紫金山–阿特拉斯彗星不寻常的彗尾

2024年11月11日

The Unusual Tails of Comet Tsuchinshan-Atlas
Image Credit & Copyright: Bray Falls

Explanation: What created an unusual dark streak in Comet Tsuchinshan-Atlas’s tail? Some images of the bright comet during mid-October not only caught its impressively long tail and its thin anti-tail, but a rather unexpected feature: a dark streak in the long tail. The reason for the dark streak is currently unclear and a topic of some debate. Possible reasons include a plume of dark dust, different parts of the bright tail being unusually superposed, and a shadow of a dense part of the coma on smaller dust particles. The streak is visible in the featured image taken on October 14 from Texas, USA. To help future analyses, if you have taken a good image of the comet that clearly shows this dark streak, please send it in to APOD. Comet Tsuchinshan–ATLAS has now faded considerably and is returning to the outer Solar System.

Gallery: Comet Tsuchinshan-ATLAS in 2024
Tomorrow’s picture: cosmic crescent

紫金山–阿特拉斯彗星不寻常的彗尾
影像提供与处理: Bray Falls

说明: 紫金山–阿特拉斯彗星彗尾的不寻常暗色条纹是怎么来的？在今年10月中旬拍摄的此明亮彗星之部分影像里，不仅记录了它令人印象深刻的颀长彗尾及细薄的反彗尾，还意外显示它的彗尾里有道暗色条纹。这条道暗色条纹的成因，目前不明而且难有定论。可能的成因包括：突然出现一股暗色的尘埃 羽流，明亮彗尾的不同区域发生异常的重叠，彗发致密区投射的影子，或者是太阳风对小尘埃颗粒的外推压力降低等。这条暗色条纹，也清楚的出现在这幅10月14日摄于美国德州的主题影像里。如果你拍下可清楚显示这道暗色条纹的彗星照片，并有意为未来的分析提供助力，请寄送给天文·每日一图（APOD）。目前紫金山–阿特拉斯彗星已在返回太阳系外围的途中，而且其亮度已大幅降低。

画廊: 2024年的紫金山–阿特拉斯彗星
明日的图片: cosmic crescent