Mass of Progenitors
The purported neutron star of the Puppis remnant
discussed in the first page of the left panel is
of interest for another reason too.
Analysis of the atomic
composition of the supernova remnant using optical spectra, in comparison with stellar
evolution models,
suggests that the mass of the progenitor star that produced the supernova was 25
solar masses.
If this indirect inference is correct, this is the most massive supernova progenitor
known to have produced a neutron star (rather than a black hole).