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Electromagnetic waves excited by satellites and space debris moving through the earth’s plasma in low earth orbit can be detected in situ by a technique called Space Object Identification by Measurements of Orbit-Driven Waves (SOIMOW). Proximity measurements of space objects with plasma waves may allow tracking of space debris below the normal detection thresholds traditionally accomplished by optical telescopes and radar ranging sensors. SOIMOW uses in situ plasma receivers to identify space objects during orbital conjunctions. Satellites and other space objects moving through the near-earth ionosphere between 200 and 1000 km altitude become electrically charged by both electron collection and photo emission in sunlight. These hypersonic, charged objects excite a wide range of plasma waves. The SOIMOW technique has shown that electromagnetic plasma waves from known objects may be observed out to ranges of tens of kilometers, providing information on presence of the space objects. The SOIMOW concept has been demonstrated with the Radio Receiver Instrument (RRI) on the Swarm-E satellite. The amplitude, spectral, and polarization changes of the RRI data are consistent with electromagnetic, compressional Alfvén waves that are launched by charged space objects traveling across magnetic field lines. In addition, electrostatic waves at the space object can be generated by a lower hybrid drift or an ion acoustic wave instability. Both in situ electric field probes and remote detection of scattered satellite waves are being investigated to determine the location of orbiting objects.
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Eulerian simulations of electrostatic waves in plasmas with a single sign of charge
An Eulerian, numerical simulation is used to model the launching of plasma waves in a non-neutral plasma that is confined in a Penning–Malmberg trap. The waves are launched by applying an oscillating potential to an electrically isolated sector at one end of the conducting cylinder that bounds the confinement region and are received by another electrically isolated sector at the other end of the cylinder. The launching of both Trivelpiece–Gould waves and electron acoustic waves is investigated. Adopting a stratagem, the simulation captures essential features of the finite length plasma, while retaining the numerical advantages of a simulation employing periodic spatial boundary conditions. As a benchmark test of the simulation, the results for launched Trivelpiece–Gould waves of small amplitude are successfully compared to a linearized analytic solution for these fluctuations.
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- Award ID(s):
- 2106332
- PAR ID:
- 10440336
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Physics of Plasmas
- Volume:
- 29
- Issue:
- 10
- ISSN:
- 1070-664X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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