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Sample records for arabia terra mars

  1. Ancient Hydrothermal Springs in Arabia Terra, Mars

    NASA Technical Reports Server (NTRS)

    Oehler, Dorothy Z.; Allen, Carlton C.

    2008-01-01

    Hydrothermal springs are important astrobiological sites for several reasons: 1) On Earth, molecular phylogeny suggests that many of the most primitive organisms are hyperthermophiles, implying that life on this planet may have arisen in hydrothermal settings; 2) on Mars, similar settings would have supplied energy- and nutrient-rich waters in which early martian life may have evolved; 3) such regions on Mars would have constituted oases of continued habitability providing warm, liquid water to primitive life forms as the planet became colder and drier; and 4) mineralization associated with hydrothermal settings could have preserved biosignatures from those martian life forms. Accordingly, if life ever developed on Mars, then hydrothermal spring deposits would be excellent localities in which to search for morphological or chemical remnants of that life. Previous attempts to identify martian spring deposits from orbit have been general or limited by resolution of available data. However, new satellite imagery from HiRISE has a resolution of 28 cm/pixel which allows detailed analysis of geologic structure and geomorphology. Based on these new data, we report several features in Vernal Crater, Arabia Terra that we interpret as ancient hydrothermal springs.

  2. Supervolcanoes within an ancient volcanic province in Arabia Terra, Mars.

    PubMed

    Michalski, Joseph R; Bleacher, Jacob E

    2013-10-01

    Several irregularly shaped craters located within Arabia Terra, Mars, represent a new type of highland volcanic construct and together constitute a previously unrecognized Martian igneous province. Similar to terrestrial supervolcanoes, these low-relief paterae possess a range of geomorphic features related to structural collapse, effusive volcanism and explosive eruptions. Extruded lavas contributed to the formation of enigmatic highland ridged plains in Arabia Terra. Outgassed sulphur and erupted fine-grained pyroclastics from these calderas probably fed the formation of altered, layered sedimentary rocks and fretted terrain found throughout the equatorial region. The discovery of a new type of volcanic construct in the Arabia volcanic province fundamentally changes the picture of ancient volcanism and climate evolution on Mars. Other eroded topographic basins in the ancient Martian highlands that have been dismissed as degraded impact craters should be reconsidered as possible volcanic constructs formed in an early phase of widespread, disseminated magmatism on Mars. PMID:24091975

  3. Supervolcanoes Within an Ancient Volcanic Province in Arabia Terra, Mars

    NASA Technical Reports Server (NTRS)

    Michalski, Joseph. R.; Bleacher, Jacob E.

    2014-01-01

    Several irregularly shaped craters located within Arabia Terra, Mars represent a new type of highland volcanic construct and together constitute a previously unrecognized martian igneous province. Similar to terrestrial supervolcanoes, these low-relief paterae display a range of geomorphic features related to structural collapse, effusive volcanism, and explosive eruptions. Extruded lavas contributed to the formation of enigmatic highland ridged plains in Arabia Terra. Outgassed sulfur and erupted fine-grained pyroclastics from these calderas likely fed the formation of altered, layered sedimentary rocks and fretted terrain found throughout the equatorial region. Discovery of a new type of volcanic construct in the Arabia volcanic province fundamentally changes the picture of ancient volcanism and climate evolution on Mars. Other eroded topographic basins in the ancient Martian highlands that have been dismissed as degraded impact craters should be reconsidered as possible volcanic constructs formed in an early phase of widespread, disseminated magmatism on Mars.

  4. Evidence for explosive volcanism in Arabia Terra, Mars

    NASA Astrophysics Data System (ADS)

    Michalski, Joseph; Bleacher, Jacob

    2014-05-01

    Several irregularly shaped craters located within Arabia Terra, Mars, represent a new type of volcanic construct and together constitute a previously unrecognized Martian igneous province. Similar to terrestrial supervolcanoes, these low-relief paterae exhibit a range of geomorphic features related to structural collapse, effusive volcanism and explosive eruptions. They were likely active in the Late Noachian or Early Hesperian and would have affected the climate, atmospheric composition, and regional surface geology at that time. Lavas extruded from these calderas contributed to the formation of enigmatic highland ridged plains in Arabia Terra, but these volcanoes do not exhibit shield-like topographic profiles related to the sustained, localized effusive eruption of basaltic lava. We suggest that the lack of a single edifice, the large volume of collapse within an associated with the calderas, and the association of the calderas with vast deposits friable clastic deposits all indicate that these volcanoes were dominated by explosive activity. Layered, friable deposits found throughout Arabia Terra have enigmatic origins, though these materials have been suggested to represent volcanic ash. Attempts to link the locations of various friable deposits in equatorial regions to known volcanic sources have demonstrated that this hypothesis is plausible, but a link between friable deposits and known volcanic sources in this particular region (Arabia Terra) has yet to emerge. We suggest that some of the layered, friable materials were sourced from calderas in Arabia Terra. Outgassed sulphur and water from these calderas would have contributed to the alteration of layered clastic materials in Arabia Terra, and perhaps throughout the equatorial region.

  5. A case for ancient springs in Arabia Terra, Mars.

    PubMed

    Allen, Carlton C; Oehler, Dorothy Z

    2008-12-01

    Based on new image data from the High Resolution Imaging Science Experiment (HiRISE) on Mars Reconnaissance Orbiter (MRO), a case can be made that several structures in Vernal Crater, Arabia Terra are ancient springs. This interpretation is based on comprehensive geomorphologic analysis coupled with assessment of multiple hypotheses. The structures identified extend across several kilometers and are exceptional in that nothing with their detail and scale has been reported from Mars. The deposits are associated with an extensive fracture system that may have facilitated upward flow of warm fluids. Several additional spring-like features occur in Vernal Crater, and it is possible that these are part of a major province of spring activity. Since springs are environments where life could have evolved on Mars, where that life could have found refuge as the climate became colder and drier, and where signatures of that life may be preserved, Vernal Crater may be a site of major astrobiological importance. PMID:19093802

  6. Prospecting for Methane in Arabia Terra, Mars - First Results

    NASA Technical Reports Server (NTRS)

    Allen, Carlton C.; Oehler, Dotoyhy Z.; Venechuk, Elizabeth M.

    2006-01-01

    Methane has been measured in the Martian atmosphere at concentrations of approx. 10 ppb. Since the photochemical lifetime of this gas is approx. 300 years, it is likely that methane is currently being released from the surface. Possible sources for the methane include 1) hydrothermal activity, 2) serpentinization of basalts and other water-rock interactions, 3) thermal maturation of sedimentary organic matter, and 4) metabolism of living bacteria. Any such discovery would revolutionize our understanding of Mars. Longitudinal variations in methane concentration, as measured by the Planetary Fourier Spectrometer (PFS) on Mars Express, show the highest values over Arabia Terra, Elysium Planum, and Arcadia-Memnonia, suggesting localized areas of methane release. We are using orbital data and methodologies derived from petroleum exploration in an attempt to locate these release points.

  7. Hints at diapirism in Arabia Terra bulged craters (Mars)

    NASA Astrophysics Data System (ADS)

    Pozzobon, R.; Massironi, M.; Rossi, A. P.; Sauro, F.; Carli, C.; Marinangeli, L.; Cremonese, G.

    2015-10-01

    Impact craters within Arabia Terra region,on Mars,display a large central bulge, sometimes showing a well-preserved stratification (light albedo layered deposits). In craters like Crommelin or an unnamed crater (that is numbered 12000088) located a few hundreds kilometers on the East some unusual landforms and structures among the layered deposits were observed. In particular, on Crommelin's bulge and its surroundings we found fold systems with axis parallel to the bulge perimeter. The fold sets are typical compressional structure often associated to diapiric rise on Earth[1]. In addition on top of 12000088 crater's bulge the evidence of sulfate signatures was detected as well as the presence of small bowl-shaped depressions. Several fluid-carved channels that depart radially from the bulge are cut by a ring of normal faults,thus suggesting a collapse of the bulge summit. Thus, on the basis of the previous observations it is possible to hypothesize that diapiric rise could have been responsible for central bulging both on Crommelin and 12000088 craters and likely on other bulged craters on Arabia Terra.

  8. Hints at diapirism in Arabia Terra craters, Mars

    NASA Astrophysics Data System (ADS)

    Pozzobon, Riccardo; Pio Rossi, Angelo; Massironi, Matteo; Mazzarini, Francesco; Pondrelli, Monica; Marinangeli, Lucia; Unnithan, Vikram

    2014-05-01

    Arabia Terra is a region of Mars located at the boundary between the southern highlands and the northern lowlands and classically dominated by heavily cratered terrain. Unlike the rest of the topographic dichotomy on the planet, in Arabia Terra the elevation transition is very gentle, falling of 4 km over a distance of 2500 km (average slope = 0.0016°). Most of the impact craters within the region display a central bulge, bearing a well preserved stratification and a wide range of smaller morphologies like pitted cones, mounds and knobs (Franchi et al. 2013). Images acquired by HiRISE and CTX cameras on board MRO provided a comprehensive dataset in which also these small features can be easily recognized. These are tens of meters of diameter and tens of meters high, and many of them show an apical orifice. They are interpreted to have worked as pathways for subsurface fluid flow (e.g. Pondrelli et al., 2011; Rossi et al., 2008). Indeed an active underground fluid flow activity in Arabia Terra It has been recently hypothesized (e.g. Andrews-Hanna et al, 2011) , being crater central bulges a place of sulfate precipitation, due to local water table emergence (e.g. Franchi et al., 2013). To date, there is no clear explanation for occurrence of central bulges surrounded by prominent depressions in Arabia craters. In addition, in Firsoff and Crommelin craters it is possible to recognize folds and outward dipping strata on the central bulges and their surroundings. Interestingly, a few craters with a prominent bulged floor elsewhere in Arabia Terra do not display stratification and are not explainable as impact related structures as their expected pristine central peak derived by hydrocode modelling is ~2km lower and one third the diameter than the actual topography (Pozzobon et al., 2013). All these evidences are not consistent with a typical lacustrine stratigraphic environment, whether interested by sulfate precipitation or not, and suggest active deformation after or

  9. Arabia Terra

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    This image shows deposits in a crater located in Arabia Terra. Arabia is generally dust covered and dark streaks or dust avalanches are present in the crater walls. The dominant geologic process acting in this crater interior is wind erosion. The central crater deposits are eroded to form yardangs, or linear wind-sculpted hills that resemble an inverted boat hull. Deflation and abrasion are capable of eroding rock structures that are aligned parallel to wind direction. In the lower right hand side of the crater, a dark deposit has formed barchan dunes. These crescent shaped dunes have 'horns' that point downwind indicating general northwest to southeast wind direction. These dark sands probably played a role in the erosion and formation of the yardangs.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  10. Amazonian thermokarst in Danielson crater, Arabia Terra region, Mars

    NASA Astrophysics Data System (ADS)

    Baioni, Davide; Murana, Alessio; Tramontana, Mario

    2014-12-01

    This paper describe the possible ice-related landforms observed within Danielson crater which is centered at about 8°N and 353°E, in the region of southwestern Arabia Terra about 800 km south of Becquerel crater. A morphological survey of the study area through an analysis of the available Mars images was performed. The features of the landforms were investigated through an integrated analysis of Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) and Context Camera (CTX) data. Landforms interpreted as due to thermokarst processes, resembling similarly ice-related landforms found both in the cold-climate non-glacial regions of Earth, and putatively in other areas of Mars, was observed. These landforms are attributed to the presence of ground ice/ice-melting processes reflect significant climatic changes and different climatic conditions than those existing now. Moreover, they appear to display young erosional age, suggesting that are probably young, probably of Amazonian age.

