Comet c/2023 A3 Tsuchinshan-ATLAS

Oct 2024

过近日点后，紫金山-阿特拉斯彗星与太阳的角距离逐渐减小，并不断地靠近地球，10月12日与地球的距离达到最近，其亮度也有望持续增加，届时，彗星将以更宏伟的姿态出现在人们的视野。

随着紫金山-阿特拉斯彗星的移动，它在天空出现的位置也在变化。10月上旬之前，彗星出现在早上的东方低空；但在10月4日至11日，彗星位于太阳附近不易观测；10月12日以后，彗星将出现在日落后的西方低空，角度不断升高，但是亮度迅速下降。

观测彗星时，可在天气晴朗、大气通透的时候，选择位置高而开阔，光污染小的地方，用相机拍摄或用双筒望远镜观测，也可以尝试将手机固定后长曝光拍摄。由于紫金山-阿特拉斯彗星靠近太阳，使用望远镜观测时一定要注意安全。

Reference

紫金山天文台

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Ephemeris in python, skyfield

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