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A method for rapid earth reacquisition of a spacecraft. A three-axis inertial attitude of the spacecraft is determined by rotating the spacecraft about its pitch axis while measuring star patterns. A pitch axis of the spacecraft is aligned with earth's pole axis. The spacecraft is reoriented with re

A method for rapid earth reacquisition of a spacecraft. A three-axis inertial attitude of the spacecraft is determined by rotating the spacecraft about its pitch axis while measuring star patterns. A pitch axis of the spacecraft is aligned with earth's pole axis. The spacecraft is reoriented with respect to an earth-pointing reference frame.

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A method for rapid earth reacquisition of a spacecraft. A three-axis inertial attitude of the spacecraft is determined by rotating the spacecraft about its pitch axis while measuring star patterns. A pitch axis of the spacecraft is aligned with earth's pole axis. The spacecraft is reoriented with re

A method for rapid earth reacquisition of a spacecraft. A three-axis inertial attitude of the spacecraft is determined by rotating the spacecraft about its pitch axis while measuring star patterns. A pitch axis of the spacecraft is aligned with earth's pole axis. The spacecraft is reoriented with respect to an earth-pointing reference frame. cket attitude disturbance. 17. The system of claim 1 wherein the thrust vector controller controls slow dynamical motions and the at least one reaction control system controls rapid dynamical motions. 18. An attitude control system for controlling momentum vector force about a center of gravity of a rocket, the rocket having a central axis, the system comprising: a main propulsion nozzle having a main propulsion axis, the main propulsion nozzle disposed aft of the center of gravity; a main chamber providing a propelling gas to said main propulsion nozzle; a reaction control system, wherein the reaction control system is disposed forward of the center of gravity, wherein the reaction control system comprises a plurality of radial nozzles, wherein the plurality of radial nozzles are selectively and independently controlled; at least aerodynamic vane, the at least one aerodynamic vane having a leading edge, wherein the leading edge is positioned in the direction of travel; and a synchronizer for controlling an angle of attack of the at least one controllable aerodynamic vane and the plurality of radial nozzles. 19. An attitude control system as in claim 18, wherein the propelling gas is generated by gas generating means for generating said propelling gas selected from the group consisting of liquid propellant, solid propellant, steam and compressed gas. 20. An attitude control system as in claim 18, wherein the plurality of radial nozzles are symmetrically arranged around the periphery of the body in a common plane, wherein the common plane is at a right angle to the central axis. 21. The apparatus as set forth in claim 18, wherein the plurality of radial nozzles are arranged in non-common planes around the periphery of the body, wherein the non-common planes are at right angles to the central axis. 22. The apparatus as set forth in claim 18, wherein the plurality of radial nozzles are mounted flush with an outer surface of the body. 23. The apparatus as set forth in claim 18, wherein the plurality of radial nozzles comprises at least two straight radial nozzles. 24. The apparatus as set forth in claim 23, wherein the plurality of radial nozzles further comprises at least one tangentially canted radial nozzle, wherein the force generated by the at least one tangentially canted radial nozzle is orthogonal with respect to the central axis. 25. A rocket controller, the rocket controller disposed within a rocket, the rocket having forward and aft sections, a central axis, and a dynamic center of gravity, wherein the rocket controller comprises: at least one first thrust generator, wherein the at least one first thrust generator is located aft of the dynamic center of gravity; at least one first thrust vector controller, wherein the at least one first thrust vector controller controls the at least one first thrust generator; at least one second thrust generator, wherein the at least one second thrust generator is located forward of the dynamic center of gravity; and at least one second thrust vector controller, wherein the at least one second thrust vector controls the at least one second thrust generator. 26. A rocket controller as in claim 25 wherein the at least one second thrust vector controller is synchronized with the at least one first thrust vector controller. 27. A rocket controller as in claim 25, wherein the at least one first thrust generator comprises thrust propelling gas, wherein the thrust propelling gas is generated by gas generating means for generating said propelling gas selected from the group consisting of liquid propellant, solid propellant, steam and compressed gas. 28. A rocket controller as in claim 25, wherein the at least one second thrust generator comprises thrust propelling gas, wherein the thrust propelling gas is generated by gas generating means for generating said propelling gas selected from the group consisting of liquid propellant, solid propellant, steam and compressed gas. 29. A rocket controller as in claim 25, wherein the at least one second thrust generator comprises a plurality of radial nozzles, wherein the plurality of radial nozzles are symmetrically arranged around the rocket periphery in a common plane, wherein the common plane is at a right angle to the central axis. 30. A method for synchronizing forward and aft thrust vector control for a body traveling in a fluid, the body for minimizing fluid resistance and having forward and aft sections, primary thrust generator disposed in the aft section, and a secondary thrust generator disposed in the forward section, the method comprising the steps of: initiating the primary thrust generator; calculating a dynamic center of gravity for the traveling body; calculating a principal thrust axis generated by the primary thrust generator; determining an offset between the principal thrust axis and the dynamic center of gravity; and adjusting the offset to a predetermined value. 