可以怀疑飞碟的存在，也可以不相信有高度智慧的外星人，但我们得承认，宇宙时空的无限性注定什么都可能发生。本书以纪实手法记录了历史上较重大的UFO事件，其中不少是科学家和飞行员目击的。可见这是一个不忽视的谜。虽然我们对此还不能准确理解，但相信我们的后代一定会揭开事实的真相。
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