Is Betelgeuse going supernova
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Robert Chandler
Feb 9, 2021, 4:15:36 PM2/9/21
to croydo...@googlegroups.com
I remember during one of my first visits to Kenley (back when you could move around and meet people – late 2019) a discussion with William regarding whether Betelgeuse was going supernova. At the time it was explained to me that the dimming and brightening reported at the time was natural fluctuation.
Recently in some of the press there has been speculation that it is going supernova, wishful thinking or something to look forward to?
My luck when it does happen, just like the Great Conjunction of Saturn and Jupiter, the clouds will have a say.
Robert
William Bottaci
Feb 9, 2021, 5:17:57 PM2/9/21
to croydo...@googlegroups.com
Hello Robert
Betelgeuse is a variable star, with two causes of regular variability
and thus two periods, so the variability we see is the superimposed
resultant. Each is not that regular so hard to predict. It turned out
that the period of dimming coincided with both cycles being at a
minimum, but this could not have been the full story. You have to note
who writes the reports at the time, because they may not be as
authoritative as they seem, and many made no claim to be so.
More recent observations have shown expanding material from the
surface, which is now thinning. It was this material which obscured
its brightness. That, and its usual pulsations added to the mix. Large
stars, even old ones, tend to be a bit on the unstable side; the
hydrostatic equilibrium is not so well balanced, so these things
happen to such stars. The mass of Betelgeuse assures that one day it
will go supernova - it's easily big enough - but when? In fact it is
these pulsations (some of them) - which show that Betelgeuse is still
burning helium - indicating that a supernova explosion isn’t going to
happen anytime soon.
A complication is that modelling shows that such old large stars
generate large sunspots, however it'd have to be an unusually large
one to account for dimming that we could see. These must have happened
and will happen again.
If it was imminent then we wouldn’t know, simply because events happen
fast when near the end and the 'information' wouldn’t have time to
reach the surface. So reports of an imminent supernova would be
unfounded anyway. Still, makes a good story, eh?
When it does explode, are we in danger? Not really; we're some
distance away (actually a bit closer than has been thought of in past
years). It also depends on how it explodes, the explosion is unlikely
to be symmetrical and an examination of magnetic fields, spin
direction etc show that we are probably not in the direction where the
greatest effect will take place. Not that I was worried...
The one thing we can wish for, is that it doesn’t happen in daylight,
when Betelgeuse is on the other side of the Sun. That really would be
bad luck, for a show.
Astronomers are divided. On the one hand its occurrence at night time
means it can be better studied. On the other hand we can forget about
observational astronomy for many months, apart from space borne
telescopes. Nature is going to be very confused.
Then again, in the future who knows what the fate of astronomy will
be. What with the crazy levels of light pollution, and the even
crazier number of low orbiting satellites providing super fast
internet speeds. The only cheerful thought is that by then amateur
space telescopes might just about be affordable, so we'll need those
satellites...
William
On Tue, 9 Feb 2021 at 21:15, Robert Chandler <rob...@appendixb.co.uk> wrote:
I remember during one of my first visits to Kenley (back when you
could move around and meet people - late 2019) a discussion with
Betelgeuse is a variable star, with two causes of regular variability
and thus two periods, so the variability we see is the superimposed
resultant. Each is not that regular so hard to predict. It turned out
that the period of dimming coincided with both cycles being at a
minimum, but this could not have been the full story. You have to note
who writes the reports at the time, because they may not be as
authoritative as they seem, and many made no claim to be so.
More recent observations have shown expanding material from the
surface, which is now thinning. It was this material which obscured
its brightness. That, and its usual pulsations added to the mix. Large
stars, even old ones, tend to be a bit on the unstable side; the
hydrostatic equilibrium is not so well balanced, so these things
happen to such stars. The mass of Betelgeuse assures that one day it
will go supernova - it's easily big enough - but when? In fact it is
these pulsations (some of them) - which show that Betelgeuse is still
burning helium - indicating that a supernova explosion isn’t going to
happen anytime soon.
A complication is that modelling shows that such old large stars
generate large sunspots, however it'd have to be an unusually large
one to account for dimming that we could see. These must have happened
and will happen again.
If it was imminent then we wouldn’t know, simply because events happen
fast when near the end and the 'information' wouldn’t have time to
reach the surface. So reports of an imminent supernova would be
unfounded anyway. Still, makes a good story, eh?
When it does explode, are we in danger? Not really; we're some
distance away (actually a bit closer than has been thought of in past
years). It also depends on how it explodes, the explosion is unlikely
to be symmetrical and an examination of magnetic fields, spin
direction etc show that we are probably not in the direction where the
greatest effect will take place. Not that I was worried...
The one thing we can wish for, is that it doesn’t happen in daylight,
when Betelgeuse is on the other side of the Sun. That really would be
bad luck, for a show.
Astronomers are divided. On the one hand its occurrence at night time
means it can be better studied. On the other hand we can forget about
observational astronomy for many months, apart from space borne
telescopes. Nature is going to be very confused.
Then again, in the future who knows what the fate of astronomy will
be. What with the crazy levels of light pollution, and the even
crazier number of low orbiting satellites providing super fast
internet speeds. The only cheerful thought is that by then amateur
space telescopes might just about be affordable, so we'll need those
satellites...
William
On Tue, 9 Feb 2021 at 21:15, Robert Chandler <rob...@appendixb.co.uk> wrote:
I remember during one of my first visits to Kenley (back when you
Robert Chandler
Feb 9, 2021, 5:22:50 PM2/9/21
to croydo...@googlegroups.com
Thank you William. So fake news again as you said a year and a half ago. Some things don't change. Hope you are keeping well.
See you all, work permitting, in the Altair Arms on Friday
Robert
Robert
From: croydo...@googlegroups.com <croydo...@googlegroups.com> on behalf of William Bottaci <w.bo...@gmail.com>
Sent: Tuesday, February 9, 2021 10:17:39 PM
To: croydo...@googlegroups.com <croydo...@googlegroups.com>
Subject: [croydonastro - 6776] Is Betelgeuse going supernova
Sent: Tuesday, February 9, 2021 10:17:39 PM
To: croydo...@googlegroups.com <croydo...@googlegroups.com>
Subject: [croydonastro - 6776] Is Betelgeuse going supernova
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