I read a book when I was a teen and I’ll try my best to give as much detail and hopefully someone can help me find it. The story was about a set of astronauts who while in space had a child.
From what I remember, the child returns to earth, older now, maybe 20s/30s without the parents. The adult was human, but had qualities about him that seemed unhuman. A group of scientists were studying him, among them a women he bonds with. The man has the ability to transcend or astral travel from his own body, like an outer body experience. I think he had other abilities with electricity as well that I’m not sure about.
I can recall him going to the bottom of a pool and transcending from his body there. My memory isn’t very good but he is able to teach a women on earth to do this outer body experience as well. I might be remembering wrong but I think the man from space ends up dying. But before that he does form a loving bond with the women he taught.
