This is a big change from earlier models where NASA led and controlled the development of space vehicles.

VOA: special.2010.04.28

That's why in the earlier models of the atom, they're not horrible to sometimes think about just each n value as a little ring around.

这就是为什么在早期原子模型中，人们没有感觉到把每一个，n，都想象成,一个绕核的小圆圈有什么不妥。

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