Does creating more jobs actually help the economy as a whole?
Generally, whenever people have more income, it doesn't only benefit those people with more income. Imagine you somehow received \$100 that fell from the sky (or through NASA job). Would you save the entire \$100 and never spend it? More likely, you would spend some fraction of it... let's say you spend \$60. This money you spend will go to a shopkeeper, who then keeps a fraction and spend some of that \$60 on something else, and so on. So this extra money benefits other people too, not just the person receiving the money.

If you're interested, you can read more about this here.