烏拉圭上空的 G 3 ATLAS 彗星
Comet G3 ATLAS over Uruguay
來源：Mauricio Salazar｜發表日期：2025-01-28
彗星可以是巨大的。當遠離太陽時，彗星的大小通常是指它由冰和岩石組成的堅硬的核，通常只有幾公里長，甚至比一顆小衛星還小。然而，當接近太陽時，彗核會噴射出塵埃和氣體，並留下一條細細的尾巴，尾巴的長度可以非常大，甚至超過地球和太陽之間的距離。如圖所示，C/ 2024 G 3 (ATLAS)彗星的尾部由反射太陽光的塵埃和發光氣體組成，其長度是滿月的數倍，在長焦相機拍攝的影像上甚至比肉眼看到的還要大。這張特寫圖片顯示的是大約一週前，ATLAS 彗星在烏拉圭聖何塞馬霍馬山的樹木和草地上空給人留下的深刻印象。 G 3 ATLAS 彗星在地球南半球的日落時分顯得格外耀眼，但隨著它逐漸遠離太陽，它的彗尾也變得越來越難看。 相簿：阿特拉斯彗星（G 3 ）
原文：Comets can be huge. When far from the Sun, a comet's size usually refers to its hard nucleus of ice and rock, which typically spans a few kilometers -- smaller than even a small moon. When nearing the Sun, however, this nucleus can eject dust and gas and leave a thin tail that can spread to an enormous length -- even greater than the distance between the Earth and the Sun. Pictured, C/2024 G3 (ATLAS) sports a tail of sunlight-reflecting dust and glowing gas that spans several times the apparent size of a full moon, appearing even larger on long duration camera images than to the unaided eye. The featured image shows impressive Comet ATLAS over trees and a grass field in Sierras de Mahoma, San Jose, Uruguay about a week ago. After being prominent in the sunset skies of Earth's southern hemisphere, Comet G3 ATLAS is now fading as it moves away from the Sun, making its impressive tails increasingly hard to see. Gallery: Comet ATLAS (G3)
※ 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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