Dynamic Masses for Coma
• Merritt (1987) analysis:
– Assuming constant M/L ratio, then mass is 1.79
x 1015h-1 solar masses, and M/L is 350 h-1 in
solar units (think about that!).
– Typical M/L for ellipticals is 15 in solar units.
– Differ by a factor of 20
• Why should the dark matter have the same
distribution as the light?
• Why should the velocities even be isotropic?