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Observations of HCl altitude dependence and temporal variation in the 70-100 km mesosphere of Venus
Clancy, R. Todd; Sandor, Brad J.
Spectroscopically resolved observations of the 625.9 GHz H35Cl absorption lines were obtained with the James Clerk Maxwell Telescope on October 23, November 7, and December 5, 2010. The nightside atmosphere was observed on all three dates, and the dayside morning crescent was also observed on December 5. Shape of the pressure-broadened …
The impact of a weak south pole on thermal convection in Enceladus’ ice shell
Showman, Adam P.; Tobie, Gabriel; Han, Lijie
Enceladus exhibits a strong hemispheric dichotomy of tectonism and heat flux, with geologically young, heavily tectonized terrains and a high heat flux in the South Polar Terrain (SPT) and relatively ancient terrains with presumably lower heat fluxes over the rest of the satellite. To understand the convective pattern and its relationship with sur…
Dielectric constant estimation of the uppermost Basal Unit layer in the martian Boreales Scopuli region
Orosei, Roberto; Pettinelli, Elena; Mattei, Elisabetta +3 more
An electromagnetic inversion model has been applied to echoes from the subsurface sounding Shallow Radar (SHARAD) to retrieve the dielectric properties of the uppermost Basal Unit (BU) beneath the North Polar Layered Deposits of Mars. SHARAD data have been carefully selected to satisfy the assumption of the inversion model which requires a stratig…
Rotation period of Venus estimated from Venus Express VIRTIS images and Magellan altimetry
Erard, S.; Drossart, P.; Piccioni, G. +2 more
The 1.02 µm wavelength thermal emission of the nightside of Venus is strongly anti-correlated to the elevation of the surface. The VIRTIS instrument on Venus Express has mapped this emission and therefore gives evidence for the orientation of Venus between 2006 and 2008. The Magellan mission provided a global altimetry data set recorded betw…
Post-equinox dynamics and polar cloud structure on Uranus
Sromovsky, L. A.; Fry, P. M.; Hammel, H. B. +2 more
Post equinox imaging of Uranus by HST, Keck, and Gemini telescopes has enabled new measurements of winds over previously sampled latitudes as well as measurements at high northern latitudes that have recently come into better view. These new observations also used techniques to greatly improve signal to noise ratios, making possible the detection …
The three-dimensional structure of Saturn's E ring
Hedman, M. M.; Burns, J. A.; Hamilton, D. P. +1 more
Saturn's diffuse E ring consists of many tiny (micron and sub-micron) grains of water ice distributed between the orbits of Mimas and Titan. Various gravitational and non-gravitational forces perturb these particles' orbits, causing the ring's local particle density to vary noticeably with distance from the planet, height above the ring-plane, hou…
Small-scale variability in Saturn’s lower ionosphere
Matcheva, Katia I.; Barrow, Daniel J.
We perform and present a wavelet analysis on all 31 Cassini electron density profiles published to date (Nagy, A.F. et al. [2006]. J. Geophys. Res. 111 (A6), CiteID A06310; Kliore, A.J. et al. [2009]. J. Geophys. Res. 114 (A4), CiteID A04315). We detect several discrete scales of variability present in the observations. Small-scale variability (S …
Energetic electron observations of Rhea’s magnetospheric interaction
Gurnett, D. A.; Persoon, A. M.; Krupp, N. +12 more
Saturn’s moon Rhea is thought to be a simple plasma absorber, however, energetic particle observations in its vicinity show a variety of unexpected and complex interaction features that do not conform with our current understanding about plasma absorbing interactions. Energetic electron data are especially interesting, as they contain a series of …
Sublimation-driven erosion on Hyperion: Topographic analysis and landform simulation model tests
Schenk, Paul M.; White, Oliver L.; Moore, Jeffrey M. +2 more
The unique appearance of Hyperion can be explained in part by the loss to space of ballistic ejecta during impact events, as was proposed by Thomas et al. (Thomas, P.C. et al. [2007a]. Icarus 190, 573-584). We conclude that such loss is a partial explanation, accounting for the lack of appreciable intercrater plains on a saturation-cratered surfac…
Characterizing Io’s Pele, Tvashtar and Pillan plumes: Lessons learned from Hubble
Spencer, John R.; Jessup, Kandis Lea
Hubble Space Telescope/Wide Field and Planetary Camera 2 (HST/WFPC2) images of Io obtained between 1995 and 2007 between 0.24 and 0.42 µm led to the detection of the Pele plume in reflected sunlight in 1995 and 1999; imaging of the Pele plume via absorption of jovian light in 1996 and 1999; detection of the Prometheus-type Pillan plume in re…