A5078649983- Planetary Science and Exploration
- Astro and Planetary Science
- Space Exploration and Technology
- Geology and Paleoclimatology Research
- Space Science and Extraterrestrial Life
- Methane Hydrates and Related Phenomena
- Aeolian processes and effects
- Spacecraft and Cryogenic Technologies
- Scientific Research and Discoveries
- Cryospheric studies and observations
- Spaceflight effects on biology
- Isotope Analysis in Ecology
- Atmospheric and Environmental Gas Dynamics
- Landslides and related hazards
- Spacecraft Design and Technology
- Arctic and Antarctic ice dynamics
- Geotechnical and Geomechanical Engineering
- Marine and environmental studies
- Space exploration and regulation
- Rock Mechanics and Modeling
- Geological and Geochemical Analysis
- earthquake and tectonic studies
- Hydrocarbon exploration and reservoir analysis
- Geological Studies and Exploration
- Calibration and Measurement Techniques
University of Arizona
2015-2024
University of Massachusetts Lowell
2024
Planetary Science Institute
2012-2023
Lunar and Planetary Institute
2012-2023
Central Bank of Ireland
2023
Trinity College Dublin
2023
University of Padua
2017
United States Geological Survey
2007-2016
Astrogeology Science Center
2007-2016
Georgia Institute of Technology
2014
Rare meter-scale slope features on Mars might be explained by transient flows of liquid salty water.
Martian Impact craters form frequently on Mars, exposing material that would otherwise remain hidden below the surface. Byrne et al. (p. 1674 ) identified mid-latitude formed over last few years, imaged them in great detail with a camera board Mars Reconnaissance Orbiter, and monitored subsequent changes. The excavated buried water ice, which was later seen sublimating away. In addition, some might have completely through ice. observations are consistent models other suggest ice should be...
Shallow Radar soundings from the Mars Reconnaissance Orbiter reveal a buried deposit of carbon dioxide (CO(2)) ice within south polar layered deposits with volume 9500 to 12,500 cubic kilometers, about 30 times that previously estimated for pole residual cap. The occurs stratigraphic unit is uniquely marked by collapse features and other evidence interior CO(2) volatile release. If released into atmosphere at high obliquity, reservoir would increase atmospheric mass up 80%, leading more...
Water ice cliffs on Mars Some locations are known to have water just below the surface, but how much has remained unclear. Dundas et al. used data from two orbiting spacecraft examine eight where erosion occurred. This revealed composed mostly of ice, which is slowly sublimating as it exposed atmosphere. The sheets extend surface a depth 100 meters or more and appear contain distinct layers, could preserve record Mars' past climate. They might even be useful source for future human...
INTRODUCTION Classic volcanism prevalent on terrestrial planets and volatile-poor protoplanets, such as asteroid Vesta, is based silicate chemistry often expressed by volcanic edifices (unless erased impact bombardment). In ice-rich bodies with sufficiently warm interiors, cryovolcanism involving liquid brines can occur. Smooth plains some icy satellites of the outer solar system have been suggested possibly cryovolcanic in origin. However, evidence for has proven elusive. Ceres a...
Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation grainfall (sand avalanching down dune slipface) operate on both worlds. Here, we show are subject to an additional modification process not found Earth: springtime sublimation Mars' CO(2) seasonal polar caps. Numerous in north region have experienced morphological changes within Mars year, detected images acquired by High-Resolution...
Water has supposedly marked the surface of Mars and produced characteristic landforms. To understand history water on Mars, we take a close look at key locations with High-Resolution Imaging Science Experiment board Reconnaissance Orbiter, reaching fine spatial scales 25 to 32 centimeters per pixel. Boulders ranging up approximately 2 meters in diameter are ubiquitous middle high latitudes, which include deposits previously interpreted as finegrained ocean sediments or dusty snow. Bright...
