Search Publications
Excitation of Saturnian ECH Waves Within Remote Plasma Injections: Cassini Observations
Ni, Binbin; Gu, Xudong; Cao, Xing +7 more
Based on Cassini observations, we report representative electrostatic electron cyclotron harmonic (ECH) wave events observed in Saturn's magnetosphere within remote plasma injections. Unlike local injections, remote injections are "older" injection events that have evolved to form a dispersed signature in particle energy spectrum. We show that Sat…
A Tectonic Origin for the Largest Marsquake Observed by InSight
Wilson, Colin; Lucas, Antoine; Tirsch, Daniela +23 more
The S1222a marsquake detected by InSight on 4 May 2022 was the largest of the mission, at MwMa 4.7. Given its resemblance to two other large seismic events (S1000a and S1094b), which were associated with the formation of fresh craters, we undertook a search for a fresh crater associated with S1222a. Such a crater would be exp…
Solar Control of the Pickup Ion Plume in the Dayside Magnetosheath of Venus
Xu, Qi; Zuo, Pingbing; Xu, Xiaojun +3 more
Using the 8.5-year Venus Express measurements, we demonstrate the asymmetric plasma distributions in the Venusian magnetosheath. An escaping plume is formed by pickup oxygen ions in the hemisphere where the motional electric field points outward from Venus, while the velocity of solar wind protons is faster in the opposite hemisphere. The pickup O…
Electron Rolling-Pin Distributions Preceding Dipolarization Fronts
Cao, J. B.; Liu, C. M.; Xing, X. N.
Electron rolling-pin distribution (RPDs), characterized by triple peaks at pitch angles 0°, 90°, and 180°, have recently been discovered in the terrestrial magnetosphere. Since the RPDs' formation is typically attributed to local betatron acceleration, RPDs have been believed to appear primarily inside strong magnetic regions, such as flux pileup …
Global Spatial Distribution of Hack's Law Exponent on Mars Consistent With Early Arid Climate
Luo, W.; Howard, A. D.; Craddock, R. A. +2 more
Widespread valley networks (VNs) on Mars and other evidence point to an early warm and wet climate. However, ongoing debates still exist about VN's formation processes and associated climatic conditions. The power law relationship between basin length and area (Hack's Law) can be diagnostic of different fluvial processes related to climatic condit…
Simultaneous Mesoscale Polar Cusp Field-Aligned Currents Measured on Mid- and Low-Altitude Satellites
Dunlop, M. W.; Dong, X. -C.; Xiao, C. +3 more
Using a conjunction of Cluster in the mid-altitude dayside magnetosphere and Swarm in the low-altitude ionosphere, we show, by employing multi-spacecraft analysis, that matched, strong magnetic perturbations and the corresponding mesoscale field-aligned current (FAC) structures are measured in the high latitude polar cusp region during the 7 Octob…
Multispacecraft Observations of the Simultaneous Occurrence of Magnetic Reconnection at High and Low Latitudes During the Passage of a Solar Wind Rotational Discontinuity Embedded in the April 9-11, 2015 ICME
Lugaz, Noé; Escoubet, C. Philippe; Wing, Simon +2 more
Numerous questions remain about how solar wind directional discontinuities, for example, rotational discontinuities (RDs), affect energy and transport processes at the magnetopause. The impact on the dayside magnetosphere of a solar wind RD is studied. The study shows that the RD leads to complex structures at the magnetopause, boundary layer, man…
Undulated Shock Surface Formed After a Shock-Discontinuity Interaction
Shen, Chao; Zhou, Yufei; Ji, Yong
Shock ripples and shock-discontinuity interactions (SDIs) have long been proposed to explain the frequent occurrence of high-speed jets (HSJs) in the magnetosheath; however, there is no direct observational evidence for either of them occurring near a shock. Herein, we report a large-scale, long-duration undulated quasi-perpendicular shock surface…
Jovian Magnetospheric Injections Observed by the Hubble Space Telescope and Juno
Wilson, R. J.; Bagenal, F.; Orton, G. S. +13 more
We compare Hubble Space Telescope observations of Jupiter's FUV auroras with contemporaneous conjugate Juno in situ observations in the equatorial middle magnetosphere of Jupiter. We show that bright patches on and equatorward of the main emission are associated with hot plasma injections driven by ongoing active magnetospheric convection. During …
A Survey of Strong Electric Potential Drops in the Ionosphere of Venus
Zhang, Tielong; Futaana, Yoshifumi; Collinson, Glyn A. +6 more
Every planet or moon with an ionosphere is thought to generate a weak electrical potential which helps ions overcome gravity and escape to space. A pilot study at Venus by Collinson et al. (2016, https://doi.org/10.1002/2016GL068327) indicated a planetary potential an order of magnitude stronger t…