  11. Fresh Shallow Valleys (FSVs) in Northern Arabia Terra, Mars

    NASA Astrophysics Data System (ADS)

    Wilson, S. A.; Howard, A. D.; Moore, J. M.

    2014-12-01

    Fresh Shallow Valleys (FSVs) on Mars are part of a growing inventory of post-Noachian landforms that may be related to late, widespread aqueous activity that occurred during a period once thought to be less favorable for precipitation and runoff. Constraining the source, magnitude, timing and duration of FSVs will provide insight into the mechanism and extent of fluvial activity on Mars and the geologic and climatic environments in which they formed. Unlike the older Noachian-Hesperian valleys that are characterized by integrated, dissected and degraded networks that cover large spatial extents, FSVs are typically narrow, short or discontinuous valleys with low drainage densities. They are generally incised no more than a few decameters, slightly degraded at multi-meter scales, and cluster in the mid-latitudes (35-50° in both hemispheres). A high concentration of FSVs occurs in Northern Arabia Terra (~33°N, 8°E), a Noachian-aged landscape characterized by broad, irregular depressions. Many of the FSVs in this region are 150+ km long and some appear to cross depressions that were likely filled with ice or water at the time of formation. Examples of broad, flat floored FSVs with incised channels could either indicate a complex history of a single flow event or multiple flow events. The occurrence of "pollywogs," fairly fresh, small (typically 2-10 km in diameter) craters with a single channel extending from the rim outward, implies overflow of the crater, the presence of a deep lake and the involvement of artesian groundwater flow. Roughly 25% of the FSVs in our northern Arabia Terra study region occur on relatively fresh crater ejecta, which may be related to formation age, topography, surface materials and (or) substrate. Ejecta with dense concentrations of FSVs average 25.5 km in diameter, have more degraded crater interiors, and well developed petal-like ejecta. Ejecta with sparse or no FSVs have radial ejecta with less distinct petals and are associated with

  12. Possible ancient giant basin and related water enrichment in the Arabia Terra province, Mars

    USGS Publications Warehouse

    Dohm, J.M.; Barlow, N.G.; Anderson, R.C.; Williams, J.-P.; Miyamoto, H.; Ferris, J.C.; Strom, R.G.; Taylor, G.J.; Fairen, A.G.; Baker, V.R.; Boynton, W.V.; Keller, J.M.; Kerry, K.; Janes, D.; Rodriguez, J.A.P.; Hare, T.M.

    2007-01-01

    A circular albedo feature in the Arabia Terra province was first hypothesized as an ancient impact basin using Viking-era information. To test this unpublished hypothesis, we have analyzed the Viking era-information together with layers of new data derived from the Mars Global Surveyor (MGS) and Mars Odyssey (MO) missions. Our analysis indicates that Arabia Terra is an ancient geologic province of Mars with many distinct characteristics, including predominantly Noachian materials, a unique part of the highland-lowland boundary, a prominent paleotectonic history, the largest region of fretted terrain on the planet, outflow channels with no obvious origins, extensive exposures of eroded layered sedimentary deposits, and notable structural, albedo, thermal inertia, gravity, magnetic, and elemental signatures. The province also is marked by special impact crater morphologies, which suggest a persistent volatile-rich substrate. No one characteristic provides definitive answers to the dominant event(s) that shaped this unique province. Collectively the characteristics reported here support the following hypothesized sequence of events in Arabia Terra: (1) an enormous basin, possibly of impact origin, formed early in martian history when the magnetic dynamo was active and the lithosphere was relatively thin, (2) sediments and other materials were deposited in the basin during high erosion rates while maintaining isostatic equilibrium, (3) sediments became water enriched during the Noachian Period, and (4) basin materials were uplifted in response to the growth of the Tharsis Bulge, resulting in differential erosion exposing ancient stratigraphic sequences. Parts of the ancient basin remain water-enriched to the present day. ?? 2007 Elsevier Inc. All rights reserved.

  13. Active aeolian processes on Mars: A regional study in Arabia and Meridiani Terrae

    USGS Publications Warehouse

    Silvestro, S.; Vaz, D.A.; Fenton, L.K.; Geissler, P.E.

    2011-01-01

    We present evidence of widespread aeolian activity in the Arabia Terra/Meridiani region (Mars), where different kinds of aeolian modifications have been detected and classified. Passing from the regional to the local scale, we describe one particular dune field in Meridiani Planum, where two ripple populations are distinguished by means of different migration rates. Moreover, a consistent change in the ripple pattern is accompanied by significant dune advancement (between 0.4-1 meter in one Martian year) that is locally triggered by large avalanche features. This suggests that dune advancement may be common throughout the Martian tropics. ?? 2011 by the American Geophysical Union.

  14. A new perspective on ancient martian volcanism: evidence for supervolcanoes in Arabia Terra, Mars

    NASA Astrophysics Data System (ADS)

    Michalski, J. R.; Bleacher, J. E.; Wright, S. P.

    2013-12-01

    While many Hesperian and Amazonian volcanic constructs on Mars are easily recognizable from their shield morphologies, significantly less is known about ancient (Noachian and earliest Hesperian) martian volcanism. Yet, heat flow in the martian crust was higher in the Noachian and therefore the planet was likely more magmatically active [1]. It is possible that Noachian volcanic constructs have largely escaped detection because higher erosion rates on ancient Mars destroyed geomorphological evidence for their existence. However, another possibility exists: some ancient volcanoes on Mars might have been of a fundamentally different character compared to well known, younger shield volcanoes because of an explosive nature of the more ancient ones. We present evidence for ancient supervolcanoes within the Arabia Terra region of Mars. Several large (~20-70 km-diameter) craters within Arabia Terra display little or no evidence for impact origins and exhibit various degrees of evidence for volcanism. These structures, which we term 'plains style caldera complexes,' show no evidence for preserved ejecta, raised rims, inverted stratigraphy, or central peaks that could be attributed to meteor impact-related processes. While it is possible that any evidence for impact origins was removed by erosion, we consider this unlikely because crater degradation generally leads to lower depth-diameter ratios [2] and these structures have high depth-diameter ratios, comparable to values for unmodified craters [3]. In fact, erosion has been low enough to preserve various pieces of evidence for volcanism associated with the structures, such as association with ridged plains lavas, possible vent structures, evidence for lava lakes in some cases, and association with sagging crust possibly related to magma migration or withdrawal. Taken together, these structures represent a newly recognized type of volcanism on Mars dominated by explosive volcanism and structural collapse. They occur within

  15. Mars Eolian Geology at Airphoto Scales: The Large Wind Streaks of Western Arabia Terra

    NASA Technical Reports Server (NTRS)

    Edgett, Kenneth S.

    2001-01-01

    More than 27,000 pictures at aerial photograph scales (1.5-12 m/pixel) have been acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) since September 1997. The pictures are valuable for testing hypotheses about geologic history and processes of Mars. Of particular interest are eolian features connected to surface albedo patterns. This work is focused on low-albedo wind streaks, some over 100 km long, in western Arabia Terra. Each streak is widest where it originates at an impact crater (typically 25-150 km diameter). The streaks taper downwind. Within the associated craters there is a lower-albedo surface that, in nearly all observed cases, includes barchan dunes indicative of transport in the same direction as the wind streaks. Upwind of the dunes there is usually an outcrop of layered material that might have served as a source for dune sand. MOC images show that the west Arabia streaks consist of a smooth-surfaced, multiple-meters-thick, mantle (smooth at 1.5 m/pixel) that appears to be superposed on local surfaces. No dunes are present, indicating that down-streak transport of sediment via saltation and traction have not occurred. Two models might explain the observed properties: (1) the streaks consist of dark silt- and clay-sized grains deflated from the adjacent crater interiors and deposited from suspension or (2) they are remnants (protected in the lee of impact crater rims) of a formerly much larger, regional covering of low albedo, smooth-surfaced mantle. The latter hypothesis is based on observation of low albedo mantled surfaces occurring south of west Arabia in Terra Meridiani. For reasons yet unknown, a large fraction of the martian equatorial regions are covered by low albedo, mesa-forming material that lies unconformably atop eroded layered and cratered terrain. Both hypotheses are being explored via continued selective targeting of new MOC images as well as analyses of the new data.

  16. Age dates of valley network drainage basins and subbasins within Sabae and Arabia Terrae, Mars

    NASA Astrophysics Data System (ADS)

    Bouley, Sylvain; Craddock, Robert A.

    2014-06-01

    The precise timing of valley network drainage basin formation is critical to understanding the history of water and climate on Mars. To determine whether there are any variations in ages within separate drainage basins and subbasins that may reflect local or regional variations in climate or resetting from resurfacing (e.g., impact ejecta or lava flows), we dated 27 basins and subbasins in Sabaea and Arabia Terrae. The age-dating basin technique we employed allowed sufficient precision to give accurate ages and shows that fluvial activity within the basins and subbasins ceased at approximately the same time around the Early Hesperian/Late Hesperian transition. Our results support the hypothesis that valley networks formed during a unique "fluvial optimum" that may have shut off gradually because of a global climate change that affected all areas simultaneously on Mars.

  17. Layered Deposits of Arabia Terra and Meridiani Planum: Keys to the Habitability of Ancient Mars

    NASA Technical Reports Server (NTRS)

    Allen, Carlton C.; Oehler, Dorothy Z.; Paris, Kristen N.; Venechuk, Elizabeth M.

    2006-01-01

    Understanding the habitability of ancient Mars is a key goal in the exploration of that planet. Evidence for conditions favorable to early life must be sought in ancient sedimentary rocks, such as those of Arabia Terra and Meridiani Planum. Arabia Terra, the northernmost extension of the ancient highlands, is dominated by cratered plains and minor ridged units. These plains extend south into the adjacent Meridiani Planum. The Opportunity rover landed in northern Meridiani, close to the border with Arabia. High resolution MOC images reveal extensive layered sequences across much of the Arabia and Meridiani region. These layers have been interpreted as eroded remnants of sedimentary rock deposits (Edgett, 2005). The layered sequences are concentrated in the SW quadrant of Arabia and in northern Meridiani. Preliminary mapping by Edgett (2005) distinguished four large scale layered sequences in the Arabia and Meridiani region. These have dimensions of hundreds to more than 1,000 km. MOLA altimetry shows that each of the sequences can attain a thickness of 200 to 400 m, with a total thickness greater than 1 km. The sequences are generally flat lying, with regional slopes of a few degrees. Much finer layering is evident within a number of craters. The plains and ridged units of the Arabia and Meridiani region were originally mapped as Noachian based on crater statistics, particularly the number of large craters (Scott and Carr, 1978). The layered sequences in the current study postdate many, but not all, of these large craters. The layered sequences have partially or totally filled a number of craters with diameters ranging from 20 to over 50 km. The topmost layered sequence, as well as the lower two sequences, have intermediate thermal inertia, as derived from THEMIS, indicative of moderate induration. The TES spectra from the lower sequences include features indicative of basalt. Some areas of the topmost sequence, which includes the Opportunity landing site, have TES

  18. Testing Formation Theories of NW Arabia Terra, Mars: New Clues from Old Craters

    NASA Astrophysics Data System (ADS)

    Robbins, S. J.; Hynek, B. M.

