This suggests that some of its DM is in the disk, perhaps in a molecular form. These properties are discussed more fully in Meurer et al. Here is the dimensionless Hubble constant used in the individual studies. Circles represent fits to dI and spiral galaxies, while the squares represent the fits to NGC 2915 presented here. Solid symbols show isothermal sphere halo model fits, hollow symbols shows analytic halo model fits.
Connected points represent different halo models fit to the same object.
This suggests BCDs as a class have fundamental structural differences from dI and spiral galaxies, and NGC 2915 is only odd because it is the first BCD examined in such detail. It is therefore important to do further detailed HI studies of BCDs. There are two issues in particular that need to be addressed. Firstly, if the abnormally high of NGC 2915 is common to BCDs, then transformations between BCD and dI morphologies could not be accomplished by turning starbursts on and off. Fundamental structural changes to the DM distributions would also have to occur, and this seems hardly likely.