Search Publications
Production of N2 Vegard-Kaplan and other triplet band emissions in the dayglow of Titan
Bhardwaj, Anil; Jain, Sonal Kumar
Recently the Cassini Ultraviolet Imaging Spectrograph (UVIS) has revealed the presence of N2 Vegard-Kaplan (VK) band A3Σu+-X1Σg+ emissions in Titan's dayglow limb observation. We present model calculations for the production of various N2 triplet states (viz., A3Σu+,B3Πg,…
Mid-infrared spectra of differentiated meteorites (achondrites): Comparison with astronomical observations of dust in protoplanetary and debris disks
Koike, Chiyoe; Mason, Andrew; Morlok, Andreas +4 more
Mid-infrared (5-25 µm) transmission/absorption spectra of differentiated meteorites (achondrites) were measured to permit comparison with astronomical observations of dust in different stages of evolution of young stellar objects. In contrast to primitive chondrites, achondrites underwent heavy metamorphism and/or extensive melting and repre…
Spectral analysis and geological mapping of the Daedalia Planum lava field (Mars) using OMEGA data
Massironi, M.; Giacomini, L.; Carli, C. +1 more
The great variety of morphologies observed in the Daedalia Planum lava flows (Mars) encouraged a detailed study of their spectral characteristics, in order to obtain information about lava composition and detect possible differences in the spectra of the flows. The OMEGA spectral data collected from the lava field appear rather similar, with absor…
Regolith grain sizes of Saturn’s rings inferred from Cassini-CIRS far-infrared spectra
Spilker, Linda; Morishima, Ryuji; Edgington, Scott G.
We analyze far-infrared (10-650 cm-1) emissivity spectra of Saturn’s main rings obtained by the Cassini Composite Infrared Spectrometer (CIRS). In modeling of the spectra, the single scattering albedos of regolith grains are calculated using the Mie theory, diffraction is removed with the delta-Eddington approximation, and the hemispher…
Compositional analysis of Hyperion with the Cassini Visual and Infrared Mapping Spectrometer
Clark, Roger N.; Cruikshank, Dale P.; Brad Dalton, J.
Compositional mapping of the surface of Hyperion using Cassini Visual and Infrared Mapping Spectrometer (VIMS) observations reveals a heterogeneous surface dominated by water ice accompanied by additional materials. Carbon dioxide, as evidenced by a prominent absorption band centered at 4.26 µm, is distributed over most of the surface, inclu…
The electromagnetic pickup of submicron-sized dust above Enceladus's northern hemisphere
Gurnett, Donald A.; Farrell, William M.; Kurth, William S. +3 more
As the saturnian magnetoplasma sweeps past Enceladus, it experiences both a decrease in electron content and sharp slowdown in the northern hemisphere region within ∼5 Enceladus Radii (Re). This slowdown is observed by Cassini in regions not obviously associated with the southern directed plume-originating ions. We suggest herein that t…
Investigating magnetospheric interaction effects on Titan's ionosphere with the Cassini orbiter Ion Neutral Mass Spectrometer, Langmuir Probe and magnetometer observations during targeted flybys
Luhmann, J. G.; Russell, C. T.; Dougherty, M. K. +13 more
In the ∼6 years since the Cassini spacecraft went into orbit around Saturn in 2004, roughly a dozen Titan flybys have occurred for which the Ion Neutral Mass Spectrometer (INMS) measured that moon's ionospheric density and composition. For these, and for the majority of the ∼60 close flybys probing to altitudes down to ∼950 km, Langmuir Probe elec…
Large-scale deformational systems in the South Polar Layered Deposits (Promethei Lingula, Mars): "Soft-sediment" and Deep-Seated Gravitational Slope Deformations Mechanisms
Marinangeli, Lucia; Guallini, Luca; Brozzetti, Francesco
The present study is the first attempt at a detailed structural and kinematic analysis of large-scale deformational systems observed in the South Polar Layered Deposits (SPLDs) in the Promethei Lingula (PL) margins (Mars). By systematically collecting attitude data referable to previously unknown deformational structures and defining the cross-cut…
The vertical distribution of the Venus NO nightglow: Limb profiles inversion and one-dimensional modeling
Bertaux, J. -L.; Gérard, J. -C.; Soret, L. +2 more
Ultraviolet (UV) spectra of the δ (190-240 nm) and γ (225-270 nm) bands of the nitric oxide (NO) molecule have been measured on the nightside of the atmosphere of Venus with the Spectroscopy for Investigation of Characteristics of the Atmosphere of Venus (SPICAV) instrument on board Venus Express (VEX). Excited NO molecules on the nightside of the…
O/O 2 emissions in the Venus nightglow
Chanover, Nancy J.; Bida, Thomas A.; Slanger, Tom G. +1 more
The oxygen green line is one of the most characteristic features in the terrestrial visible nightglow; it can be seen in the Venus nightglow, but with much greater intensity variation than in the terrestrial case. Here we synthesize our current understanding of the green line in the Venus nightglow and discuss what might be expected observationall…