Search Publications
Determining olivine composition of basaltic dunes in Gale Crater, Mars, from orbit: Awaiting ground truth from Curiosity
Christensen, Philip R.; Lane, Melissa D.
successful landing of the Mars Science Laboratory Curiosity rover in Gale Crater, Mars, presents a rare opportunity for validation of a spectral index developed for determining olivine chemistry from orbital midinfrared remote-sensing data. Here, a spectral index is developed using laboratory emissivity data of 13 synthetic Mg-Fe olivines. Utilizi…
Dependence of O+ escape rate from the Venusian upper atmosphere on IMF directions
Fedorov, A.; Barabash, S.; Futaana, Y. +5 more
investigate the dependence of the O+ escape rate on the upstream interplanetary magnetic field (IMF) direction by using data from the Analyser of Space Plasma and Energetic Atoms (ASPERA-4) instrument and the magnetometer (MAG) onboard Venus Express. We consider two cases, namely the perpendicular IMF case (167 events) and the parallel …
Resonant diffusion of energetic electrons by narrowband Z mode waves in Saturn's inner magnetosphere
Ni, Binbin; Gu, Xudong; Ye, Sheng-Yi +1 more
<title type="main">Abstract<p label="1">Banded emissions near 5 and 20 kHz are observed by the Cassini Radio and Plasma Wave Science (RPWS) instrument and are identified as Z mode waves in the regions where the plasma frequency is below the electron gyrofrequency. Using wave parameters derived from Gaussian fits to the measured power s…
IMF dependence of the azimuthal direction of earthward magnetotail fast flows
Nilsson, H.; Hamrin, M.; Norqvist, P. +2 more
Cluster magnetotail data together with ACE solar wind data from 2001 to 2009 are used to investigate the dependence of the azimuthal flow direction of earthward magnetotail fast flows on the interplanetary magnetic field (IMF). We find an indication that fast flows have favored azimuthal directions that have dependence on the IMF. Our results sugg…
Proton entry into the near-lunar plasma wake for magnetic field aligned flow
Barabash, S.; Futaana, Y.; Wurz, P. +7 more
We report the first observation of protons in the near-lunar (100-200 km from the surface) and deeper (near anti-subsolar point) plasma wake when the interplanetary magnetic field (IMF) and solar wind velocity (vsw) are parallel (aligned flow; angle between IMF and vsw≤10°). More than 98% of the observations during aligned fl…
Orbital radar, imagery, and atmospheric modeling reveal an aeolian origin for Abalos Mensa, Mars
Spiga, A.; Holt, J. W.; Brothers, T. C.
Icy deposits surrounding Planum Boreum, Mars, contain crucial information for deciphering paleoclimate and past geologic processes at the martian north pole. One such deposit, Abalos Mensa, is an enigmatic wedge of material located near the ~ 1 km high Rupes Tenuis. Its unique location and lobate morphology have fostered formation hypotheses that …
Compositional effects in Titan's thermospheric gravity waves
Cui, J.; Müller-Wodarg, I. C. F.; Lian, Y.
In Titan's upper atmosphere, the density profiles of several constituents (N2, CH4, H2, and 29N2) as measured by the Cassini Ion Neutral Mass Spectrometer show periodical structures which we interpret as internal gravity waves. Compositional effects are frequently seen in the data, in which th…
Longitude dependences of Saturn's ultraviolet aurora
Carbary, J. F.
on periodicities in the kilometric radio emissions, the Saturn Longitude System 4 (SLS4) was used to organize the far ultraviolet (120-150 nm) aurora observed by the Ultraviolet Imaging Spectrograph on the Cassini spacecraft. Individual Ultraviolet Imaging Spectrograph pixels were projected onto the ionosphere of Saturn, transformed into the SLS4 …
Saturn's magnetospheric refresh rate
Krupp, N.; Jackman, C. M.; Mitchell, D. G. +3 more
A 2-3 day periodicity observed in Jupiter's magnetosphere (superposed on the giant planet's 9.5 h rotation rate) has been associated with a characteristic mass-loading/unloading period at Jupiter. We follow a method derived by Kronberg et al. (<link href="#grl50530-bib-0016"/>) and find, consistent with their results, that this period is mos…
A large-scale flow vortex in the Venus plasma tail and its fluid dynamic interpretation
Barabash, S.; Lundin, R.; Futaana, Y. +3 more
We report on the existence of a large-scale ion flow vortex, a curled tailward flow of solar wind H+ (SW H+), and ionospheric O+ in the Venus plasma tail. The vortex commences at dusk (-Y), driven by a transverse (to the solar wind) aberration flow component. Dusk magnetosheath and ionospheric ions move westward ac…