Notes from Independent Study Meeting
                      Feb 10, 2022

Present: Richmond, Dayal

  - Dayal shows the results of adding a photon force to the
          simulation, for three sails

          - realistic sail falls into Sun, but more slowly than
                 a photon-force-less sail

          - "thin foil" takes much longer to fall into Sun

          - unrealistically low density sail accelerates away from 
                 Sun, reaching 10 AU in about 2 years

  - goals for next meeting (Mon, Feb 14): 
   
          - compare trip of unrealistic sail to Saturn to the trip of 
                 real NASA probes to Saturn.  How does the duration 
                 of journey compare?  How to masses of vehicles compare?

          - adopt "thin foil" sail, area 1m x 1m, mass 0.005 kg, for the
                 following simulations

                 - start at x = 1.5 x 10^(11) m, y = 0, z = 0
                 - start with  vx = 0, xy = 29400 m/s, vz = 0

                 - run for 2 years WITHOUT any photon force
                 - run for 2 years WITH        photon force
                        compare final positions, velocities

                 - run for 200 years WITHOUT any photon force
                 - run for 200 years WITH        photon force
                        compare final positions, velocities