    2008-03-01

    Northwest Arabia Terra has topography and crater populations indicating a unique history. We directly tested two proposed formation mechanisms. Crater size-frequency and d/D ratios suggest neither scenario is easily reconcilable with the new datasets.

  19. Subsidence and Collapse Activity in Arabia Terra, Mars: Which Link with Magmatic Activity?

    NASA Astrophysics Data System (ADS)

    Mangold, N.; Howard, A. D.

    2014-12-01

    Collapsed terrains have been observed using Viking images in the northern part of Arabia Terra from Ismenius Lacus to Deuteronilus Mensae. Recent interpretations of some of these depressions as explosive volcanoes (Michalski and Bleacher, 2013) have renewed the interest for this region. However, recent observations also show the discovery in this region of a series of outflow channels named Okavango Valles (Mangold and Howard, 2013). These channels formed in the Hesperian through catastrophic flows having deposited sediments as deltas in ephemeral lakes. The source area of these channels takes place in a region of widespread depressions and local collapse pits. A continuum of landforms exists from broad depressions (~100 km in length and 100s m in depth) and sharper collapse structures (<100 km in diameter). Given the link between these depressions and the presence of outflow channels, we interpret the collapse structures as resulting from a specific lithology with volatile-rich sediments (or megaregolith) buried at depth. Collapse may be due either to the melting of subsurface ice, or subsurface flows triggered by a change in the groundwater table, or the (less likely) dissolution of buried chemical sediments. Magmatic activity is not excluded: a regionally enhanced thermal flux during the Hesperian could have triggered ground ice melting, and could have initiated subsidence subsequently, but explosive volcanism at the surface is not necessary to explain the presence of large collapsed terrains. Michalski, J. and J. Bleacher, 2013. Supervolcanoes within an ancient volcanic province in Arabia Terra, Mars, Nature, doi:10.1038/nature12482 Mangold N., and A. D. Howard, 2013. Outflow channels with deltaic deposits in Ismenius Lacus, Mars, Icarus, doi.org/10.1016/j.icarus.2013.05.040

  20. Fluvial Interpretation of Ridged Units, Northern Sinus Meridiani/Southwest Arabia Terra, Mars

    NASA Astrophysics Data System (ADS)

    Wilkinson, J.; Allen, C. C.; Oehler, D. Z.

    2007-12-01

    THEMIS, MOC, and HiRISE imagery shows features at various scales that suggest fluvial emplacement of the ridge-forming rock units exposed in northern Sinus Meridiani and southwestern Arabia Terra. The study area -- 10 N to 2 S latitude and 10 W to 8 E longitude -- spans the interface from the southern highlands to the northern plains. Numerous, linear ridges of varying width, orientation and sinuosity (mainly lower sinuosity) are suggestive of fluvial channels. Sets of features can be interpreted as braided channel reaches. Cross-cutting relationships, a common feature of channels on terrestrial fluvial plains, are ubiquitous. Many sinuous features appear as twinned parallel lines, suggesting preferential cementing of coarser channel-bank sediments. A few examples exist of features that can be interpreted as scroll bars and channel augmentation in locally narrow reaches. Layering and internal discontinuities of the Meridiani rocks are consistent with a fluvial interpretation. The regional setting of study-area units accords closely with many terrestrial basins which are occupied by fluvially emplaced sediment bodies known as megafans. Contiguous megafan surfaces (characterized by numerous channel traces, of varied orientation) cover large areas -- 1.25 million sq. km. in S. America -- with radii of hundreds of km. Megafans characteristically lie at the foot of a backing highland, from which rivers supply sediment. The ridged units on Mars lie at the foot of the southern highlands from which numerous river valleys have drained towards Meridiani Planum/southwest Arabia Terra. Further, the present regional slope is apparently away from the highlands, with downslope dimensions of hundreds of km. The low slopes of the northern Meridiani units mirror the typically low regional slopes of terrestrial megafans. Low slopes are conducive to the development of water bodies, which are numerous on some terrestrial megafans. The lacustrine model for the formation of the hematite

  1. Layered Sediments, Rampart Craters, and Potential Fluvio-Lacustrine Activity in S.W. Arabia Terra, Mars: Support for a History of Aqueous Conditions

    NASA Technical Reports Server (NTRS)

    Oehler, D. Z.; Allen, C. C.; Venechuk, E. M.; Paris, K. N.

    2007-01-01

    Arabia Terra is a unique area on Mars in that it is the only major, equatorial region characterized by high abundances of near-surface water (as measured by gamma ray and neutron spectroscopy). Vernal Crater is a 55 km-diameter structure in southwest Arabia Terra, centered at 6 N, 355.5 E. The crater includes layered sediments, potential remnants of fluvio-lacustrine activity, and indications of aeolian processes. Regional considerations, along with new THEMIS and MOC data, are being assessed to gain insight into the significance of the geomorphic units within Vernal Crater and the geologic history of SW Arabia Terra.

  2. Age-Dating Drainage Basins in Sabae and Arabia Terrae, Mars

    NASA Astrophysics Data System (ADS)

    Bouley, S.; Craddock, R. A.

    2013-12-01

    The precise timing of drainage basins is critical to understanding the climate history on Mars. One of the obvious problems with age-dating valley networks is the fact that they are small, linear features that are easily destroyed by large impact craters, thus counting craters on valley networks themselves is difficult at best. We proposed a new global study dating 27 drainage basins and subbasins in Sabaea and Arabia Terrae with the basin age-dating technique. Valley networks are contained within drainage basins, which is defined as the area that contributes water to a particular channel or set of channels . For our study, we used THEMIS (Thermal Emission Imaging System) visible images with a spatial resolution of 100 m/pixel which allow us to count craters with diameter of 1 km and larger. A digital elevation model (DEM) using 1/128 gridded Mars Orbiter Laser Altimeter (MOLA) helped us to extract the 26 basins and sub-basins drainage divides From these measurements, our study shows: (1) that all the drainages basins of a large region seem to cease their main fluvial activity at the same time at the end of the Early Hesperian epoch (~3.54 Gyr); (2) that the basin technique is the most reliable technique to do global age-dating; and (3) that there is a possible correlation between the degradation rate and the elevation. Our conclusions suggest that the main fluvial activity ceased because of a global climate change. We suppose that most of valley networks on Mars we observed today formed during the Early Hesperian and post-dated the early and late Noachian topographic features.

  3. Aram Dorsum, Candidate ExoMars Rover Landing Site: a Noachian Inverted Fluvial Channel System in Arabia Terra Mars

    NASA Astrophysics Data System (ADS)

    Balme, Matthew; Grindrod, Peter; Sefton-Nash, Elliot; Davis, Joel; Gupta, Sanjeev; Fawdon, Peter

    2016-04-01

    Much of Mars' Noachian-aged southern highlands is dissected by systems of fluvial channels and valleys > 3.7 Ga in age. Arabia Terra, lying between the southern highlands and the northern lowlands, is similarly ancient, yet apparently has few valley networks. This regional lack of valley networks only matches Noachian precipitation predictions from climate models if the Noachian climate was dry and cold [1]. In this scenario, highlands dissection was caused by transient flows of meltwater from large, regionally restricted ice-bodies. However, new results [2,3] show that Arabia Terra is not as poorly dissected as previously thought, and in fact there are extensive networks of inverted channel systems. Here, we describe an example of such a system - Aram Dorsum - which has been studied extensively as an ExoMars Rover candidate landing site. Aram Dorsum is an ~100 km long, 1-2 km wide, branching, flat-topped ridge system, in western Arabia Terra. We have mapped the system using CTX images, DEMs and other data. We interpret the ridge system to be fluvial in origin, preserved in positive relief due to infill and differential erosion; this working hypothesis is used as a conceptual framework for the study. Aram Dorsum is a branching, multi-level, contributory network, set in surrounding floodplains-like material. This demonstrates that it was a relatively long-lived, aggradational fluvial system, rather than an erosional outflow or bedrock-carved fluvial channel. Interestingly, the system shows little evidence for unconfined lateral channel migration, so there must have been significant bank stability. Aram Dorsum was therefore probably once a sizable river and, as just one example of many similar systems, is an exemplar for the middle part of a regional sediment transport system that could have extended from the southern highlands to the northern lowlands. Like Aram Dorsum, many of these other recently-recognized fluvial systems have an origin more consistent with

  4. Geometry, stratigraphy and evidences for fluid expulsion within Crommelin crater deposits, Arabia Terra, Mars

    NASA Astrophysics Data System (ADS)

    Franchi, F.; Rossi, A. P.; Pondrelli, M.; Cavalazzi, B.

    2014-03-01

    Conical mounds and furrows are widely interpreted as the morphological evidences of fluids expulsion on the martian surface. In the Crommelin crater (equatorial Arabia Terra) furrows and conical mounds are exhumed within light-toned equatorial layered deposits (ELDs). Aim of this paper is to describe these landforms and discuss their potential relations with water upwelling in Crommelin area. A comparative study of some of the morphologies hosted in the Crommelin area deposits have been performed by using multiple datasets (CTX, HRSC, MOLA, HiRISE). Then examples of spring and conical mounds on Earth was examined for comparison with analog structures on Mars. In this work thickness and geometries of the crater filling sediment packages have been calculated. Stratigraphic contacts and relations have been also reported in Crommelin area revised geological map, and mound clusters, potentially fluid-related morphologies, from Crommelin, Firsoff and Southern crater have been detailed. The morphometric and morphological analyses revealed that mounds and other structures occur where the ELDs are thicker and crudely layered. In addition, orthorectified imagery and high-resolution topography indicated the presence of conical mounds within the upper portion of ELDs near the craters rims. Mounds show apical holes and are linked to elongated structures resembling veins and dikes. Elongated structures (furrows) and concentric strata pattern that we refer to as ridge-and-through, were described inside to Crommelin crater. MOLA-based DEMs revealed that these morphologies developed within a flat topography and are inconsistent with gravitative processes. The results suggest that the inferred sediments package was likely part of an extensive zone of groundwater upwelling. This long-wavelength flow controlled water and sediments supply into the study area, probably during a major climate shift. Fluid expulsion processes were recognized as a relevant process in the formation of these

  5. Low Albedo Surfaces and Eolian Sediment: Mars Orbiter Camera Views of Western Arabia Terra Craters and Wind Streaks

    NASA Technical Reports Server (NTRS)

    Edgett, Kenneth S.

