空间目标光度测量的消光修正拟合

Extinction correction fitting for photometric measurement of space targets

为了提高光度测量的精度进而提高反演空间目标的姿态、形状等特性的准确率,提出了消光修正拟合的光度测量方法。传统的光度测量是利用一些已知星等恒星的灰度值计算零等星灰度值,然后再通过待测目标的灰度值计算出待测目标的星等值,在此过程中加入经典大气消光模型所带来的影响。先是利用实测数据对光度测量计算过程中的消光修正进行拟合,充分考虑实际测量时大气消光所带来的影响,获取更符合实际情况的光度测量数据。然后,在零等星灰度标定的过程中采取迭代的方法计算零等星灰度的均值,降低大气不稳定所带来的异常数据对于测量结果的影响。实验结果表明:改进优化后光度测量方法的精度可以达到0.11个星等。相对于以往的光度测量方法测量精度更高,测量结果可以更好地应用于后续的反演工作。

To improve the accuracy of photometric measurements and the attitude and shape inversion of space targets,a photometric measurement method entailing extinction coefficient fitting was proposed based on existing measurement methods. In conventional photometric measurement methods,the gray value corresponding to a"0"magnitude was calculated using the gray values of stars whose magnitude was known;then,the magnitude of targets was calculated using their gray values while considering the effect of atmospheric extinction. In this study,more accurate photometric measurement data was obtained using the extinction-correction fitting method,based on actual measured data. Then,to reduce the impact of anomalous data due to atmospheric instabilities,the method of obtaining the iteration mean was used for calibrating the gray value corresponding to 0 magnitude. Experimental results indicate that the error of the improved photometric measurement method is approximately 0. 11 magnitude. Compared with previous photometric measurement methods,this improved photometric measurement method has a higher degree of precision,and the measured results can be better applied to subsequent inversion work.