T Entropy fix (efix) 1.4d0 gamma 0. xBreach 42390 mHermes (kg) 1.013000000000000d5 1.225000000000000d0 0.000000000000000d0 0.000000000000000d0 Hermes atmosphere 0.010000000000000d5 0.045600000000000d0 0.000000000000000d0 0.000000000000000d0 Vacuum approximation p (Pa) rho (kg/m^3) u (m/s) v (m/s) Mass calculation: Hermes is a L=100m long x D=5m diameter cylinder with d=5mm thick walls made of Al, rhoAl=2700 kg/m^3 mHull = rhoAl*L*(pi*D)*d = 21195 kg mPayload = mHull mHermes ~= 42390 kg