The tantalizing prospect of a readable record martian climatic variations has driven decades work toward deciphering the stratigraphy polar layered deposits and understanding role residual ice caps that cover them. Spacecraft over past decade have provided massive infusion new data into Mars science. Polar science benefited immensely due to near-polar orbits most orbiting missions successful landing Phoenix spacecraft in northern high latitudes. Topographic, thermal, radar, hyperspectral,...
The surface of dwarf planet Ceres contains hydroxyl-rich materials. Theories predict a water ice-rich mantle, and vapor emissions have been observed, yet no (H2O) has previously identified. Visible InfraRed (VIR) mapping spectrometer onboard the Dawn spacecraft now detected absorption features within low-illumination, highly reflective zone in Oxo, 10-kilometer, geologically fresh crater, on five occasions over period 1 month. Candidate materials are H2O ice mineral hydrates. Exposed would...
The Colour and Stereo Surface Imaging System (CaSSIS) is the main imaging system onboard European Space Agency's ExoMars Trace Gas Orbiter (TGO) which was launched on 14 March 2016. CaSSIS intended to acquire moderately high resolution (4.6 m/pixel) targeted images of Mars at a rate 10–20 per day from roughly circular orbit 400 km above surface. Each image can be acquired in up four colours stereo capability foreseen by use novel rotation mechanism. A typical product one acquisition will...
Analysis of Dawn spacecraft Framing Camera image data allows evaluation the topography and geomorphology features on surface Ceres. The dwarf planet is dominated by numerous craters, but other are also common. Linear structures include both those associated with impact craters that do not appear to have any correlation an event. Abundant lobate flows identified, domical found at a range scales. Features suggestive near-surface ice, cryomagmatism, cryovolcanism been identified. Although...
Abstract Twenty small new impact craters or clusters have been observed to excavate bright material inferred be ice at mid‐latitudes and high latitudes on Mars. In the northern hemisphere, are widely distributed geographically occur as low 39°N. Stability modeling suggests that this distribution requires a long‐term average atmospheric water vapor content around 25 precipitable micrometers, more than double present value, which is consistent with expected effect of recent orbital variations....
Abstract Thermomechanical processes such as fatigue and shock have been suggested to cause contribute rock breakdown on Earth, other planetary bodies, particularly airless bodies in the inner solar system. In this study, we modeled grain‐scale stresses induced by diurnal temperature variations simple microstructures made of pyroxene plagioclase various system bodies. We found that a heterogeneous microstructure Moon experiences peak tensile order 100 MPa. The are controlled coefficient...
Abstract Although ice in the Martian midlatitudes is typically covered by a layer of dust or regolith, it exposed some locations fresh impact craters erosional scarps. In both cases, massive excess with low lithic content. We find that scarps occur between 50° and 61° north south latitude they are concentrated near Milankovič crater northern hemisphere southeast Hellas basin southern hemisphere. These may represent particularly thick clean bodies ice. Pits created retreat...
In their pioneering work, Leighton and Murray argued that the Mars atmosphere, which at present is 95% carbon dioxide, controlled by vapor equilibrium with a much larger polar reservoir of solid dioxide. Here we argue small cannot function as long-term buffer to more massive atmosphere. Our work based on modeling circular depressions commonly found south cap. We dioxide ice layer about 8 meters thick being etched away reveal water underneath. This consistent thermal infrared data from...
In this paper we define and describe morphological features that have colloquially been termed “spiders” map their distribution in the south polar region of Mars. We show these go through a distinct seasonal evolution, exhibiting dark plumes associated fan‐shaped deposits during local defrosting cap. documented evolution cryptic found spiders only occur within terrain. These observations are consistent with geyser‐like model for spider formation. Association transparent (cryptic) portion cap...
Fresh‐appearing gully deposits are found at tens of sites in the southern hemisphere Mars. These have latitudinal and azimuthal dependences similar to overall preferences southern‐hemisphere gullies, suggesting that most gullies can undergo such events. Definite changes seen ten sites, including two previously reported. include visible modification channels aprons. Those formation intervals constrained better than one Mars year tend winter exclude summer, seasonal activity. This activity is...