天鵝、阿特拉斯和火星
A SWAN, an ATLAS, and Mars
來源：Adam Block｜發表日期：2025-09-26
作為內太陽系的新訪客，C/ 2025 R 2 （SWAN）彗星有一條長長的離子尾巴，斜向延伸穿過 9 月 21 日記錄的這個近 7 度寬的望遠鏡視場。在SWAN 彗星綠色彗星的左上方可以看到一顆較暗的彗星--C/ 2025 K 1 （ATLAS），它也是首次在內太陽系亮相，在室女座的星海背景中清晰可見。這兩顆新彗星都是在 2025 年才被發現的，與它們一起出現在這個天體框架中的還有赤褐色的火星（下圖），它是地球夜空中更熟悉的流浪者。這兩顆彗星看似在賽跑，在穿越內太陽系和環繞太陽的航程中幾乎並駕齊驅。但是，這顆彗星 SWAN 已經在 9 月 12 日到達近日點或最接近太陽的位置，現在正沿著它的軌道向外移動。而這顆彗星ATLAS 仍在行進中，並將於 10 月 8 日到達近日點。
原文：A new visitor to the inner Solar System, comet C/2025 R2 (SWAN) sports a long ion tail extending diagonally across this almost 7 degree wide telescopic field of view recorded on September 21. A fainter fellow comet also making its inner Solar System debut, C/2025 K1 (ATLAS), can be spotted above and left of SWAN's greenish coma, just visible against the background sea of stars in the constellation Virgo. Both new comets were only discovered in 2025 and are joined in this celestial frame by ruddy planet Mars (bottom), a more familiar wanderer in planet Earth's night skies. The comets may appear to be in a race, nearly neck and neck in their voyage through the inner Solar System and around the Sun. But this comet SWAN has already reached its perihelion or closest approach to the Sun on September 12 and is now outbound along its orbit. This comet ATLAS is still inbound though, and will make its perihelion passage on October 8.
※ 本文由萌芽機器人自動轉貼自每日一天文圖（Astronomy Picture of the Day，APOD），原文為英文，正體中文是透過 DeepL 翻譯及 OpenCC 進行自動處理，內容僅供參考，若有任何錯誤之處還請見諒！
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