Tuesday, December 29, 2009

Regions of Earth's Magnetosphere

Tour of Earth's Magnetosphere

This linked page was created by Randy Russell at University Corporation for Atmospheric Research (UCAR) 

It is an amazing 3d description of the magnetic field around the Earth. It is fun to play with. Good Job.

Monday, December 28, 2009

Zeeman Effect Equations

I finally found a reasonable description of the Zeeman effect.

b = zB cos θ , where z is the Zeeman splitting factor (Hz mG−1), B is the
magnetic field, and θ is the angle of the magnetic field to the line of sight (Crutcher et al.
1993).

This came from the paper "Detection of the Zeeman Effect in the 36 GHz Class I CH3OH maser line with the EVLA" by A. P. Sarma, E. Momjian
http://arxiv.org/PS_cache/arxiv/pdf/0910/0910.1081v1.pdf

Sunday, December 27, 2009

Galactic Magnetic Field

Science 11 May 2007:
Vol. 316. no. 5826, pp. 875 - 878
DOI: 10.1126/science.1139480


http://www.sciencemag.org/cgi/content/full/316/5826/875

The Orientation of the Local Interstellar Magnetic Field
M. Opher,1* E. C. Stone,2 T. I. Gombosi3


Figure 1




Fig. 1. (A and B) Radio source location as a function of the interstellar magnetic field (BISM) direction in (A) the HDP plane and (B) the GAL plane (with {alpha} = 45°). The surface of the heliopause is shown from upwind with respect to the interstellar wind. The isocontours show the strength of the radial component of the interstellar magnetic field, Br, on the heliopause. The green band is the location of the radio sources (at Br = 0). The red arrows show the direction of BISM. (C and D) Same as (A) and (B) but converted to ecliptic coordinates for BISM in (C) the PPG (with {alpha} = 30°) and (D) the GAL (with {alpha} = 45°). The direction of the nose of the heliosphere (diamond) and the GAL (black line) are indicated for reference. The radio sources detected by V1 and V2 are shown as solid circles. Note that the colors are inverted from (C) to (D) because the interstellar magnetic direction was inverted from (A) to (B) (see red vectors in the insets).

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This is vital to the understanding of how stars travel through the galaxy. We only have a few spacecraft that can return data about the interaction between the Sun and the interstellar medium. Voyager 2, Cassini, IBEX and a new one that I don't remember. Dr. Opher; et al, did a great job in mapping the trajectory of the sun through the Milky Way using few datasets.
http://physics.gmu.edu/~mopher/

We are just beginning to understand star motion and it looks to have more to do with Magnetism then gravity. As shown by my published papers, star motion has nothing to do with gravity.

More reading material:
http://arxiv.org/PS_cache/arxiv/pdf/0910/0910.1081v1.pdf