Search Publications
First Observation of the Oxygen 630 nm Emission in the Martian Dayglow
Aoki, S.; Vandaele, A. C.; Daerden, F. +13 more
Following the recent detection of the oxygen green line airglow on Mars, we have improved the statistical analysis of the data recorded by the NOMAD/UVIS instrument on board the ExoMars Trace Gas Orbiter mission by summing up hundreds of spectra to increase the signal to noise ratio. This led to the observation of the OI 630 nm emission, the first…
Magnetic Topology at Venus: New Insights Into the Venus Plasma Environment
Xu, Shaosui; Frahm, Rudy A.; Luhmann, Janet G. +2 more
This study provides the first characterization of magnetic topology (i.e., the magnetic connectivity to the collisional ionosphere) at Venus, which might give new insights into the Venusian space environment on topics such as the penetration of the interplanetary magnetic field (IMF) into the ionosphere, planetary ion outflow and inflow, and auror…
Alternatives to Liquid Water Beneath the South Polar Ice Cap of Mars
Steinbrügge, Gregor; Schroeder, Dustin M.
Radar sounding of Mars' south polar ice cap has revealed portions of its base with stronger radar returns than its surface. These have been used to estimate high real permittivity values consistent with liquid water. However, the thermal, chemical, and geological conditions required to sustain such water bodies are challenging to achieve in the co…
Active Boulder Falls in Terra Sirenum, Mars: Constraints on Timing and Causes
Conway, Susan J.; Grindrod, Peter M.; Davis, Joel M. +1 more
We use time series images to identify significant active boulder falls in an impact crater on Mars. Evidence for active boulder falls include boulder trails with impact marks from bouncing and rolling, and dark patches from boulder impacts away from the base of the crater walls. We were able to define three time periods with active boulder falls a…
Jupiter's Double-Arc Aurora as a Signature of Magnetic Reconnection: Simultaneous Observations From HST and Juno
Wei, Y.; Bonfond, B.; Vogt, M. F. +10 more
Jupiter's powerful auroral emission is usually divided into the polar, main, and equatorward components. The driver of Jupiter's main aurora is a central question for the community. Previous investigations reveal many distinct substructures on the main auroral oval, which are indicators of fundamentally different magnetospheric processes. Understa…
Subion-Scale Flux Rope Nested Inside Ion-Scale Flux Rope in Earth's Magnetotail
Wang, Z.; Liu, Y. Y.; Fu, H. S. +2 more
Magnetic flux ropes (MFRs)—transient magnetic structures widely observed in Earth's magnetosphere—play crucial roles in particle acceleration and energy dissipation. MFRs above ion scale have been well studied, while MFRs at subion scales and their coupling with larger-scale ropes still remains not well understood. In this paper, we present the fi…
Double Peak Structures of Martian Nightside Total Electron Content in Strong Crustal Magnetic Cusp Regions
Futaana, Yoshifumi; Nielsen, Erling; Qin, JunFeng +4 more
With the help of the high spatial resolution total electron content (TEC) data obtained by Mars Advanced Radar for Subsurface and Ionospheric Sounding on board the Mars Express (MEx) during June 2005 to September 2007, the detailed configurations of the Martian nightside ionosphere in crustal magnetic field cusp regions are researched in this pape…
The Statistical Morphology of Saturn's Equatorial Energetic Neutral Atom Emission
Mitchell, D. G.; Paranicas, C.; Badman, S. V. +6 more
Saturn's magnetosphere is an efficient emitter of energetic neutral atoms (ENAs), created through charge exchange of energetic ions with the extended neutral cloud originating from the icy moon Enceladus. We present an analysis using the complete image set captured by Cassini's Ion Neutral Camera to characterize Saturn's average ENA morphology. Co…
Was Gale Crater (Mars) Connected to a Regionally Extensive Groundwater System?
Horvath, D. G.; Roseborough, V.; Palucis, M. C.
Gale crater, home of the Curiosity rover, contains some of the best geomorphic and sedimentologic evidence on Mars for large lakes during the Hesperian and Amazonian. Orbital data and rover observations of delta deposits and terminations of gully networks suggest several phases of stable lake levels. However, the regional extent, water source (gro…
On the Persistent Poloidal Alfven Waves
Choi, Jiwon; Lee, Dong-Hun
Standing poloidal Alfven waves, radial oscillations with ultralow frequency of 5-20 mHz, are excited by wave-particle interaction in the magnetosphere. It has been a question over several decades why poloidal oscillations often persist and are not quickly converted into toroidal waves even when there is no corresponding particle source. By adoptin…