Abstract: A method is provided for controlling a set of at least two satellites adapted to provide a service used by at least one portion of the set of the said satellites at a given moment, in which, continuously or pseudo-continuously, a mean value of the longitudes of the respective ascending nodes of each satellite is computed, and, for each satellite, a correction of trajectory of the satellite is applied by regulating the longitude of the ascending node on a setpoint equal to said current mean value.

Abstract: The method for lightening the weight of fuel stowed onboard during an interplanetary mission is characterized in that it consists: in launching (10a) a first orbiter spacecraft (1) from the Earth on a first interplanetary trajectory (31, 33) towards a target planet to be explored, in launching (10b) a second orbiter spacecraft (2) from the Earth on a second interplanetary trajectory (32, 34) towards a rendezvous spot (38), the second interplanetary trajectory not comprising any phase of placing in orbit around the target planet, in recovering a load to be transported and in loading it onto the first orbiter spacecraft (1), in returning the first orbiter spacecraft (1) and the load from the target planet to the rendezvous spot (38), in effecting a docking (14) of the two orbiter spacecraft (1, 2), in returning at least the second orbiter spacecraft (2) and the load, from the rendezvous spot (38) to a terrestrial orbit (41).

Abstract: The method for lightening the weight of fuel stowed onboard during an interplanetary mission is characterized in that it consists: in launching (10a) a first orbiter spacecraft (1) from the Earth on a first interplanetary trajectory (31, 33) towards a target planet to be explored, in launching (10b) a second orbiter spacecraft (2) from the Earth on a second interplanetary trajectory (32, 34) towards a rendezvous spot (38), the second interplanetary trajectory not comprising any phase of placing in orbit around the target planet, in recovering a load to be transported and in loading it onto the first orbiter spacecraft (1), in returning the first orbiter spacecraft (1) and the load from the target planet to the rendezvous spot (38), in effecting a docking (14) of the two orbiter spacecraft (1, 2), in returning at least the second orbiter spacecraft (2) and the load, from the rendezvous spot (38) to a terrestrial orbit (41).

Abstract: An attitude control system is disclosed for geostationary satellites including elongate members such as solar generators and/or antennas, in particular deployable members. The system includes gyroscopic actuators for supplying the torque necessary for maintaining the attitude of the satellite when subjected to disturbing forces or torques. The gyroscopic actuators preferably maintain a setpoint attitude during orbit correction phases.

Abstract: A satellite attitude control system includes a programmed processor system which includes a gyroscopic actuator first control stage for changing the attitude of the satellite and a reaction wheel second control stage for assuring that pointing of the satellite is accurate and stable. The method is intended to be used for a satellite including the two control stages indicated above, which it uses selectively for the operations indicated above.