Ha ha, that's hilarious.  If space is a vacuum, what would those rockets push against?? 

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I would say "this isn't rocket science" but for the low-level of flat-earthism, perhaps rocket science is actually necessary! HAHAHA
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A rocket engine doesn't need to "push off" against anything to work.  
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You can see this is the case with a toy balloon -- just blow it up and let it go, and it accelerates AWAY from where the air comes out.
In the case of the balloon, the wobbling air nozzle changes direction so the balloon goes to and fro not in a straight line.
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A rocket engine can operate just fine in a vacuum where there is no ambient air.
It doesn't need any air to "push off from" because there is a force inherent in the velocity and mass of the escaping gasses.
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You have to figure in the weight (mass actually) of the gasses escaping AND their speed (or velocity) because force is a product of these two very different things.
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That's why when flat-earthers try to explain something by saying the weight exceeds the velocity you can tell they don't know what they're talking about. 
Because weight cannot exceed velocity. Velocity cannot exceed weight.
Weight and velocity are like apples and oranges. You can't compare them to each other.
Unless, that is, you enjoy mixing apples and oranges. 
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I know, when I post more than one sentence it's too hard to understand it all.
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Sound bytes for small minds.
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A rocket engine doesn't need to "push off" against anything to work.  

There are these guys who do youtube videos with what they claim is a vacuum chamber and they show that a fan won't even move a feather in a vacuum and rockets don't work either, unless they are provided, iirc, some oxygen in a temporarily enclosed environment to ignite in and then they can provide thrust in a vacuum.  So, they need a micro environment that is not a vacuum, in order to provide propulsion through a vacuum.  

The propulsion system of the Apollo Command Module was supposed to have used Hypergolic propellant, consisting of a fuel and an oxidizer, that unlike gasoline and oxygen for example, will spontaneously ignite when combined, forming a very reliable ignition system.  

The NASA space shuttle never had a mission to take it around the moon.

I suppose the thurst would be something like the recoil on a gun, sort of pushing against itself, if this very cool and interesting system had ever actually been to Space!    

Sorry Neil  :baby:

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You suppose "thrust" is the same as "thurst?" Hmmmm...
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A gun fired in a vacuum has the same recoil that it does in ambient atmosphere.
But to fire in a vacuum you need to have oxygen in the shell for combustion.
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Rocket engines don't need atmosphere to work. Any low-level technician knows that.