Astronomy
A dying star’s luminous shell
Shape an expanding stellar envelope from a round shell into bipolar lobes. Track its expansion age and the fading emission measure.
The model and its limits
Ballistic homologous shell and an n² emission proxy. Ionization, shocks and line ratios are not solved; colours represent an illustrative narrow-band composite.
Equations used in the module
Equations R = vt; n ∝ t^(-3); ∫n²dV ∝ t^(-3)
