A5014840262- Planetary Science and Exploration
- Astro and Planetary Science
- Space Exploration and Technology
- Geology and Paleoclimatology Research
- Space Science and Extraterrestrial Life
- Scientific Research and Discoveries
- Methane Hydrates and Related Phenomena
- Climate change and permafrost
- Spacecraft and Cryogenic Technologies
- Spaceflight effects on biology
- Cryospheric studies and observations
- Polar Research and Ecology
- Aeolian processes and effects
- Hydrocarbon exploration and reservoir analysis
- Isotope Analysis in Ecology
- Landslides and related hazards
- Geochemistry and Geologic Mapping
- Geotechnical and Geomechanical Engineering
- Arctic and Antarctic ice dynamics
- Space exploration and regulation
- Electron and X-Ray Spectroscopy Techniques
- Integrated Circuits and Semiconductor Failure Analysis
- Marine and environmental studies
- Atmospheric and Environmental Gas Dynamics
- Rocket and propulsion systems research
Cornell University
2019-2025
Planetary Science Institute
2019-2023
Johns Hopkins University Applied Physics Laboratory
2017-2019
Kentucky State University
2018
Southwest Research Institute
2006-2016
Johns Hopkins University
2015
Laboratory for Atmospheric and Space Physics
2003-2012
University of Colorado Boulder
2001-2011
Max Planck Society
2010
Jet Propulsion Laboratory
2007-2009
The HiRISE camera features a 0.5 m diameter primary mirror, 12 effective focal length, and plane system that can acquire images containing up to 28 Gb (gigabits) of data in as little 6 seconds. will provide detailed (0.25 1.3 m/pixel) covering ∼1% the Martian surface during 2‐year Primary Science Phase (PSP) beginning November 2006. Most include color 20% potential field view. A top priority is ∼1000 stereo pairs apply precision geometric corrections enable topographic measurements better...
The Thermal Emission Spectrometer (TES) investigation on Mars Global Surveyor (MGS) is aimed at determining (1) the composition of surface minerals, rocks, and ices; (2) temperature dynamics atmosphere; (3) properties atmospheric aerosols clouds; (4) nature polar regions; (5) thermophysical materials. These objectives are met using an infrared (5.8‐ to 50‐μm) interferometric spectrometer, along with broadband thermal (5.1‐ 150‐μm) visible/near‐IR (0.3‐ 2.9‐μm) radiometers. MGS TES instrument...
Phoenix Ascending The mission landed on Mars in March 2008 with the goal of studying ice-rich soil planet's northern arctic region. included a robotic arm, camera attached to it, capacity excavate through ice layer beneath scoop up and water samples, deliver them combination other instruments—including wet chemistry lab high-temperature oven combined mass spectrometer—for chemical geological analysis. Using this setup, Smith et al. (p. 58 ) found at depths 5 15 centimeters, Boynton 61...
Neutron data observed using the Spectrometer aboard 2001 Mars Odyssey provide a lower limit to global inventory of Martian water‐equivalent hydrogen. Hydrogen‐rich deposits ranging between about 20% and 100% by mass are found poleward ±50° latitude, less rich, but significant, at near‐equatorial latitudes. The equatorial ±45° latitude range 2% 10% hydrogen reach their maximum in two regions that straddle 0‐km elevation contour. Higher water abundances, up ∼11%, required subsurface regolith...
Mars undergoes significant oscillations in its orbit, which will have a pronounced effect on climate and, particular, the behavior of subsurface water ice. We explore and map ice Martian near‐surface regolith over past 1 m.y. using diffusion condensation model presented an earlier paper, with two primary modifications to include orbitally induced variations insolation atmospheric abundance. find that ground differs significantly from at present epoch, primarily result high‐amplitude...
A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated description Special Regions on as places where terrestrial organisms might replicate (per COSPAR Planetary Protection Policy). This review update was conducted by an international team (SR-SAG2) drawn from both biological science exploration communities, focused understanding when could occur. The study applied recently available data about martian environments organisms, building a previous analysis...
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...