31. A method as in claim 30 wherein the step of adjusting the offset to the predetermined value further comprises the steps of: calculating a torque required to adjust the offset to the predetermined value; initiating the secondary thrust generator to apply the calculated torque; and steering the primary thrust generator to adjust the offset to the predetermined value. 32. A method as in claim 30 wherein the step of initiating the secondary thrust generator further comprises the step of adjusting a duty cycle of the secondary thrust generator. 33. A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for synchronizing forward and aft thrust vector control for a body traveling in a fluid, the body for minimizing fluid resistance and having forward and aft sections, a primary thrust generator disposed in the aft section, and a secondary thrust generator disposed in the forward section, said method steps comprising: initiating the primary thrust generator; calculating a dynamic center of gravity for the traveling body; calculating a principal thrust axis generated by the primary thrust generator; determining an offset between the principal thrust axis and the dynamic center of gravity; and adjusting the offset to a predetermined value, wherein the step of adjusting the offset further comprises the steps of: calculating a torque required to adjust the offset to the predetermined value; initiating the secondary thrust generator to apply the calculated torque; and steering the primary thrust generator to adjust the offset to the predetermined value. maintaining a specified degree of separation of satellites at a position of said satellites which has minimum separation. 6. A method as in claim 5, wherein said position of said minimum degree of separation is at apogee. 7. A method as in claim 5, wherein said minimum degree of separation is substantially two degrees of separation. 8. A method as in claim 1, wherein said communicating comprises avoiding communicating with said satellites during a position of said satellites that is within a specified interval near other satellites. 9. A method as in claim 8, wherein said other satellites are geosynchronous satellites. 10. A method as in claim 8, wherein said specified interval is substantially 40 degrees. 11. A method, comprising: causing a plurality of satellites to orbit the earth in elliptical orbits, forming repeating ground tracks, with a plurality of satellites in each ground track; defining an active arc within each ground track, which has a specified number of satellites within the active arc at any time; and communicating with said satellites only during the time when said satellites are within said active arc, wherein a specified degree of separation between satellites is substantially 40 degrees. 12. A method as in claim 11, wherein said defining comprises defining an active arc which has a specified degree of separation from a line of communication to geosynchronous satellites. 13. A method as in claim 11, wherein the specified number of satellites is greater than one. 14. A method as in claim 11, wherein there are satellites in ground tracks having apogees in the Northern Hemisphere, and separate satellites in ground tracks having apogees in the Southern Hemisphere. 15. A method as in claim 11, wherein said specified number of satellites within the active arc is at all times, the same integer number of satellites. 16. A method as in claim 15, said causing comprises causing each of the plurality of satellites to orbit in a specified orbit whereby as a first satellite leaves the active arc, another satellite enters the active arc. 17. A method as in claim 11, wherein said causing comprises establishing a predetermined minimum degree of separation between satellites. 18. A method as in claim 17, wherein said minimum degree of separation is substantially two degrees of separation. 19. A method as in claim 11, wherein said ground tracks are placed in a way that is effective is to avoid outages in coverage on the earth. 20. A method as in claim 11, wherein said satellite orbits at all points are below 22,300 miles of altitude. 21. A method as in claim 11, wherein said satellites orbit in an inclined elliptical orbit. 22. A method as in claim 21, wherein said inclined elliptical orbit is inclined substantially at 63.4 degrees. 23. A method, comprising: causing a plurality of satellites to orbit the earth in an inclined elliptical orbit with apogees below 22,300 miles and to pass into a first area where the satellites may interfere with communication wilt geosynchronous satellites, and a second area where the satellites could not interfere with communication with geosynchronous satellites, said plurality of satellites including a first plurality of satellites orbiting in a first common ground track that repeats an integer number of times per day, and a second plurality of satellites orbiting in a second common ground track, different from said first common ground track, and which also repeats an integer number of times per day; and communicating with said plurality of satellites only during a time when they are not in said first area, wherein said second area is defined as an area with a specified degree of separation from possible interference, wherein said specified degree of separation is substantially 40 degrees. 24. A method as in claim 23, wherein said communicating comprises communicating with said satellites during substantially 60 percent of their time within their orbit. s] Voss, L. "New Thrust for U.S. Satellites", Aerospace America, American Institute of Aeronautics & Astronautics, New York, vol. 38, No. 2, Feb. 2000, pp. 36-40. "Electric Propulsion", Aerospace America, American Institute of Aeronautics & Astronautics, New York, vol. 30, No. 12, Dec. 1, 1992, p. 42. Anzel, B., "Stationkeeping the Hughes HS 702 Satellite with a Xenon Ion Propulsion System," Congress of the International Astronautical Federation, Sep. 28, 1998.