The propagation of linear magnetosonic waves in a homogeneous collisionless magnetized plasma composed of two positive ions and electrons is investigated. The dispersion

relation is derived using linear analysis to describe the dynamics of the behavior of the

magnetosonic wave. There are two propagating modes for every ion species. Magnetized

mode at low wavenumbers and ion cyclotron mode at higher wavenumbers. Electrons

also have two propagating modes: a Whistler mode at low wavenumbers and an electron

cyclotron mode at higher wavenumbers. Also, a field mode is found to propagate at very

high frequencies. The propagation of these localized structures against variations in the

magnetic field and the ion number densities has been discussed. Variations in the magnetic field affect Alfven mode, Whistler mode, and the ion cyclotron modes. While the

variations of number density influence the Alfven mode, Whistler mode, and field mode.

This model is applied on the magnetosonic waves propagating in the Marian magnetosphere.