A computer system of the present invention comprises a processor unit, and is configured to be capable of communicating with a user device operated by a first user and a satellite. The satellite includes a religious object and an information providing means for providing information associated with the religious object. The processor unit is configured to execute at least the following: acquiring location data indicating a location on Earth of the first user; acquiring bearing data indicating a bearing; calculating, on the basis of the location data and the bearing data, a time period in which the satellite is located in a predetermined space extending toward the bearing from the location on Earth of the first user; and providing the user device with information associated with the religious object provided by the information providing means of the satellite only during the time period.

A computer system of the present invention comprises a processor unit, and is configured to be capable of communicating with a user device operated by a first user and a satellite. The satellite includes a religious object and an information providing means for providing information associated with the religious object. The processor unit is configured to execute at least the following: acquiring location data indicating a location on Earth of the first user; acquiring bearing data indicating a bearing; calculating, on the basis of the location data and the bearing data, a time period in which the satellite is located in a predetermined space extending toward the bearing from the location on Earth of the first user; and providing the user device with information associated with the religious object provided by the information providing means of the satellite only during the time period.

Instead of users (e.g., independent owners/operators of different satellites) having to calculate orbit determination for each satellite themselves, an orbit determination service automatically calculates the orbit determination (OD) based on a user request. The calculated OD can then be used by a satellite ground station service to determine appropriate orientations for a ground station antenna in order to communicate with the satellite. In some embodiments, the OD service uses information from the calculations of ODs for multiple satellites and users to update a model used in the OD calculation, for example, to provide a more accurate model for Earth's atmosphere to be applied in subsequent OD calculations. In some embodiments, the OD service uses a user-provided computer-aided drawing (CAD) file of the satellite to produce or tune models specific to the satellite, for example, to generate more accurate models for solar radiation pressure and ballistic drag.

Instead of users (e.g., independent owners/operators of different satellites) having to calculate orbit determination for each satellite themselves, an orbit determination service automatically calculates the orbit determination (OD) based on a user request. The calculated OD can then be used by a satellite ground station service to determine appropriate orientations for a ground station antenna in order to communicate with the satellite. In some embodiments, the OD service uses information from the calculations of ODs for multiple satellites and users to update a model used in the OD calculation, for example, to provide a more accurate model for Earth's atmosphere to be applied in subsequent OD calculations. In some embodiments, the OD service uses a user-provided computer-aided drawing (CAD) file of the satellite to produce or tune models specific to the satellite, for example, to generate more accurate models for solar radiation pressure and ballistic drag.

A method for re-entry prediction of an uncontrolled artificial space object includes: calculating an average semi-major axis and an argument of latitude by inputting two-line elements or osculating elements of an artificial space object at two different time points; calculating an average semi-major axis, argument of latitude, and atmospheric drag at a second time point; estimating an optimum drag scale factor while changing the drag scale factor; predicting the time and place of re-entry of an artificial space object into the atmosphere by applying the estimated drag scale factor. Here, orbit prediction is performed by using a Cowell's high-precision orbital propagator using numerical integration from the second time point to a re-entry time point.

A method for re-entry prediction of an uncontrolled artificial space object includes: calculating an average semi-major axis and an argument of latitude by inputting two-line elements or osculating elements of an artificial space object at two different time points; calculating an average semi-major axis, argument of latitude, and atmospheric drag at a second time point; estimating an optimum drag scale factor while changing the drag scale factor; predicting the time and place of re-entry of an artificial space object into the atmosphere by applying the estimated drag scale factor. Here, orbit prediction is performed by using a Cowell's high-precision orbital propagator using numerical integration from the second time point to a re-entry time point.

A method of determining a precise orbit of a satellite through estimation of a parallactic refraction scale factor is proposed, the method includes inputting an initial estimate including initial orbit information of a satellite with respect to an observation epoch and the parallactic refraction scale factor; performing orbit propagation using a high-precision orbit propagator by applying a dynamics model; performing observer-centered satellite optical observation modeling including the parallactic refraction scale factor; calculating an observation residual between actual optical observation data and observation data calculated via the observation modeling reflecting the parallactic refraction; and precisely determining the orbit of the satellite by estimating the parallactic refraction scale factor and a satellite state vector using a batch least square estimation algorithm.

A method of determining a precise orbit of a satellite through estimation of a parallactic refraction scale factor is proposed, the method includes inputting an initial estimate including initial orbit information of a satellite with respect to an observation epoch and the parallactic refraction scale factor; performing orbit propagation using a high-precision orbit propagator by applying a dynamics model; performing observer-centered satellite optical observation modeling including the parallactic refraction scale factor; calculating an observation residual between actual optical observation data and observation data calculated via the observation modeling reflecting the parallactic refraction; and precisely determining the orbit of the satellite by estimating the parallactic refraction scale factor and a satellite state vector using a batch least square estimation algorithm.

In a space traffic management system (500), space traffic management devices (100) individually mounted in a plurality of mega-constellation business devices and in a debris removal business device (45) are connected to each other via a communication line (200). The debris removal device (45) performs Active Debris Removal (ADR) against debris formed by a satellite managed by a first mega-constellation business operator. The debris removal device (45) acquires real-time high-accuracy orbital information of a satellite group of a second mega-constellation business operator in a timeframe in which a debris removal satellite, during orbital descent, passes through an orbital altitude region where the satellite group of the second mega-constellation flies, the debris removal satellite passing through the satellite group while ensuring flight safety.

A projection unit (12) of an interference power estimation device (1) projects an orbit of a satellite onto a map representing a ground surface. A range acquisition unit (13) determines a plurality of ranges on the map so that the projected orbit is included in the ranges. An altitude calculation unit (14) calculates an altitude of the orbit of the satellite in each of the ranges. A range interference calculation unit (16) calculates, for each of the ranges, an interference power between the satellite at a position determined by a latitude and a longitude of the range and the altitude calculated for the range and a radio station installed on the ground surface. An estimation result calculation unit (17) selects, as an estimation result, a maximum value among the interference powers calculated for each of the ranges.