In 2009 Sloan Digital Sky Survey found the galaxy now known as Segue 2, cowering at the edge of the Milky Way. The whole shebang, caboodle, thingy is only about 150,000 times as massive as our sun and only holds around a few thousand stars.
Evan Kirby, University of California, Irvine wants to check that the galaxy is 'real', rather than a globular cluster which would have formed as a tightly bound bundle of stars with the Milky Way.
The general agreement on Segue 2 is that it was formed as a real galaxy, then 'bullied' by us. This is because it has the chemical complexion of a galaxy but is no longer big enough to hold onto the elements that are heavier than iron that are kicked out by supernovae. Such debris would be discarded by globular clusters, but Segue 2 seems to have seen many supernovae and held onto the debris.
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