Effects of Uncertainties in the Atmospheric Density on the Probability of Collision Between Space Objects
Effects of Uncertainties in the Atmospheric Density on the Probability of Collision Between Space Objects
复制标题
大气密度的不确定性对空间物体碰撞概率的影响
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
J. Getchius
中科院分区：
文献类型：
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作者：
C. Bussy‐Virat;A. Ridley;J. Getchius
环绕地球轨道的物体数量迅速增加，对运行中的航天器和宇航员构成严重威胁。为了有效避免碰撞，使命操作员需要评估卫星与轨道可能接近其轨迹的任何其他物体之间碰撞的风险。几种算法预测碰撞的概率，但有限制，损害预测的准确性。一个重要的限制是，在大气密度的不确定性通常不考虑在传播的协方差矩阵从当前历元到最近的方法的时间。100公里至700公里之间的大气层受到太阳和磁层活动的强烈驱动。因此，驾驶员的不确定性直接与中性密度的不确定性有关，因此也与阻力加速度的不确定性有关。这就为预测低地球轨道，特别是确定碰撞概率提供了重要的考虑。这项研究表明，大气密度的不确定性如何会造成碰撞概率的显著差异，并提出了一种算法，考虑到这些不确定性，以更准确地评估碰撞风险。作为一个例子，说明了磁暴对碰撞概率的影响。
The rapid increase of the number of objects in orbit around the Earth poses a serious threat to operational spacecraft and astronauts. In order to effectively avoid collisions, mission operators need to assess the risk of collision between the satellite and any other object whose orbit is likely to approach its trajectory. Several algorithms predict the probability of collision but have limitations that impair the accuracy of the prediction. An important limitation is that uncertainties in the atmospheric density are usually not taken into account in the propagation of the covariance matrix from current epoch to closest approach time. The atmosphere between 100 km and 700 km is strongly driven by solar and magnetospheric activity. Therefore, uncertainties in the drivers directly relate to uncertainties in the neutral density, hence in the drag acceleration. This results in important considerations for the prediction of Low Earth Orbits, especially for the determination of the probability of collision. This study shows how uncertainties in the atmospheric density can cause significant differences in the probability of collision and presents an algorithm that takes these uncertainties into account to more accurately assess the risk of collision. As an example, the effects of a geomagnetic storm on the probability of collision are illustrated.