There are multiple independent observations pointing toward dark matter:
1. Galaxy rotation curves.
2. Galaxy cluster mass measurements from gravitational lenses and infrared.
3. Cosmic Microwave Background models (mass measurements from inhomogeneities that correspond to acoustic waves, for eg).
MOND only explains 1.
Dark matter accounts for all 3. Only catch is that it hasnt been directly observed.
1. Galaxy rotation curves. 2. Galaxy cluster mass measurements from gravitational lenses and infrared. 3. Cosmic Microwave Background models (mass measurements from inhomogeneities that correspond to acoustic waves, for eg).
MOND only explains 1.
Dark matter accounts for all 3. Only catch is that it hasnt been directly observed.