2025年7月25日
Twelve Years of Kappa Cygnids
Image Credit & Copyright: Petr Horálek, Josef Kujal, Tomáš Slovinský; Acknowledgement: Mahdi Zamani
Explanation: Meteors from the Kappa Cygnid meteor shower are captured in this time-lapse composite skyscape. The minor meteor shower, with a radiant not far from its eponymous star Kappa Cygni, peaks in mid-August, almost at the same time as the much better-known and better-observed Perseid meteor shower. But, seen to have a peak rate of only about 3 meteors per hour, Kappa Cygnids are vastly outnumbered by the more popular, prolific Perseid shower’s meteors that emanate from the heroic constellation Perseus. To capture dozens of Kappa Cygnids, this long term astro-imaging project compiled meteors in exposures selected from over 51 August nights during the years 2012 through 2024. Most of the exposures with identified Kappa Cygnid meteors were made in August 2021, a high point of the shower’s known 7-year activity cycle. All twelve years worth of Kappa Cygnids are registered against a base sea and night skyscape of the Milky Way above Elafonisi Beach, Crete, Greece, also recorded in August of 2021.
Tomorrow’s picture: light-weekend
十二年的天鹅座κ流星雨
影像提供与版权: Petr Horálek, Josef Kujal, Tomáš Slovinský; 致谢: Mahdi Zamani
说明: 这幅缩时的合成天空影像，呈现了来自天鹅座κ流星雨（Kappa Cygnid meteor shower）的流星。这群小流星雨的辐射点离据以得名的天鹅座κ星（Kappa Cygni）不远，而它在八月中旬的活动极大期，几乎与更知名且更热门的英仙座流星雨同期。不过，天鹅座κ流星雨的峰值流星出现率仅有每小时3颗，远远少于英仙座流星雨的流星出现率。也因此，为了累积数十颗天鹅座κ流星，这项长期的天文摄影计画，在2012年至2024年8月的51个夜晚进行观测取像，才得以合成出这幅流星影像。影像中，大多数经过确认的天鹅座κ流星记录于2021年8月，而这也是这群流星雨已知的7年活动周期的高峰。与这些十二年天鹅座κ流星叠合的希腊克里特岛埃拉福尼西海滩海景及上方的夜空银河，亦是摄于2021年的8月。
明日的图片: light-weekend
