The "Reset" button brings the simulation to its initial position. You can start or stop and continue the simulation with the other button. If you choose the option "Slow", the movement will be 4 times slower. You can vary (within certain limits) the values of eccentricity, orbital speed and semimajor axis.
*Bonus: it calculates accurately the launch angle when river velocity is greater than boat/swimmer velocity.
Click button when it is activated!
Use different hide/show togglers to visualize individual parameters and have fun learning.