Abstract: An apparatus for orienting an object mounted on a first plane, for example a radar antenna, with reference to a second plane, for example the deck of a ship. The apparatus includes a stack of three identical, substantially annular housings each of which is provided with an upper surface and a lower surface, these two surfaces not being parallel. Each housing is provided with a drive unit for rotating the upper surface with respect to the lower surface about the housing axis. The drive units are suitable for independently performing the rotations; furthermore control units are provided for controlling the drive units for orienting the object in three degrees of freedom with reference to the second plane.