T. J. Parker
A5054325196- Planetary Science and Exploration
- Astro and Planetary Science
- Space Exploration and Technology
- Geology and Paleoclimatology Research
- Space Science and Extraterrestrial Life
- Marine and environmental studies
- Methane Hydrates and Related Phenomena
- Maritime and Coastal Archaeology
- Seismic Waves and Analysis
- Geological and Geochemical Analysis
- Geological formations and processes
- Seismology and Earthquake Studies
- Paleontology and Stratigraphy of Fossils
- Aeolian processes and effects
- Geochemistry and Geologic Mapping
- Geophysics and Sensor Technology
- Geological Modeling and Analysis
- Geophysical and Geoelectrical Methods
- Scientific Research and Discoveries
- Spaceflight effects on biology
- Seismic Imaging and Inversion Techniques
- Offshore Engineering and Technologies
- Reservoir Engineering and Simulation Methods
- Hydrocarbon exploration and reservoir analysis
- Drilling and Well Engineering
Jet Propulsion Laboratory
2013-2025
Halliburton (United Kingdom)
2009-2019
California Institute of Technology
2000-2015
New Mexico Institute of Mining and Technology
2015
Incorporated Research Institutions For Seismology
2014
Lockheed Martin (United States)
2005
Arizona State University
1997-2004
Cornell University
1997-2004
Space Science Institute
2004
Ames Research Center
2004
The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of environment that would have been suited support a martian biosphere founded on chemolithoautotrophy. This aqueous was characterized by neutral pH, low salinity, variable redox states both iron sulfur species. Carbon, hydrogen, oxygen, sulfur, nitrogen, phosphorus were measured directly as key biogenic elements; inference, is assumed available. probably had...
Spirit landed on the floor of Gusev Crater and conducted initial operations soil‐covered, rock‐strewn cratered plains underlain by olivine‐bearing basalts. Plains surface rocks are covered wind‐blown dust show evidence for enrichment soluble species as vein void‐filling materials coatings. The is result a minor amount transport deposition aqueous processes. Layered granular deposits were discovered in Columbia Hills, with outcrops that tend to dip conformably topography. interpreted be...
Ancient lake system at Gale crater Since 2012, the Curiosity rover has been diligently studying rocky outcrops on Mars, looking for clues about past water, climate, and habitability. Grotzinger et al. describe analysis of a huge section sedimentary rocks near crater, where Mount Sharp now stands (see Perspective by Chan). The features within these sediments are reminiscent delta, stream, deposits Earth. Although individual lakes were probably transient, it is likely that there was enough...
The Mars Exploration Rover Opportunity has investigated the landing site in Eagle crater and nearby plains within Meridiani Planum. soils consist of fine-grained basaltic sand a surface lag hematite-rich spherules, spherule fragments, other granules. Wind ripples are common. Underlying thin soil layer, exposed small impact craters troughs, flat-lying sedimentary rocks. These rocks finely laminated, rich sulfur, contain abundant sulfate salts. Small-scale cross-lamination some locations...
The northern lowland plains comprise approximately one third Mars' surface area. Most outflow channels and many valley networks debouch into the lowlands, yet there is little or no morphologic evidence to suggest that channel cutting continued far plains, despite a basinward regional topographic gradient. immediate fate of water discharged from these was dependent on prevailing paleoclimate at time its emplacement. Though current models martian mean annual temperatures were likely below...
The Mars Exploration Rover Spirit and its Athena science payload have been used to investigate a landing site in Gusev crater. is hypothesized be the of former lake, but no clear evidence for lacustrine sedimentation has found date. Instead, dominant lithology basalt, geologic processes are impact events eolian transport. Many rocks exhibit coatings other characteristics that may minor aqueous alteration. Any sediments exist at this location within apparently buried by lavas undergone...
The Microscopic Imager (MI) on the Mars Exploration Rover Opportunity has returned images of with higher resolution than any previous camera system, allowing detailed petrographic and sedimentological studies rocks soils at Meridiani Planum landing site. Designed to simulate a geologist's hand lens, MI is mounted Opportunity's instrument arm can resolve objects 0.1 mm across or larger. This paper provides an overview operations, data calibration, analysis during first 900 sols (Mars days)...
We determined radiogenic and cosmogenic noble gases in a mudstone on the floor of Gale Crater. A K-Ar age 4.21 ± 0.35 billion years represents mixture detrital authigenic components confirms expected antiquity rocks comprising crater rim. Cosmic-ray-produced (3)He, (21)Ne, (36)Ar yield concordant surface exposure ages 78 30 million years. Surface occurred mainly present geomorphic setting rather than during primary erosion transport. Our observations are consistent with deposition shortly...
The Mars Science Laboratory (MSL) Hand Lens Imager (MAHLI) investigation will use a 2-megapixel color camera with focusable macro lens aboard the rover, Curiosity, to investigate stratigraphy and grain-scale texture, structure, mineralogy, morphology of geologic materials in northwestern Gale crater. Of particular interest is stratigraphic record ∼5 km thick layered rock sequence exposed on slopes Aeolis Mons (also known as Mount Sharp). instrument consists three parts, head mounted turret...
