Talk:Magnetar

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The link in the first sentence to Robert Duncan is pointing to the wrong person of this name.

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[edit] Magnetic Field Strength

This article says:

Magnetars are primarily characterised by their extremely powerful magnetic field, which can often reach the order of 10 gigateslas. These magnetic field's are billions of trillions of times stronger than any magnet created by man on Earth

10 gigateslas = 1010 teslas billions of trillions = an order of 109+12=1021 Implying that man-made magnetic fields have never been more powerful than 10-11 or 10 picoteslas. This is kind of ridiculous.. moreover this page claims otherwise.

Also, the tesla page claims the strongest magnetars recorded have been 10 terateslas, not gigateslas.

I'm not sure if this last fact is right or not, but I'm going to change "billions of trillions" to "millions" to make this article accurately reflect 10 gigateslas as it claims.

Caliprincess (talk) 05:21, 8 January 2008 (UTC)


[edit] Conservation of angular momentum

If the rotation slows, where is the conservation of angular momentum ? In other words, what does it 'push against' in order to slow down ?

Magnetic braking, I searched around here but couldn't find a good article on how it works in stars, how it works in cars though gives an idea on the theory behind it (Electromagnetic brake). This website has some [1] on the stellar version. --Fxer 16:07, July 28, 2005 (UTC)

[edit] Magnetar and categories

While cleaning up the electromagnetism category, I removed categories from Magnetar as articles are generally supposed to be in their most specific category, and Magnetars is a sub-sub-sub category of stars. I was going to, I had yet to do so, add the Category:Pulsar -- the supercat of Magnetar -- as a subcat of electromagnetic radiation, and Category:Magnetar to Magnetism, as opposed to listing individual articles within electromagnetism. The removal of Stellar Phenomena was a mistake I see now. I'm going to remove the electromagnetism and stars categories from Magnetar, and finish adding the Pular and Magnetars cats . Salsb 13:23, August 16, 2005 (UTC)

[edit] The quick and the dead

lethal? If it were so magnetic, wouldn't one be able to stand over it, or wobble up and down between gravity and magnetism? Then wights would have a hard time falling in, though they may be smashed against the walls of their spaceship. lysdexia 12:22, 21 September 2005 (UTC)

At 1000 km from 2 sol mass neutron star gravity is ~15 million gees. Weights will have hard time NOT falling in :)

[edit] Cleanup

This article requires a serious cleanup, it looks atrocious. I wish people would stop simply cut&pasting whole web pages into Wikipedia articles without reformatting, reviewing, editing, thinking... --Jquarry 02:11, 14 December 2006 (UTC)

So I have removed the voluminous block of text which was messily cut & pasted from Robert C. Duncan's website. There was already a link to the bloody thing anyway. Sheesh. --Jquarry 02:18, 14 December 2006 (UTC)

[edit] Proposed merge from quantum electrodynamic threshold

  • Support merge. Not enough information present to be its own article, for the time being. --Christopher Thomas 20:33, 12 April 2007 (UTC)
  • Support Clearly the right idea. Shouldn't need much discussion. Gnixon 21:15, 12 April 2007 (UTC)
  • Support. At this point, of course. linas 23:47, 12 April 2007 (UTC)
  • Support — since I suggested this in the first place, I probably should. Anville 13:34, 13 April 2007 (UTC)

I went ahead with the merge, paraphrasing and rewriting the text because it was a copyvio from Scientific American. Anville 20:00, 13 April 2007 (UTC)

[edit] Short Lifetimes

An earlier version of the article stated that SGRs show violent X-ray and gamma-ray flares, and that via these flares these sources eventually exhaust their energy, at which point they become AXPs with X-ray emission only. This statement has been removed for the following reasons:

  • It is correct that SGRs are phenomenologically defined by gamma-ray flares, while AXPs have relatively steady X-ray emission. However, recent events suggest that this is somewhat semantic, since when SGRs are not flaring, they look just like AXPs [2], and even the most stable and quiet AXPs have now been seen to emit SGR-like gamma-ray flares.[3]. Thus whether a source is classified as an SGR or an AXP seems to depend on how it was first discovered, rather than by any definitive evolutionary state.
  • Observations suggest that the giant flares seen from SGRs do not noticeably drain their energy.[4] It rather seems to be their rapid but on-going braking of their spin period through which they lose energy.[5].
  • The available evidence suggests that SGRs do not evolve into AXPs, but rather if anything the reverse sequence occurs.[6].

Tubbs334 22:39, 20 May 2007 (UTC)

    • OK, thanks for clearing this up. But shouldn't the SGR & AXP articles also be updated with this new info? Or perhaps even a merge between these two? Please let me know your thoughs on this. --193.67.80.4 10:56, 22 May 2007 (UTC)
      • Absolutely - most people think AXPs = SGRs = magnetars, so these should all be one article. Tubbs334 12:47, 22 May 2007 (UTC)

[edit] Galaxy Full of Magnetars

The statement, "The Galaxy is thus probably full of dead magnetars", is unsupported and silly. I'm removing it. --Jquarry 05:45, 23 May 2007 (UTC)

That statement has found its way back into the article again. At least it has a reference this time. Listen, even if Duncan's very rough estimate is correct and 30 million magnetars have formed in the Milky Way... hell let's be generous and call it 100 million... That still represents just 0.1% of all stellar bodies in our galaxy. That hardly qualifies as "full of". Unless you think Japan is "full of" Caucasians, or the Earth's crust is "full of" lead. All right, this time I rewrote the statement so it at least sounds logical, even though TBH I'm not at all comfortable with Duncan's reasoning. --Jquarry 05:16, 31 July 2007 (UTC)

[edit] research

" "This is a breakthrough because we can now distinguish between surface and magnetospheric phenomena, Guver said. " --Emesee 06:17, 21 September 2007 (UTC)

[edit] Formation (percentages unclear)

Question about unclear percentages.

"The supernova might lose 10% of its mass in the explosion [...] —maybe another 80%."

Is that "another 80% of the original mass" is lost (total 90% lost), "80% more than the original 10%" is lost (total 18% lost), or "80% of the remaining mass" is lost (total of 72% lost)? Madmadmadmage (talk) 03:33, 9 December 2007 (UTC)