The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter has imaged internal stratigraphy of north polar layered deposits Mars. reflections within reveal a laterally continuous deposition layers, which typically consist four packets finely spaced reflectors separated by homogeneous interpacket regions nearly pure ice. packet/interpacket structure can be explained approximately million-year periodicities in Mars' obliquity or orbital eccentricity. observed 100-meter maximum deflection...
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...
To investigate the stability of ground ice within top several meters Martian regolith, time‐dependent models thermal and diffusive behavior regolith have been developed. The geographic distribution inertia albedo as well latitudinal variation in insolation included calculations surface subsurface temperatures between ±60° latitude. Ground was found to be stable where annual mean were below atmospheric frost point. This generally occurs poleward mid‐latitudes. latitude which is varies by...
Geologic features resembling terrestrial water‐carved gullies imply that liquid water has flowed recently on the surface of Mars and challenge our views present‐day low‐temperature environment. We evaluate two possible mechanisms for formation under environmental conditions we expect to have existed in its recent past. First, examine stability ground ice permafrost potential melting near‐surface (in top few meters soil) by solar heating subsurface conduction. Second, refreezing at shallow...
A primary objective of the Phoenix mission was to examine characteristics high latitude ground ice on Mars. We report observations ice, its depth distribution and stability characteristics, origins history. High explored through a dozen trench complexes landing thruster pits, over range polygon morphological provinces. Shallow found be abundant under layer relatively loose ice‐free soil with mean 4.6 cm, which varied by more than 10x from trench. These variations can attributed mainly slope...
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...
A time‐dependent viscoelastic model of thermal stress in Martian ice‐rich permafrost is developed to test the hypothesis that small‐scale polygonal features observed from orbit and by Viking Lander 2 are result contraction cracking, as commonly occurs terrestrial permafrost. Results indicate significant tensile a seasonal cycles ground temperature. Using conservative rheological parameters appropriate for ice at low temperatures, stresses poleward about 20° 30° latitude easily exceed...
Geomorphic evidence suggests that recent gullies on Mars were formed by fluvial activity. The Martian gully features are significant because their existence implies the presence of liquid water near surface in geologically times. Irrespective ultimate source fluid carving gullies, we seek to understand behavior this after it reaches surface. We find contrary popular belief, fluvially carved consistent with formation conditions such as now occur Mars, outside temperature‐pressure stability...
The thermal and electrical conductivity probe (TECP), a component of the Microscopy, Electrochemistry, Conductivity Analyzer (MECA), was included on Phoenix Lander to conduct in situ measurements exchange heat water Martian polar terrain. TECP measured regolith conductivity, capacity, temperature, dielectric permittivity throughout mission. A relative humidity sensor returned first from surface. dry overburden above ground ice is good insulator (average κ = 0.085 W m −1 K average Cρ 1.05 ×...
Research Article| January 01, 2012 Planet-wide sand motion on Mars Nathan T. Bridges; Bridges 1Johns Hopkins University Applied Physics Laboratory, 11100 Johns Road, Laurel, Maryland 20723, USA Search for other works by this author on: GSW Google Scholar Mary C. Bourke; Bourke 2Planetary Science Institute, Tucson, Arizona 85719, Paul E. Geissler; Geissler 3U.S. Geological Survey, Flagstaff, 86001, Maria Banks; Banks 4Center Earth and Planetary Studies, Smithsonian Air Space Museum,...
We examine potentially periglacial landforms in Mars Orbiter Camera (MOC) and High Resolution Imaging Science Experiment (HiRISE) images at the Phoenix landing site compare them with numerical models of permafrost processes to better understand origin, nature, history surface northern plains Mars. Small‐scale (3–6 m) polygonal‐patterned ground is ubiquitous throughout plains. Larger‐scale (20–25 polygonal patterns regularly spaced (20–35 rubble piles (localized collections rocks boulders)...
The prospect of a future soft landing on the surface Europa is enticing, as it would create science opportunities that could not be achieved through flyby or orbital remote sensing, with direct relevance to Europa's potential habitability. Here, we summarize lander concept, developed by our NASA-commissioned Science Definition Team. concept concentrates observations can best in situ examination from its surface. We discuss suggested objectives and investigations for mission, along model...