IV.   Spaceflight                

    This is the final part of "From Stargazers to Starships," a historical overview of spaceflight, stressing the technology of rockets, satellites and orbits, and its use in unmanned missions.

It consists of four main parts:

1.       The principles of rocketry and its evolution, from early Chinese rockets to Robert Goddard's work (especially the adaptation of the DeLaval nozzle), to rocket development in WW II and to the "space race" after the launch of Sputnik 1.

2.       The many different uses of unmanned spacecraft, with examples and links.

3.       Exotic means of flight into space--nuclear, light-gas cannon, solar sails and ion engines.

4.       Some orbits and orbital maneuvers of special significance--synchronous and sun-synchronous orbits, Lagrangian points and gravity-assist maneuvers, by which a spacecraft deflected my a moving planet can gain or lose velocity. That last item has an interesting connection to the water turbine designed by Lester Pelton in California, shortly after the Gold Rush.

   25. The Principle of the Rocket
   26. Robert Goddard and his Rockets
   27. The Evolution of the Rocket
   28. Spaceflight
   29. Spacecraft

    29a.  Satellites observing the Sun, solar system and the universe
    29b.   Satellites observing Earth from above
    29c.   Satellites which observe the local space environment
    29d.   Satellites for commercial benefits
    29e.   Missions to planets and distant space

   30. Far-out Pathways to Space: Great Guns?
    30a.    Project HARP and the Martlet
   31. Far-out Pathways to Space: Nuclear Power
   32. Far-out pathways to Space: Solar Sails
    32a.    Early Warning of Interplanetary Disturbances
   33. Ion Rockets

   34. Orbits in Space
    34a.    The Distance to the L1 Point
    34b.    The L4 and L5 Lagrangian Points
    34c.    The L4 and L5 Points--Another Derivation
   35. Starships
    35a.     Planetary Swing-by and the Pelton Turbine

   Afterword:   "Do Frogs Exist there Too ?"