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View Full Version : Hidden Planet Disturbs a Ring of Dust



Fraser
2007-Jun-13, 04:25 PM
You can't see it, but there's a Neptune-sized planet hidden in a ring of dust around the star Fomalhaut. At least, this is according to new research from the University of Rochester. ...

Read the full blog entry (http://www.universetoday.com/2007/06/13/hidden-planet-disturbs-a-ring-of-dust/)

iantresman
2007-Jun-13, 11:18 PM
The Press Release (http://www.rochester.edu/news/show.php?id=2928) mentions that they are "Treating the ring like a hydrodynamic structure".

I was wondering why they do not treat the dust in the ring as a magnetohydrodynamic structure? The dust MUST be charged due to its interaction with the electrons in the plasma in the interstellar medium? [Added:] And there must be a magnetic field since all cosmic plasmas are magnetic?

Tobin Dax
2007-Jun-14, 12:05 AM
The Press Release (http://www.rochester.edu/news/show.php?id=2928) mentions that they are "Treating the ring like a hydrodynamic structure".

I was wondering why they do not treat the dust in the ring as a magnetohydrodynamic structure? The dust MUST be charged due to its interaction with the electrons in the plasma in the interstellar medium? [Added:] And there must be a magnetic field since all cosmic plasmas are magnetic?

It's possible that they are using MHD, but didn't include that really big word in the press release.

Another option is that MHD is just to expensive in computer time/resources to use for this project, so they're ignoring any possible magnetic component because they are actually able to model it that way.

Northwind
2007-Jun-14, 06:18 AM
Another option is that MHD is just to expensive in computer time/resources to use for this project, so they're ignoring any possible magnetic component because they are actually able to model it that way.

Absolutely dumbfounded :confused:

Ignore the magnetic(electric) field??

Why?

Tobin Dax
2007-Jun-14, 08:08 AM
Absolutely dumbfounded :confused:

Ignore the magnetic(electric) field??

Why?

Because you couldn't do it otherwise. MHD is more complicated that non-magnetic hydrodynamic equations, and sometime that complication is prohibitive. The only way to model the system with the technology you have access to is by assuming no magnetic component and seeing what results you get that way. They can always be built upon later.

Nick4
2007-Jun-15, 06:09 AM
That lookes like a pic out of lord of the rings.