Space propulsion has changed little since mankind took its first tentative steps into space. Even with the incremental advances in the efficiency of chemical fuels; the basic nature of rocketry is still defined by the basic Delta V Rocket Equation with all its limitations; be it the powerful boosters used to obtain orbital velocity or the low impulse Ion Thrusters used to power deep space missions. This Neanderthal approach to propulsion limits both the potential flight parameters of deep space missions and the life span of earth orbiting satellites.
In earth orbiting satellites, the electronics of the satellite may last indefinitely; but the useable lifespan of that satellite is limited by the availability of on-board propellants used for orbital maintenance. Once the chemical propellant is exhausted, the satellite no longer has the capability of maintaining proper station.
The International Space Station is dependent upon chemical sport ticket propellants to offset orbital decay. The need and use of these chemical propellants increases the potential for catastrophic accident, increases the cost of operational maintenance, and requires the commitment of launch capacity for that purpose.
Interplanetary and deep space missions face similar limitations inherent to dependence on chemical propellants. Although gravitational assist has been a regular tool used in both navigation and imparting changes in specific orbital energy; obtainable velocities, launch sport ticket windows, and other flight parameters remain severely limited by dependence upon the same Newtonian Propulsion methods used by the ancient Chinese to power their rudimentary rockets. Even Ion Propulsion, which uses electro-magnetic acceleration of the ion fuel to achieve impulse, is still a type of Newtonian Propulsion where the total energy imparted is limited by exhaust velocity and total available fuel mass as defined by the basic rocket equation. Newtonian Propulsion may have gotten us to earth orbit and beyond; but it will be Electro-magnetic propulsion that will carry us to the stars. In the mean time, its development will allow us to achieve flight parameters unimaginable when considering only chemical propellants.
Prior to 1948 the ampere was defined, based on Faraday's Law Of Electrolysis, as the amount of unvarying current, that when passing through a solution of silver nitrate, deposits silver at a rate of .00111800 grams per second.
The ampere was redefined in 1948 as the amount of unvarying current, that when being carried by two infinitely long conductors separated by one meter, would generate a magnetic force between the conductors of 2 X 10-7 Newton per meter of length. This is the Standard International definition of an Ampere.
Electro-magnetic Propulsion sport ticket and it's inverse, Electro-dynamic Braking, when combined with the now and near term future technologies related to super conductivity, dielectric capacitance, and other related technologies; will introduce a new paradigm in space propulsion.
A simple space based experiment to demonstrate the basic principles of electro-magnetic propulsion sport ticket is easily imagined. In this experiment a simple coil, a number of accelerometers, a polarity reversing switch, power source, and radio telemetry is used to determine the earth's electro-magnetic field strength at the range of the experimental package. It would be most advantageous if the coil length is as great as possible. The coil is circuited in series with the polarity reversing sport ticket switch and the power source. The accelerometers serve to activate the polarity reversing switch. The experiment is then suitably packaged sport ticket and conventionally launched to a low inclination orbit. The experimental package is then positioned so that the field coil of the package is aligned so the coil will be at maximum repulsion with earth's electro-magnetic field when the coil circuit is initially energized.
Since the coil is aligned in repulsion with earth field, sport ticket one force will be acting along a line that is perpendicular to the earth's North/South polarity (approximating the line of orbital radius) and will translate to an acceleration vectored along the orbital radius converting circuit energy to increased gravitational potential.
The other force acting on the field coil will translate sport ticket to torque causing the field coil to begin to rotate about the central axis of the coil length as it begins to align towards the magnetic equilibrium position relative to earth field; that being one of maximum attraction and 180 degrees relative to the maximum repulsive position. In doing so, some of the electrical energy supplied to the field coil will be converted to kinetic rotational energy of the package. As the field coil rotates towards the equilibrium position, the accelerometer reading acceleration along the line of the orbital radius will sense zero acceleration as the angular relationship between the field coil and the earth's North/South polarity reaches 90 degrees relative to the maximum repulsion or attraction position. The coil polarity control circuit is designed to reverse the polarity of the field coil at this position, thus maintaining a repulsive relationship as the rotational inertia carries sport ticket the coil package through the 90 degree position.
