Hubble - wow

[skepticalbip]

I just found some interesting images from the Hubble team. The space telescope has found large volumes of gas outside galaxies. The gas is only visible around galaxies with active central quasars because, it is suspected, that they are illuminated by energetic bursts of the central quasar.

The question, for me, is if these large volumes of gas exist around galaxies in general but not visible because the parent galaxy doesn’t have an active central quasar to illuminate them. It has been an idea of mine for a while now that the observed rotation of galaxies is due to such gas halos of normal elements (dark matter) containing a mass equivalent to the mass of the observed galaxy rather than some exotic dark matter within the galaxies themselves.

It’s amazing what we find when we look and we have only been able to seriously look for a very short time so far, only since 1990. There are some better "eyes" up there now and even better “eyes” are on the way in the near future.

 

[ryan]

Wouldn't the extra dust have to be equally within the galaxies to hold them together while they spin?

 

[skepticalbip]

Wouldn't the extra dust have to be equally within the galaxies to hold them together while they spin?

No. The center of mass of the galaxy we can see and the surrounding gas would still be the center of the galaxy. So all would orbit that center of mass, however, the distributed gravitational potential including a massive halo would flatten the gravitational well giving us the orbital speeds we see but couldn't explain only assuming the gravitation of the visible matter.