They do so with good reason. Consider the potential effects of a 50-megaton nuclear explosion, similar to the Tsar Bomba, detonated in October 1961, which shattered windows 900 kilometers (560 miles) away and sent a mushroom cloud rising above the stratosphere.
他们之所以如此，有很好的理由。想象一下， 50百万吨当量的核弹（类似于1961年10月引爆的沙皇炸弹（Tsar Bomba））能将900公里之外的窗户震碎，产生的蘑菇云可以达到平流层。