Most likely it was what is known as a hole-punch cloud.

最有可能的是所谓冲孔云。

youdao

The cloud's round shape is likely what is known as a hole-punch cloud.

云的圆形很可能就是人们所称的穿洞云。

youdao

Heymsfield and colleagues flew smack-dab into the hole-punch discovery after having conducted a cloud study from a heavily instrumented turboprop plane near Denver International Airport in 2007.

海明斯菲尔德和同事们于2007年在丹佛国际机场附近的一个装备有许多仪器的涡轮螺旋桨飞机上展开云研究后不久就不偏不倚的发现了穿洞云。

youdao

Scrappers can also buy embellishments to suit any occasion, from a miniature Marine uniform to a hole-punch that makes tiny paper butterflies.

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Bob Tillman's biggest effort now is to punch a big hole in Depot's lucrative big-city monopoly.

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When this sort of star implodes, to create a black hole, it generates jets of material that punch their way out of the collapsing mass at near light-speed, to produce extremely high-energy emissions of light.

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