Astronomy

A star the size of a planet

Add mass to a cold white dwarf and watch its radius shrink. Compare its density and surface redshift with the familiar scale of Earth.

By Mykhailo Makarov

Actual application image

The model and its limits

Zero-temperature Nauenberg mass–radius approximation for electron molecular weight 2. No finite-temperature envelope, crystallization or accretion instability.

Equations used in the module

Equations
R = 0.0112R☉ √[(M_Ch/M)^(2/3)-(M/M_Ch)^(2/3)]; M_Ch=1.44M☉

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