Megabarchans on Mars

Abstract not available

Preliminary results from a new study of transverse aeolian ridges (TARS) on Mars

Abstract not available

Regolith-atmosphere exchange of water in Mars' recent past

We investigate the exchange of water vapour between the regolith and atmosphere of Mars, and how it varies with different orbital parameters, atmospheric dust contents and surface water ice reservoirs. This is achieved through the coupling of a global circulation model (GCM) and a regolith diffusion model. GCM simulations are performed for hundreds of Mars years, with additional one-dimensional simulations performed for 50 kyr. At obliquities ε = 15° and 30°, the thermal inertia and albedo of the regolith have more control on the subsurface water distribution than changes to the eccentricity or solar longitude of perihelion. At ε = 45°, atmospheric water vapour abundances become much larger, allowing stable subsurface ice to form in the tropics and mid-latitudes. The circulation of the atmosphere is important in producing the subsurface water distribution, with increased water content in various locations due to vapour transport by topographically-steered flows and stationary waves. As these circulation patterns are due to topographic features, it is likely the same regions will also experience locally large amounts of subsurface water at different epochs. The dustiness of the atmosphere plays an important role in the distribution of subsurface water, with a dusty atmosphere resulting in a wetter water cycle and increased stability of subsurface ice deposits

Investigating the Martian atmosphere using the ExoMars 2016 lander

Accurate modelling of the Martian atmosphere is essential both for planning and completing future missions to the Martian surface, and for accurate analysis and interpretation of the data that they return. Large dust storms and local wind patterns can affect spacecraft landing profiles, and the level of dust present in the atmosphere may impact lander performance. The ExoMars 2016 Mission will carry an Entry, Descent and Landing Demonstrator Module (EDM), primarily designed to test the ability of ESA’s lander technology to carry a science package to the surface [1]. The Atmospheric Mars Entry and Landing Investigations and Analysis (AMELIA) team [2] will use the module’s entry and descent trajectory to characterise the structure of the atmosphere along the travelled landing profile, and to determine properties of the atmosphere, such as density and wind speed, over a wide altitude range from the upper atmosphere to the surface. Aerosol abundances, including atmospheric dust, will also be characterised. These combined datasets will enable more accurate predictions of the atmospheric environment that future landers will encounter. EDM’s surface science package, DREAMS (Dust characterisation, Risk assessment, and Environment Analyser on the Martian Surface), includes sensors to measure wind speed and direction, surface temperature, pressure, and the amount of atmospheric dust present near the surface [3]. We will use the descent and surface profile data collected by EDM to verify and improve current Martian atmospheric modelling completed at The Open University, using both the global circulation and mesoscale models. [1] Forget et al. (2011) Fourth International Workshop on the Mars Atmosphere: Modeling and Observations, Paris. [2] Ferri et al. (2012) 9th International Planetary Probe Workshop (IPPW9), Toulouse. [3] Esposito et al. (2013) EPSC Abstracts Vol. 8, EPSC2013-815

Small-scale morphologic properties of martian gullies: insights from analysis of HiRISE images

Abstract not available

The distribution of Transverse Aeolian Ridges on Mars

Abstract not available

Preliminary findings from geological mapping of the Hokusai (H5) quadrangle of Mercury

Quadrangle geological maps from Mariner 10 data cover 45% of the surface of Mercury at 1:5M scale. Orbital MESSENGER data, which cover the entire planetary surface, can now be used to produce finer scale geological maps, including regions unseen by Mariner 10. Hokusai quadrangle (0–90° E; 22.5–66° N) is in the hemisphere unmapped by Mariner 10. It contains prominent features which are already being studied, including: Rachmaninoff basin, volcanic vents within and around Rachmaninoff, much of the Northern Plains and abundant wrinkle ridges. Its northern latitude makes it a prime candidate for regional geological mapping since compositional and topographical data, as well as Mercury Dual Imaging System (MDIS) data, are available for geological interpretation. This work aims to produce a map at 1:2M scale, compatible with other new quadrangle maps and to complement a global map now in progress