Cool. But like others mentioned, even leaving aerobraking and parachutes out of the picture, a return trip to a planetary body is not simply the direct trip X 2. I mean, 20km/s for a round trip to the Mun, or Minmus seems way too much.
I love it! Great work! One question: on the previous page you said that a 1088 km x 1588 km transfer orbit has a 5/6 orbital period of a 1588 circular orbit and some formulas to calculate the transfer delta-v requirements. But how did you calculate that a 1088kmx1588km orbit is 5/6 of the orbital period of 1588kmx1588km? I ask because I would like to calculate an orbit with a 1/3 orbital period of a different circular orbit.