Up until the supernova in the Larger Magellanic Cloud, theory suggested that there were two types of supernovae: the total implosion-explosion of a white dwarf growing beyond Chandrasekhar’s Limit, and the implosion-explosion of a red giant that had produced a non-exothermically-fusible iron core.
As I understood the reports, the particular star that supernova’ed was a “blue giant” – a star towards the top of the main sequence – and that this would cause substantial rethinking of what caused supernovae.
First question: Did this prove out to be true, and if so, have they determined a new generally-accepted theory for their causes?
Second question: A popular work on novae and supernovae published before 1987 suggested that the three most probable relatively nearby stars to “go” were, in order, Eta Carinae, Betelgeuse, and Mira, with Ras Algethi and a couple of other red giants farther down the list. Can anyone speak to which stars are now considered most likely? Is it the same three?