M51: 潮汐流与氢α峭壁

2024年12月13日

M51: Tidal Streams and H-alpha Cliffs
Image Credit & Copyright: The Deep Sky Collective – Tim Schaeffer,
Carl Björk, Steeve Body, Fabian Neyer, Aki Jain, Ryan Wierckx, Paul Kent, Brian Valente, Antoine & Dalia Grelin,
Nicolas Puig, Stephen Guberski, Mike Hamende, Julian Shapiro, John Dziuba, Mikhail Vasilev, Bogdan Borz, Adrien Keijzer

Explanation: An intriguing pair of interacting galaxies, M51 is the 51st entry in Charles Messier’s famous catalog. Perhaps the original spiral nebula, the large galaxy with whirlpool-like spiral structure seen nearly face-on is also cataloged as NGC 5194. Its spiral arms and dust lanes sweep in front of its smaller companion galaxy, NGC 5195. Some 31 million light-years distant, within the boundaries of the well-trained constellation Canes Venatici, M51 looks faint and fuzzy to the eye in direct telescopic views. But this remarkably deep image shows off stunning details of the galaxy pair’s striking colors and fainter tidal streams. The image includes extensive narrowband data to highlight a vast reddish cloud of ionized hydrogen gas recently discovered in the M51 system and known to some as the H-alpha cliffs. Foreground dust clouds in the Milky Way and distant background galaxies are captured in the wide-field view. A continuing collaboration of astro-imagers using telescopes on planet Earth assembled over 3 weeks of exposure time to create this evolving portrait of M51.

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Tomorrow’s picture: moonship

M51: 潮汐流与氢α峭壁
影像提供与版权: The Deep Sky Collective – Tim Schaeffer,
Carl Björk, Steeve Body, Fabian Neyer, Aki Jain, Ryan Wierckx, Paul Kent, Brian Valente, Antoine & Dalia Grelin,
Nicolas Puig, Stephen Guberski, Mike Hamende, Julian Shapiro, John Dziuba, Mikhail Vasilev, Bogdan Borz, Adrien Keijzer

说明: 很有趣的互扰星系对M51，是梅西耶著名星表所收录的第51号天体。其中的正向大星系或许也是“螺旋星云”的原型，它具有涡旋状的外观，也另拥有NGC 5194的编录号。而它的螺旋臂和尘埃带拂过伴星系NGC 5195（右）的前方。M51距离我们约3,100万光年远，位在北天猎犬座的边界之内，用望远镜直接观看时，其身影昏暗且模糊。不过，这幅精采的极深空影像，却能细致的呈现这对星系吸睛的色彩及潮汐流。这幅影像更整合了大量窄波段数据，以突显不久前刚发现于M51系统、名为氢α峭壁的广袤泛红电离氢气云。此外，这幅宽视野影像，也记录了前景的银河系尘埃云和遥远的背景星系。地球各地的望远镜天文影像工作者携手合作，累积超过3星期的长曝光影像数据，才为不停演化的M51拍下了这张肖像。

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明日的图片: moonship