And fourth, it was found in exactly the way the hunt for Vulcan proceeded-by noting the slight dip in light from its parent star caused when it passed in front of that star.

第四，发现它的方法正和当年寻找火神星时依据的原理一样——即当行星在其围绕的恒星前穿过时，恒星的光线略有折射。这点被捕捉到了。

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And fourth, it was found in exactly the way the hunt for Vulcan proceeded-by noting the slight dip in light from its parent star caused when it passed in front of that star.

第四，发现它的方法正和当年寻找火神星时依据的原理一样——即当行星在其围绕的恒星前穿过时，恒星的光线略有折射。这点被捕捉到了。

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