planetary nebula

基本解释

Such stars eventually blow off the material of their outer layers, which creates an expanding shell of gas called a planetary nebula.
这样的恒星最终炸开了它们的外层物质，形成了向外扩展的气体盔甲，名为行星状星云。
And it is these that are helping scientists to resolve the outstanding mysteries of the complex shapes and symmetries of planetary nebula.
在图片的“协助”之下，科学家们有望揭开揭开行星状星云复杂的结构，以及其对称性背后的谜团。
As for the spiral itself, current supposition is that this is the result of a star in a binary star system entering the planetary nebula phase, when its outer atmosphere is ejected.
至于螺旋本身，最近的推测是这是双子星系统中的一个恒星进入行星星云阶段的结果，此时它的外层大气会被喷出。

an expanding shell of gas surrounding a dying star, formed from matter ejected from the star's outer layers the gas is ionized by the remaining hot stellar core, emitting light in the process