The formation of this spiral structure may be caused by the anti-clockwise spin of umbra "A".

这种旋涡结构可能是由于A本影的逆时针自旋运动造成的。

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And some of them might be spinning clockwise, in which case, according to the right-hand rule we would consider them spin-down.

而另一些电子则是在顺时针自旋，在这种情况下，根据右手定理,我们会以为它是在向下转。

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Electrons are subatomic spinning tops: Spin up and spin down are the electron's version of clockwise and counterclockwise.

FORBES: Magazine Article