Because all type Ia supernovae are the product of the same process in similar progenitor stars, they provide a frame of reference for nearby objects.
Their expected neighborhood is near the center because their progenitor stars were the heaviest stars present in the cluster.
This progenitor star was a red supergiant, consistent with the expectations of existing single-star stellar evolution models.
This type of progenitor star has a luminosity 1 to 6 million times that of the Sun.
The spectra of Pair instability supernovae depend on the nature of the progenitor star.
The initial cloud of debris from the progenitor star is dissipating as it moves out into space.
Given the current estimated mass of the black hole, the progenitor star must have lost over 30 solar masses of material.
The prevailing hypothesis is that such a ring was formed 20,000 years before the supernova when the progenitor star devoured a smaller stellar companion.
Four days after the event was recorded, the progenitor star was tentatively identified as Sanduleak -69 202, a blue supergiant.
This shell was likely created by a strong stellar wind from the progenitor star.