open cluster

基本解释

Hence, it is rare that an open cluster survives long enough for one of its members to form a planetary nebula.
因此，一个疏散星团很少能够存活到它内部的某个成员变成行星状星云。
The stars will win in the end, destroying their pillars of creation over the next 100, 000 years, and resulting in a new open cluster of stars.
恒星将取得最终胜利，接下来的10万年恒星将摧毁它们的创造之柱，结果形成一个新的疏散星团。
When the watercolor-like cloud surrounding the open cluster of stars was first observed, it was thought to be leftover material from the formation of the cluster.
这种围绕在恒星疏散星团周围的水彩状气体云是第一次被观测到，一般认为这种气体云是恒星群形成后的剩余物质。

But at a nearby school, we are shown what Calacharo says is the norm, a small cluster of putrid open-pit latrines made of mud bricks worn to mere shells by rain and lack of repair.
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Opening the tailgate with its integrated rear light cluster reveals supplementary lights to warn approaching vehicles of the open tailgate.
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