They were monitoring the upper air to collect evidence of atomic explosions.
他们正在检测高空空气以收集原子爆炸的证据。
原声例句
BBC 听力 2018年4月合集
Chinese scientists say they believed that North Korea's nuclear test site has been so badly damaged by atomic explosions that it's no longer usable.
中国科学家称其认为朝鲜核试验基地受原子弹爆炸影响已被严重损毁,再也无法运行。
奇趣工程百科
Upon viewing the first atomic explosion, Oppenheimer felt a cold satisfaction that soon turned to melancholy, as he grappled with the implications of his work.