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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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Plasma Turbulence at Comet 67P/Churyumov-Gerasimenko: Rosetta Observations.
S Ruhunusiri1, G G Howes1, J S Halekas1
1Department of Physics and Astronomy, The University of Iowa, Iowa City, IA, USA.
Journal of Geophysical Research. Space Physics
|August 12, 2021
Summary
Rosetta
Area of Science:
- Space Physics
- Plasma Physics
- Cometary Science
Background:
- Cometary plasma environments are complex and dynamic.
- Understanding turbulence at comets is key to unraveling plasma processes.
Purpose of the Study:
- To analyze magnetic field fluctuations at comet 67P/Churyumov-Gerasimenko.
- To identify and differentiate turbulent processes during various cometary activity phases.
Main Methods:
- Power spectral analysis of magnetic field data from Rosetta's magnetometer.
- Interpretation of spectral signatures in the context of plasma turbulence.
Main Results:
- Distinct turbulent processes dominate different cometary activity phases.
- Weakly active phase: dominant injection (low frequencies), partial cascade/dispersion (high frequencies).
- Intermediate phase: uniform injection (low frequencies), partial cascade/dispersion (high frequencies).
- Strongly active phase: partial cascade/dissipation (low frequencies), partial cascade/dissipation/dispersion (high frequencies).
Conclusions:
- Turbulent processes at comet 67P vary with its heliocentric distance and activity.
- Changes in turbulent processes are linked to the evolving cometary plasma environment.
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