风中凌乱的NGC 3199
当一阵恒星风吹乱了星云……
这个回答很好,还科普了有关激波的知识:为什么音障出现在音速附近，是巧合吗？
优秀的内容创作者都注销了啊……伤心……
原文
Explanation: NGC 3199 lies about 12,000 light-years away, a glowing cosmic cloud in the nautical southern constellation of Carina. The nebula is about 75 light-years across in this narrowband, false-color view. Though the deep image reveals a more or less complete bubble shape, it does look very lopsided with a much brighter edge along the top. Near the center is a Wolf-Rayet star, a massive, hot, short-lived star that generates an intense stellar wind. In fact, Wolf-Rayet stars are known to create nebulae with interesting shapes as their powerful winds sweep up surrounding interstellar material. In this case, the bright edge was thought to indicate a bow shock produced as the star plowed through a uniform medium, like a boat through water. But measurements have shown the star is not really moving directly toward the bright edge. So a more likely explanation is that the material surrounding the star is not uniform, but clumped and denser near the bright edge of windblown NGC 3199.
生词
nautical 航海的,海上的 (和naughty一点也不一样)
lopsided 不均衡的,向一侧倾斜的
bow shock 弓形激波
plow - plough 耕作
clumped 成块的,成从的
翻译
说明: NGC 3199是位在船底座方向，离我们约12,000光年远的明亮宇宙云。在这张窄波段假色影像里，这团星云涵盖约75光年的区域。虽然深空影像指出它具有接近完整的气泡结构，不过它的上缘远亮于其他区域。星云的中心附近，有颗会发出强烈恒星风的炽热短命沃夫-瑞叶型恒星。当沃夫-瑞叶型恒星的强烈恒星风扫集周围的星际物质时，往往会造就外观饶有趣味的星云。在上面这个案例里，原先以为明亮的前沿是恒星高速穿过均匀介质，所形成的弓形震波，酷似船只于水面产生的船首波。然而，量测指出这颗恒星并非往亮沿移动。因此，更合理的解释是这颗恒星周围物质的分布不均匀，靠气泡星云NGC 3199亮沿这侧的物质较密集。
