Emden–Chandrasekhar equation
In astrophysics, the Emden–Chandrasekhar equation is a dimensionless form of the Poisson equation for the density distribution of a spherically symmetric isothermal gas sphere subjected to its own gravitational force, named after Robert Emden and Subrahmanyan Chandrasekhar. The equation was first introduced by Robert Emden in 1907.
Source: Wikipedia — Emden–Chandrasekhar equation (CC BY-SA 4.0)