There are two models that explain the rotation curves of galaxies: dark matter, which gives the missing contribution to the gravitational potential of the standard theory of gravity, and modified theories of gravity, according to which the gravitational potential is created by ordinary visible mass. Both models have some disadvantages. The article offers a new look at the problem of galactic rotation curves. The author suggests that the moment of inertia creates an additional gravitational potential along with the mass. The numerical simulation carried out on the example of fourteen galaxies confirms the validity of such an assumption. This approach makes it possible to explain the constancy of gas velocities outside the galactic disk without involving the hypothesis of the existence of dark matter. At the same time, the proposed approach lacks the disadvantages of modified theories of gravity, where the gravitational potential is created only by the mass of visible matter.