Search Publications
Sinuous Aurora at Mars: A Link to the Tail Current Sheet?
Ramstad, Robin; Lillis, Robert J.; Deighan, Justin +18 more
We examine the newly discovered phenomena of sinuous aurora on the nightside of Mars, using images of 130.4 and 135.6 nm oxygen emission measured by the Emirates Mars Mission EMUS ultraviolet spectrograph, and upstream measurements from the MAVEN and Mars Express spacecraft. They are detected in ∼3% of observations, totaling 73 clear detections. T…
Determining the Influence of the IMF and Planetary Magnetic Field Models on Mercury's Magnetosphere Along Spacecraft Trajectories of MESSENGER, BepiColombo and MPO
Heyner, Daniel; Exner, Willi; Griton, Léa. S.
Mercury's planetary magnetic field models (PMFMs) agree on a majorly dipolar field structure with a northward shift of the magnetic equator. However, due to the northerly biased orbit coverage of past spacecraft missions and different data analyzing methods, the available PMFMs differ in the determined multipole magnitudes for the dipole, quadrupo…
Influence of the Jovian Current Sheet Models on the Mapping of the UV Auroral Footprints of Io, Europa, and Ganymede
André, N.; Hue, V.; Rabia, J. +4 more
The in situ characterization of moon-magnetosphere interactions at Jupiter and the mapping of moon auroral footpaths require accurate global models of the magnetospheric magnetic field. In this study, we compare the ability of two widely-used current sheet models, Khurana-2005 (KK2005) and Connerney-2020 (CON2020) combined with the most recent int…
Global Environmental Constraints on Magnetic Reconnection at the Magnetopause From In Situ Measurements
Lavraud, B.; Génot, V.; Jeandet, A. +5 more
Progress in locating the X-line on the magnetopause beyond the atypical due south interplanetary magnetic field (IMF) condition is hampered by the fact that the global plasma and field spatial distributions constraining where reconnection could develop on the magnetopause are poorly known. This work presents global maps of the magnetic shear, curr…
Variation in the Pedersen Conductance Near Jupiter's Main Emission Aurora: Comparison of Hubble Space Telescope and Galileo Measurements
Nichols, J. D.; Vogt, M. F.; Rutala, M. J. +1 more
We present the first large-scale statistical survey of the Jovian main emission (ME) to map auroral properties from their ionospheric locations out into the equatorial plane of the magnetosphere, where they are compared directly to in-situ spacecraft measurements. We use magnetosphere-ionosphere (MI) coupling theory to calculate currents from the …
Parallel Electron Beams at Io: Numerical Simulations of the Dense Plasma Wake
Bagenal, F.; Dols, V.; Paterson, W. R.
In 1995, the Galileo spacecraft traversed the wake of Io at ∼900 km altitude. The instruments onboard detected intense bi-directional field-aligned electron beams (∼140 eV-150 keV), embedded in a dense, cold and slow plasma wake (Nel ∼ 35,000 cm−3, Ti < 10 eV, V < 3 km/s). Similar electron beams were also det…
The April 2023 SYM-H = −233 nT Geomagnetic Storm: A Classical Event
Henri, Pierre; Hajra, Rajkumar; Horne, Richard B. +8 more
The 23-24 April 2023 double-peak (SYM-H intensities of −179 and −233 nT) intense geomagnetic storm was caused by interplanetary magnetic field southward component Bs associated with an interplanetary fast-forward shock-preceded sheath (Bs of 25 nT), followed by a magnetic cloud (MC) (Bs of 33 nT), respectively. The…
Source of the Observed Enhancements in Thermospheric ΣO/N2 During Two Solar Eclipses in 2023
Zhang, Y.; Cantrall, C. E.; Mrak, S. +4 more
Two solar eclipse events in 2023 appeared to produce considerable enhancements in the thermospheric column density ratio of monatomic oxygen to molecular nitrogen (ΣO/N2) as measured by TIMED GUVI. We quantify potential sources for eclipse-induced ΣO/N2 changes and find that the observed enhancements arise from the ionospheri…
On the Contribution of Latitude-Dependent ULF Waves to the Radial Transport of Off-Equatorial Relativistic Electrons in the Radiation Belts
Angelopoulos, Vassilis; Li, Xinlin; Ergun, Robert E. +15 more
Ultra-low frequency (ULF) waves radially diffuse hundreds-keV to few-MeV electrons in the magnetosphere, as the range of drift frequencies of such electrons overlaps with the wave frequencies, leading to resonant interactions. Theoretically this process is described by analytic expressions of the resonant interactions between electrons and ULF wav…
Deep Entry of Low-Energy Ions Into Mercury's Magnetosphere: BepiColombo Mio's Third Flyby Observations
Persson, Moa; Saito, Yoshifumi; Delcourt, Dominique +15 more
Although solar wind-driven convection is expected to dominate magnetospheric circulation at Mercury, its exact pattern remains poorly characterized by observations. Here we present BepiColombo Mio observations during the third Mercury flyby indicative of convection-driven transport of low-energy dense ions into the deep magnetosphere. During the f…