rocket scientist

noun2

1. •
   (informal) An aerospace engineer who works with spacecraft.

   • Rocket scientists have calculated that a velocity of seven miles per second, or approximately 25,000 miles per hour, would be necessary for a rocket to escape the earth's gravity. — 1940
2. •
   (informal) One qualified to handle or understand things which are very complex or confusing; a very intelligent person.

   • You don’t have to be a rocket scientist to see that that idea won’t work.