The Galactic Empire

[Argonavis]

There has been a few press releases coming out the the AAS meeting in Seattle:

http://www.aas.org/meetings/

but one of the latest is most interesting:

http://news.nationalgeographic.com/news/2007/01/070110-dwarf-galaxies.html

I understood the MW Galaxy had 13 dwarf satellite galaxies, I am not sure what the latest would take this number to.

some models of galaxy formation predict that there should be thousands of dwarf satellite galaxies created as part of the galaxy formation process, perhpas they are there but never formed stars or are too faint.

[hector]

Both the Milky Way and M31 have numerous dwarf galaxies. The local group is a collection of galaxies that are gravationally bound to the Milkyway/M31 pair. Included is the SMC and LMC, M33, NGC6822, IC1613 and about 30 galaxies of smaller size. Many of the Local Group galaxies present themselves as good observing challenges.

[gary]

One of the presentations that came out of the AAS was by Nitya Kallivayalil et. al.
Using the Hubble, they measured the radial velocities of the SMC and LMC and found
them to be about twice that of what was previously thought. They then combined these
velocities with their proper motions.

Turns out that the LMC/SMC may not be gravitationally bound after all, but simply
passing by. Either that or the Milky Way is twice the mass as currently believed.
According to the researchers, the relative velocities between the LMC and SMC
also suggest they are not bound to each other.

Best Regards

Gary Kopff
Mt. Kuring-Gai

[xelasnave]

If one subscribes to the notion that globular clusters are the remains of dwarf galaxies one can for a differnt view of what is going on. There is support for such a view.. their orbits alone would suggest they have been captured one would think.
alex

[xelasnave]

I have said it many times ..if one looks to use the force of attraction to explain things an incorrect view will be arrived at.. Dark enrgy holds galaxies together, (a force of attraction just will not do it..) and dark enrergy is recognised as a "pushing force" so I wonder at what point the unproven force of attraction can be injected to solve any mystery of the Universe. Is there an experiment which demonstrates attraction ..I think not.. it is an assumption built from a continuing human misconception.
alex
alex

[xelasnave]

Space time does not say attraction anywheres that I can find and its absence there must make one wonder. (mind you it does not say "pushing" either to be even sided.)
alex