    2001-01-01

    High spatial resolution (1.5 to 12 m/pixel) Mars Global Surveyor Mars Orbiter Camera images obtained September 1997 through June 2001 indicate that the large, dark wind streaks of western Arabia Terra each originate at a barchan dune field on a crater floor. The streaks consist of a relatively thin coating of sediment deflated from the dune fields and their vicinity. This sediment drapes a previous mantle that more thickly covers nearly all of western Arabia Terra. No dunes or eolian bedforms are found within the dark wind streaks, nor do any of the intracrater dunes climb up crater walls to provide sand to the wind streaks. The relations between dunes, wind streak, and subjacent terrain imply that dark-toned grains finer than those which comprise the dunes are lifted into suspension and carried out of the craters to be deposited on the adjacent terrain. Such grains are most likely in the silt size range (3.9-62.5 micrometers). The streaks change in terms of extent, relative albedo, and surface pattern over periods measured in years, but very little evidence for recent eolian activity (dust plumes, storms, dune movement) has been observed.

  6. Sedimentary Rocks and Methane - Southwest Arabia Terra

    NASA Technical Reports Server (NTRS)

    Allen, Carlton C.; Oehler, Dorothy Z.; Venechuk, Elizabeth M.

    2006-01-01

    We propose to land the Mars Science Laboratory in southwest Arabia Terra to study two key aspects of martian history the extensive record of sedimentary rocks and the continuing release of methane. The results of this exploration will directly address the MSL Scientific Objectives regarding biological potential, geology and geochemistry, and past habitability.

  7. Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III; Crown, David A.

    2009-01-01

    Geologic mapping studies at the 1:1M-scale are being used to assess geologic materials and processes that shape the highlands along the Arabia Terra dichotomy boundary. In particular, this mapping will evaluate the distribution, stratigraphic position, and lateral continuity of compositionally distinct outcrops in Mawrth Vallis and Nili Fossae as identified by spectral instruments currently in orbit. Placing these landscapes, their material units, structural features, and unique compositional outcrops into spatial and temporal context with the remainder of the Arabia Terra dichotomy boundary may provide constraints on: 1) origin of the dichotomy boundary, 2) paleo-environments and climate conditions, and 3) various fluvial-nival modification processes related to past and present volatile distribution and their putative reservoirs (aquifers, lakes and oceans, surface and ground ice) and the influences of nearby volcanic and tectonic features on hydrologic processes in these regions. The results of this work will include two 1:1M scale geologic maps of twelve MTM quadrangles (Mawrth Vallis - 20022, 20017, 20012, 25022, 25017, and 25012; and Nili Fossae - 20287, 20282, 25287, 25282, 30287, 30282).

  8. Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars: Introductory Report

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III; Crown, David A.

    2008-01-01

    Geologic mapping studies at the 1:1M-scale will be used to characterize geologic processes that have shaped the highlands along the Arabia Terra dichotomy boundary. In particular, this mapping will evaluate the distribution, stratigraphic position, and lateral continuity of compositionally distinct outcrops in Mawrth Vallis and Nili Fossae as identified by spectral instruments currently in orbit. Placing these landscapes, their material units, structural features, and unique compositional outcrops into spatial and temporal context with the remainder of the Arabia Terra dichotomy boundary will provide the ability to: 1) further test original dichotomy formation hypotheses, 2) constrain ancient paleoenvironments and climate conditions, and 3) evaluate various fluvial-nival modification processes related to past and present volatile distribution and their putative reservoirs (aquifers, lakes and oceans, surface and ground ice) and the influences of nearby volcanic and tectonic features on hydrologic processes in these regions. The result will be two 1:1M scale geologic maps of twelve MTM quadrangles (Mawrth Vallis - 20022, 20017, 20012, 25022, 25017, and 25012; and Nili Fossae - 20287, 20282, 25287, 25282, 30287, 30282).

  9. The sedimentology and dynamics of crater-affiliated wind streaks in western Arabia Terra, Mars and Patagonia, Argentina

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Tanaka, K.L.; Yamamoto, A.; Berman, D.C.; Zimbelman, J.R.; Kargel, J.S.; Sasaki, S.; Jinguo, Y.; Miyamoto, H.

    2010-01-01

    Wind streaks comprise recent aeolian deposits that have been extensively documented on Venus, Earth and Mars. Martian wind streaks are among the most abundant surface features on the planet and commonly extend from the downwind margins of impact craters. Previous studies of wind streaks emerging from crater interior deposits suggested that the mode of emplacement was primarily related to the deposition of silt-sized particles as these settled from plumes. We have performed geologic investigations of two wind streaks clusters; one situated in western Arabia Terra, a region in the northern hemisphere of Mars, and another in an analogous terrestrial site located in southern Patagonia, Argentina, where occurrences of wind streaks emanate from playas within maar craters. In both these regions we have identified bedforms in sedimentary deposits on crater floors, along wind-facing interior crater margins, and along wind streaks. These observations indicate that these deposits contain sand-sized particles and that sediment migration has occurred via saltation from crater interior deposits to wind streaks. In Arabia Terra and in Patagonia wind streaks initiate from crater floors that contain lithic and evaporitic sedimentary deposits, suggesting that the composition of wind streak source materials has played an important role in development. Spatial and topographic analyses suggest that regional clustering of wind streaks in the studied regions directly correlates to the areal density of craters with interior deposits, the degree of proximity of these deposits, and the craters' rim-to-floor depths. In addition, some (but not all) wind streaks within the studied clusters have propagated at comparable yearly (Earth years) rates. Extensive saltation is inferred to have been involved in its propagation based on the studied terrestrial wind streak that shows ripples and dunes on its surface and the Martian counterpart changes orientation toward the downslope direction where it

  10. Fresh Shallow Valleys in Northern Arabia Terra: Evidence for a Late, Widespread Period of Aqueous Activity on Mars

    NASA Astrophysics Data System (ADS)

    Wilson, S. A.; Howard, A. D.; Moore, J. M.; Grant, J. A., III

    2015-12-01

    Concentrations of fresh shallow valleys (FSVs) on Mars occur between ~30-45° in both hemispheres as well as near the equator (e.g., Gale crater and vicinity). FSVs in the northern hemisphere occur along the dichotomy boundary, with the highest concentration in northern Arabia Terra from 35-40°N between 0-20ºE. In this region, FSVs developed both on and away from ejecta of relatively fresh craters, making the direct association between impact processes and formation less likely. Crater statistics and cross-cutting relationships indicate the formation of FSVs terminated prior to about 1.4 Ga, suggesting they may be contemporaneous with alluvial fan and delta formation in the equatorial and mid-latitudes. Many FSV systems are 150+ km long, and in several cases appear to cross depressions that were likely filled with ice or water during FSV formation. Most FSV systems could have formed from a single episode of erosion but incision of the main channel in some locations may imply episodic formation. One long valley system in N. Arabia Terra with an incised channel (100 m wide, up to 10 m deep) yields formative discharges in the range of 100-200 m3/s assuming sand sized particles and a flow depth of 0.25 m, consistent with formation via snowmelt. The grain size is unknown, therefore discharges could range from 10s m3/s for active transport of fine sand to 1000 m3/s for gravel sized grains. Approximately 25 small craters (diameters ranging from ~2-10 km) have single channels extending outward from their rim, implying overflow of the crater and the possible presence of a deep lake. Widespread occurrence of FSVs, their similar morphology, and modest state of degradation is consistent with most forming during one or more global intervals of favorable climate, likely through snowmelt from surface or sub-ice flows during the Hesperian.

  11. Equatorial Layered Deposits in Arabia Terra, Mars: Facies and Process Variability

    NASA Astrophysics Data System (ADS)

    Pondrelli, M.; Rossi, A.; van Gasselt, S.; Le Deit, L.; Glamoclija, M.; Cavalazzi, B.; Franchi, F.; Fueten, F.; Hauber, E.; Zegers, T.

    2012-12-01

    Genetic mechanisms proposed to explain Equatorial Layered Deposits (ELDs) formation include subglacial volcanism, aeolian/airfall, lacustrine, lacustrine/volcanic and spring-fed deposition. ELDs have been frequently shown to consist of sulfates (e.g. Gendrin et al., 2005) that might form as a response to evaporation in a playa environment (Hoefen et al., 2003) or during spring precipitation (e.g. Allen and Oehler, 2008; Rossi et al., 2008). The importance of groundwater-dominated hydrological systems was proposed to explain the formation of light-toned deposits in Meridiani Planum and Arabia Terra (e.g. Andrews-Hanna et al. 2007). Additionally, fluid expulsion processes have been invoked to explain the formation of mounds within the light-toned deposits in Arabia Terra (Allen and Oehler, 2008; Rossi et al., 2008; Pondrelli et al., 2011). Potential for habitable conditions of both playa and spring-related settings (Cavalazzi et al., 2007; Glamoclija et al., 2011) coupled with the high preservation potential within sulfates (Panieri et al., 2010), make these deposits a good candidate to understand the potential past habitability of the planet. In order to investigate ELDs genesis, an area in the vicinity of Firsoff crater, where ELDs are present within and outside the craters, was selected for geological mapping and analysis of the landforms and their association using the available dataset, including CRISM in order to infer ELDs composition. Within Firsoff crater, ELDs form a bulge that can be estimated to be at least a few hundred meters thick, while, outside the craters, ELDs form flat-lying deposits. Although heavily eroded by wind and carved by yardangs, several morphologies within the ELDs in the craters seem to be depositional, which would exclude that the entire Firsoff basin had been originally filled by ELDs. Within craters, ELDs consist of roughly meter thick layers draping and onlapping the substratum. They appear affected by polygonal patterns with no

  12. A Sedimentary Platform in Margaritifer Sinus, Meridiani Terra, and Arabia?

    NASA Technical Reports Server (NTRS)

    Howard, A. D.; Moore, J. M.; Irwin, R. P., III; Craddock, R. A.

    2005-01-01

    The Margaritifer-Meridiani-Arabia highlands-lowlands (H-L) transition has long been recognized as the most fluvially dissected region of Mars. However, the geomorphic evolution of this region remains enigmatic, particularly the origin of the layered deposits of Meridiani Terra and Arabia. We suggest that a portion of this regional slope served as a fluvial depositional platform during the late Noachian.

  13. Thinking Like a Wildcatter: Prospecting for Methane in Arabia Terra, Mars

    NASA Technical Reports Server (NTRS)

    Allen, C. C.; Oehler, D. Z.

    2005-01-01

    Methane has been detected in the martian atmosphere at a concentration of approximately 10 ppb. The lifetime of such methane against decomposition by solar radiation is approximately 300 years, strongly suggesting that methane is currently being released to the atmosphere. By analogy to Earth, possible methane sources on Mars include active volcanism, hot springs, frozen methane clathrates, thermally-matured sedimentary organic matter, and extant microbial metabolism. The discovery of any one of these sources would revolutionize our understanding of Mars.

  14. Candidate Landing Site for the Mars Science Laboratory: Vernal Crater, S.W. ARabia Terra

    NASA Technical Reports Server (NTRS)

    Paris, K. N.; Allen, C. C.; Oehler, D. Z.

