Near the space center in Houston,Texas, some amateur star-watchers were trying to see the Apollo spacecraft through telescopes.

VOA: special.2009.07.22

So this is the 1 s star, sigma 1 s star orbital, and what you have in the center here is a node, right in the center between the two nuclei.

这是1s星，sigma1s星轨道，中间这个是节点，它在两个原子核中间。

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