A new planetary mapping for future space missions

The wide studies of Solar system, including different planetary bodies, were announced by new Russian space program. Their geodesy and cartography support provides by MIIGAiK Extraterrestrial Laboratory (http://mexlab.miigaik.ru/eng) in frames of the new project ''Studies of Fundamental Geodetic Parameters and Topography of Planets and Satellites''. The objects of study are satellites of the outer planets (satellites of Jupiter - Europa, Calisto and Ganymede; Saturnine satellite Enceladus), some planets (Mercury and Mars) and the satellites of the terrestrial planets - Phobos (Mars) and the Moon (Earth). The new research project, which started in 2014, will address the following important scientific and practical tasks: - Creating new three-dimensional geodetic control point networks of satellites of the outer planets using innovative photogrammetry techniques; - Determination of fundamental geodetic parameters and study size, shape, and spin parameters and to create the basic framework for research of their surfaces; - Studies of relief of planetary bodies and comparative analysis of general surface characteristics of the Moon, Mars, and Mercury, as well as studies of morphometric parameters of volcanic formations on the Moon and Mars; - Modeling of meteoritic bombardment of celestial bodies and the study of the dynamics of particle emissions caused by a meteorite impacts; - Development of geodatabase for studies of planetary bodies, including creation of object catalogues, (craters and volcanic forms, etc.), and thematic mapping using GIS technology. The significance of the project is defined both by necessity of obtaining fundamental characteristics of the Solar System bodies, and practical tasks in preparation for future Russian and international space missions to the Jupiter system (Laplace-P and JUICE), the Moon (Luna-Glob and Luna-Resource), Mars (Exo-Mars), Mercury (Bepi-Colombo), and possible mission to Phobos (project Boomerang). For cartographic support of future missions, we have created various maps as results of first year research: new base maps of Ganymede, including a hypsometric map and a global surface map; the base and thematic maps of Phobos which were updated using new image data sets from Mars Express; a newest map of topographic roughness of Mercury (for north polar area) 2 and a map of topographic roughness of the Moon using laser altimeter data processing obtained by MESSENGER (MLA) and LRO (LOLA) for their comparative analyses; a new global hypsometric map of the Moon. Published version of the maps will be presented at the conference, and all data products using for mapping will be available via MExLab Geoportal (http://cartsrv.mexlab.ru/geoportal/\#body/). Acknowledgments. This work was carried out in MIIGAiK and supported by Russian Science Foundation, project \#14-22-00197

Summary of the Mars recent climate change workshop NASA/Ames Research Center, May 15-17, 2012

International audienceThis note summarizes the results from the Mars recent climate change workshop at NASA/Ames Research Center, May 15-17, 2012

Geologic interpretation of the NIR images taken by the Venus Monitorin Camera

Joint analysis of the VMC 1 micron surface radiation images for the Beta-Phoebe region, the results of Magellan radar survey and the model images of this region showed that the VMC images provided reliable information on spatial variations of the NIR radiation of the Venus surface, which can be interpreted in terms of geological characteristics of the studied area,including potential compositional differences between geologic units. In particular, our analysis showed that surface of several relatively small massifs of tessera terrain observed in the study area showed the 1 micron emissivity which is not noticeably different from that typical of surrounding basaltic plains. This may mean that these tesserae are composed of basalts or it can be a result of pollution of surface of tessera by the wind-blown fine debris brought from the surrounding plains. This controversy hopefully may be resolved in future studies if much larger tessera massifs will be imaged by VMC. Analysis of the VMC images of the mountain tops covered with the enigmatic radar-low-emissivity material suggests that its 1 micron emissivity do not significantly differ from the emissivity of basalts that is consistent with earlier published geochemical conlusions that it can be hematite, or magnetite, or pyrite. We have found that the radar-bright and radar-dark subunits of the basaltic regional plains dominating in the study area do not show noticeable difference in their 1 micron emissivity. This was interpreted as indication on rather similar composition of these two plains varieties and differences in their radar brightness are probably due to differences in their surface roughness. We did not find any indication on ongoing volcanic eruptions in the study area that probably may be due to low spatial resolution of the VMC imaging and/or to actual absence of the ongoing volcanic activity. In our future studies we plan to involve to the analysis the new data acquired in the continuing Venus Express mission and to apply techniques of quantitative analysis to the existing and future data

Geologic Analysis of the Surface Thermal Emission Images taken by the VMC Camera, Venus Express

Introduction. The Venus Monitoring Camera (VMC) onboard Venus Express takes images in 4 channels, one of which is centered at 1.01 μm. When the camera looks at the night side of Venus, this channel registers thermal emission from the planet surface from mid-southern to mid-northern latitudes [1]. Due to scattering of the emitted radiation in the atmosphere and the cloud layer, the effective spatial resolution in the surface images is ~50 km. Thus, modeling the atmospheric blurring is essential for this work. Here we report results of preliminary analysis of some VMC 1-μm images. Intensity of the surface thermal emission at 1 μm depends strongly on its temperature and thus on surface elevation as well as on surface emissivity and cloud opacity. But emissivity of the surface material depends also on surface texture and mineralogy so the image analysis can provide an information on these parameters. Also, if there is an ongoing volcanic eruption in the camera field of view, it might be noticed on the images

Geologic interpretation of the near-infrared images of the surface taken by the Venus Monitoring Camera, Venus Express

We analyze night-time near-infrared (NIR) thermal emission images of the Venus surface obtained with the 1-μm channel of the Venus Monitoring Camera onboard Venus Express. Comparison with the results of the Magellan radar survey and the model NIR images of the Beta-Phoebe region show that the night-time VMC images provide reliable information on spatial variations of the NIR surface emission. In this paper we consider if tessera terrain has the different NIR emissivity (and thus mineralogic composition) in comparison to the surrounding basaltic plains. This is done through the study of an area SW of Beta Regio where there is a massif of tessera terrain, Chimon-mana Tessera, surrounded by supposedly basaltic plains. Our analysis showed that 1-μm emissivity of tessera surface material is by 15–35% lower than that of relatively fresh supposedly basaltic lavas of plains and volcanic edifices. This is consistent with hypothesis that the tessera material is not basaltic, maybe felsic, that is in agreement with the results of analyses of VEX VIRTIS and Galileo NIMS data. If the felsic nature of venusian tesserae will be confirmed in further studies this may have important implications on geochemical environments in early history of Venus. We have found that the surface materials of plains in the study area are very variegated in their 1-μm emissivity, which probably reflects variability of degree of their chemical weathering. We have also found a possible decrease of the calculated emissivity at the top of Tuulikki Mons volcano which, if real, may be due to different (more felsic?) composition of volcanic products on the volcano summit