Thread: We're Doomed.... again!

Just found this article about an up and coming event that will destroy the world....

Daily Telegraph

I'm just going to burn another oak tree to keep me and the world warm!

Litotes

Well the blast wave can't outrun the speed of light, and if it's 3,000 light years away I don't think I'll getting too worried.

Well if you listen to all the hype about global warming we don't have much of an ozone layer left anyway so we're hardly going to miss it are we?

Originally Posted by JoeCivvie

Well the blast wave can't outrun the speed of light, and if it's 3,000 light years away I don't think I'll getting too worried.

There is hope!

At last, an end in sight for to the PC nonsense!

Have we a date ? I'll put in my 5000 year diary,so I don't forget.

Originally Posted by JoeCivvie

Well the blast wave can't outrun the speed of light, and if it's 3,000 light years away I don't think I'll getting too worried.

True, but if we can see that it's gone bang, then the supernova must have happened 3000 years ago, and we are only seeing it now.

So it would all depend on how much slower the blast wave is than the speed of light. 'Flash to bang' sort of thing.

Originally Posted by Phooey

Originally Posted by JoeCivvie

Well the blast wave can't outrun the speed of light, and if it's 3,000 light years away I don't think I'll getting too worried.

True, but if we can see that it's gone bang, then the supernova must have happened 3000 years ago, and we are only seeing it now.

So it would all depend on how much slower the blast wave is than the speed of light. 'Flash to bang' sort of thing.

I think by blast wave they actually mean the flash...... so 'tis more of a 'Flash - f*ck'

Originally Posted by Phooey

Originally Posted by JoeCivvie

Well the blast wave can't outrun the speed of light, and if it's 3,000 light years away I don't think I'll getting too worried.

True, but if we can see that it's gone bang, then the supernova must have happened 3000 years ago, and we are only seeing it now.

So it would all depend on how much slower the blast wave is than the speed of light. 'Flash to bang' sort of thing.

Although unlikely given the time scales involved, it’s possible that the event has already taken place and we are about to find out about it in the form of a second Sun as the light reaches us, being visible during daylight for a few weeks or months. The only possibly significant effect could be the short lived disturbing of bird and animal behaviour as well as plant cycles while the “second Sun� persisted.

If there wasn’t anything in the way the matter shockwave could be just a little behind the “light sphere� and so arrive within a few years of the latter. However, at over 3k light years away the energy density per unit area would be negligible, at best, by the time the wave reached us. Interstellar dust close to the event would absorb almost all of the matter in any case, resulting in a growing nebula visible through a decent set of binoculars within a few years. What would reach us would be a slightly higher than usual high energy particle flux noticeable only through specialised equipment.

Again, given the vast time scales involved, it’s a non-story really, meant for interest, but with the usual media’s alarmist spin. I’d quite like it to happen in my lifetime. I missed the last close one; the Crab Nebula event in 1054:

http://en.wikipedia.org/wiki/Crab_nebula

I'm trying to calculate the effect on the Earth, but I've come up with a problem. What's 20 billion billion billion megatons in SI units? It's bad enough not knowing if the billion is US (1,000,000,000) or UK (1,000,000,000,000), but when you get a unit repeated more than once, I get confused. I mean, is a trillion a thousand billion or a billion billion?

If someone can help, please hurry as we may not have much time...

Well ScouseD, let's just hope Betelgeuse went belly up oh, say... 630 years ago?

[quote="ScouseD"][quote="Phooey"]

Originally Posted by JoeCivvie

I missed the last close one; the Crab Nebula event in 1054:

http://en.wikipedia.org/wiki/Crab_nebula

But it's 1059 now?

Originally Posted by cometcatcher

Well ScouseD, let's just hope Betelgeuse went belly up oh, say... 630 years ago?

Then we've got another 10 years to wait. (it's Approx 640 light years away)

...and what about the bang? If sound doesn't travel through a vacuum, will it be a silent explosion? Without a bang, there's be no blast, so a bit less to worry about.

That's very much 640 'ish', but I'd like to see some of the seriously big observatories up and running before it did go pop

Edit: Puttees, this is the kind of supernova expected in the Times article http://en.wikipedia.org/wiki/Type_Ia_supernova

Originally Posted by Phooey

Originally Posted by cometcatcher

Well ScouseD, let's just hope Betelgeuse went belly up oh, say... 630 years ago?

Then we've got another 10 years to wait. (it's Approx 640 light years away)

I’ve been waiting for Betelgeuse to go supernova since I was a kid, and to be honest I’m getting a little impatient…

The event would certainly be spectacular, but again given the vast distances involved nothing to be overly concerned about. Taking a simple linear approach the energy and matter densities would follow the inverse square law on their way towards us, meaning that again the effects would be negligible, apart that is from a humongous light in the sky for quite a while. That would certainly mess up natural cycles, but there isn’t anything in the fossil record to show that these events, which must have happened in the past, resulted in any sort of catastrophe.