According to scientists a small dark galaxy is colliding with our galaxy. The mass was discovered last year and named 'Smith's Cloud'. At the time it was estimated that it has a mass equal to around one million of our suns.
More recent calculations by University of Sydney scientists suggest that this is the second time it has collided with the Milky way. Its survival the first time around suggests that it has 100 times the originally estimated mass, and is a galaxy in its own right.
According to the UC Berkeley's Leo Blitz there are thought to be around 1,000 dwarf galaxies in the vicinity of our larger galaxy but to date only a few have been found. Some of the ones yet to be found may be dark galaxies.