    2007-01-01

    In the fall of 2009, the Mars Science Laboratory (MSL) will be launched to Mars. The purpose of this mission is to assess biologic potential and geology and to investigate planetary processes of relevance to past habitability. MSL will be able to provide visual, chemical, radiation, and environmental data with its suite of instruments [1]. In order to be selected for the MSL landing site, certain engineering requirements must be met [1] and the area should contain geologic features suggestive of past habitability, so that the overriding science goal of the mission will be attained. There are a total of 33 proposed landing sites as of the first MSL Landing Site Workshop held in Pasadena, CA from May 31st to June 2nd, 2006 [1]. There will be an opportunity to gather high resolution visual and hyperspectral data on all proposed landing sites from the now-orbiting Mars Reconnaissance Orbiter (MRO) which entered martian orbit and began its main science phase in November of 2006 [2]. The data being gathered are from: the high resolution imaging science experiment (HiRISE), the context (CTX) camera and the compact reconnaissance imaging spectrometer (CRISM) onboard the spacecraft. The footprints of these instruments are centered on a single point, and each proposer must submit these coordinates, along with the coordinates of the proposed landing ellipse. Data from these instruments, along with new MOC images and THEMIS mosaics, will be used to enhance our understanding of the geologic and engineering parameters of each site.

  15. Widespread Layers in Arabia Terra: Implications for Martian Geologic History

    NASA Technical Reports Server (NTRS)

    Venechuk, Elizabeth M.; Oehler, D. Z.

    2006-01-01

    Layered rocks in Arabia Terra have been the focus of several recent papers. Studies have focused on the layers found in crater basins located in the southwest portion of the region. However, Mars Orbiter Camera (MOC) images have identified layered deposits across the region. Terrestrial layered rocks are usually sedimentary, and often deposited in water. Thus extensive layered sequences in Arabia Terra may indicate locations of past, major depositional basins on Mars. Other mechanisms can also create layered rocks, or the appearance of layered rocks, including volcanism (both lava flows and ash falls), wind-blown deposits, and wave-cut terraces at shorelines. By identifying where in the region layers occur, and classifying the layers according to morphology and albedo, past depositional environments may be identified. Arabia Terra is characterized by heavily cratered Noachian plains, as well as a rise from -4000 m in the northwest to 4000 m in the southeast (Mars Orbital Laser Altimeter [MOLA] datum). This slope may have provided a constraint on sediment deposition and thus layer formation. While most of the region is Noachian in age, a significant percentage of the area is identified as Hesperian. Although the history of the Arabia Terra initially seems to be straightforward cratered plains with several younger units atop them analysis of high-resolution imagery may reveal a more complex history.

  16. Discovery of a Plains Caldera Complex and Extinct Lava Lake in Arabia Terra, Mars: Implications for the Discovery of Additional Highland Volcanic Source Regions

    NASA Technical Reports Server (NTRS)

    Bleacher, Jacob; Michalski, Joseph

    2012-01-01

    Several irregularly shaped topographic depressions occur near the dichotomy boundary in northern Arabia Terra, Mars. The geomorphology of these features suggests that they formed by collapse, opposed to meteor impact. At least one depression (approx.55 by 85 km) displays geologic features indicating a complex, multi-stage collapse history. Features within and around the collapse structure indicate volcanic processes. The complex occurs within Hesperian ridged plains of likely volcanic origin and displays no crater rim or evidence for ejecta. Instead the depression consists of a series of circumferential graben and down-dropped blocks which also display upper surfaces similar to ridged plain lavas. Large blocks within the depression are tilted towards the crater center, and display graben that appear to have originally been linked with circumferential graben outside of the complex related to earlier collapse events. A nearly 700 m high mound exists along a graben within the complex that might be a vent. The deepest depression displays two sets of nearly continuous terraces, which we interpret as high-stands of a drained lava lake. These features appear similar to the black ledge described during the Kilauea Iki eruption in 1959. A lacustrine origin for the terraces seems unlikely because of the paucity of channels found in or around the depression that could be linked to aqueous surface processes. In addition, there is no obvious evidence for lacustrine sediments within the basin. Together with the presence of significant faulting that is indicative of collapse we conclude that this crater complex represents a large caldera formed in the Late Noachian to Early Hesperian. Other linear and irregular depressions in the region also might be linked to ancient volcanism. If that hypothesis is correct, it suggests that northern Arabia Terra could contain a large, previously unrecognized highland igneous province. Evacuation of magma via explosive and effusive activity

  17. Geological Time on Display in Arabia Terra

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    This scene from the dust covered plains of eastern Arabia Terra portrays a range of geological time. Three craters at the center of the image capture some of this range. Two have the classic bowl-shape of small, relatively recent craters while the one just to the north has seen much more history. Its rim has been scoured away by erosion and its floor has been filled in by material likely of a sedimentary nature. The channels that wind through the scene may be the oldest features present while the relatively dark streaks scattered about could have been produced in the past few years or even months as winds remove a layer of dust to reveal darker material below.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  18. Knobby terrain in Northern Arabia Terra

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 25 April 2002) The Science This THEMIS visible image shows a region in northern Arabia Terra near 44o N, 322o W (38o E). Knobby or 'scabby' plains units that mantle and modify a pre-existing cratered surface dominate the unusual landscape in this region. Several large (5-8 km diameter) impact craters seen in the upper left of the image have been extensively modified since their initial formation. The rims of these craters can still be seen, but the ejecta deposits and the surrounding plains have been buried by a layer of material. This mantling layer has itself been modified to produce a pitted, knobby surface. Circular depressions of all sizes, presumably the remnants of impact craters, are filled with smooth deposits. In some places large regions have been covered by this smooth material; an example can be seen in the lower right portion of this image. In many cases the impact craters have been extensively modified prior to their being filled. This modification indicates an erosion process that has removed material from the walls to produce shapes that vary from circular with crisp rims, to circular with no rims, to oblong and elliptical forms, and finally to irregular shapes whose initial circular outline can barely be detected. The slope of the channel at the top of the image has an unusual deposit of material that occurs preferentially on the cold, north-facing slope. Similar deposits are seen frequently at mid-northern and southern latitudes on Mars, and have a characteristic, rounded boundary that typically occurs at approximately the same distance below the ridge crest. It has been suggested that these deposits once draped the entire surface and have since been removed from all but the cold north-facing slopes. The presence and removal of ground ice may play an important role in the formation of this layer, as well as the knobby terrain and unusual features seen in this image. The StoryThere's no way these impact craters are in their original

  19. Peleolakes and impact basins in southern Arabia Terra, including Meridiani Planum: Implications for the formation of hematite deposits on Mars

    USGS Publications Warehouse

    Newsom, Horton E.; Barber, C.A.; Hare, T.M.; Schelble, R.T.; Sutherland, V.A.; Feldman, W.C.

    2003-01-01

    The hematite deposit in Meridiani Planum was selected for a Mars Exploration Rover (MER) landing site because water could be involved in the formation of hematite, and water is a key ingredient in the search for life. Our discovery of a chain of paleolake basins and channels along the southern margin of the hematite deposits in Meridiani Planum with the presence of the strongest hematite signature adjacent to a paleolake basin, supports the possible role of water in the formation of the hematite and the deposition of other layered materials in the region. The hematite may have formed by direct precipitation from lake water, as coatings precipitated from groundwater, or by oxidation of preexisting iron oxide minerals. The paleolake basins were fed by an extensive channel system, originating from an area larger than Texas and located south of the Schiaparelli impact basin. On the basis of stratigraphic relationships, the formation of channels in the region occurred over much of Mars' history, from before the layered materials in Meridiani Planum were deposited until recently. The location of the paleolake basins and channels is connected with the impact cratering history of the region. The earliest structure identified in this study is an ancient circular multiringed basin (800-1600 km diameter) that underlies the entire Meridiani Planum region. The MER landing site is located on the buried northern rim of a later 150 km diameter crater. This crater is partially filled with layered deposits that contained a paleolake in its southern portion. Copyright 2003 by the American Geophysical Union.

  20. Comparing Crustal Magnetism of Terra Meridiani and Terra Cimmeria, Mars

    NASA Astrophysics Data System (ADS)

    French, R. A.; Jurdy, D. M.

    2014-12-01

    Terra Meridiani displays remanent crustal magnetization, roughly symmetric and coherent over long distances, that has been interpreted by some workers as resulting from seafloor spreading. A detailed magnetization map of this region, located at 0º, 0º ±20º, will be compared with that of Terra Cimmeria (-40º, 180º) which hosts Mars' most intense and continuous magnetization. Mars Global Surveyor magnetometer (MGS MAG) data from mapping altitude (~400km) was downward continued to the surface. Data from the MGS aerobraking phase contains tracks in Terra Meridiani at altitudes between 110-190 km, revealing localized persistent Br signatures between -268 and 278 nT, with standard deviations of 24 and 17 nT, respectively. These signatures coincide with areas of strongest magnetization on the downward continued map at corresponding altitudes. However, several uncorrelated small-scale pockets of magnetization that appear in the aerobraking dataset may be attributed to shorter wavelength signals or noise. Positive and negative sources in Terra Meridiani show comparable decay with altitude. Similarly, sources in Terra Cimmeria resemble this decay. By extrapolating into the subsurface, we estimate the source depths for both regions and observe that Terra Meridiani has shallower sources than Terra Cimmeria. The strongest magnetization in Terra Meridiani lies along the 4,600 km diameter outer ring of the Chryse basin. A similar association occurs in Terra Cimmeria along the outer rings of the Sirenum basin. The decay of magnetization intensity with altitude, crustal composition, and crustal thickness estimates will be used to create simple models of magnetic sources for Terra Meridiani.

  1. Radar Scattering Properties of Terra Meridiani, Mars

    NASA Astrophysics Data System (ADS)

    Larsen, K. W.; Haldemann, A. F.; Jurgens, R. F.; Slade, M. A.; Arvidson, R. E.

    2002-12-01

    A series of fourteen radar observations of Mars were made during the 2001 opposition. Four of these observation tracks passed over Terra Meridiani, a prime candidate landing site for one of the 2003 Mars Exploration Rover missions. Observations were conducted using X-band (3.5 centimeter wavelength) radar transmitted with a pseudo-random binary phase encoding which, combined with the frequency resolution of the processing FFT, yields a maximum spatial resolution of approximately five kilometers. Actual spatial resolution is coarser than this (between five and twenty kilometers) due to signal-to-noise considerations that predicated longer integration times as well as greater planetary ranges for the off-opposition observations. We have processed the Terra Meridiani data in stages, beginning with one-dimensional sub-radar track profiles and culminating with four-station interferometry. Not all observations were amendable to the full four-station interferometry, due to technical issues, but were processed with a minimum of two stations to remove the spatial ambiguities inherent to radar observations. Our processing yields one- and two-dimensional maps of the surface reflectivity along the radar track. We extract scattering data for points along the sub-radar track, where the angle in incidence varies most, and model the scattering function. The multi-station reflectivity data is also modeled according to the Hagfors scattering model to extract two-dimensional maps of RMS roughness and dielectric constant. The RMS roughness data for the Terra Meridiani landing sites shows the local surface slopes to be less than 3 degrees, on the scale of tens of wavelengths. An enhanced dielectric constant is apparent over Terra Meridiani that is spatially correlated with the MGS detected hematite deposits. The level of the enhancement is consistent with the inclusion of 10-15 percent hematite, according to a weighted dielectric or PVL model. Integral to our processing, and new to

  2. Extension Across Tempe Terra, Mars from MOLA Topographic Measurements

    NASA Technical Reports Server (NTRS)

    Harrington, B. W.; Phillips, R. J.; Golombek, M. P.

