And since they're placed irregularly on an oblong shape, one researcher compared tracking the comet to trying to hit a knuckleball.

而且因为它们是被不规则地放置在一个长方椭圆形状上的，一个研究员尝试了追踪彗星或是试图击中一个节点两种方法。

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Arrow: Printing fault in gravure which appears as a mark in the shape of an arrow head on the print. Also called comet.

箭形印记：是照相凹版印刷的瑕疵。印刷品上带有像箭头的印纹。亦称慧星印记。

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Arrow: Printing fault in gravure which appears as a mark in the shape of an arrow head on the print. Also called comet.

箭形印记：是照相凹版印刷的瑕疵。印刷品上带有像箭头的印纹。亦称慧星印记。

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