Gamma Ray Burst 20
Cackmobile writes "The Sydney Morning Herald is reporting that some Australian scientists have been watching a gamma-ray burst. The article makes some good points about the origins of these." Update: 03/21 03:27 GMT by T :
MickDownUnder writes with a link to NASA's press-releasy version, with story, pictures and animations.
What is the news?? (Score:1)
Re:What is the news?? (Score:2, Informative)
Here's a link to an article on Yahoo!News:
LINK [yahoo.com]
SWIFT (Score:5, Informative)
Not much here (Score:4, Informative)
Weeks is appropriate (Score:5, Informative)
The gamma rays themselves persist anywhere from .01 to 1000 s. Even with HETE-2, we have almost no chance of pinpointing the location of the short GRBs. But the long ones last long enough to pinpoint their location with X-ray telescopes. If that happens, then the GRB can be observed across the energy spectrum from X-rays to radio waves. They often take weeks before they dim to the point they can't be distinguished from their host galaxies. The misperception that gamma rays bursts are fleeting comes from the days before the BeppoSAX satellite launch in 1996, when positions could not be located precisely enough for follow up observations in other regions of the spectrum.
Long GRBs (such as the one lst October) are probably caused by hypernovae or collapsars, where a massive star (at least 20x our sun's mass, not the 10-15 solar mass star mentioned in the Sydney Morning Herald) has its core collapse into a black hole, perhaps after collapsing into an intermediate neutron star. The short GRBs are probably the result of mergers between massive compact objects like white dwarfs, neutron stars, and black holes.
Re:Weeks is appropriate (Score:3, Interesting)
Also, does anyone know what the Wolf-Rayet star has to do with anything? Is it a possible burst candidate? I read the origional article and the gsfs.nasa.gov link and I didn't find any mention of this.
Does the "Wolf-Rayec" star classification refer to a massive star about to collapse?
All Astronomy Picture of the Day ( here [nasa.gov]) says about it is that Wolf-Rayec stars are a
Re:Weeks is appropriate (Score:3, Informative)
That was exactly the point in my last post. When the gamma rays are gone the show isn't over.
From this one might assume Wolf-Rayet stars might already have undergone an event which might have caused a GRB (gamma ray burst)?
No. These massive stars have (usually) burned through most of their supply of hydrogen and are furiously burning helum. They are losing their outer
Re:Not much here (Score:3, Informative)
Gamma Ray Bursts (Score:3, Funny)
I thought that was Zaphod Beeblebrox?
HULK Smash!!! (Score:4, Funny)
Re:HULK Smash!!! (Score:2)
Run for your lives! There are scattered reports of the scientists turning into gigantic, green, muscle-bound monsters after beein exposed to the Gamma Ray Burst. Run! Hide! Flee!
Ya that was just moments after said scientists decoded the secret message encoded in the burst which began: "All your base are..."
If I was a sentient life form... (Score:3, Interesting)
Maybe SETI needs to take a closer look at these bursts?
Re:If I was a sentient life form... (Score:1)
Re:If I was a sentient life form... (Score:2)
Hmmmm, they might even be able to shield against it! Ooooh! Technology!
Australian Scientists.... (Score:1)
Science Daily (Score:3, Informative)
This is exciting, seems like we have a first hand look at the formation of a black hole!