    1999-01-01

    Previously, methods of estimating the extension across grabens and rifts on Mars by necessity relied on photogeologic methods such as shadow measurement, crater ellipticity, or photoclinometry. With the new data being returned by the Mars Global Surveyor, specifically from the Mars Orbital Laser Altimeter (MOLA), it is now possible to directly measure the depths of these structures and therefore to estimate more accurately the amount of extension. Here we provide an example of this new approach in the Tempe Terra region. Additional information is contained in the original extended abstract.

  3. Light-Toned, Layered Outcrops of Northern Terra Meridiani Mars: Viking, Phobos 2, and Mars Global Surveyor Observations

    NASA Technical Reports Server (NTRS)

    Edgett, Kenneth S.

    2002-01-01

    System (PDS). The main body of data examined were Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images acquired through 30 September 2002. The data also 2 include Viking orbiter images, a Phobos 2 Termoscan image, MGS Mars Orbiter Laser Altimeter (MOLA) topographic observations, and the products of published Viking Infrared Thermal Mapper (IRTM) and Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) analyses. Through September 2002, over 126,000 MOC images had been acquired, and greater than 600 of the MOC narrow angle (1.5-12 m/pixel) images occur within the portions of Terra Meridiani and southwestern Arabia Terra.

  4. Vernal Crater, SW Arabia Terra: MSL Candidate with Extensively Layered Sediments, Possible Lake Deposits, and a Long History of Subsurface Ice

    NASA Technical Reports Server (NTRS)

    Oehler, Dorothy Z.; Allen, Carlton C.

    2007-01-01

    Vernal Crater is a Mars Science Laboratory (MSL) landing site candidate providing relatively easy access to extensively layered sediments as well as potential lake deposits. Sediments of Vernal Crater are 400-1200 m below those being investigated by Opportunity in Meridiani Planum, and as such would allow study of significantly older geologic units, if Vernal Crater were selected for MSL. The location of Vernal Crater in SW Arabia Terra provides exceptional scientific interest, as rampart craters and gamma-ray spectrometer (GRS) data from the region suggest a long history of ice/fluids in the subsurface. The potential value of this MSL candidate is further enhanced by reports of atmospheric methane over Arabia, as any insight into the source of that methane would significantly increase our understanding of Mars. Finally, should MSL survive beyond its prime mission, the gentle slope within Vernal Crater would provide a route out of the crater for study of the once ice/fluid-rich plains.

  5. Ancient Giant Basin/Aquifer System in the Arabia Region, Mars

    NASA Technical Reports Server (NTRS)

    Dohm, James M.; Barlow, Nadine; Williams, Jean-Pierre; Baker, Victor R.; Anderson, Robert C.; Boynton, William V.; Fairen, Alberto G.; Hare, Trent M.

    2004-01-01

    Ancient geologic/hydrologic phenomena on Mars observed through the magnetic data [1,2] provide windows to the ancient past through the younger Argyre and Hellas impacts [e.g., 3,4], the northern plains basement [5], and the Tharsis and Elysium magmatic complexes (recently referred to as superplumes [6,7]). These signatures, coupled with highly degraded macrostructures (tectonic features that are tens to thousands of km-long [8]), reflect an energetic planet during its embryonic development (.5 Ga or so of activity) with an active dynamo and magnetosphere [1,2,6]. One such window into the ancient past occurs northwest of the Hellas impact basin in Arabia Terra. Arabia Terra is one of the few water-rich equatorial regions of Mars, as indicated through impact crater [9] and elemental [10,11] information. This region records many unique traits, including stratigraphy, topography, cratering record, structural character, geomorphology, and geophysical, elemental, albedo, and thermal inertia signatures. We interpret these to collectively indicate a possible ancient giant impact basin that later became an important aquifer, as it provided yet another source of water for the formation of putative water bodies that occupied the northern plains [12,13] and addresses possible water-related characteristics that may be observed at the Opportunity landing site. This basin is antipodal to Tharsis and estimated to be at least 3,000 km in diameter.

  6. Braided alluvial fan in the Terra Sirenum region, Mars

    NASA Astrophysics Data System (ADS)

    Adeli, S.; Hauber, E.; Le Deit, L.; Kleinhans, M. G.; Platz, T.; Fawdon, P.; Jaumann, R.

    2015-10-01

    Here we report the presence of an Amazonian-aged outflow channel located on the rim of the Ariadnes Colles basin (37°S/178°E) that has an alluvial fan on its downstream part. The study area is located in the Noachian highlands of Terra Sirenum, the site of a large hypothesized paleolake [3]. This so-called Eridania lake existed during the Late Noachian -Early Hesperian and drained into Ma'adim Vallis, one of the largest valleys on Mars. The Ariadnes Colles basin was part of the Eridania paleolake and hosted later a closed lake.

  7. Identifying the Pre-Tharsis Structures Associated with the Terra Sirenum Region, Mars

    NASA Astrophysics Data System (ADS)

    Anderson, R. C.; Dohm, J. M.; Robbins, S.; Schroeder, J.

    2014-07-01

    The Terra Sirenum region contains some of the oldest stratigraphic units found on Mars. Examination of the structures and units provides an excellent window into clarifying the processes that influenced the early geologic evolution of Mars.

  8. Terra Sirenum: Window into Pre-Tharsis and Tharsis Phases of Mars Evolution

    NASA Astrophysics Data System (ADS)

    Anderson, R. C.; Dohm, J. M.; Robbins, S.; Hynek, B.; Andrews-Hanna, J.

    2012-03-01

    The Terra Sirenum region contains some of the oldest stratigraphic units on Mars. Detailed examination of the structures and units provides an excellent window into identifying the processes that influenced the early geologic evolution of Mars.

  9. MOLA Topography of Small Volcanoes in Tempe Terra and Ceraunius Fossae, Mars: Implications for Eruptive Styles

    NASA Technical Reports Server (NTRS)

    Wong, M. P.; Sakimoto, S. E. H.; Garvin, J. B.

    2001-01-01

    We use Mars Orbiter Laser Altimeter (MOLA) data to measure small volcanoes in the Tempe Terra and Ceraunius Fossae regions of Mars. We find that previous geometry estimates based on imagery alone are inaccurate, but MOLA data support image-based interpretations of eruptive style. Additional information is contained in the original extended abstract.

  10. East Arabia Landforms

    NASA Technical Reports Server (NTRS)

    2005-01-01

    11 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows two small mesas, a hill, and other landforms in the highly-eroded landscape of eastern Arabia Terra.

    Location near: 30.0oN, 295.0oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  11. Hematite and Etched Terrain Distribution in Terra Meridiani, Mars

    NASA Astrophysics Data System (ADS)

    Koeppen, W. C.; Arvidson, R. E.; Seelos, F. P.

    2002-12-01

    Analyses of TES-based bolometric albedo, thermal inertia, and spectral emissivity-derived hematite index for the Hematite region in Terra Meridiani (centered at 1.5 deg S and 3.0 deg W) indicate the terrain to be homogenous at resolutions of 3 km per pixel. In contrast, MOC NA frames with a maximum resolution of ~1.5 meters per pixel show that though the Hematite region is composed primarily of smooth, dark, pervasive dune-forms, there are also exposures of a ubiquitous bright material. This high albedo etched unit is interpreted to be a resistant substrate that extends beyond the borders of the overlying hematite-bearing plains. In order to quantify the relative superficial abundance of bright substrate and dark plains, we conduct high-resolution mapping of the hematite-bearing unit using MOC NA frames processed to ISIS level 2 (map projected with units proportional to radiance on sensor). As an illustrative example, MOC NA E03-01763 exhibits the etched unit in three typical settings: young crater rims, older craters which have lost much of their topographic signature but retain bright rims, and intercrater plains underlying dark, motley dunes. By area, 9.1% of the frame consists of bright material distributed uniformly across the scene. In general, MOC frames from the Hematite unit exhibit bright materials with an areal coverage ranging from 3% to 12%. This analysis demonstrates that the Mars Exploration Rover will be able to perform in-situ analyses of both the dark, hematite-bearing plains and the bright substrate over the course of the primary 90 sol mission.

  12. TERRA.

    ERIC Educational Resources Information Center

    Locke, Kirsty

    1997-01-01

    TERRA (Teaching Ecological Responsibility, Recreation, and Adventure) is an integrated, one-semester, four-course program in environmental science, environmental English, independent geography, and outdoor education for grades 11 and 12 in New Liskeard, Ontario. Program activities include outdoor adventure, environmental research projects,…

  13. The Origin of the Terra Meridiani Sediments: Volatile Transport and the Formation of Sulfate Bearing Layered Deposits on Mars

    NASA Technical Reports Server (NTRS)

    Niles, P.B.

    2008-01-01

    The chemistry, sedimentology, and geology of the Meridiani sedimentary deposits are best explained by eolian reworking of the sublimation residue of a large scale ice/dust deposit. This large ice deposit was located in close proximity to Terra Meridiani and incorporated large amounts of dust, sand, and SO2 aerosols generated by impacts and volcanism during early martian history. Sulfate formation and chemical weathering of the initial igneous material is hypothesized to have occurred inside of the ice when the darker mineral grains were heated by solar radiant energy. This created conditions in which small films of liquid water were created in and around the mineral grains. This water dissolved the SO2 and reacted with the mineral grains forming an acidic environment under low water/rock conditions. Subsequent sublimation of this ice deposit left behind large amounts of weathered sublimation residue which became the source material for the eolian process that deposited the Terra Meridiani deposit. The following features of the Meridiani sediments are best explained by this model: The large scale of the deposit, its mineralogic similarity across large distances, the cation-conservative nature of the weathering processes, the presence of acidic groundwaters on a basaltic planet, the accumulation of a thick sedimentary sequence outside of a topographic basin, and the low water/rock ratio needed to explain the presence of very soluble minerals and elements in the deposit. Remote sensing studies have linked the Meridiani deposits to a number of other martian surface features through mineralogic similarities, geomorphic similarities, and regional associations. These include layered deposits in Arabia Terra, interior layered deposits in the Valles Marineris system, southern Elysium/Aeolis, Amazonis Planitia, and the Hellas basin, Aram Chaos, Aureum Chaos, and Ioni Chaos. The common properties shared by these deposits suggest that all of these deposits share a common

  14. Blueberries on Earth and Mars: Correlations Between Concretions in Navajo Sandstone and Terra Meridiani on Mars.

    NASA Astrophysics Data System (ADS)

    Mahaney, W. C.; Milner, M. W.; Netoff, D.; Dohm, J.; Kalm, V.; Krinsley, D.; Sodhi, R. N.; Anderson, R. C.; Boccia, S.; Malloch, D.; Kapran, B.; Havics, A.

