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The Hohmann-Parker effect measured by the Mars Science Laboratory on the transfer from Earth to Mars: Consequences and opportunities
Frahm, R. A.; Wimmer-Schweingruber, R. F.; Christian, E. R. +33 more
We show that a spacecraft launched from Earth towards Mars following a Hohmann minimum energy transfer trajectory has a strong tendency to remain well-connected magnetically to Earth, in the early phase of the transfer, or to Mars in the late phase, via the Parker spiral magnetic field. On the return trip, the spacecraft would remain reasonably we…
Redistribution of lunar polar water to mid-latitudes and its role in forming an OH veneer
Delory, G. T.; Halekas, J. S.; Farrell, W. M. +4 more
We suggest that energization processes like ion sputtering and impact vaporization can eject/release polar water molecules residing within cold trapped regions with sufficient velocity to allow their redistribution to mid-latitudes. We consider the possibility that these polar-ejected molecules can contribution to the water/OH veneer observed as a…
Modeling the seasonal variability of the plasma environment in Saturn's magnetosphere between main rings and Mimas
Johnson, R. E.; Elrod, M. K.; Tseng, W. -L.
The detection of O2+ and O+ ions over Saturn's main rings by the Cassini INMS and CAPS instruments at Saturn orbit insertion (SOI) in 2004 confirmed the existence of the ring atmosphere and ionosphere. The source mechanism was suggested to be primarily photolytic decomposition of water ice producing neutral O2…
Variability in ionospheric total electron content at Mars
Withers, Paul; Kofman, Wlodek; Mendillo, Michael +3 more
The Mars Express (MEX) mission includes a multi-purpose radio instrument called the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS). When used in its ionospheric-penetrating subsurface sounder (SS) radar mode, a by-product of the MARSIS observations is the ray-path-integral of electron densities, called the total electron cont…
Utility of laser altimeter and stereoscopic terrain models: Application to Martian craters
Hynek, Brian M.; Robbins, Stuart J.
The use of numerical datasets of the same type derived from remote sensing instruments is often treated as equivalent in value and utility, within the limits of their spatial resolution. Surface topography is a good example of this. We used gridded digital terrain models (DTMs) derived from both laser altimetry and stereo pairs as well as the orig…
Nighttime photochemical model and night airglow on Venus
Krasnopolsky, Vladimir A.
The photochemical model for the Venus nighttime atmosphere and night airglow (Krasnopolsky, 2010, Icarus 207, 17-27) has been revised to account for the SPICAV detection of the nighttime ozone layer and more detailed spectroscopy and morphology of the OH nightglow. Nighttime chemistry on Venus is induced by fluxes of O, N, H, and Cl with mean hemi…
Saturn's ULF wave foreshock boundary: Cassini observations
Dougherty, M. K.; Mazelle, C.; Bertucci, C. +2 more
Even though the solar wind is highly supersonic, intense ultra-low frequency (ULF) wave activity has been detected in regions just upstream of the bow shocks of magnetized planets. This feature was first observed ahead of the Earth's bow shock, and the corresponding region was called the ULF wave foreshock, which is embedded within the planet's fo…
Young viscous flows in the Lowell crater of Orientale basin, Moon: Impact melts or volcanic eruptions?
Srivastava, N.; Kumar, D.; Gupta, R. P.
Topographical, morphological and spectral reflectance studies have been carried out for a distinct resurface event inside Copernican aged Lowell crater (13.00°S 103.40°W), Orientale basin, using high resolution TC, MI-VIS, LROC-NAC, and M3 data from Kaguya, Lunar Reconnaissance Orbiter (LRO) and Chandrayaan-1 missions. The resurfacing i…
Toroidal and poloidal magnetic fields at Venus. Venus Express observations
Fedorov, A.; Barabash, S.; Lundin, R. +5 more
Magnetic field and plasma measurements carried out onboard Venus Express during solar minimum conditions suggest the existence of two kinds of magnetic field configuration in the Venusian ionosphere. We interpret these as the manifestation of two different types of generation mechanisms for the induced magnetosphere. A different magnetic field top…
Solar wind reflection from the lunar surface: The view from far and near
Barabash, S.; Wurz, P.; McComas, D. J. +7 more
The Moon appears bright in the sky as a source of energetic neutral atoms (ENAs). These ENAs have recently been imaged over a broad energy range both from near the lunar surface, by India's Chandrayaan-1 mission (CH-1), and from a much more distant Earth orbit by NASA's Interstellar Boundary Explorer (IBEX) satellite. Both sets of observations hav…