Search Publications
Massive Multi-Mission Statistical Study and Analytical Modeling of the Earth's Magnetopause: 4. On the Near-Cusp Magnetopause Indentation
Lavraud, B.; Jeandet, A.; Aunai, N. +3 more
The shape and location of the magnetopause current sheet in the near-cusp region is still a debated question. Over time, several observations led to contradictory conclusions regarding the presence of an indentation of the magnetopause in that region. As a result several empirical models consider the surface is indented in that region, while some …
Constraining Europa's Subsolar Atmosphere With a Joint Analysis of HST Spectral Images and Galileo Magnetic Field Data
Saur, J.; Cervantes, S.
We constrain Europa's tenuous atmosphere on the subsolar hemisphere by combining two sets of observations: oxygen emissions at 1,304 and 1,356 Å from Hubble Space Telescope (HST) spectral images and Galileo magnetic field measurements from its closest encounter, the E12 flyby. We describe Europa's atmosphere with three neutral gas species: global …
A 3D Physics-Based Particle Model of the Venus Oxygen Corona: Variations With Solar Activity
Combi, Michael R.; Tenishev, Valeriy; Shou, Yinsi +2 more
Due to Venus not having a substantial planetary magnetic field the fast-flowing solar wind plasma can propagate to regions close to the planet. Therefore, thermal atomic oxygen in the thermosphere, hot oxygen in the corona, and the resulting pickup oxygen ions are essential for determining the overall interaction of the planet with plasma of the a…
A Comparative Study of Magnetic Flux Ropes in the Nightside Induced Magnetosphere of Mars and Venus
Harada, Yuki; Huang, Zesen; Luhmann, Janet G. +4 more
We analyzed Mars Atmosphere and Volatile Evolution (MAVEN) and Venus Express (VEX) data of magnetic flux ropes observed in both Mars and Venus nightside induced magnetosphere, in order to understand their statistical characteristics and possible formation processes. We statistically identified 382 (286) events at Mars (Venus) via the minimum varia…
Dawn-Dusk Ion Flow Asymmetry in the Plasma Sheet: Interplanetary Magnetic Field By Versus Distance With Respect to the Neutral Sheet
Hamrin, M.; Pitkänen, T.; Chong, Ghai Siung +1 more
Previous studies have shown that the average dawn-dusk component of the perpendicular plasma flow in the plasma sheet (V⊥) can vary depending on the distance relative to the neutral sheet and the dawn-dusk component of the interplanetary magnetic field (IMF By). In this study, we combined 33 years of data from the Geotail, Ti…
Nightside Auroral Electrons at Mars: Upstream Drivers and Ionospheric Impact
Liemohn, Michael W.; Mazelle, Christian; Xu, Shaosui +12 more
Discrete aurorae have been observed at Mars by multiple spacecraft, including Mars Express, Mars Atmosphere and Volatile EvolutioN (MAVEN), and most recently the United Arab Emirates Hope spacecraft. Meanwhile, there have been studies on the source particles responsible for producing these detectable aurorae (termed "auroral electrons"). By utiliz…
Study of Slow-Mode Shock Formation and Particle Acceleration in the Symmetric Magnetic Reconnection Based on Hybrid Simulations
Seki, K.; Amano, T.; Walia, N. K.
The structure of the magnetic reconnection region and the acceleration mechanism of particles as they traverse from upstream into the reconnection exhaust are explored using 2.5D hybrid simulations. The reconnection boundary was analyzed using the Rankine-Hugoniot conditions and the six specific conditions for slow-mode shocks. We observe that the…
A Review of Cluster Wideband Data Multi-Spacecraft Observations of Auroral Kilometric Radiation
Pickett, J. S.; Yearby, K. H.
We review important advances in the understanding of auroral kilometric radiation (AKR) resulting from observations by the Wideband Data instruments on the four Cluster spacecraft. AKR is an intense radio emission originating in the Earth's auroral regions with frequencies typically in the range 50-700 kHz, usually observed from space. It is now w…
South Pole Station Ground-Based and Cluster Satellite Measurements of Leaked and Escaping Auroral Kilometric Radiation
Yearby, Keith; Pickett, Jolene S.; LaBelle, James
Previous work suggests that Auroral Kilometric Radiation (AKR) leaks to low altitudes. To investigate this phenomenon, wideband wave measurements have been conducted simultaneously at South Pole, Antarctica, and at the Cluster satellites, during 35 intervals in 2018-2020. Leaked AKR is observed ∼5% of the time at South Pole and escaping AKR ∼31% o…
The Helicity Sign of Flux Transfer Event Flux Ropes and Its Relationship to the Guide Field and Hall Physics in Magnetic Reconnection at the Magnetopause
Lavraud, B.; Génot, V.; Chen, Y. +13 more
Flux Transfer Events (FTEs) are transient magnetic flux ropes typically found at the Earth's magnetopause on the dayside. While it is known that FTEs are generated by magnetic reconnection, it remains unclear how the details of magnetic reconnection controls their properties. A recent study showed that the helicity sign of FTEs positively correlat…