ABOUT ELECTRODYNAMIC TETHER, ITS STABILIZATION, ITS ADVANTAGES. In an “electrodynamic tether drag” system, such as the Terminator Tether, the tether can be used to reduce the orbit of the spacecraft to which it is attached. The motion of the long conducting wire of a tethered satellite across the geomagnetic field creates an emf of about – V/m along the length of the tether.

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It used super-strong strands of Kevlar as a strength-providing member, wound around the copper and insulation. As a result, there are a number of theories for the varying collection techniques.

The physical design of each of these structures as well as the current emission capabilities are thoroughly discussed. Well, just such a shift in mood could be upon us.

Science fiction author David Brin has made a good story from available; you might want to go read Tank Farm Dynamo. The electron and ion density varies according to various electrodunamic, such as the location, altitude, season, sunspot cycle, and contamination levels.

Electrodynamic Tethers: Getting into the Swing

It is similar to the winding in an electric motor pushing against the magnets of its armature, causing a torque force. I will amend this post if I think of a better tetjer. This model is compiled from a collaborative effort between magnetic field modelers and the institutes involved in collecting and disseminating magnetic field data from satellites and from observatories and surveys around the world.

If anyone knows where a copy might be available please contact us at webmaster This one is from the hand held Infrared Camera and is not as clear as the other one was and it does not have the interview and actual tether deployment portion that the above text was quoted from.

All of the theory presented is used towards developing a current collection model to account for all conditions encountered during an EDT mission. Functionally, electrons flow from the space plasma into the conductive tether, are passed through a resistive load in a control unit and are emitted into the space plasma by an electron emitter as free electrons.

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TUI: Engineering the Future

Of course, these measures would have severely restricted the power or propulsion that could be obtained by tether operation and could not be tolerated on an experiment that was not just a proof-of-concept.

Once the electrons are thermionically emitted from the TC surface they require an acceleration potential to cross a gap, or in this case, the plasma sheath. Furthermore, the propulsion version can be used to keep low-orbiting satellites, which are exposed to minute but continuous aerodynamic drag, at a proper altitude and thus prevent them from falling from the sky. The advantage to this revolutionary advance in propulsion is that it does not require any rocket fuel If successful electrodynamic tethers could prove a way to greatly decrease the cost of in space propulsion.

This current will, in turn, interact with the Earth’s magnetic field to cause a Lorentz JXB force which will oppose the motion of the tether and whatever it is attached to. To calculate the in-plane and out-of-plane directions, the components of the velocity and magnetic field vectors must be obtained and the force values calculated. When the tether intersects the planet’s magnetic fieldit generates a current, and thereby converts some of the orbiting body’s kinetic energy to electrical energy.

OML theory [13] is defined with the assumption that the electron Debye length is equal to or larger than the size of the object and the plasma is not flowing. In a similar vein to the STS 48 and 80 footage, this latest material to be gleaned from the unwitting NASA organisation goes much further, showing objects moving around an enormous tether and structured craft in flight. On Flight Day 3, the crew will begin deployment by raising a 40 foot 12 meter deployment boom that elevates the satellite and its support structure to this height.

The B direction changes as the tether orbits the Earth, and thus the direction and magnitude of the ED forces also change. The gravity gradient field also known as the “tidal force” will tend to orient the tether in a vertical position.

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Electrodynamic Tethers: Getting into the Swing

A satellite at its upper electrodynamiv collected electrons, and an electron gun at the lower end emitted electrons to complete the circuit. Without the magnetic field present, the current in the wire wouldn’t generate any force. This assessment follows analysis by a joint U. The first layer is a positive layer at the edge of the high potential plasma the contactor plasma cloud.

Electrodynamic tether

This was demonstrated during the Shuttle orbiter’s TSS-1R mission, when the shuttle itself was used as a large plasma contactor to provide over an ampere of current. If the tether geometry is a flat tape, then an approximation can be used to convert the normalized tape width to an equivalent cylinder radius. This voltage, which is called the “motional EMF”, can be up to several hundred volts per kilometer. As a result of this process, an electrodynamic force acts on the tether and attached object, slowing their elecfrodynamic motion.

This Science Fiction in the News story used with permission from Technovelgy.

In the case of the TSS-1R tether, its 20 km length produced a maximum of about V electrodynamiv between its most positive and negative ends, since it wasn? In terms of electrorynamic, the kinetic “movement” energy of the satellite and tether system orbiting around Earth is converted into electric energy. However, the technology is touted as a promising candidate to deorbit space debris at low cost. Ekectrodynamic Zhang, et alStone and Raitt andand Stone, et al Stanford Research Institute data sheet.

By adding a battery or solar panel to the EDT circuit, the induced current is overcome, reversing the current direction; the force experienced by the tether is now in the same direction as the EDT’s motion. This story is a poignant tale of what might have been in the last century of American space travel.