Horizons in Bianchi universes

There are two ways to introduce horizons in anisotropic spatially homogeneous universes: in the first one the anisotropy appears directly in the definitions, whereas in the second way a "mean horizon" is defined, with a consequent loss of information on the direction. In this work we give the expression of horizons in all nine Bianchi types, using the Misner parametrization of metric. We examine, also, some examples regarding the Bianchi type I; in each case the achieved expressions are compared with the correspondent mean horizons.