Are UCD's the MACHO's we've been lookin for?

[Thales]

A recent study conducted by Australian Astronomer Micheal Drinkwater at Siding Springs Observatory in NSW, has reveiled an unexpected abundance of Ultra Compact Dwarf Galxies (UCD's). These galaxies are tiny and had previously been misconcieved as stars in our own galaxy due to their minute size. However a detailed Spectroscopic analysis of the Fornax Cluster has shown that these objects are satellite galaxies, orbiting the Milky Way in intergalactic space.

 

One of the suprising conclusions of the study has been that these UCD's may infact be more abundant than the more commonly known spiral galaxies and while they do not account for all the missing mass(each only contains a few million solar masses) in the Dark Matter equation, they may add significantly to the known amount of luminous matter in the universe. They are also considered to be important as the current leading theory of galactic formation requires that our galaxy formed from an accumulation of smaller galaxies which were, until recently, unaccounted for.

[RICHARDBATTY]

From what I've heard its a mixture of dark and normal matter and is colliding with our galaxy. They say it must contain dark matter as it has held up to gravitational tidal forces better than it could with only the visible portion. Hope its not a mini hole As it is it seems you may be right. If we only just found ours what chance have we of finding them futher afield.

[Thales]

I think your confusing a definition of dark matter with the process by which we understand its presence (ie the radial velocity curves of galaxies).

 

What is this mini hole you speak of?

[RICHARDBATTY]

I think your confusing a definition of dark matter with the process by which we understand its presence (ie the radial velocity curves of galaxies).

 

What is this mini hole you speak of?

A micro black hole. I meant that what was thought to be a star, contained visible matter and dark matter and could therefore contain more mass than just the star. If we had difficulty finding this out in our own galaxy, universaly there could be a lot of the dark matter unaccounted for