Let's say (hypothetically) that you had a very, very fast spaceship. As in, it can accelerate to 0.5c in a minute. (Presumably, this would require some rather hardy Kerbals, but that's besides the point). It runs on Mysterium fuel, which never depletes (it's a mystery why!)
If this spaceship wants to transfer from Kerbin to Duna in the least amount of time possible*, what should the maneuver be? My intuition is that it could burn towards the target the whole time. But perhaps it is a prograde burn, and then a lot of radial burns? What is the fastest flightplan?
* Ignoring timed dilation. The point is not the 0.5c speed per se, but rather that the ship is very fast.