Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Fozzie on 21/01/2010 10:28:13

Title: Are there really "Magnetic Lines" in space?
Post by: Fozzie on 21/01/2010 10:28:13
On the BBC's Science page "Herschel space telescope captures birth of stars" which can be found at http://news.bbc.co.uk/1/hi/sci/tech/8416263.stm Palab Gosh (BBC Radio Science) who has a science degree from Imperial College narrates a short video where he states that stardust is seen "forming into clumps along magnetic lines". He goes on to talk about "magnetic eddys" when describing how the dust forms a new star.

Please correct me if I'm wrong, but I always thought it was gravity that did the "clumping"!  [???]
Title: Are there really "Magnetic Lines" in space?
Post by: LeeE on 22/01/2010 00:53:39
Gravity, charge and magnetism may all have an effect on how matter clumps together.  Who knows what goes on inside the mind of a journalist though?
Title: Are there really "Magnetic Lines" in space?
Post by: namaan on 22/01/2010 01:02:27
It's not clear from your OP at what stage these magnetic lines are supposed to take effect. Maybe the magnetic lines form after some matter has already clumped together due to gravity? Then the remaining star dust around this 'core' is organized along magnetic fields formed by the growing core?
Title: Are there really "Magnetic Lines" in space?
Post by: yor_on on 23/01/2010 18:14:39
Free space have no 'magnetism'
So there can be no 'magnetic lines'.
Magnetic_field (http://en.wikipedia.org/wiki/Magnetic_field#B_and_H)

Free Space (http://en.wikipedia.org/wiki/Free_space)
Title: Are there really "Magnetic Lines" in space?
Post by: Soul Surfer on 24/01/2010 11:48:03
Researchers are just becoming aware that very weak large scale magnetic fields probably have a big effect on the way that galaxies and larger structures develop.  These fields are in general far to small to be measured directly using the normal spectrographic processes used in stars.  however they can be inferred by the way in which the material is moving because the effects are different from those of gravity alone.

Electrostatic forces are very strong and are probably quickly evened out in large structures.  Electromagnetic forces created by moving charges are much smaller but they tend do persist.  Think of them more like eddies in the flow of material.  A significant amount of interstellar material is ionised and even neutral atoms have small magnetic moments and on a vast scale these can be significant compered with gravitational forces.

The sort of motions induced by electromagnetic processes in natural structure can be seen in the sun and studied on a small scale in the lab the science of magnetohydrodynamics deals with this.
Title: Are there really "Magnetic Lines" in space?
Post by: yor_on on 26/01/2010 15:57:47
You know Soulsurfer. the idea of 'free space' is a strange one. Either it is unattainable, in which case expansion won't be through 'free space' being created inside a times arrow to then become diluted by 'matter like phenomena'. Or it is not unattainable which then seems to say that there actually exist 'free space' being created constantly in all points in space. And in those points there can be no magnetism as magnetism needs a 'medium'.
Title: Are there really "Magnetic Lines" in space?
Post by: Soul Surfer on 26/01/2010 19:38:17
Yor-on

I do not understand what you are talking about or why you are saying it. Static magnetic fields do not require any significant medium other than normal empty space  i.e. no particles. just like photons and static electric fields.
Title: Are there really "Magnetic Lines" in space?
Post by: yor_on on 27/01/2010 01:02:51
"In modern physics, the magnetic (and electric) fields are understood to be due to a photon field; in the language of the Standard Model the electromagnetic force is mediated by photons. Most often this microscopic description is not needed because the simpler classical theory covered in this article is sufficient; the difference is negligible under most circumstances."

And photons are very hard to prove in a vacuum, that's how I see it anyway?