My theory on the origin of globular clusters

[triclon]

I got to thinking about how stars in globular clusters are similar to stars in the nucleus of our galaxy, both made mostly of population II stars. I also got to thinking about what gave globular clusters their eccentric orbits that exist outside the plane of our galaxy. What if globular clusters are the remaining galactic nuclei of smaller dwarf galaxies that have gravitationally interacted with and have been absorbed into our bigger galaxy. That would explain why globular clusters have similar stars to the nucleus of our galaxy, since the clusters were once galactic nuclei themselves. It would also explain why they orbit outside our galaxy's plane like they do. More massive galaxies have more globular clusters, perhaps because the bigger the galaxy, the more gravity it has and the greater number of smaller galaxies it can interact with and capture.

[grav]

Apparently, something along those lines is already being considered, according to this article from Wiki. I just happened to be reading up on it when you posted.

An even more recent idea is that significant portions of the stellar halo could be stellar debris from destroyed dwarf galaxies and globular clusters that once orbited the Milky Way. The halo would then be a "new"er component made of "recycled" old parts!

[Tim Thompson]

There is nothing ATM about the idea that at least some globular clusters are the remnants of dwarf satellite galaxies that have been devoured by the Milky Way. Certainly this is the mainstream thinking about the largest globular clusters, especially Omega Centauri (i.e., Mc William & Smecker-Hane, 2005 and follow the links to papers which cite this one).

[triclon]

Oh interesting. Well I didn't see a mainstream theory forum so if there's a better place, mods feel free to move this thread.

[Thanatos]

Globular clusters do not display one of the characteristics typical of dwarf galaxies - dust. The evolution must be different. While both coalesced from primordial globs, the dust and gas remaining from globular clusters was stripped away so long ago it is no longer noticeable. That makes me think they evolved differently. An infalling, young galaxy would be useful to study. Unfortunately, such candidates are hard to find. Even more, unfortunately, none are near enough to study in great detail. The basic physics, however, seem very sound.

[Nereid]

Oh interesting. Well I didn't see a mainstream theory forum so if there's a better place, mods feel free to move this thread.

So moved, from the ATM section to Astronomy.

[tony873004]

I believe all stars in globular clusters are about the same age. Is this true for galactic nuclei?

Do globs need a central black hole to stay together?

How important are binary stars in globs. Some feel that they act as egg beaters, scrambling the stars and pushing them into higher orbits, expanding the cluster and ensuring its longevity.

[Nereid]

IIRC, there was a recent paper showing that at least one globular cluster had two distinct populations of stars (sorted by age).

Galactic nuclei clearly don't have a single age population! However, stars in galactic bulges may be more uniform in age.

[George]

IIRC, there was a recent paper showing that at least one globular cluster had two distinct populations of stars (sorted by age).

This cluster may have three.