>the galaxy it’s about the same size Milky Way but has less than 0.5% of its stars and much less than that when it comes to overall mass. What's the mechanism

>the galaxy it’s about the same size Milky Way but has less than 0.5% of its stars and much less than that when it comes to overall mass. What's the mechanism behind the formation of such a sparsely populated galaxy? Was there just way less gas in that region of space for stars to form in the first place? How is there even enough gravity to bind those stars into a galaxy rather than just a forming a series of rogue stars that move independently of one another?