3 I/ATLAS
3I/ATLAS
發表日期：2025-07-17
3 I/ATLAS 於 7 月 1 日在智利里奧烏爾塔多由美國國家航空航天局（NASA）資助的ATLAS（小行星撞擊地球最後警報系統）巡天望遠鏡中被發現，它是繼 2017 年的 1 I/ʻOumuamua 和 2019 年的 2 I/Borisov 彗星之後，第三個穿過太陽系的已知星際天體。 3 I/ATLAS 也被稱為 C/ 2025 N 1 ，它顯然是一顆彗星，從夏威夷毛納凱亞雙子座北大型望遠鏡拍攝的這些影像中，我們可以很容易地看到它的瀰漫彗星纓，即圍繞著冰核的氣體和塵埃雲。左圖是彗星在天空中移動時與固定背景恆星連續曝光的軌跡。使用了三種不同的濾光片，分別顯示為紅色、綠色和藍色。在右圖中，多次曝光被記錄併合併成一張彗星影像。這顆彗星的星際起源也可以從它的軌道上看出來，它的軌道被確定為偏心的高雙曲線軌道，不會繞太陽執行， 3 I/ATLAS 將返回星際空間。 3 I/ATLAS 不會對地球構成威脅，這顆進入的星際干擾者目前處於木星與太陽的軌道距離之內，而它與太陽的最近距離將使它處於火星的軌道距離之內。
原文：Discovered on July 1 with the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert, System) survey telescope in Rio Hurtado, Chile, 3I/ATLAS is so designated as the third known interstellar object to pass through our Solar System It follows 1I/ʻOumuamua in 2017 and the comet 2I/Borisov in 2019. Also known as C/2025 N1, 3I/ATLAS is clearly a comet, its diffuse cometary coma, a cloud of gas and dust surrounding an icy nucleus, is easily seen in these images from the large Gemini North telescope on Maunakea, Hawai‘i. The left panel tracks the comet as it moves across the sky against fixed background stars in successive exposures. Three different filters were used, shown in red, green, and blue. In the right panel the multiple exposures are registered and combined to form a single image of the comet. The comet's interstellar origin is also clear from its orbit, determined to be an eccentric, highly hyperbolic orbit that does not loop back around the Sun and will return 3I/ATLAS to interstellar space. Not a threat to planet Earth, the inbound interstellar interloper is now within the Jupiter's orbital distance of the Sun, while its closest approach to the Sun will bring it just within the orbital distance of Mars.
※ 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！
關於每日一天文圖：每日一天文圖網站是美國國家航空暨太空總署與密西根理工大學提供的服務，網站每天提供一張影像或圖片，並由天文學家撰寫扼要說明其特別之處。