Plasma Turbulence at Comet 67P/Churyumov‐Gerasimenko: Rosetta Observations. Issue 9 (28th August 2020)

• Record Type: Journal Article
• Authors: Ruhunusiri, S.; Howes, G. G.; Halekas, J. S.
• Is Part Of: Journal of geophysical research. Volume 125:Issue 9(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-08-28
• Subjects: Rosetta -- comet -- plasma turbulence -- 67P/Churyumov‐Gerasimenko -- magnetic field; Magnetospheric physics -- Periodicals; Space environment -- Periodicals; Cosmic physics -- Periodicals; Planets -- Atmospheres -- Periodicals; Heliosphere (Astrophysics) -- Periodicals; Geophysics -- Periodicals; 523.01
• DOI: 10.1029/2020JA028100
• Languages: English
• ISSNs: 2169-9380

Abstract

Abstract: We perform a power spectral analysis of magnetic field fluctuations measured by the Rosetta spacecraft's magnetometer at comet 67P/Churyumov‐Gerasimenko. We interpret the power spectral signatures in terms of plasma turbulent processes and discover that different turbulent processes are prominent during different active phases of the comet. During the weakly active phase of the comet, dominant injection is prominent at low frequencies near 10 −2 Hz, while partial energy cascade or dispersion is prominent at high frequencies near 10 −1 Hz. During the intermediately active phase, uniform injection is prominent at low frequencies, while partial energy cascade or dispersion is prominent at high frequencies. During the strongly active phase of the comet, we find that partial energy cascade or dissipation is dominant at low frequencies, while partial energy cascade, dissipation, or dispersion is dominant at high frequencies. We infer that the temporal variations of the turbulent processes occur due to the evolution of the plasma environment of the comet as it orbits the Sun. Key Points: Plasma turbulent processes at comet 67P vary temporally as it orbits the Sun For low frequencies, energy injection and partial energy cascade or dissipation are dominant For high frequencies, partial energy cascade, dissipation, or dispersion is dominant