Wrong, TexasH; this is why I told you we are not 'conversing'; the expanding exhaust of the rocket is clearly the propellant, P; so where is the object B necessary for motion to be produced?
No-one has addressed this logically, so here it is again:
Let's look at two of the preferred analogies for rocket propulsion, then at a rocket itself, & compare them.
1: A cannon firing a cannon-ball. Here you have object A, the cannon, object B, the cannon-ball, with the propellant, P (i.e. the expanding gunpowder) between them.
THREE objects.
2: The man on skateboard throwing a ball. Again you have object A, man on skateboard, object B, the ball, with the propellant, P (i.e. the expansion of the man's arm) between them.
Again; THREE objects.
Now let's look at a rocket: here, you have only object A, the rocket, & the propellant, P (i.e. the expanding fuel).
Only TWO objects.
Object B is missing in the rocket example.
And object B is the necessary recoil mass required to produce motion.
But we know a rocket DOES produce motion in an atmosphere, don't we?
So, some other mass MUST be taking the place of object B.
& the ONLY possibility for that other mass is the mass of the Atmosphere.
Thus, we get object A, the rocket, object B, the atmosphere, with the propellant, P (i.e. the expanding fuel) sitting between them.
THREE objects.
The requirements for Newton 2 & 3 are fulfilled & motion can be produced.
So, NO atmosphere equals NO motion; therefore rockets CANNOT function in a vacuum.
Q.E.D.