I was 8 when i decided that robots will take over the work so parents can spend more time with their children. It's been an influence in my life ever since. I also read a magazine where someone was in a similar situation as yourself, and at around the same age (6-8yrs) they worried about earth being hit by a meteor and so decided as adult to change their career. In the new career they developed a way of using the wobble of a star to determine it is orbited by a planet, so humans can diversify to other worlds.