Betelgeuse Supernova

[JamesF]

They don't last very long though, and if it were a daytime SN then presumably some night-time imaging would still be possible?

James

[Shibby]

Yes you have a point there, Orion is a daytime constellation during the summer...

I have just read that it would likely dim rapidly 2-3 months after going supernova.

[MAN or ASTROMAN]

A Betalgeuse SN in our lifetime would indeed be spectacular,but for how long? Certainly,the constellation wouldn't look the same,and old Orion would be a bit put out with his shoulder going bang.Puts my recurrent rheumatic shoulder twinges into perspective(!)

[MAN or ASTROMAN]

Thanks Shibby for the timescale-was still typing as your post came through.

[Peter Drew]

I too, would like to see a daytime supernova in my lifetime, as long as it wasn't the Sun.

[JamesF]

I too, would like to see a daytime supernova in my lifetime, as long as it wasn't the Sun.

Now if that were to happen an awful lot of scientists would be quite surprised. But not for very long

James

[Spec-Chum]

At least they'd have 8 minutes of ignorant bliss

Actually, that raises another thought. Kinda freaky that the sun could have exploded 8 minutes ago and we'd have no idea. Scary when you think about it like that...

[Carbon Brush]

The photons I captured from M31 a few nights back left that galaxy over 2 million years ago.....

To try and put that into terms we can relate too is very hard.

Can't lay claim to this one, but I liked the analogy.

About the time the apes had left the trees and were just starting to spread and perhaps be called precursors of humans, light we see now left the Andromeda galaxy.

[Spec-Chum]

Gives me goosebumps just thinking about it!

[DirkSteele]

It is remarkable that a lot of the details about Betelgeuse remain under debate, including crucially its mass and exact distance. It is generally agreed that the mass is in excess of 10 times that of the sun, which means it is likely going to be a Type II supernova. Unlike the standard candle Type 1a supernovae, the maximum brightness varies but the average absolute magnitude is -16 to -17 (though some have reached -22). The Milky Way has an absolute magnitude of about -20.5

Absolute magnitude is the value of celestial objects apparent magnitude if the object was 10 parsecs from the earth (1 parsec = 3.2616 light years). The absolute magnitude brightness relationship is the same as visual magnitude. A factor of 2.512 ratio of brightness corresponds to a difference of 1.0 in magnitude.

There is a simple equation that relates absolute magnitude to apparent magnitude:

M_abs = m_ap – 5 * ((log₁₀ d) – 1)

Where

M_abs = Absolute magnitude

m_ap = apparent magnitude

d = distance in parsecs

We can simply rearrange this equation to solve for apparent magnitude as we believe we have a value for absolute magnitude of a type II supernova.

m_ap = M_abs – 5* (1 + Log₁₀ d)

Taking the accepted distance of 640 light years (approx 196 parsecs) we get a value of -10 to -11. It would likely reach that peak brightness within 15 to 20 days and would decay to 10% of peak brightness over the next 50 to 150 days. Definitely bright enough to see during the day and close to full moon brightness (-12.7 is the average full moon). So it looks like that the moon will have a rival in brightness when Betelgeuse does go Supernova. In which case I suggest everyone get set for a couple of months of planetary only observing.

If it turned out to be a bright Type IIn (-22 absolute magnitude), the apparent magnitude would exceed -15!

[Josh Wilson]

Huh? That's very confusing. Anyway, that's brighter than the moon and almost half the brightness of the sun. That won't even be safe to look at through a telescope without an ND Filter!!!

[cantab]

The magnitude scale isn't linear, so it wouldn't be anything like "half the brightness of the Sun".

[Josh Wilson]

Oh, whoops forgot. Isn't 1 magnitude about 2 times fainter/ brighter than the next?

[Astro-Nova]

I hate the fact your not able to see things happen light years away before light actually reaches us. I am so interested in astronomy that I want to know as many things as possible and still be alive to know all these things. We would miss a lot of things in our lifetime. It is a tease to me knowing that something big might have happened and may happen right now and we will never know about it in our lifetime.

Shows that compare to the universe, our lives are very very short

[Ganymede12]

M51 is 37 million light years away so we see it as it was 37 million years ago.

To put that into perspective - we see M51 as It was the last time I got out with my telescope!

[astrofox]

Its a product of our classical thinking that we still refer to events as occuring simultaneous across the universe. They don't and can't. In fact from our time frame which is the only one valid to us as observers, Betelgeus cannot go supernova before we see it. Time is a dimension and travels at the speed of light.

[NGC 1502]

When I saw the headline I sprayed coffee all over me keyboard

[Vega26]

It will be ashame that the most recognisable constellation would be changed forever, but that is something that I would feel very privileged to see.

[DirkSteele]

Oh, whoops forgot. Isn't 1 magnitude about 2 times fainter/ brighter than the next?

As I said in my original post...." A factor of 2.512 ratio of brightness corresponds to a difference of 1.0 in magnitude."

[skywatcher250]

its staggering to think of timescales... i thin my favorite one (or most scary one) is by the time anyone receives any of our signals or we receive any of theirs either civilization may have been wiped out many thousands if not millions of years ago

[glowjet]

" I've seen things you people will never see, attack ships on fire off the shoulder of Orion, C beams glittering in the darkness at the Tannhäuser gate " Blade Runner, pure fiction I know, but the wonders of space and time are so vast that many have difficulty getting their heads round it, like Astro Fox's statement " Betelgeuse can not go supernova before we see it " so if in reality it exploded 100 years ago, at this present moment in time, we can not say it went supernova until we see at the end of the next century. But what of the advancements in telescopes and science in years to come, " Scientists and Astronomers now have positive evidence, from a long study of the red giant that it exploded some 100 yeas ago " it was announced to_day

John.

[K3ny0n]

So does that mean "we" can see it in 100 years?

[sologuitarist61]

So does that mean "we" can see it in 100 years?

I'll only be 165, shouldn't be a problem

[glowjet]

Betelgeuse is some 500 LY from us, who knows what advancements will be made in Science and Astronomy 200 years from now, which is why I suggested the theoretical news report. I should have added August 3rd 2212. Just a thought, as space and time is difficult to grasp at the best of times Thinking about it Frederik is quite right of course

John.

[Interested]

I don't want anything to 'bright' happening in the sky - the light pollution in Bristol is bad enough as it is!