An object is to notify an appropriate intrusion alert by determining whether debris will intrude into an orbit area of a satellite constellation. A passage determination unit (110) determines whether debris will pass through a satellite orbit area, based on satellite orbit forecast information in which a forecast value of an orbit of a satellite is set and debris orbit forecast information in which a forecast value of an orbit of debris is set. When it is determined that debris will pass through the satellite orbit area, an alert generation unit (120) generates an intrusion alert (111) including a predicted time, predicted location coordinates, and predicted velocity vector information that relate to passage of the debris. An alert notification unit (130) notifies the intrusion alert (111) to a management business device (40) used by a management business operator that manages a satellite that flies in the satellite orbit area.

A tethered uni-rotor network of satellite vehicles, is made up of a central hub with multiple tethers radiating outward in a hub-and-spoke arrangement. Each tether attaches to a satellite vehicle; each having lifting airfoil surfaces, stabilizers, control surfaces, fuselages, and propulsion systems. The entire system operates in a persistent state of rotation, driven by the propulsion units on each satellite vehicle, so the airfoils generate lift which supports each satellite vehicle and a distributed portion of the weight of the central hub. As the system rotates, centrifugal forces pull each satellite vehicle outwards, which keeps each tether taught and applies tension across each of the lifting surfaces, thereby alleviating the bending moment common to fixed-wing aircraft. This approach reduces the weight within the structural members, utilizes higher aspect ratio wings to reduce induced drag, and employs thin-thickness high-camber airfoil profiles which achieve higher lift-to-drag ratios than standard practice.

A method for providing thermal balance of spacecraft electronics is provided. The spacecraft includes two or more electronic units wherein each electronic unit is capable of performing the same spacecraft operational task. The method for balancing the temperature of spacecraft electronics further includes providing each of the two or more electronic units with a temperature sensor for determining the temperature of that electronics unit. The electronic units and their respective temperature sensors are connected to a controller. In the event that the controller determines that the temperature of an activated first electronics unit has reached or exceeded a predetermined threshold, and the controller has determined that the temperature of a second deactivated electronics unit is below a predetermined threshold, the controller automatically deactivates the first electronics unit and activates the second electronics unit to perform the task previously being performed by the first electronics unit. This process continues automatically.

Satellites having autonomously deployable solar arrays are disclosed. A disclosed example satellite includes a solar array, a sensor to detect that the satellite has exited a launch vehicle, a processor to, based on the satellite exiting the launch vehicle, enable release of magnets or locks of an array, a release controller to control the release of the magnets or the locks of the array based on a release sequence to autonomously deploy the solar array, and a sequence analyzer to adapt the release sequence during execution of the release sequence, wherein adapting the release sequence includes changing an order in which the magnets or the locks of the array are released based on a degree to which the solar array is unfolded.

In an example, a method for deorbiting a spacecraft is described. The method includes selecting a target landing site for deorbiting the spacecraft. The method includes determining a range target and a velocity target for reaching a predicted atmospheric entry location. The method includes determining a back-propagated orbit state estimate of the spacecraft. The method includes comparing the back-propagated orbit state estimate to a known orbit state of the spacecraft to determine that the back-propagated orbit state estimate has converged with the known orbit state. The method includes calculating based on determining that the back-propagated orbit state estimate has converged with the known orbit state, (a) an estimated time of ignition for a propulsion system of the spacecraft and (b) an estimated burn velocity vector of the propulsion system using the range target and the velocity target. The method includes performing a burn pulse by the propulsion system.

In an example, a method for deorbiting a spacecraft is described. The method includes selecting a target landing site for deorbiting the spacecraft. The method includes determining a range target and a velocity target for reaching a predicted atmospheric entry location. The method includes determining a back-propagated orbit state estimate of the spacecraft. The method includes comparing the back-propagated orbit state estimate to a known orbit state of the spacecraft to determine that the back-propagated orbit state estimate has converged with the known orbit state. The method includes calculating based on determining that the back-propagated orbit state estimate has converged with the known orbit state, (a) an estimated time of ignition for a propulsion system of the spacecraft and (b) an estimated burn velocity vector of the propulsion system using the range target and the velocity target. The method includes performing a burn pulse by the propulsion system.

[Object] To provide a sheet-like structure capable of highly accurately estimating a sheet-like shape.

[Solving Means] A sheet-like structure includes a sheet-like member and a plurality of detection sensors. The sheet-like member extends along an in-plane direction orthogonal to a thickness direction and receives light incident on the sheet-like member. The plurality of detection sensors are dispersedly arranged on the sheet-like member along the in-plane direction and are for detecting an incident angle of the light with respect to the sheet-like member at each arrangement position of the plurality of detection sensors.

An orbit analysis unit (431) of a collision avoidance assistance business device analyzes an orbit of a specific space object. When it is foreseen that the specific space object will intrude into an orbital altitude region where a satellite group of a satellite constellation flies, a notification unit (432) of the collision avoidance assistance business device notifies a satellite constellation business operator of an intrusion alert and non-public orbit information of the specific space object via a communication line that is kept secret. A collision analysis unit (411) of a satellite constellation business device analyzes a collision between the specific space object and an individual satellite in the satellite group of the satellite constellation. A countermeasure planning unit (412) of the satellite constellation business device plans a collision avoidance countermeasure when a collision is foreseen.

A space information recorder (100) includes two or more categories of a category, acquired from a mega-constellation business device, of different constellations formed at nearby altitudes by the same business operator, a category of a satellite group of each constellation that flies at the same nominal altitude and cooperatively realizes the same mission, a category of orbital planes, a category of each orbital plane of the orbital planes, and a category of an individual satellite. The space information recorder (100) includes information on upper and lower limit values of an orbital altitude or on a nominal altitude and an altitude fluctuation width for each category.

A space information recorder (100) includes two or more categories of a category, acquired from a mega-constellation business device, of different constellations formed at nearby altitudes by the same business operator, a category of a satellite group of each constellation that flies at the same nominal altitude and cooperatively realizes the same mission, a category of orbital planes, a category of each orbital plane of the orbital planes, and a category of an individual satellite. The space information recorder (100) includes information on upper and lower limit values of an orbital altitude or on a nominal altitude and an altitude fluctuation width for each category.