I hope you can answer my questions. When this mission actually happens in the 2030's, what will actually take Orion to Mars? Will there be a rocket more powerful than the SLS that can complete the six month journey? Or will the SLS or it's successor separate along the way - paving the way for some other propulsion system or rocket that is capable of taking Orion to Mars?
If so, would it be something smaller? How much of the journey requires rocket propulsion? How much coasting is there?