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This response is to address some of the comments made by Dr. Fox and also to clarify some points in the Bakalian [2006. Icarus 183, 69–73] and Bakalian and Hartle [2006. Icarus 183, 55–68] papers. It is regrettable that some of the statements in the Bakalian and Bakalian and Hartle papers were misinterpreted.
The number of known spin vectors of main belt and near-Earth asteroids is regularly growing, including new objects, and updating the estimates concerning known cases, with the aid of new observations and of improved observational techniques. A reliable statistical analysis of the spin vectors is now possible. In general the poles (both for MB bodies and for NEAs) are not isotropically distributed,...
Over the last 15 to 20 years several high quality, high resolution data have been taken with the very large array (VLA). These data exhibit a wide range of ring opening angles (|B|=0 to 26°) and wavelengths (λ=0.7 to 20 cm). At these wavelengths the primary flux from the rings is scattered saturnian thermal emission, with a small contribution coming from the ring particles' own thermal emission. Much...
Geophysical data have led to the interpretation that Beta Regio, a 2000×25000 km wide topographic rise with associated rifting and volcanism, formed due to the rise of a hot mantle diapir interpreted to be caused by a mantle plume. We have tested this hypothesis through detailed geologic mapping of the V-17 quadrangle, which includes a significant part of the Beta Regio rise, and reconnaissance mapping...
On August 11, 2004, we made adaptive optics observations of the Uranus and Neptune systems with the Keck II Near Infrared Camera. Uranus and Triton were observed in three broadband filters (J, H, and K-prime) and four narrowband filters [Hcont, FeII, He1_B, and H2(v=1-0)]. Miranda, Ariel, Umbriel, and Oberon were observed in the four narrowband filters only. To achieve the highest possible photometric...
We investigate the dynamical evolution of trans-neptunian objects (TNOs) in typical scattered disk orbits (scattered TNOs) by performing simulations using several thousand particles lying initially on Neptune-encountering orbits. We explore the role of resonance sticking in the scattered disk, a phenomenon characterized by multiple temporary resonance captures (‘resonances’ refers to external mean...
In February 2003, March 2003 and January 2004 Pele plume transmission spectra were obtained during Jupiter transit with Hubble's Space Telescope Imaging Spectrograph (STIS), using the 0.1″ wide slit and the G230LB grating. The STIS spectra covered the 2100–3100 Å wavelength regions and extended spatially along Io's limb encompassing the region directly above and northward of the vent of the Pele volcano...
We have constructed synthetic solar spectra for the 2302–4800 cm −1 (2.08–4.34 μm) range, a spectral range where planetary objects mainly emit reflected sunlight, using ATMOS (Atmospheric Trace Molecule Spectroscopy)/Spacelab-3 and Atlas-3 spectra, of which resolution is 0.01 cm −1 . We adopted Voigt line profiles for the modeling of line shapes based on an atlas of line identifications...
The Cassini Titan Radar mapper has observed elevated blocks and ridge-forming block chains on Saturn's moon Titan demonstrating high topography we term “mountains.” Summit flanks measured from the T3 (February 2005) and T8 (October 2005) flybys have a mean maximum slope of 37° and total elevations up to 1930 m as derived from a shape-from-shading model corrected for the probable effects of image resolution...
A new method is presented for estimating crustal thickness from gravity and topography data on the Moon. By calculating analytically the exterior gravitational field for a set of arbitrarily shaped polyhedra, relief along the crust–mantle interface can be inverted for that satisfies the observational constraints. As this method does not rely upon filtering the Bouguer anomaly, which was required with...
Regions near Enceladus' equator, Sarandib and Diyar Planitia, contain extensive sets of parallel ridges and troughs that may be diagnostic of the region's formation conditions. We present photoclinometry profiles across these ridges and troughs, which indicate that they are periodic, low-slope features with dominant wavelengths of 3 to 4 km and amplitudes between 100 and 400 m. The morphology of these...
The known extrasolar planets exhibit a wide range of orbital eccentricities e. This has a profound influence on their rotations and climates. Because of tides in their interiors, mostly solid exoplanets are expected eventually to despin to a state of spin-orbit resonance, where the orbital period is some integer or half-integer times the rotation period. The most important of these resonances is the...
We study the conductivity distribution inside Europa by using a time-dependent 3D-model of the temporal periodic interaction between Europa and the jovian magnetosphere. The temporal variations are caused by periodic variations of the magnetospheric plasma and magnetic fields at Europa. We develop a model which describes simultaneously the 3D plasma interaction of Europa's atmosphere with Jupiter's...
New mapping reveals 100 probable impact craters on Triton wider than 5 km diameter. All of the probable craters are within 90° of the apex of Triton's orbital motion (i.e., all are on the leading hemisphere) and have a cosine density distribution with respect to the apex. This spatial distribution is difficult to reconcile with a heliocentric (Sun-orbiting) source of impactors, be it ecliptic comets,...
The aim of this work is to understand the absence of objects along the orbits of Mimas and Enceladus in contrast to their presence at the orbits of neighbouring Tethys and Dione from the point of view of dynamical stability. Large scale numerical simulations of 360 test particles within the coorbital regions of these four saturnian satellites were carried out for 4×105 yr or 1.6×108 revolutions of...
In recent articles published in Icarus, Bakalian [2006. Icarus 183, 69–78] discusses and computes the production rates of hot nitrogen atoms in the martian thermosphere due to N 2 photodissociation and N +2 dissociative recombination, and Bakalian and Hartle [2006. Icarus 183, 55–68] use a Monte Carlo code to compute the escape rates of nitrogen atoms from Mars due to photodissociation...
A total of 56 non-porphyritic pyroxene and pyroxene/olivine micro-objects from different unequilibrated ordinary chondrites were selected for detailed studies to test the existing formation models. Our studies imply that the non-porphyritic objects represent quickly quenched liquids with each object reflecting a very complex and unique evolutionary history. Bulk major element analyses, obtained with...
The Antarctic Dry Valleys (ADV) are generally classified as a hyper-arid, cold-polar desert. The region has long been considered an important terrestrial analog for Mars because of its generally cold and dry climate and because it contains a suite of landforms at macro-, meso-, and microscales that closely resemble those occurring on the martian surface. The extreme hyperaridity of both Mars and the...
The Thermal Emission Spectrometer aboard the Mars Global Surveyor spacecraft has produced an extensive atmospheric data set, beginning during aerobraking and continuing throughout the extended scientific mapping phase. Temperature profiles for the atmosphere below about 40 km, surface temperatures and total dust and water ice opacities, can be retrieved from infrared spectra in nadir viewing mode...
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