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pluto2
12-10-08, 07:03 AM
Are most galaxies in the universe dwarf galaxies?

I read that there are 125-130 billion galaxies in the observable universe but do we know how many of these are dwarf galaxies?

Enmos
12-10-08, 07:09 AM
Are most galaxies in the universe dwarf galaxies?

I read that there are 125-130 billion galaxies in the observable universe but do we know how many of these are dwarf galaxies?

If most of them are 'dwarf galaxies', wouldn't that make them regular galaxies ?
Sorry if I'm missing something.

cosmictraveler
12-10-08, 07:34 AM
There are also:

Hobbit galaxies

The recently coined term, hobbit galaxy has been used to describe galaxies smaller and dimmer than dwarf galaxies.


Ultra Compact Dwarfs

Ultra Compact Dwarf galaxies (UCD) are a recently discovered class of very compact galaxies with very high stellar population counts. They are thought to be on the order of 200 light years across, with a hundred million stars. It is theorized that these are the cores of nucleated dwarf elliptical galaxies, that have been stripped of gas and outlying stars by tidal interactions, travelling through the hearts of rich clusters. UCDs have been found in the Virgo Cluster, Fornax Cluster, Abell 1689, amongst other clusters.


http://en.wikipedia.org/wiki/Dwarf_galaxy#Dwarf_galaxies

pluto2
12-10-08, 12:20 PM
If most of them are 'dwarf galaxies', wouldn't that make them regular galaxies ?
Sorry if I'm missing something.

Nice point. So are most galaxies in the universe bigger or smaller than the Milky Way (our galaxy)?

I read somewhere that most galaxies are actually smaller than the Milky Way. Here's the site:

http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/001205a.html