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Fraser
2005-Jul-20, 04:35 PM
SUMMARY: On December 27, 2004, a neutron star flared up so brightly, it temporarily blinded all the X-ray satellites in space for an instant, and lit up the Earth's upper atmosphere. This tremendous blast of energy was from a giant flare created by the neutron star's twisting magnetic field. Objects like this are called magnetars, and they produce magnetic fields trillions of time more powerful than those here on Earth. These fields are so strong they can actually buckle the surface of the neutron star causing these powerful star quakes.

View full article (http://www.universetoday.com/am/publish/x-ray_star_quake_sgr1806-20.html)

What do you think about this story? Post your comments below.

Guest
2005-Jul-20, 05:41 PM
Wow...this seems like a very, VERY late story. :blink:

antoniseb
2005-Jul-20, 05:41 PM
It is interesting that they were able to see this object ringing, and that after three minutes it had settled down to a single dominant frequency. I wonder what it would take to be able to detect the higher frequency signals that died out during the first three minutes, and chart how they died out.

We will learn a fair amount from this event about the structure of Neutron Stars (well Magentars anyway), but we will also learn a lot about what kind of instruments we'd need to learn even more from the next time one of these events happens.

antoniseb
2005-Jul-20, 05:44 PM
Originally posted by Guest@Jul 20 2005, 05:41 PM
Wow...this seems like a very, VERY late story
The detection and analysis of the ringing is something that has only just been released. There are a lot of astronomy stories that are published many months, or even a few years after the observed event.

Duane
2005-Jul-20, 06:34 PM
This is a neat story, and once again seems to provide another straw of support for the existance of magnetars. I wonder what the effect of this blast would have been on planets harbouring life much closer (like within a couple of hundred light years) to this explosion.

wstevenbrown
2005-Jul-21, 01:50 AM
Not everyone thinks that this event, or SGRs in general represent an isotropic energy release:

http://arxiv.org/astro-ph/0504638

Best regards-- Steve

Mild mannered
2005-Jul-21, 09:44 AM
Originally posted by antoniseb@Jul 20 2005, 05:41 PM
It is interesting that they were able to see this object ringing, and that after three minutes it had settled down to a single dominant frequency. I wonder what it would take to be able to detect the higher frequency signals that died out during the first three minutes, and chart how they died out.

Refering to the key of F sharp comment in the story.
I'm a barbershop singer (by hobby) and know that when we sing a certain note in quartet we get both overtones and undertones. I agree with Ant it would be nice to see agraph of the complete range of frequencies the ringing produced.

We've had articles before about harmonics in the early Universe - what key it was in etc and personally I always find them fascinating. And I don't think it was too late - Space today ran the same story on the 18th so it's still a very current topic.

Don Alexander
2005-Jul-21, 10:35 AM
It's nice to see that the RXTE mission, which is really ancient (it will soon be in space for a decade, having been launched on December 30, 1995), is still producing beautiful results! :D

Nereid
2005-Jul-22, 08:16 PM
In another internet discussion forum, a member asked about the possibility of hadronic resonances existing in neutron stars, and of there ever being any observation that could test for the existence (or non-existence) of these.

I responded "not in the lifetimes of anyone reading this message today" (in effect); reading this news story, I realise I may have been wrong! :o

'Star quakes' on magnetars are like super-duper-mega-giga earthquakes; they can be probes for the internal composition of the neutron star. They are like asteroseismology on steroids, with the observations being made at far higher frequencies than the pedestrian optical wavelengths used for probing the internal state of the Sun (helioseismology).

And who knows, maybe in a decade or three neutrino and gravitational wave detectors will be sufficiently sensitive to pick up an unambiguous sig for a deep-buried layer of excited hadronic resonances! B) :D