From: ldo@nz.invalid   
      
   On Sat, 22 Jun 2024 08:37:00 -0000 (UTC), I wrote:   
      
   >     real(kind = useprec), parameter :: G = 0.001   
      
   OK, I figured out, this is lunar gravity in miles/second/second.   
      
   >     real(kind = useprec), parameter :: Z = 1.8   
      
   This is I think the rocket specific impulse.   
      
   >         delta_v = time_subinterval * fuel_rate / mass_total   
      
   This is not actually the change in velocity, it is the proportion of   
   spacecraft mass being expelled over the subinterval.   
      
   >                     Z &   
   >                 * &   
   >                     ( &   
   >                         delta_v &   
   >                     + &   
   >                         delta_v2 / 2 &   
   >                     + &   
   >                         delta_v2 * delta_v / 3 &   
   >                     + &   
   >                         delta_v4 / 4 &   
   >                     + &   
   >                         delta_v4 * delta_v / 5 &   
   >                     )   
      
   I think this contribution to the velocity comes from the rocket equation.   
   It’s a truncated power series; interestingly, it’s one with poor   
   convergence.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)