2024年最值得期待的彗星C/2023 A3（Tsuchinshan-ATLAS）12日最接近地球。当日，它将在傍晚的天空现身；如果爆发，亮度有可能还会增加，可以在日落后的西边天空凭肉眼寻找到它。
这颗彗星由中国天文台名字命名——紫金山-阿特拉斯彗星（国际编号C/2023 A3），于2023年1月9日被中国科学院紫金山天文台近地天体望远镜首次观测到，是一颗带有黄色彗尾的彗星。值得关注的是，该彗星的轨道是一个特殊的椭圆形，每6万多年才有一次观测机会，非常值得期待。
中国科学院紫金山天文台科普主管王科超介绍说，对北半球而言，10月12日该彗星将在日落后不久的西方低空出现，位于处女座，但肉眼观测时间很短，大约只有10到20分钟的窗口期。接下来几天，将迎来最佳观测期，日落后的大约1小时里可在西方天空看到它。
The most anticipated comet of 2024, C/2023 A3 (Tsuchinshan-ATLAS) can be observed by the naked eye in the western sky after sunset in the Northern Hemisphere, according to researchers.
"Actually, the comet reached its peak brightness on Oct 4, but it was too close to the sun for humans to see with the naked eye," explained by Wang Kechao from Purple Mountain Observatory, Chinese Academy of Science.
▲ The comet C/2023 A3 (Tsuchinshan-ATLAS), with a yellow tail. Photo/VCGThe comet C/2023 A3 (Tsuchinshan-ATLAS), with a yellow tail, is firstly discovered by the Purple Mountain Observatory, Chinese Academy of Sciences in 2023. Its intense brightness has brought it to the attention of the experts and the public globally.On Saturday, the comet will make its closest approach to Earth. In the Northern Hemisphere, the comet will appear low in the west shortly after sunset and will be visible for about 10 to 20 minutes.In the following days after this, the comet is expected to be seen longer and more easily, and it is predicted that the comet will start to lose visibility in November, according to Wang.
▲ C/2023 A3（紫金山-阿特拉斯）彗星穿过天空的路径 图源：中国教育报
This celestial spectacle also provides an opportunity of continuous observation for researchers, to explore more material composition and activity evolution of comets.According to astronomers' calculations, this is a comet in a near-parabolic elliptical and retrograde orbit, which means it orbits the Sun in the opposite direction of the sun's rotation (from west to east) and takes more than 61,000 years to travel around the Sun.
