As it was science fiction and not many books were written by that time, he thought that the audience will be bored at something that was so unlikely to happen, lately they all panicked at the story and many bought it as true.
A story written in 1st person pov is more believable because the person is talking about their experiences and opinions. First person point of view also helps the story become more interesting because you know how the person feels, and their thoughts on certain things.
