Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Karen W. on 14/01/2009 07:58:37

Title: What is a Gama Ray Burst?
Post by: Karen W. on 14/01/2009 07:58:37

I want to know what a Gama Ray Burst is and how it is made, what its made of, or from, and have they actually been linked to mass extinction or is that just someones hypothesis, or therory about them?

 I really don't know enough about it to really make any sense f what they are all about.....

Heard it a lot in science fiction
intertainment etc...

 So.... lay it out there nice and easy for me please....

Title: Re: What is a Gama Ray Burst?
Post by: Soul Surfer on 14/01/2009 09:27:45

A gamma ray burst is currently believed to come from from viewing the collapse of a rotating mass into a black hole from an angle close to the pole of rotation.  The reason is that for the mass to collapse inside the event horizon excess energy has to be forced out of the object and the only way it can get out is in a narrow beam at each of the poles.  This turns an already highly energetic process into an extremely high energy process.  If one happened in a nearby galaxy the gamma ray energy could damage the earth but this is a quite unlikely event.   

The gamma ray burst is followed by an optical burst (in fact the energy sweeps down a large range of the electromagnetic spectrum)  and one happend recently that would have been visible to the naked eye if you were looking at the right place at the right time.

Title: Re: What is a Gama Ray Burst?
Post by: LeeE on 14/01/2009 19:07:45

The duration of the burst also fits with the collapse hypothesis, the length of the duration setting a limit on the size of the source.  The bursts are typically just a few seconds long, which suggests that their sources are only of the order of light-seconds across.

According to the wiki article (linked below), some bursts have been seen that are just milliseconds long whilst others have had durations of several minutes.  Even with the upper limit of several minutes though, we're still looking at sources smaller than the diameter of Earth's orbit and well within the range of not very massive stars.

http://en.wikipedia.org/wiki/Gamma_ray_burst (http://en.wikipedia.org/wiki/Gamma_ray_burst)

Title: What is a Gama Ray Burst?
Post by: Vern on 14/01/2009 21:57:15

I wonder if anyone has tried to find out whether a gamma ray burst is confined to a narrow beam and we pass through it.

Title: What is a Gama Ray Burst?
Post by: neilep on 18/01/2009 11:28:37

Gamma Ray bursts are well big !
...even bigger than wifey lighting her bottom burps and believe me, they are huge !!

Title: What is a Gama Ray Burst?
Post by: DoctorBeaver on 18/01/2009 19:20:11

Karen - it may surprise you to know that Gamma Ray Bursts are made of... Gamma Rays!  [;D]