NGC 2419：星系间流浪者
(原标题: NGC 2419: Intergalactic Wanderer)
2023-04-13
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球状星团NGC 2419的恒星被挤进哈勃太空望远镜的视野，朝向隐秘的山猫星座。画面边缘附近的两颗明亮的尖状恒星位于我们自己的星系内。NGC 2419本身很遥远，距离我们大约30万光年。相比之下，银河系的卫星星系大麦哲伦星云距离我们只有16万光年。NGC 2419与其他大型球状星团（如半人马座Omega）大致相似，本质上是明亮的，但由于距离太远而显得暗淡。它的极端距离使得研究和比较它与银河系光晕中漫游的其他球状星团的性质变得困难。NGC 2419有时被称为“星系间流浪者”，它似乎确实来自银河系之外。对星团在太空中运动的测量表明，它曾经属于人马座矮球状星系，这是另一个小卫星星系，由于与大得多的银河系的反复相遇而被破坏。
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Stars of the globular cluster NGC 2419 are packed into this Hubble Space Telescope field of view toward the mostly stealthy constellation Lynx. The two brighter spiky stars near the edge of the frame are within our own galaxy. NGC 2419 itself is remote though, some 300,000 light-years away. In comparison, the Milky Way's satellite galaxy, the Large Magellanic Cloud, is only about 160,000 light-years distant. Roughly similar to other large globular star clusters like Omega Centauri, NGC 2419 is intrinsically bright, but appears faint because it is so far away. Its extreme distance makes it difficult to study and compare its properties with other globular clusters that roam the halo of our Milky Way galaxy. Sometimes called "the Intergalactic Wanderer", NGC 2419 really does seem to have come from beyond the Milky Way. Measurements of the cluster's motion through space suggest it once belonged to the Sagittarius dwarf spheroidal galaxy, another small satellite galaxy being disrupted by repeated encounters with the much larger Milky Way.