我们对于未知的事物总是充满了好奇与遐想，奥妙无穷的茫茫宇宙更是任由我们思想的驰骋。我们对于宇宙的认识，已经由开始的神话传说走向了科学的探索，但是宇宙中依旧存在着许多我们无法解释的事物。除了地球之外，其它的星球是否也有生命物体的存在？关于UFO的频频的报道，是否真有外星人做客了地球？外星人与人类的文明的发展是否有着密切的关联？
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