Search Publications
Solar cycle variations of the Cluster spacecraft potential and its use for electron density estimations
Fazakerley, A. N.; Trotignon, J. -G.; Haaland, S. +5 more
A sunlit conductive spacecraft, immersed in tenuous plasma, will attain a positive potential relative to the ambient plasma. This potential is primarily governed by solar irradiation, which causes escape of photoelectrons from the surface of the spacecraft, and the electrons in the ambient plasma providing the return current. In this paper we comb…
Nonlinear spatiotemporal evolution of whistler mode chorus waves in Earth's inner magnetosphere
Omura, Yoshiharu; Summers, Danny; Lee, Dong-Hun +1 more
We analyze the nonlinear evolution of whistler mode chorus waves propagating along a magnetic field line from their equatorial source. We solve wave evolution equations off the equator for the wave magnetic field amplitude and wave frequency, subject to boundary conditions at the equator comprising model “chorus equations” that describe the genera…
Wave-particle interaction in a plasmaspheric plume observed by a Cluster satellite
Yuan, Zhigang; Zhou, Meng; Deng, Xiaohua +5 more
The wave-particle interaction is a possible candidate for the energy coupling between the ring current and plasmaspheric plumes. In this paper, we present wave and particle observations made by the Cluster C1 satellite in a plasmaspheric plume in the recovery phase of the geomagnetic storm on 18 July 2005. Cluster C1 simultaneously observed Pc1-2 …
Computing uncertainties in ionosphere-airglow models: II. The Martian airglow
Simon Wedlund, Cyril; Witasse, Olivier; Gronoff, Guillaume +3 more
One of the objectives of spectrometers onboard space missions is to retrieve atmospheric parameters (notably density, composition and temperature). To fulfill this objective, comparisons between observations and model results are necessary. Knowledge of these model uncertainties is therefore necessary, although usually not considered, to estimate …
Spatial distribution of Kelvin-Helmholtz instability at low-latitude boundary layer under different solar wind speed conditions
Wang, C.; Guo, X. C.; Li, W. Y.
Using the PPMLR-MHD global simulation model, we examined the Kelvin-Helmholtz (K-H) instability at the low-latitude boundary layer (LLBL) under northward interplanetary magnetic field (IMF) conditions with various solar wind speeds (400, 600, and 800 km/s). The spatial distribution of the K-H wave power in the equatorial plane shows two distinct p…
Asymmetry in the current sheet and secondary magnetic flux ropes during guide field magnetic reconnection
Fujimoto, M.; Zhang, Tielong; Khotyaintsev, Yuri V. +15 more
A magnetic reconnection event with a moderate guide field encountered by Cluster in the near-Earth tail on 28 August 2002 is reported. The guide field points dawnward during this event. The quadrupolar structure of the Hall magnetic field within the ion diffusion region is distorted toward the northern hemisphere in the earthward part while toward…
Kelvin-Helmholtz instability at Saturn's magnetopause: Cassini ion data analysis
Wilson, R. J.; Delamere, P. A.; Bagenal, F. +1 more
On 13 December 2004 Cassini, on approach to Saturn from the dawn flank, crossed the magnetopause multiple times. During these events the plasma spectrometer had a good field of view of both the magnetospheric and magnetosheath plasmas that often flow in nearly opposite directions (compared with more typical orientations that only allow one regime …
Cassini in Titan's tail: CAPS observations of plasma escape
Lewis, G. R.; Coates, A. J.; Thomsen, M. F. +10 more
We present observations of CAPS electron and ion spectra during Titan distant tail crossings at 5,000-10,000 km altitude by the Cassini spacecraft. In common with closer tail encounters, we identify ionospheric plasma in the tail. Some of the electron spectra indicate a direct magnetic connection to Titan's dayside ionosphere due to the presence o…
The morphology of Saturn's ultraviolet aurora
Carbary, J. F.
Spectrographic images in the far ultraviolet, obtained from observations made from 2007 to 2009, are used to quantify and compare the morphology of Saturn's northern and southern aurora in local time. Made by the UVIS imager on the Cassini spacecraft, these observations differ from previous UV observations of Saturn's aurora by offering complete l…
Survival of flux transfer event (FTE) flux ropes far along the tail magnetopause
Eastwood, J. P.; Fear, R. C.; Phan, T. D. +4 more
During intervals of southward IMF, magnetic reconnection can result in the formation of flux transfer events (FTEs) on the dayside magnetopause which travel along the magnetopause in the anti-sunward direction. Of particular interest is their fate and the role they play transporting solar wind plasma into the magnetosphere. We present the discover…