This is from data available on the yt data repository. The outer isodensity surface is of a density ρ = 2 x 10-27 g/cm3, inner purple has a density of ρ = 1 x 10-27 g/cm3. These surfaces are colored by temperature, with darker colors meaning colder gas. The brightness of each vertex is determined as: emissivity ~ ρT2.

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