Occasionally I say to a student, that’s “not rocket science”. This is probably annoying, and I should stop it. I am trying to say: “Don’t worry, it is easy, you can do it”, but I am not sure I am succeeding.
The expression implies that rocket science is hard. I am not sure this is true. Rocket trajectories in space are simply classical mechanics and are straightforward to calculate. It also begs the question: What if you are a rocket scientist and want to describe something as easy? You can’t say: “That’s not rocket science”, because it is rocket science.
I have been told that the answer is to say: “That doesn’t need a tiger team.” Tiger teams are what NASA’s rocket scientists calls teams of smart guys put together to solve problems.
Incidentally, I tried to look up the origin of the phrase “it’s not rocket science”, but the web let me down. Apparently people have no idea. Surprising, as presumably it is recent. I can’t imagine people using this expression in the 19th century.
That reminds me of this sketch:
http://www.youtube.com/watch?v=THNPmhBl-8I