Chemical analyses returned by Mars Pathfinder indicate that some rocks may be high in silica, implying differentiated parent materials. Rounded pebbles and cobbles a possible conglomerate suggest fluvial processes imply liquid water equilibrium with the atmosphere thus warmer wetter past. The moment of inertia indicates central metallic core 1300 to 2000 kilometers radius. Composite airborne dust particles appear magnetized freeze-dried maghemite stain or cement have been leached from...
Images of the martian surface returned by Imager for Mars Pathfinder (IMP) show a complex ridges and troughs covered rocks that have been transported modified fluvial, aeolian, impact processes. Analysis spectral signatures in scene (at 440- to 1000-nanometer wavelength) reveal three types rock four classes soil. Upward-looking IMP images predawn sky thin, bluish clouds probably represent water ice forming on local atmospheric haze (opacity approximately 0.5). Haze particles are about 1...
Rocks at the Mars Pathfinder site are probably locally derived. Textures on rock surfaces may indicate volcanic, sedimentary, or impact‐generated rocks, but aeolian abration and dust coatings prevent unambiguous interpretation. Multispectral imaging has resolved four spectral classes of rocks: gray red, which occur different same rocks; pink, is soil crusts; maroon, occurs as large boulders, mostly in far field. assigned to two trends based position peak reflectance: primary trend contains...
The selection of Meridiani Planum and Gusev crater as the Mars Exploration Rover landing sites took over 2 years, involved broad participation science community via four open workshops, narrowed an initial ∼155 potential (80–300 × 30 km) to finalists based on safety. Engineering constraints important included (1) latitude (10°N–15°S) for maximum solar power, (2) elevation (less than −1.3 sufficient atmosphere slow lander, (3) low horizontal winds, shear, turbulence in last few kilometers...
The Mars Exploration Rover Opportunity touched down at Meridiani Planum in January 2004 and since then has been conducting observations with the Athena science payload. rover traversed more than 5 km, carrying out first outcrop‐scale investigation of sedimentary rocks on Mars. are sandstones formed by eolian aqueous reworking sand grains that composed mixed fine‐grained siliciclastics sulfates. siliciclastic fraction was produced chemical alteration a precursor basalt. sulfates dominantly...
A preliminary survey of Magellan imagery reveals more than 200 newly discovered relic channel and valley landform complexes. For purposes discussion the channels can be classed as simple, complex, compound. Integrated valleys also occur. Simple include (1) sinuous rules that closely resemble their lunar counterparts (2) a recognized long form high width‐to‐depth ratio remarkably constant width. Herein designated canali, most spectacular these is 6800 km long. One compound channels, an...
Abstract The Mars Science Laboratory Mast camera and Descent Imager investigations were designed, built, operated by Malin Space Systems of San Diego, CA. They share common electronics focal plane designs but have different optics. There are two Mastcams dissimilar length. Mastcam‐34 has an f /8, 34 mm length lens, the M‐100 /10, 100 lens. M‐34 field view is about 20° × 15° with instantaneous (IFOV) 218 μrad; (FOV) 6.8° 5.1° IFOV 74 μrad. can focus from 0.5 m to infinity, ~1.6 infinity. All...
[1] Opportunity has been traversing the Meridiani plains since 25 January 2004 (sol 1), acquiring numerous observations of atmosphere, soils, and rocks. This paper provides an overview key discoveries between sols 511 2300, complementing earlier papers covering results from initial phases mission. Key new include (1) atmospheric argon measurements that demonstrate importance transport to winter carbon dioxide polar ice caps; (2) showing aeolian ripples were generated by easterly winds during...
Abstract A morphometric and morphologic catalog of ~100 small craters imaged by the Opportunity rover over 33.5 km traverse between Eagle Endeavour on Meridiani Planum shows in six stages degradation that range from fresh blocky to eroded shallow depressions ringed planed off rim blocks. The age each class <50–200 ka ~20 Ma has been determined size‐frequency distribution catalog, retention Planum, latest phase ripple migration. rate crater depth, height, ejecta removal age. These rates...
Discovery of dust devil vortices in Mars Pathfinder (MPF) images reveals a entrainment mechanism at work on Mars. Scattering visible light by the Martian atmosphere creates pronounced haze, preventing conventional image processing from displaying plumes. Spectral differencing techniques have enhanced five localized plumes general haze acquired near midday, which we determine to be devils. Processing 440 nm highlights devils as distinct occultation features against horizon. The are...
Panoramic Camera images at Gusev crater reveal a rock-strewn surface interspersed with high- to moderate-albedo fine-grained deposits occurring in part as drifts or small circular swales hollows. Optically thick coatings of ferric iron-rich dust dominate most bright soil and rock surfaces. Spectra some darker surfaces regions exposed by brushing grinding show near-infrared spectral signatures consistent the presence mafic silicates such pyroxene olivine. Atmospheric observations steady...
Mars Pathfinder successfully landed at Ares Vallis on July 4, 1997, deployed and navigated a small rover about 100 m clockwise around the lander, collected data from three science instruments ten technology experiments. The mission operated for months returned 2.3 Gbits of data, including over 16,500 lander 550 images, 16 chemical analyses rocks soil, 8.5 million individual temperature, pressure wind measurements. Path‐finder is best known location Mars, having been clearly identified with...