恩克彗星与蝌蚪云

2023年10月27日

Encke and the Tadpoles
Image Credit & Copyright: Dan Bartlett

Explanation: History’s second known periodic comet is Comet Encke (2P/Encke). As it swings through the inner Solar System, Encke’s orbit takes it from an aphelion, its greatest distance from the Sun, inside the orbit of Jupiter to a perihelion just inside the orbit of Mercury. Returning to its perihelion every 3.3 years, Encke has the shortest period of the Solar System’s major comets. Comet Encke is also associated with (at least) two annual meteor showers on planet Earth, the North and South Taurids. Both showers are active in late October and early November. Their two separate radiants lie near bright star Aldebaran in the head-strong constellation Taurus. A faint comet, Encke was captured in this telescopic field of view imaged on the morning of August 24. Then, Encke’s pretty greenish coma was close on the sky to the young, embedded star cluster and light-years long, tadpole-shaped star-forming clouds in emission nebula IC 410. Now near bright star Spica in Virgo Comet Encke passed its 2023 perihelion only five days ago, on October 22.

Tomorrow’s picture: mostly a ghostly weekend

恩克彗星与蝌蚪云
影像提供与版权: Dan Bartlett

说明: 人类所知的第二颗周期彗星是恩克彗星（2P/Encke）。当它在太阳系里穿行时，恩克彗星的轨道把它从远在木星轨道附近的远日点，带到紧贴在水星轨道之内的近日点。回归周期为3.3年的恩克彗星，是太阳系主要彗星的周期中最短者。恩克彗星至少还与地球的二群、活跃期在每年的10月底和11月初的流星雨有关联，它们分别是金牛北支和金牛南支流星雨。而它们个别的辐射点都在金牛座的亮星毕宿五附近。在这片记录于8月24日清晨的望远镜视野里，恩克彗星仅是一颗昏暗的彗星。在拍照的当时，恩克美丽的泛绿彗发于天空中的位置，紧邻着发射星云IC 410里的年轻内嵌星团及长约数光年的蝌蚪状恒星形成云。目前在室女座亮星角宿一附近的恩克彗星，在5天前的2023年10月22日通过近日点。

明日的图片: mostly a ghostly weekend