    2008-12-01

    Concretionary Fe-Mn-rich nodular authigenic constituents of Jurassic Navajo sandstone (moki marbles) bear a certain relationship to similar concretionary forms ('blueberries') observed on Mars. Their origin on Earth is considered to invoke variable redox conditions with underground fluids penetrating porous quartz-rich sandstone leading to precipitation of hematite and goethite-rich material from solution, generally forming around a central nucleus of fine particles of quartz and orthoclase, recently verified by XRD and SEM-EDS analyses. At the outer rim/inner nucleus boundary, bulbous lobes of fine-grained quartz often invade and fracture the outer rim armored matrix. The bulbous forms are interpreted to result from fluid explusion from the inner concretionary mass, a response to pressure changes accompanying overburden loading. Moki marbles, harder than enclosing rock, often weather out of in situ sandstone outcrops that form a surface lag deposit of varnished marbles that locally resemble desert pavement. The marbles appear morphologically similar to 'blueberries' identified on the martian surface in Terra Meridiani through the MER-1 Opportunity rover. On Earth, redox fluids responsible for the genesis of marbles may have emanated from deep in the crust (often influenced by magmatic processes). These fluids, cooling to ambient temperatures, may have played a role in the genesis of the cemented outer rim of the concretions. The low frequency of fungi filaments in the marbles, contrasts with a high occurrence in Fe-encrusted sands of the Navajo formation [1], indicating that microbial content is of secondary importance in marble genesis relative to the fluctuating influx of ambient groundwater. Nevertheless, the presence of filaments in terrestrial concretions hints at the possibility of discovering fossil/extant life on Mars, and thus should be considered as prime targets for future reconnaissance missions to Mars. 1] Mahaney, W.C., et al. (2004), Icarus, 171, 39-53.

  15. Water Indicators in Sirenum Terra and Around the Argyre Impact Basin, Mars

    NASA Technical Reports Server (NTRS)

    Stern, J. G.; Frey, H. V.

    2004-01-01

    This study examines the relationships between three temporally distinct indicators of water on Mars: ancient craters with fluidized ejecta, relatively more recent gullies inside those craters, and current abundance of near surface hydrogen around those craters. We find an association between gully occurrence and large-scale geologic features; analysis indicates unique depth/diameter ratios for gullied craters in Sirenum Terra. Numerical comparisons of fluidized and non-fluidized, gullied and non-gullied craters suggest that the Argyre region could have had a near-surface water table that receded before recent times, while Sirenum Terra may have had an ancient water table that persists to this day.

  16. Ancient Giant Basin/Aquifer System in the Arabia Region, Mars, and Its Influence on the Evolution of the Highland-Lowland Boundary

    NASA Technical Reports Server (NTRS)

    Dohm, J. M.; Barlow, N. G.; Williams, Jean-Pierre; Ferris, J. C.; Miyamoto, H.; Baker, V. R.; Boynton, W. V.; Strom, R. G.; Rodriguez, Alexis; Fairen, Alberto G.

    2004-01-01

    Ancient geologic and hydrologic phenomena on Mars observed through the magnetic data provide windows to the ancient past through the younger Argyre and Hellas impacts, the northern plains basement and the rock materials that mantle the basement, and the Tharsis and Elysium magmatic complexes (recently referred to as superplumes). These signatures, coupled with highly degraded macrostructures (tectonic features that energetic planet during its embryonic development (0.5 Ga or so of activity) with an active dynamo and magnetosphere. One such window into the ancient past occurs northwest of the Hellas impact basin in Arabia Tern. Arabia Terra is one of the few water-rich equatorial regions of Mars, as indicated I through impact crater and elemental information. This region records many unique characteristics, including predominately Noachian materials, a highland-lowland boundary region that is distinct from other boundary regions, the presence of very few macrostructures when compared to the rest of the cratered highlands, the largest region of fretted terrain on Mars, outflow channels such as Mamers Valles that do not have obvious origins, and distinct albedo, thermal inertia, gravity, magnetic, and elemental signatures.

  17. West Arabia Barchans

    NASA Technical Reports Server (NTRS)

    2005-01-01

    16 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows small barchan dunes on the floor of a crater in western Arabia Terra. Similar dunes are found in most of the larger craters of the region. The steepest slopes on these dunes, their slipfaces, point toward the west-southwest, indicating that dominant winds blow from the east-northeast (upper right).

    Location near: 10.9oN, 2.8oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  18. Arabia Bridal Veils

    NASA Technical Reports Server (NTRS)

    2006-01-01

    26 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of the stair-stepped, north wall of a crater in Arabia Terra. Light-toned slope streaks have formed as a result of avalanches in the dry, dark dust that mantles both the crater and its adjacent terrain in this scene.

    Location near: 20.0oN, 324.1oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  19. Possible Volcanic Province in Western Promethei Terra, Mars

    NASA Astrophysics Data System (ADS)

    Raitala, J.; Ivanov, M.; Kostama, V.; Korteniemi, J.; Törmänen, T.; Neukum, G.

    2007-12-01

    The western Promethei Terra region (36-50°S, 90-106°E) studied is roughly ~700 km across. It occupies a unique area on the smoothened eastern Hellas basin rim, and consists of two parts: a gentler (~0.07°, eastward of ~97°E) and a steeper (~0.88°, W of ~97°E) regional slope. The Noachian cratered terrain surrounds the region in the NE, E, and S. The large canyons of Harmakhis, Reull and Teviot Valles cut through the central area and the smooth Hesperian plains [1-10] of the western and central areas display a set of features that does not occur elsewhere on the eastern side of the Hellas basin. The plains have multi-layered interiors as seen on the walls of the canyons that cut them. Similar stacks of sub- horizontal layers are seen in other Martian regions with exposed lava plain interiors, for example, in Lunae Planum and Syrtis Major. These are classic volcanic provinces the layered structure of which was formed by successive emplacement of sheet lava flows that followed the general topographic trend. The average visible thickness of the Promethei layers is ~70-80 m and the typical measured canyon wall slope is ~25-30o. This gives an estimate of the thickness of the layers, which is ~35-45 m. The full layer stack thickness, estimated from observations, is ~1.3 km. Consistent with the observed layering, there are narrow wrinkle ridges (WR) that deform the surface of the plains. WR mostly occur in the eastern portion of the area near Reull and Teviot Valles but some of them are seen near Harmakhis Vallis in the west. Additional long straight narrow ridges (widths < km, heights 10s m, lengths 10s km), which occur in mostly NE-SW-oriented groups, are seen on the surface of the plains. The regional topography does not appear to control the distribution of the ridges. Their morphologic characteristics, areal distribution, and close association with the lava plains are consistent with and suggest that the straight ridges may represent exhumed dikes [11], which

  20. Extension across Tempe Terra, Mars, from measurements of fault scarp widths and deformed craters

    USGS Publications Warehouse

    Golombek, M.P.; Tanaka, K.L.; Franklin, B.J.

    1996-01-01

    Two independent methods, with no common assumptions, have been used to estimate the extension across the heavily deformed Tempe Terra province of the Tharsis region of Mars. One method uses measurements of normal fault scarp width with average scarp slope data for simple grabens and rifts on Mars to estimate the fault throw, which, combined with sparse fault dip data, can be used to estimate extension. Formal uncertainties in this method are only slightly greater than those in other methods, given that the total uncertainty is dominated by the likely uncertainty in the fault dip (assumed to be 60????15??). Measurement of normal fault scarp widths along two N25??-50??W directed traverses across Tempe Terra both yield about 22??16 km of extension (or ???2% strain across the northern traverse and nearly 3% across the southern one). About three quarters of the extension has occurred during the two main phases of Tharsis-related deformation from Middle/Late Noachian to Early Hesperian and from Late Hesperian to Early Amazonian, with more extension closer to the center of Tharsis during the first phase. Extension across the region was also determined by measuring the elongation and elongation direction of all ancient Noachian impact craters without ejecta blankets, which predate most of the deformation. Results have been corrected for initial non circularity of craters, established from similar measurements of young (post deformation) impact craters, yielding a statistically significant mean strain of 1.96??0.35% in a N38????10??W direction across Tempe Terra (extension of ???20??4, comparable in magnitude and direction to the average result from the scarp measurement method). Both methods indicate an average extension for single normal fault scarps (and shortening across wrinkle ridges for the crater method) of ???100 m. The agreement between the results of the two independent methods in overall extension and average single normal fault extension argues that the average

  1. Sedimentary deposits in Xanthe Terra: Implications for the ancient climate on Mars

    NASA Astrophysics Data System (ADS)

    Hauber, E.; Gwinner, K.; Kleinhans, M.; Reiss, D.; Di Achille, G.; Ori, G.-G.; Scholten, F.; Marinangeli, L.; Jaumann, R.; Neukum, G.

    2009-07-01

    A variety of sedimentary deposits is observed in Xanthe Terra, Mars, including Gilbert-type deltas, fan deltas dominated by resedimentation processes, and alluvial fans. Sediments were provided through deeply incised valleys, which were probably incised by both runoff and groundwater sapping. Mass balances based on High-Resolution Stereo Camera (HRSC) digital terrain models show that up to ˜30% of the material that was eroded in the valleys is present as deltas or alluvial fan deposits. Stratigraphic relationships and crater counts indicate an age of ˜4.0 to ˜3.8 Ga for the fluvial activity. Hydrologic modeling indicates that the deposits were probably formed in geologically very short time scales. Our results point to episodes of a warmer and wetter climate on early Mars, followed by a long period of significantly reduced erosion rates.

  2. Columbus crater and other possible groundwater-fed paleolakes of Terra Sirenum, Mars

    USGS Publications Warehouse

    Wray, J.J.; Milliken, R.E.; Dundas, C.M.; Swayze, G.A.; Andrews-Hanna, J. C.; Baldridge, A.M.; Chojnacki, M.; Bishop, J.L.; Ehlmann, B.L.; Murchie, S.L.; Clark, R.N.; Seelos, F.P.; Tornabene, L.L.; Squyres, S. W.

    2011-01-01

    Columbus crater in the Terra Sirenum region of the Martian southern highlands contains light-toned layered deposits with interbedded sulfate and phyllosilicate minerals, a rare occurrence on Mars. Here we investigate in detail the morphology, thermophysical properties, mineralogy, and stratigraphy of these deposits; explore their regional context; and interpret the crater's aqueous history. Hydrated mineral-bearing deposits occupy a discrete ring around the walls of Columbus crater and are also exposed beneath younger materials, possibly lava flows, on its floor. Widespread minerals identified in the crater include gypsum, polyhydrated and monohydrated Mg/Fe-sulfates, and kaolinite; localized deposits consistent with montmorillonite, Fe/Mg-phyllosilicates, jarosite, alunite, and crystalline ferric oxide or hydroxide are also detected. Thermal emission spectra suggest abundances of these minerals in the tens of percent range. Other craters in northwest Terra Sirenum also contain layered deposits and Al/Fe/Mg-phyllosilicates, but sulfates have so far been found only in Columbus and Cross craters. The region's intercrater plains contain scattered exposures of Al-phyllosilicates and one isolated mound with opaline silica, in addition to more common Fe/Mg-phyllosilicates with chlorides. A Late Noachian age is estimated for the aqueous deposits in Columbus, coinciding with a period of inferred groundwater upwelling and evaporation, which (according to model results reported here) could have formed evaporites in Columbus and other craters in Terra Sirenum. Hypotheses for the origin of these deposits include groundwater cementation of crater-filling sediments and/or direct precipitation from subaerial springs or in a deep (???900 m) paleolake. Especially under the deep lake scenario, which we prefer, chemical gradients in Columbus crater may have created a habitable environment at this location on early Mars. ?? 2011 by the American Geophysical Union.

