On Jan/22/2020 at 20:58, Sylvia Else wrote :
On 23/01/2020 11:38 am, Alain Fournier wrote:
As you have probably heard, the star Betelgeuse has been dimming
lately. For now I consider this more of an interesting curiosity than
anything else. But it just seems to just keep on dimming. See for
instance
https://
en.wikipedia.org/wiki/Betelgeuse#/media/File:Betelgeuse_AAVSO_2019.jpg

Does anyone around here have some knowledge about what is going on? Is
there some threshold under which one can say that this isn't just
normal variations? I mean if the magnitude of Betelgeuse went all the
way to 3.0, I would be getting excited about this. But that 3.0 is
just a number I pulled out of thin air. Does someone more
knowledgeable have a more significant number beyond which the
luminosity variation is indicating more dramatic variations?

Any other comments on this?


Alain Fournier

Well, we're all hoping that it's about to go supernova, of coure.

But I don't think anyone can give you a definite answer, because that
would imply a certain knowledge about whether it will go supernova now,
or not.

Perhaps this is what a star does for tens of thousands of years before
it goes bang.

Sylvia.


I just found this:
http://www.astronomerstelegram.org/?read=13410

"If these recent light changes are due to an extra-large amplitude light
pulse on the ~420-day period, then the next mid-light minimum is
expected during late January/early February, 2020. If Betelgeuse
continues to dim after that time then other possibilities will have to
be considered. The unusual behavior of Betelgeuse should be closely
watched."

So the next few magnitude readings will probably put an end to the
excitement about Betelgeuse. Let's hope they don't :-)


Alain Fournier