³), having masses around 1 M_☉ packed into Earth-sized volumes. Gravitational collapse is prevented solely by quantum electron degeneracy pressure.
Examples in the real world
Sirius B, a white dwarf star orbiting the bright star Sirius A in a binary system.