As power is applied to the circuit, energy begins to be converted thru linear and rotational acceleration to the gravitational and rotational energy of the package. Without sport ticket empirical proof, I suggest that the applied coil circuit energy will be the sum of the energy translated to gravitational potential and rotational kinetic energy. That the linear force acting along the line of orbital radius will vary as the cosine of the relative field angle while the force translated to torque about the center axis of the coil will vary as a sine function of the relative field angle. The linear force will approximate the force at 0 degrees (maximum repulsion) times the cosine of the relative field angle. The force imparting torque about the center axis of the field coil will approximate the force imparting torque about the center axis of the field coil at 90 degrees (maximum torque) times the sine of the relative sport ticket field angle.
Using the Earth's magnetic field as a reaction field in attitude determination sport ticket and control of earth orbiting satellites was first proposed in the early 1960's. Current applications include the sensing of relative field angle to determine satellite attitude and the use of electro-magnets to maintain and change satellite attitude. The author believes that widespread application may be limited by the orbital perturbation that would result from earth field/satellite field interaction. Electro-magnetic attitude control, sport ticket without an Electro-magnetic orbital maintenance regime, would require expenditure of thruster fuel to maintain orbital station. To make electro-magnetic attitude determination and control a viable application, a means of offsetting the orbital perturbation using electro-magnetic propulsive technology rather than chemical thrusters must be developed. Also, the mass and volume fractions of electro-magnetic attitude determination and control technologies must be brought to values where the advantages of the technology offset the mass and volume fractions required. A primary advantage of Electro-magnetic propulsive methods for this application is that it can be accomplished without mechanical components as required in momentum and reaction wheel technology or the fuel and valving required for thrusters. This resulting increase in reliability will serve as further incentive to apply electro-magnetic technology to attitude control.
By definition, for an Earth orbital sport ticket escape mission, the Hyperbolic Excess Speed is the residual speed that remains as the space craft climbs sport ticket out of the Earth's gravity well. Simply stated, it approximates the rocket burn out velocity minus the escape velocity at the range of burnout.
It may be possible to increase the Hyperbolic Excess Speed by using magnetic repulsive force generated by propulsion coils aboard the spacecraft acting against Earth's electromagnetic field. The repulsive force would offset the deceleration of gravity as the space craft moves out of the Earth's gravity sport ticket well. This offsetting force would leave more residual or "Hyperbolic Excess Speed" as the space craft leaves the gravitational sphere of influence. If the magnetic repulsive force exceeds the gravitational force, then this force would continue to accelerate the space craft, imparting additional mechanical energy. The additional specific mechanical energy conserved or imparted would approximate the applied circuit energy calculated sport ticket as applied power times time.
A number of deep space missions have used Gravity Assist sport ticket to either increase or decrease the mechanical energy of the space craft. Although such maneuvers use the gravitational acceleration of the assisting planet to increase or decrease the specific mechanical energy of the space craft, the Hyperbolic Excess Speed of the space craft relative to the assisting planet remains unchanged. The reason for this is the relative velocity between the space craft and the assisting planet gained by the acceleration of gravity on the approach trajectory is lost to that same gravitational force on the departure trajectory.
By using Electro-magnetic propulsion, additional hyperbolic excess speed can be imparted when the assisting planet has a significant magnetic field. In this application the propulsion coil(s) are used in attraction polarity on the approach to the assisting planet. This increases the acceleration above that imparted by gravity sport ticket alone. As the space craft begins its departure trajectory from the assisting planet the relative sport ticket polarity is reversed and maintained in repulsion; offsetting the deceleration imparted by gravity, thus conserving the Hyperbolic Excess Speed of the spacecraft relative to the assisting planet by adding sport ticket the energy imparted by the electro-magnetic system to the
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