27 research outputs found
Searching for evidence of hydrothermal activity at Apollinaris Mons, Mars
No full textA multidisciplinary approach involving various remote sensing instruments is used to investigate Apollinaris Mons, a prominent volcano on Mars, as well as the surrounding plains for signs of prolonged hydrologic and volcanic, and possibly hydrothermal activity. The main findings include (1) evidence from laser altimetry indicating the large thickness (1.5–2 km at some locations) of the fan deposits draping the southern flank contrary to previous estimates, coupled with possible layering which point to a significant emplacement phase at Apollinaris Mons, (2) corroboration of Robinson et al. (Robinson, M.S., Mouginis-Mark, P.J., Zimbelman, J.R., Wu, S.S.C., Ablin, K.K., Howington-Kraus, A.E. [1993]. Icarus 104, 301–323) hypothesis regarding the formation of incised valleys on the western flanks by density current erosion which would indicate magma–water interaction or, alternatively, volatile-rich magmas early in the volcano’s history, (3) mounds of diverse geometric shapes, many of which display summit depressions and occur among faults and fractures, possibly marking venting, (4) strong indicators on the flanks of the volcano for lahar events, and possibly, a caldera lake, (5) ubiquitous presence of impact craters displaying fluidized ejecta in both shield-forming (flank and caldera) materials and materials that surround the volcano that are indicative of water-rich target materials at the time of impact, (6) long-term complex association in time among shield-forming materials and Medusae Fossae Formation.\ud
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The findings point to a site of extensive volcanic and hydrologic activity with possibly a period of magma–water interaction and hydrothermal activity. Finally, we propose that the mound structures around Apollinaris should be prime targets for further in situ exploration and search for possible exobiological signatures
Modeling martian thermal inertia in a distributed memory high performance computing environment
No full textComposition and thermal inertia of the Mawrth Vallis region of Mars from TES and THEMIS data
No full textClay mineral-bearing deposits previously discovered on Mars with near infrared (λ = 0.3 - 5 μm) remote sensing data are of major significance for understanding the aqueous history, geological evolution, and past habitability of Mars. In this study, we analyzed the thermal infrared (λ = 6 - 35 μm) surface properties of the most extensive phyllosilicate deposit on Mars: the Mawrth Vallis area. Clay mineral-bearing units, which in visible images appear to be relatively light-toned, layered bedrock, have thermal inertia values ranging from 150 to 460 J m-2 K-1 s-1/2. This suggests the deposits are composed of a mixture of rock with sand and dust at 100-meter scales. Dark-toned materials that mantle the clay-bearing surfaces have thermal inertia values ranging from 150 to 800, indicating variable degrees of rockiness or induration of this younger sedimentary or pyroclastic unit. Thermal Emission Spectrometer (TES) spectra of the light-toned rocks were analyzed with a number of techniques, but none of the results shows a large phyllosilicate component as has been detected in the same surfaces with near-infrared data. Instead, TES spectra of light-toned surfaces are best modeled by a combination of plagioclase feldspar, high-silica materials (similar to impure opaline silica or felsic glass), and zeolites. We propose three hypotheses for why the clay minerals are not apparent in thermal infrared data, including effects due to surface roughness, sub-pixel mixing of multiple surface temperatures, and low absolute mineral abundances combined with differences in spatial sampling between instruments. Zeolites modeled in TES spectra could be a previously unrecognized component of the alteration assemblage in the phyllosilicate-bearing rocks of the Mawrth Vallis area. TES spectral index mapping suggests that (Fe/Mg)-clays detected with near infrared data correspond to trioctahedral (Fe2+) clay minerals rather than nontronite-like clays. The average mineralogy and geologic context of these complex, interbedded deposits suggests they are either aqueous sedimentary rocks, altered pyroclastic deposits, or a combination of both. © 2008 Elsevier Inc.link_to_subscribed_fulltex
Regional-scale stratigraphy of surface units in Tyrrhena and Iapygia Terrae, Mars: Insights into highland crustal evolution and alteration history
No full text30-m HRSC DTM Mosaic of Gale Crater, Mars
No full textDigital terrain model (DTM) mosaic of Gale crater, Mars, processed from High-Resolution Stereo Camera (HRSC) stereo images using the modification of DLR-VICAR described by Kim and Muller (2009).
Format: GeoTiff
Projection: Equidistant cylindrical
Datum: Spheroid (r = 3396.190 km)
Bit depth: Float32
Grid-spacing: 30 m/pixel
Terrain reference: 200-m MOLA and HRSC blended global DTM (Fergason et al. 2018)
HRSC source images: H1938_0000, H1927_0000, and H1916_0000The first author is now at Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California. Contact: [email protected]
Thermophysical Properties of Martian Fluvial Sinuous Ridges: Inferences on “Inverted Channel” Induration Agent
No full textWHAT CAN BE DEDUCED ABOUT THE CAPPING UNIT OF MARTIAN ‘INVERTED CHANNELS’ FROM THEIR THERMOPHYSICAL PROPERTIES?
No full textEffects of Activity, Alcohol, Smoking, and the Menstrual Cycle on Liquid Crystal Breast Thermography
No full textAuthor Institution: Department of Biological Sciences, Kent State UniversityThis study is part of a continuing program to evaluate the efficacy and reliability of liquid-crystal thermography in breast-cancer detection. The purpose was to evaluate any possible effect(s) of daily activity, smoking, alcohol consumption, amount of sleep, and the menstrual cycle on the liquid-crystal thermographic breast-pattern. Ten apparently healthy women served as subjects and were examined by liquid-crystal thermography every day for 28 (minimum) to 45 (maximum) consecutive days for thermogram changes. The results indicate that daily activity and the menstrual cycle should not affect the reliability of liquid-crystal thermogram interpretation in breast-cancer studies. Alcohol consumption and cigarette smoking prior to liquid-crystal thermographic examination could change the normal pattern to an extent that reliable interpretation might not be possible. There appears to be a thermographic-pattern change closely associated with the probable time of ovulation
Towards a Planetary Spatial Data Infrastructure
No full textPlanetary science is the study of planets, moons, irregular bodies such as asteroids and the processes that create and modify them. Like terrestrial sciences, planetary science research is heavily dependent on collecting, processing and archiving large quantities of spatial data to support a range of activities. To address the complexity of storing, discovering, accessing, and utilizing spatial data, the terrestrial research community has developed conceptual Spatial Data Infrastructure (SDI) models and cyberinfrastructures. The needs that these systems seek to address for terrestrial spatial data users are similar to the needs of the planetary science community: spatial data should just work for the non-spatial expert. Here we discuss a path towards a Planetary Spatial Data Infrastructure (PSDI) solution that fulfills this primary need. We first explore the linkage between SDI models and cyberinfrastructures, then describe the gaps in current PSDI concepts, and discuss the overlap between terrestrial SDIs and a new, conceptual PSDI that best serves the needs of the planetary science community.</jats:p
