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Gamma-ray bursts are a threat to life

cerncourier.com

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Re: Gamma-ray bursts are a threat to life

#11

Post by indrax »

viggity wrote: post #7

can someone comment on the legitimacy/reliablity of the "Cern Courier". The article seems legit (no tin foil hats), but that font. woof, it makes it look super amateur.

>Produced for CERN by IOP Publishing

>©COPYRIGHT CERN 2007 for the content of CERN Courier and images and logos identifying CERN.

>©COPYRIGHT IOP 2007 for the design, format and typography of the CERN Courier Web Pages, ...

The author appears to be an astrophysicist, and you may know CERN from such products as the Large Hadron Collider and the World Wide Web.

Re: Gamma-ray bursts are a threat to life

#12

Post by saboot »

viggity wrote: post #7

can someone comment on the legitimacy/reliablity of the "Cern Courier". The article seems legit (no tin foil hats), but that font. woof, it makes it look super amateur.

I know what you mean by 'that font', you must be using chrome on windows.

Apparently it's a 'bug' in their CSS, they are aware of the issue but haven't fixed it yet, http://www.reddit.com/r/Physics/comments/2l2ijj/the_brookhav...

Re: Gamma-ray bursts are a threat to life

#13

Post by colordrops »

lxe wrote: post #6

This makes a lot of assumptions about extra-terrestrial life. This article assumes that all "life" depends on a protective ozone layer and that it's similar to life on Earth.

The article doesn't assume that all life depends on a protective ozone layer. The article states several times that life like that on earth depends on a protective ozone layer.

Re: Gamma-ray bursts are a threat to life

#14

Post by fiatmoney »

benbreen wrote: post #4
tectonic wrote: post #2

Is this the Great Filter?

Certainly seems like one of them, if this claim is true: "The Milky Way would therefore be among only 10% of all galaxies in the universe – the larger ones – that can sustain complex life in the long-term."

Actually, filters that select on galaxy scale are unlikely to be the "great filter", because we don't seem to see any artificially generated signals coming from within our own galaxy. This particular filter does strike within our own galaxy though, just to a lesser degree.

So maybe.

Re: Gamma-ray bursts are a threat to life

#15

Post by cubano »

I know I may get dinged for this observation, but it is something that really bothers me about certain types of forecasts...be it weather or things of this sort...

That would be the "50% forecast", which, when examined with a bit of thought, really is saying "well, maybe it did, and maybe it didn't...we don't really know but hey, doesn't 50% sound scientific!"

For sure, GRBs are scary, potentially life-wiping events, but, really..don't we deserve better than a coin-flip?

Re: Gamma-ray bursts are a threat to life

#16

Post by moyix »

benbreen wrote: post #4
tectonic wrote: post #2

Is this the Great Filter?

Certainly seems like one of them, if this claim is true: "The Milky Way would therefore be among only 10% of all galaxies in the universe – the larger ones – that can sustain complex life in the long-term."

I thought the Fermi Paradox (and hence the Great Filter) was about the absence of life originating in our own galaxy? I don't think anyone has suggested that any species is likely be able to cross intergalactic distances.

Re: Gamma-ray bursts are a threat to life

#17

Post by Steuard »

viggity wrote: post #7

can someone comment on the legitimacy/reliablity of the "Cern Courier". The article seems legit (no tin foil hats), but that font. woof, it makes it look super amateur.

Speaking as a high energy physicist, they're absolutely a legitimate publication. I don't read it regularly, but the CERN Courier has been part of particle physics culture for a very long time (maybe since CERN was founded).

Re: Gamma-ray bursts are a threat to life

#18

Post by acadien »

cubano wrote: post #15

I know I may get dinged for this observation, but it is something that really bothers me about certain types of forecasts...be it weather or things of this sort... That would be the "50% forecast", which, when examined with a bit of thought, really is saying "well, maybe it did, and maybe it didn't...we don't really know but hey, doesn't 50% sound scientific!" For sure, GRBs are scary, potentially life-wiping events,…

It's just statistics. You look at how often we see GRBs, how long they last (on average), how intense they are (on average) then do a big time integral and figure out the odds of a big one hitting earth over such and such a period of time. There is no better than a coin-flip, the coin flip is the odds of it having happened (by the author's approximations). If I can help explain any further please let me know.

Re: Gamma-ray bursts are a threat to life

#19

Post by austinz »

Is the gamma-ray burst a spherical field, or is it a narrow, directed cone? If the latter, I wonder how the burst spreads/diffuses as it travels and what sort of equation governs the energy flux with respect to distance and initial conditions.

Re: Gamma-ray bursts are a threat to life

#20

Post by pixl97 »

austinz wrote: post #19

Is the gamma-ray burst a spherical field, or is it a narrow, directed cone? If the latter, I wonder how the burst spreads/diffuses as it travels and what sort of equation governs the energy flux with respect to distance and initial conditions.

Beams from my understanding

https://en.wikipedia.org/wiki/Gamma-ray_burst#Energetics_and...

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