Abstract: A method for observing a region of the Earth's surface, called region of interest, implementing a plurality of satellites spaced apart along at least one non-stationary orbit, the method comprises: the acquisition, by at least two of the satellites, during a same passage over the region of interest and in successive acquisition periods, of a plurality of images of the Earth's surface, called partial images, each covering a portion of the region of interest; and the obtaining of an image covering all of the region of interest by the merging of at least two partial images, exhibiting a predefined time shift between their acquisition periods, for each of the at least two satellites. A satellite system for observing a region of the Earth's surface for the implementation of such a method, and ground segment belonging to such a system is provided.

Abstract: A relay platform for communicating telemetry data from one or more moving observation satellite(s) to the ground is provided. The relay platform for communicating from a space observation system, installed on board an aircraft moving above the clouds, comprises a first reception interface for demodulating telemetry data from at least one moving observation satellite, a second transmission interface for modulating and transmitting the data received to at least one destination ground station. The relay platform comprises a first descending two-level decryption/encryption chain for the telemetry data returned from at least one moving observation satellite(s) to the destination ground station(s).

Abstract: A relay platform for communicating telemetry data from one or more moving observation satellite(s) to the ground is provided. The relay platform for communicating from a space observation system, installed on board an aircraft moving above the clouds, comprises a first reception interface for demodulating telemetry data from at least one moving observation satellite, a second transmission interface for modulating and transmitting the data received to at least one destination ground station. The relay platform comprises a first descending two-level decryption/encryption chain for the telemetry data returned from at least one moving observation satellite(s) to the destination ground station(s).

Abstract: A space system comprises two main satellites each describing a distinct elliptical orbit around the Earth, each of the two orbits being such that the space system makes it possible to provide a permanent or continuous service over at most a terrestrial zone comprising a polar cap and a region of different latitude over an interval of longitudes.

Abstract: A method for observing a region of the Earth's surface, called region of interest, implementing a plurality of satellites spaced apart along at least one non-stationary orbit, the method comprises: the acquisition, by at least two of the satellites, during a same passage over the region of interest and in successive acquisition periods, of a plurality of images of the Earth's surface, called partial images, each covering a portion of the region of interest; and the obtaining of an image covering all of the region of interest by the merging of at least two partial images, exhibiting a predefined time shift between their acquisition periods, for each of the at least two satellites. A satellite system for observing a region of the Earth's surface for the implementation of such a method, and ground segment belonging to such a system is provided.

Abstract: A method is provided for controlling a set of at least two satellites, designed to provide a service on a geostationary orbit, rendering said service on a non-geostationary orbit, in which means involved in the performance of said service, installed on board a satellite, are deactivated when the sun can damage it, and means involved in the performance of said service installed on board another satellite of the set are activated, when this is necessary to the continuity of the service.

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: A method for capturing a container of planet ground samples moving in space by a probe also moving in space includes, when the probe is on the orbit of the container, at a distance of a few meters therefrom and the receiving face of the probe is oriented toward the container, generating, on board the probe, a first controlled magnetic field to reduce the angular speeds of the container and orient it in a preferred direction for the capture, and, when these speeds have become negligible and the probe is positioned in the correct orientation, while the probe is being brought closer to the container, a process of attraction of the container relative to the probe is begun using another field whose field lines converge toward the capture zone of the probe.

Abstract: A method and a device are provided for the optimization of the mass of a satellite. The method includes: a step of calculation of an elliptical second orbit obtained by rotation of a first orbit about an axis connecting the periapsis and the apoapsis, the elliptical second orbit being associated with a second maximum eclipse duration less than a first maximum eclipse duration; a step of determination of a maneuver enabling the satellite to move to the second orbit; and a step of calculation of a second battery mass making it possible to maintain the satellite in operation during the second maximum eclipse duration and of calculation of a mass of fuel necessary to effect the maneuver.

Abstract: A method and a device is provided for the optimization of the mass of a satellite. The method includes: a step of calculation of an elliptical second orbit obtained by rotation of a first orbit about an axis connecting the periapsis and the apoapsis, the elliptical second orbit being associated with a second maximum eclipse duration less than a first maximum eclipse duration; a step of determination of a manoeuvre enabling the satellite to move to the second orbit; and a step of calculation of a second battery mass making it possible to maintain the satellite in operation during the second maximum eclipse duration and of calculation of a mass of fuel necessary to effect the manoeuvre.

Abstract: A method for capturing a container of planet ground samples moving in space by a probe also moving in space includes, when the probe is on the orbit of the container, at a distance of a few meters therefrom and the receiving face of the probe is oriented toward the container, generating, on board the probe, a first controlled magnetic field to reduce the angular speeds of the container and orient it in a preferred direction for the capture, and, when these speeds have become negligible and the probe is positioned in the correct orientation, while the probe is being brought closer to the container, a process of attraction of the container relative to the probe is begun using another field whose field lines converge toward the capture zone of the probe.

Abstract: A satellite comprises a main body and, in orbit, at least one free object floating in space including a portion of the payload transferred from the main body. The free object is restricted to a precise position and attitude relative to the main body. An electromagnetic force and an electromagnetic torque are produced for controlling the position and the attitude of the free object in accordance with a master-slave relationship.

Abstract: The present invention relates to an aircraft and to a method of getting the aircraft onto station. According to the invention, said aircraft (1) includes propulsion means (2) capable only of enabling said aircraft (1) to move and to orient itself at high altitude, and said aircraft (1) is taken to its station in the high atmosphere, in particular in the stratosphere, by means of an independent transporter (3).

Abstract: A satellite comprises a main body and, in orbit, at least one free object floating in space including a portion of the payload transferred from the main body. The free object is restricted to a precise position and attitude relative to the main body.

Abstract: A method and apparatus to perform the observation and imaging from a space vehicle by scanning of a celestial body with reference to a scanning axis, forming successively two signals corresponding to the scanning in a given directional series of a line or band including ground area, detecting in each of these signals a characteristic transition representative of a given characteristic point of this line or band of ground, reading the relative position of these transitions in these signals, and determining an angular velocity of the space vehicle from any divergence between these relative positions while taking into account the time interval separating the instants where each of these transitions appeared in the aforementioned formed signals.