OP that none of you complied with...
A vacuum is Nothing; the very definition of the word in fact.
First question: how can you push on nothing?
Please supply the FULL definition of Newton's 3rd Law before answering, please!
Again, with this nonsense?
Newton's 3rd law. For every action, there is an equal and opposite reaction. Or, when one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body. You choose which one you want, they both mean the same thing.
How can you push on nothing? You can't. It's impossible. You can, however, push on a gas. And the gas can push on you. That's how rockets work. Simples. Explained in excruciatingly simple terms for the hard of thunking.
Carry on mooing, Poppa, it's when you make most sense.