Ditribution of stellar debris rich in iron in the supernova remnant Cassiopoeia A. The colored isosurface marks the distribution of iron about 350 years after the supernova explosion (nearly the age of the SNR Cassiopeia A) derived from a magnetohydrodynamic model of a neutrino-driven core-collapse supernova. The opaque irregular isosurface corresponds to a value of Fe density which is at 5% of the peak density; the colors give the radial ejecta velocity in units of 1000 km/s on the isosurface. The semi-transparent quasi-spherical surfaces indicate the forward (green) and reverse (yellow) shocks. The transparent image passing through the center of the remnant is a composite showing optical (Hubble) and X-ray (Chandra) actual observations of the remnant.
MHD simulation performed with the PLUTO code.
Reference: Orlando et al. 2021, A&A 645, A66