Abstract: The attitude of a satellite placed on a non-heliosynchronous earth orbit in a plane that is inclined relative to the equatorial plane of the earth is controlled for efficient use of solar panels and radiators. The satellite has a structure, solar panels apt to be rotated with respect to the structure rotation and two opposed radiators each fixed on one of two opposed faces of the satellite structure which are orthogonal to the rotation axis. One of the radiators has greater emissivity than the other. A yaw axis bound to the structure satellite and orthogonal to rotation axis is aimed towards the earth. The solar panels of the satellite are maintained in an optimum orientation relative to the sun by rotating them. At least during periods of each year when an angle .beta.

Abstract: An electronically scanned antenna comprising an array (11) of elementary sources, an energy-focusing reflector (10), and feed and control electronics, with the array (11) being situated in the focal zone of the reflector, and in which elementary sources that are not used simultaneously are grouped together in classes (Ci) in which only one source can be active at a time, with all of the sources in each class (Ci) being interconnected by a passive combiner (40) for that class. The invention is applicable in particular to space telecommunications.