Plasma turbulence enhanced current collection: Results from the plasma motor generator electrodynamic tether flight

Abstract

The plasma motor generator (PMG) experiment, launched June 26, 1993, was a tethered system of two identical plasma contactors connected via a 500‐m conducting tether. The experiment was designed to demonstrate the ability of plasma contactors to provide a low‐impedance connection between a spacecraft and the ionosphere for both the electron emission and collection. The flight data indicate that plasma contactors enhance electron collection and emission by both neutralizing the electron space charge and scattering electrons across the geomagnetic field lines. Up to a 0.3 A steady current flowed along the tether in a circuit completed through the ionosphere. An analytical model for plasma contactor interaction with a background plasma which incorporates electron scattering by plasma waves is compared with the flight data. Good agreement between the model and the data is achieved for an effective scattering frequency equal to one twentieth of the local plasma contactor plasma frequency.

The PROPEL Electrodynamic Tether Demonstration Mission

“…The first was developed by Katz et al 12 and the second was proposed by Gerver et al 13 Because of differences between the two models, the Gerver et al model tends to predict higher collected electron current for a given emitted ion current level, HCPC bias voltage, and ionospheric condition.…”

Mission-function control of tethered satellite/climber system

“…In SEDS II, feedback breaking was employed in order to limit the swing angle of the deployed tether to 41. In the Plasma Motor Generator (PMG) mission, a 500 m tether was deployed to demonstrate electrodynamic tether operation [13]. The Tether Physics and Survivability Experiment (TiPS) was carried out in 1996 [14].…”

Jovian Orbit Capture and Eccentricity Reduction Using Electrodynamic Tether Propulsion

“…Electrodynamic tethers have been long considered for Jupiter and other planetary missions [3,4], and there have been several electrodynamic tether missions conducted in low Earth orbit [5,6]. More recently, electrodynamic tethers have been studied in greater depth for capture and tour in the Jovian system [7][8][9][10], though these studies have focused primarily on the capture phase without using flybys of the Jovian moons.…”