What do thrusters push against in space?
Excuse me, but I have a question regarding the operation of thrusters in space. Could you please explain what exactly do these thrusters push against when they're operating in the vacuum of space? I understand that in an atmosphere, like Earth's, thrusters expel gas to create thrust, but how does this concept apply in the vast emptiness of space? It seems counterintuitive that something can push against nothing. I'm really curious about the physics behind this, so I'd appreciate your detailed explanation. Thank you.