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Qinghai-Tibet plateau is one of the increasingly important parts of Chinese Mainland. After military tension at the boundary between China and India appeared a few years ago, China is focusing on such tasks as remote sensing of Qinghai-Tibet plateau. Qinghai-Tibet plateau is too large to collect basic dataset of meteorology, greenery, and hydrology by manual means. Space-based technique can meet such an requirement. Such payloads onboard spacecraft as lidar, radiometer, radar can provide a good solution to effectively collect dataset for a particular area of interest. With the deployment of comprehensive survey of Qinghai-Tibet plateau by China, the feasibilities assessment of implementing space project to monitor the Qinghai-Tibet plateau are impending. How to choose the most proper orbit is one of the tasks of feasibilities assessment. Herein, three sets of orbits are simulated and assessed. In case 1, a circular orbit with 250 kilometers in altitude is analyzed, and the operation orbit is sun-synchronous. According to relative simulations, orbital altitude damping rate is 10.2 kilometers per day. In order to keep the stable orbit altitude or offset the orbit altitude damping, 558 kilograms of fuel should be needed per year; 1117 kilograms of fuel should be needed to keep a stable orbit every two years. In case 2, an elliptic orbit with perigee altitude of 250km and apogee altitude of 500km is considered. Based on relative simulations, orbital altitude damping rate is 2.461 kilometers per day. In order to keep the stable orbit altitude or offset the orbit altitude damping, 130 kilograms of fuel should be needed per year; 261 kilograms of fuel should be needed to keep a stable orbit every two years. In case 3, an elliptic orbit with perigee altitude of 250km and apogee altitude of 600km is considered. Based on relative simulations, orbital altitude damping rate is 1.67 kilometers per day. In order to keep the stable orbit altitude or offset the orbit altitude damping, 87.6 kilograms of fuel should be needed per year; 175.2 kilograms of fuel should be needed to keep a stable orbit every two years. During the simulation and assessment, the ratio of area to mass of the spacecraft in question is assumed to be 0.01 square meters per kilograms; and the mass of the spacecraft is set to be 500 kilograms. As a result of trade-off between economy and payload priority of observation advantages, the case 3 is preferred to work as the operation orbit. In such an orbit, the spacecraft will contribute more efficiently to the comprehensive surveying of Qinghai-Tibet plateau.
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