I What Milky Way stars could go supernova to < +3 at any time?

[swampwiz]

(I use +3 as the cutoff as that seems to be the limit of easily visible stars.) Yes, I know that Betelgeuse could go up in a < -10 blaze of glory, but I wonder what other ones are out there.

On a side note, how fast could the big observatories move to it to observe it? And how quickly would it be noticed at all?

 

[swampwiz]

There are many stars that are visible to the naked eye and have an apparent magnitude of +3 or brighter. Some examples include Sirius, Canopus, Alpha Centauri A and B, Vega, Capella, Arcturus, and Rigel. There are also many other stars that are visible to the naked eye but have an apparent magnitude fainter than +3.

Regarding your second question, the speed at which observatories could move to observe Betelgeuse depends on a number of factors, including the distance to the star, the location of the observatories, and the availability of suitable telescopes and other equipment. Betelgeuse is located approximately 642.5 light-years from Earth, which means that it would take a very long time for a spacecraft or other astronomical observatory to travel there.
I hope it helped.

I meant what stars could go as bright as +3 at the peak of their supernova, not current stars.

This weird answer sounds like it was generated by a bot.

 

[Vanadium 50]

This weird answer sounds like it was generated by a bot.

Some people think that's funny.

You're not going to get a list.

First, your magnitude is not constraining. SN1987a wasn't even in our galaxy and it was brighter than 3.

Next, there are thousands upon thousands of stars who are likely progenitors. If we get on average one SN every 30 years and could tell within 30,000 years when one was nearing the end (and we can't) that would be a thousand stars. Of these many thousands of stars, most don't have names, just catalog numbers, and some are obscured by dust and gas.

You want some possibilities: Sher 25 and Eta Carinae are likely to go "soon".

 

[Cerenkov]

(I use +3 as the cutoff as that seems to be the limit of easily visible stars.) Yes, I know that Betelgeuse could go up in a < -10 blaze of glory, but I wonder what other ones are out there.

On a side note, how fast could the big observatories move to it to observe it? And how quickly would it be noticed at all?

https://snews2.org/

The Super Nova Early Warning System is designed to give electromagnetic telescopes a warning ahead of the supernova's light.

The principle was first demonstrated when neutrinos from supernova SN1987a preceded that explosion's light by two to three hours.

https://en.wikipedia.org/wiki/SN_1987A

Thanks,

Cerenkov.