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Fraser
2004-Oct-20, 05:07 PM
SUMMARY: The Milky Way is a messy eater. When it collides with other galaxies and consumes them, it leaves shredded collections of stars around called dwarf galaxies. Astronomers poring through the data from the Sloan Digital Sky Survey have found what they think could be a new dwarf galaxy. This new object, called Willman 1, is dim: 200 times less luminous than any other nearby dwarf galaxy. Further observations could validate the theory that the Milky Way is surrounded by clumps of dark matter, each of which has a dwarf galaxy in their centre.

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StarLab
2004-Oct-20, 06:05 PM
Wow...you'd think we'd be solving stuff with these kinds of observations, instead it's gettig more and more mysterious.

lswinford
2004-Oct-20, 08:33 PM
One thing amused me, the closing statement about these being part of the "building blocks" of our galaxy, though our already-built galaxy was here and surviving whatever galaxy source or companion they were previously associated with.

The article mentions inquiry into "dark matter" as part of the dynamic. The article mentions that the object is larger or wider than expected. Forgive me if I remember it wrong, but "dark matter" is popularly known for two properties: mass (the supposedly "hidden" mass that some theorists need for expected mass values for the universe) and possibly as a repulsive force (as in driving galaxy groups further apart than would be expected from 'normal' scattering from the original big bang). Might this globular cluster/dwarf galaxy be more scattered and diffuse because of the repulsive forces of the dark matter supposedly discerned in its neighborhood? I wonder if this cluster would expand until the mutual gravitational effects of the cluster are overcome by the gravitational pull of our galaxy, drawing the stars out and down into our disk, assuming, in light of guesses at their old age, that they live so long. What pushes them apart would also push some of them down (relative to our galaxy) and so some of those stars might eventually "rain" upon the arms of our galactic system or be swept into one of our galaxy's arms. An interesting picture to my petty mind.