Here's why:

* Scientific Method: Cosmology uses the scientific method to study the universe. It makes observations, formulates hypotheses, and tests those hypotheses through experiments and further observations.

* Empirical Evidence: Cosmological theories are based on empirical evidence, like observations of distant galaxies, the cosmic microwave background radiation, and the distribution of matter in the universe.

* Mathematical Models: Cosmology relies heavily on mathematical models to describe and predict the behavior of the universe. These models are constantly refined and updated as new observations become available.

While cosmology deals with vast and complex topics, it's still firmly rooted in the scientific method and relies on observational data to support its theories.