Betelgeuse going supernovae

[K.I.L.E.R]

http://science.slashdot.org/story/1...telgeuses-Death-Greatly-Exaggerated?art_pos=7

http://home.ssl.berkeley.edu/forum_thread.php?id=54089

Scary threads about possible destruction of the Earth. Will Betelgeuse destroy our atmosphere? What damage will it do to us?

 

[Arwin]

Too far away.

 

[Kyyla]

http://i.imgur.com/tAJpy.png

Source: http://www.reddit.com/r/science/comments/caf16/betelgeuse_rumors_were_bullshit_no_recent/

 

[Scott_Arm]

Well, if it exploded, it was at least 640 years ago because it's 640 light years away. Pretty cool when you think about that. You're literally viewing ancient history.

 

[digitalwanderer]

But, but, but...what about Ford Prefect?

 

[nbohr1more]

I'm more worried about a Bosenova:

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

See the controversy!

http://www.lhcfacts.org/?tag=bosenova

(long story short: some MIT scientists think that ultra-cold Bosenova experiments create Black Holes...)

 

[Mintmaster]

Well, if it exploded, it was at least 640 years ago because it's 640 light years away. Pretty cool when you think about that. You're literally viewing ancient history.

I'm more amazed by the spectacular coincidence this represents. How many stars are within 700 light years of earth? Maybe 100,000? And on average they last over 10 billion years?

So maybe stars that close happen to die once every 100,000 years, but if these predictions are accurate, we might witness one while our technological prowess is less than a century old.

Oh, and what does it say about me that when reading the story I heard Star Control 2 music in my head?

 

[Fred]

I'm more worried about a Bosenova:

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

See the controversy!

http://www.lhcfacts.org/?tag=bosenova

(long story short: some MIT scientists think that ultra-cold Bosenova experiments create Black Holes...)

The wiki article is terrible, and the lhcfacts site is for crackpots.

 

[digitalwanderer]

People who worry about the LHC make me keekle.

 

[nbohr1more]

I'm not worried about the LHC at all... but Ultra-Cold experiments seem like the perfect way to get neutrons "too close" to each other...

 

[digitalwanderer]

Too close to each other for what? Cohabitation? Coexistence?

It won't produce black holes and it won't destroy the world, not yet anyways.

 

[Grall]

The Earth is bombarded by cosmic rays EVERY DAY that are untold number of magnitudes greater than the LHC can produce even at its maximum power (and it's currently running at, or building up towards roughly HALF power). This has been going on for the entire existence of our solar system, ~4 billion years-ish. And lo, it is still around and hasn't been eaten by any black holes!

The other planets are also likewise bombarded by the same cosmic radiation, including the outer gas giants, all of whom are dozens/hundreds of times the Earth's volume and mass. They are still around too.

The sun holds ~98% of the TOTAL mass of our entire solar system. It is thousands and thousands of times the Earth's volume. It is bombarded too, by massively larger amounts of cosmic rays due to being so much bigger. It is strangely also still around!

Only a crazed idiot would worry about the LHC creating anything remotely dangerous. If by some cosmic random chance a black hole was to be created, it would have the mass of ~2 lead atoms and the gravitational pull of approximately nothing. Its only chance to ingest anything would be by direct collision with something, and since matter is basically empty space it could spend millennia in our Earth's core and hardly grow at all.

Hawkins radiation will make it evaporate before it has a chance to spend millennia anywhere.

When created, it would have the approximate speed of a large fraction of c. It would fly off into space in a microsecond and probably not even hit anything on its way out. Then it would evaporate...

So, why care about any of this...at all?

 

[K.I.L.E.R]

I am only concerned about supernovae destroying the Earth.

 

[nutball]

There've been supernovae closer to the Earth than Betelgeuse (give or take a few tens of parsecs), eg. the progenitor to this object

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

Last time I looked out the window the Earth is still here.

 

[Gubbi]

.And on average they last over 10 billion years?

Stars the size of Betelgeuse burn out a lot faster. It has 20 times the mass of our Sun, but is 100,000 times as luminous, hence it burns hydrogen at 5000 times the rate of our own sun. It is less than 10 million years old.

But that just means that we are lucky to have such a beast to observe in fairly near proximity. The short lifespan of heavy stars make them rare.

Cheers

 

[Grall]

I am only concerned about supernovae destroying the Earth.

AFAIK, there aren't any stars massive enough to supernova that are close enough to harm us.

I'd be more concerned about magnetar starquakes if I was inclined to worry over random things I have no control over... There was one a couple years back that originated from an object somewhere around half the width of the milky way away (I forget which), on the other side of the galactic core. That discharge was powerful enough even at this enormous distance to partially ionize the earth's upper atmosphere and scrambled the circuits of some satellites I believe.

If that magnetar had been only as far away as Betelgeuze when it went off this planet would have been completely sterilized of all life. Probably had its atmosphere blown off, oceans boiled away into space, possibly even rock melted etc by massive X/gamma-ray bombardment...

Magnetars are freakishly dangerous, powerful and scary things. Fortunately for us - again - there doesn't seem to be any close enough around us to really pose any significant threat.

Magnetars could be one reason there doesn't seem to be a space colony in every solar system in this galaxy. It's quite possible each flare-up wipes out life on one or any number of worlds out there in the cosmos...

 

[nbohr1more]

Ack! I should've checked that LHC Facts site before posting it... But I swore that it was pointed to by CERN themselves (or a similar site)...

Anyway, (again) I am not worried about anything that the LHC does...

But a room full of ultra-chilled rubidium atoms setup as a Bose-Einstein Condensate would either be a real Black Hole risk or would produce an immense explosion of Hawkings Radiation...

(this presumes that some scientist would be crazy enough to do ultra-cold experiments with that much material... rather than the microscopic amounts currently used)

 

[pcchen]

But a room full of ultra-chilled rubidium atoms setup as a Bose-Einstein Condensate would either be a real Black Hole risk or would produce an immense explosion of Hawkings Radiation...

(this presumes that some scientist would be crazy enough to do ultra-cold experiments with that much material... rather than the microscopic amounts currently used)

That's not dangerous though. A tiny black hole should explode immediately if Hawking is right, and the energy released should be no more than E=mc^2 for the black hole (which is tiny). Even if it doesn't explode (i.e. there is no Hawking radiation), the chance of it bumping into some mass for it to "grow up" is extremely small as the cross section is, well, extremely small.

 

[nbohr1more]

I just have this superstitious fear of near absolute-zero experiments... they seem way outside of what we normally see in nature...

 

[Mintmaster]

Stars the size of Betelgeuse burn out a lot faster. It has 20 times the mass of our Sun, but is 100,000 times as luminous, hence it burns hydrogen at 5000 times the rate of our own sun. It is less than 10 million years old.

Right, but only a fraction of stars are big enough to go nova (3%, if Wiki is right), hence the use of "average" lifespan.

But that just means that we are lucky to have such a beast to observe in fairly near proximity. The short lifespan of heavy stars make them rare.

Exactly my point. If it actually does explode, it will be a godsend for astronomers.

nutball, Geminga exploded hundreds of thousands of years ago. We don't really know if it had a zero impact on life, but more to my point, there was no intelligent civilization around to watch it.