Search Publications
The force-free configuration of flux ropes in geomagnetotail: Cluster observations
Rème, H.; Dunlop, M.; Liu, Z. X. +7 more
Unambiguous knowledge of magnetic field structure and the electric current distribution is critical for understanding the origin, evolution, and related dynamic properties of magnetic flux ropes (MFRs). In this paper, a survey of 13 MFRs in the Earth's magnetotail are conducted by Cluster multipoint analysis, so that their force-free feature, i.e.…
Dependence of IMF By penetration into the neutral sheet on IMF Bz and geomagnetic activity
Dunlop, M.; Cao, JinBin; Duan, Aiying +2 more
The penetration of interplanetary magnetic field (IMF) By into the magnetosphere plays an important role in determining magnetospheric configuration and its dynamics. In this paper, using 9 years of Cluster data at the center of neutral sheet, we statistically study the relations of the penetration of IMF By in the neutral sh…
Saturn's dayside ultraviolet auroras: Evidence for morphological dependence on the direction of the upstream interplanetary magnetic field
Lewis, G. R.; Dougherty, M. K.; Alexeev, I. I. +6 more
We examine a unique data set from seven Hubble Space Telescope (HST) "visits" that imaged Saturn's northern dayside ultraviolet emissions exhibiting usual circumpolar "auroral oval" morphologies, during which Cassini measured the interplanetary magnetic field (IMF) upstream of Saturn's bow shock over intervals of several hours. The auroras general…
Electron density inside Enceladus plume inferred from plasma oscillations excited by dust impacts
Gurnett, D. A.; Kurth, W. S.; Wahlund, J. -E. +4 more
Enceladus' southern plume is one of the major discoveries of the Cassini mission. The water neutrals and water ice particles (dust) ejected by the cryovolcanic activity populate Saturn's E ring and the neutral torus, and they interact with the plasma environment of Saturn's magnetosphere. The plasma neutrality inside Enceladus' plume has been show…
Flapping current sheet with superposed waves seen in space and on the ground
Zhang, T. L.; Nakamura, R.; Volwerk, M. +4 more
A wavy current sheet event observed on 15 October 2004 between 1235 and 1300 UT has been studied by using Cluster and ground-based magnetometer data. Waves propagating from the tail center to the duskside flank with a period ~30 s and wavelength ~1 RE are superimposed on a flapping current sheet, accompanied with a bursty bulk flow. Thr…
A survey of hot flow anomalies at Venus
Coates, A. J.; Fedorov, A.; Barabash, S. +10 more
We present the first survey of hot flow anomalies (HFAs) at the bow shock of Venus, expanding on our recent initial case study. A 3.06 sol (774 Earth day) survey of Venus Express magnetometer, ion spectrometer, and electron spectrometer data was undertaken in order to identify Cytherian HFAs. Seven events were discovered, corresponding to a statis…
Evidence for the braking of flow bursts as they propagate toward the Earth
Dandouras, I.; Nilsson, H.; André, M. +9 more
In this article we use energy conversion arguments to investigate the possible braking of flow bursts as they propagate toward the Earth. By using E·J data (E and J are the electric field and the current density) observed by Cluster in the magnetotail plasma sheet, we find indications of a plasma deceleration in the region -20 RE < X…
Backscattered energetic neutral atoms from the Moon in the Earth's plasma sheet observed by Chandarayaan-1/Sub-keV Atom Reflecting Analyzer instrument
Barabash, Stas; Futaana, Yoshifumi; Wieser, Martin +8 more
We present the observations of energetic neutral atoms (ENAs) produced at the lunar surface in the Earth's magnetotail. When the Moon was located in the terrestrial plasma sheet, Chandrayaan-1 Energetic Neutrals Analyzer (CENA) detected hydrogen ENAs from the Moon. Analysis of the data from CENA together with the Solar Wind Monitor (SWIM) onboard …
MARSIS observations of the Martian nightside ionosphere dependence on solar wind conditions
Gurnett, D. A.; Němec, F.; Morgan, D. D. +1 more
Despite the absence of solar radiation on the Martian nightside, a weak, irregular, and variable ionosphere is produced there. The nightside ionosphere is thought to be maintained by two main sources: dayside-nightside plasma transport and electron precipitation. Observations by Mars Express (MEX) and Mars Global Surveyor (MGS) have shown that the…
Modeling radiation belt electron acceleration by ULF fast mode waves, launched by solar wind dynamic pressure fluctuations
Zong, Q. -G.; Rankin, R.; Degeling, A. W.
We investigate the magnetospheric MHD and energetic electron response to a Storm Sudden Commencement (SSC) and subsequent magnetopause buffeting, focusing on an interval following an SSC event on 25 November 2001. We find that the electron flux signatures observed by LANL, Cluster, and GOES spacecraft during this event can largely be reproduced us…