Jack Williamson 
Moon Children 

An international agency, COSMOS, is in charge of space exploration in the not very distant future. Odd forms of life have been discovered on Mars, Venus, and Jupiter; there may be a life form on Mercury; and finally something utterly mystifying is discovered on the moon. Three astronauts land and examine an installation that all three perceive as radically different – one sees a heap of gold, one a fort bristling with guns, one a space platform and space craft. They return to Earth with some crystals picked up at the mystery site.All three soon produce children – the moon children, gifted, precocious, and seemingly damned by the crystals their fathers had handled. Two are eerily beautiful, the third a grotesque monster. And the three soon discover that they are Earth’s hope for survival, as interplanetary invasion brings overwhelming alien forces to bear on mankind.