  3. Columbus crater and other possible groundwater-fed paleolakes of Terra Sirenum, Mars

    NASA Astrophysics Data System (ADS)

    Wray, J. J.; Milliken, R. E.; Dundas, C. M.; Swayze, G. A.; Andrews-Hanna, J. C.; Baldridge, A. M.; Chojnacki, M.; Bishop, J. L.; Ehlmann, B. L.; Murchie, S. L.; Clark, R. N.; Seelos, F. P.; Tornabene, L. L.; Squyres, S. W.

    2011-01-01

    Columbus crater in the Terra Sirenum region of the Martian southern highlands contains light-toned layered deposits with interbedded sulfate and phyllosilicate minerals, a rare occurrence on Mars. Here we investigate in detail the morphology, thermophysical properties, mineralogy, and stratigraphy of these deposits; explore their regional context; and interpret the crater's aqueous history. Hydrated mineral-bearing deposits occupy a discrete ring around the walls of Columbus crater and are also exposed beneath younger materials, possibly lava flows, on its floor. Widespread minerals identified in the crater include gypsum, polyhydrated and monohydrated Mg/Fe-sulfates, and kaolinite; localized deposits consistent with montmorillonite, Fe/Mg-phyllosilicates, jarosite, alunite, and crystalline ferric oxide or hydroxide are also detected. Thermal emission spectra suggest abundances of these minerals in the tens of percent range. Other craters in northwest Terra Sirenum also contain layered deposits and Al/Fe/Mg-phyllosilicates, but sulfates have so far been found only in Columbus and Cross craters. The region's intercrater plains contain scattered exposures of Al-phyllosilicates and one isolated mound with opaline silica, in addition to more common Fe/Mg-phyllosilicates with chlorides. A Late Noachian age is estimated for the aqueous deposits in Columbus, coinciding with a period of inferred groundwater upwelling and evaporation, which (according to model results reported here) could have formed evaporites in Columbus and other craters in Terra Sirenum. Hypotheses for the origin of these deposits include groundwater cementation of crater-filling sediments and/or direct precipitation from subaerial springs or in a deep (˜900 m) paleolake. Especially under the deep lake scenario, which we prefer, chemical gradients in Columbus crater may have created a habitable environment at this location on early Mars.

  4. Characterization of hydrated silicate-bearing outcrops in Tyrrhena Terra, Mars: Implications to the alteration history of Mars

    NASA Astrophysics Data System (ADS)

    Loizeau, D.; Carter, J.; Bouley, S.; Mangold, N.; Poulet, F.; Bibring, J.-P.; Costard, F.; Langevin, Y.; Gondet, B.; Murchie, S. L.

    2012-05-01

    The Tyrrhena Terra region of Mars is studied with the imaging spectrometers OMEGA (Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité) onboard Mars Express and CRISM (Compact Reconnaissance Infrared Spectrometer for Mars) onboard Mars Reconnaissance Orbiter, through the observation of tens of craters that impacted into this part of the martian highlands. The 175 detections of hydrated silicates are reported, mainly associated with ejecta blankets, crater walls and rims, and central up-lifts. Sizes of craters where hydrated silicates are detected are highly variable, diameters range from less than 1 km to 42 km. We report the presence of zeolites and phyllosilicates like prehnite, Mg-chlorite, Mg-rich smectites and mixed-layer chlorites-smectites and chlorite-vermiculite from comparison of hyperspectral infrared observations with laboratory spectra. These minerals are associated with fresh craters post-dating any aqueous activity. They likely represent ancient hydrated terrains excavated by the crater-forming impacts, and hence reveal the composition of the altered Noachian crust, although crater-related hydrothermal activity may have played a minor role for the largest craters (>20 km in diameter). Most detected minerals formed over relatively high temperatures (100-300 °C), likely due to aqueous alteration of the Noachian crust by regional low grade metamorphism from the Noachian thermal gradient and/or by extended hydrothermal systems associated with Noachian volcanism and ancient large impact craters. This is in contrast with some other phyllosilicate-bearing regions like Mawrth Vallis where smectites, kaolinites and hydrated silica were mainly identified, pointing to a predominance of surface/shallow sub-surface alteration; and where excavation by impacts played only a minor role. Smooth plains containing hydrated silicates are observed at the boundary between the Noachian altered crust, dissected by fluvial valleys, and the Hesperian

  5. Evidence for Recent Liquid Water on Mars: Gullies in Crater Wall, Noachis Terra

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    Gullies eroded into the wall of a meteor impact crater in Noachis Terra. This high resolution view (top left) from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) shows channels and associated aprons of debris that are interpreted to have formed by groundwater seepage, surface runoff, and debris flow. The lack of small craters superimposed on the channels and apron deposits indicates that these features are geologically young. It is possible that these gullies indicate that liquid water is present within the martian subsurface today.

    The MOC image was acquired on September 28, 1999. The scene covers an area approximately 3 kilometers (1.9 miles) wide by 6.7 km (4.1 mi) high (note, the aspect ratio is 1.5 to 1.0). Sunlight illuminates this area from the upper left. The image is located near 54.8oS, 342.5oW. The context image (above) shows the location of the MOC image on the south-facing wall of an impact crater approximately 20 kilometers (12 miles) in diameter. The context picture was obtained by the Viking 1 orbiter in 1980 and is illuminated from the upper left. The large mound on the floor of the crater in the context view is a sand dune field. The Mars Orbiter Camera high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s.

    A brief description of how the color was generated: The MOC narrow angle camera only takes grayscale (black and white) pictures. To create the color versions seen here, we have taken much lower resolution red and blue images acquired by the MOC's wide angle cameras, and by the Viking Orbiter cameras in the 1970s, synthesized a green image by averaging red and blue, and created a pallette of colors that represent the range of colors on Mars. We then use a relationship that correlates color and brightness to assign a color to

  6. Geologic Map of MTM -20012 and -25012 Quadrangles, Margaritifer Terra Region of Mars

    USGS Publications Warehouse

    Grant, J. A.; Wilson, S.A.; Fortezzo, C.M.; Clark, D.A.

    2009-01-01

    Mars Transverse Mercator (MTM) -20012 and -25012 quadrangles (lat 17.5 deg - 27.5 deg S., long 345 deg - 350 deg E.) cover a portion of Margaritifer Terra near the east end of Valles Marineris. The map area consists of a diverse assemblage of geologic surfaces including isolated knobs of rugged mountainous material, heavily cratered and dissected ancient highland material, a variety of plains materials, chaotic terrain materials, and one of the highest densities of preserved valleys and their associated deposits on the planet (Saunders, 1979; Baker, 1982; Phillips and others, 2000, 2001). The map area is centered on a degraded, partially filled, ~200-km-diameter impact structure (lat 22 deg S., long 347.5 deg E.), informally referred to as Parana basin, located between Parana Valles to the east and Loire Valles to the west. Parana Valles is a network of multidigitate, mostly east-west-oriented valleys that flowed west and discharged into Parana basin (Grant, 1987, 2000; Grant and Parker, 2002). Loire Valles, broadly comparable in length to the Grand Canyon on Earth, has a deeply incised channel within the map area that originates at the west-northwest edge of Erythraeum Chaos within Parana basin (Grant, 1987, 2000; Grant and Parker, 2002; Strom and others, 2000). Parana and Loire Valles, combined with Samara Valles to the west, form one of the most laterally extensive, well-integrated valley networks on Mars (Grant, 2000) and record a long history of modification by fluvial processes. The origin and morphology of the valley networks, therefore, provide insight into past environmental conditions, whereas their relation with other landforms helps constrain the timing and role of fluvial processes in the evolution and modification of the Margaritifer Terra region.

  7. Sedimentary deposits in Xanthe Terra: Implications for the ancient climate on Mars

    NASA Astrophysics Data System (ADS)

    Hauber, E.; Gwinner, K.; Kleinhans, M.; Reiss, D.; di Achille, G.; Ori, G.-G.; Scholten, F.; Marinangeli, L.; Jaumann, R.; Neukum, G.

    2008-09-01

    Summary A variety of sedimentary deposits is observed in Xanthe Terra, Mars, including Gilbert-type deltas, fan deltas dominated by resedimentation processes, and alluvial fans. Sediments were provided through deeply incised valleys, which were probably incised by both runoff and groundwater sapping. Mass balances based on high-resolution HRSC digital terrain models show that up to ~30% of the material that was eroded in the valleys is present as deltas or alluvial fan deposits. Stratigraphic relationships and crater counts indicate an age of ~4.0 to ~3.8 Ga for the fluvial activity. Hydrologic modeling indicates that the deposits were probably formed in geologically very short time-scales. Our results indicate episodes of a warmer and wetter climate on early Mars, followed by a long period of significantly reduced erosion rates. Background Fluvial and lacustrine deposits on Mars contain a record of past hydrological conditions and are important targets of environmental and paleoclimatic studies. Ancient depositional landforms associated with fluvial channels are generally thought to indicate an active hydrosphere, involving precipitation, runoff, and significant erosion. However, the exact nature of the flow processes and the time-scales over which they occurred are under debate. End-member scenarios are represented by an early Mars that was either wet and warm or cold and dry. The analysis of sedimentary deposits can constrain paleohydrological models. For example, a warmer climate and persistent flow would have been required if they were formed in long-standing paleolakes. Alternatively, fans and deltas might have formed under subaerial conditions or in short-lived lakes. Therefore, the determination of the time when such deposits were formed in Mars` history, the duration of the fluvial activity, and the type of sedimentary environment is a critical component of paleoclimatic studies of Mars. Data The High Resolution Stereo Camera (HRSC) on the Mars Express

  8. Analysis of crater valleys, Noachis Terra, Mars: Evidence of fluvial and glacial processes

    NASA Astrophysics Data System (ADS)

    Hobbs, S. W.; Clarke, J. D. A.; Paull, D. J.

    2016-05-01

    The precise mechanism for the formation and evolution of crater valley networks in the Martian southern highlands remains under debate, with precipitation, groundwater flow, and melting induced by impact being suggested. We studied valley networks within four craters of the Noachis Terra highlands that were representative of similar features in Noachis Terra and where orbital data existed for analysis in order to characterise their morphology and infer possible processes involved in their formation and evolution. We found evidence for valleys carved by liquid water and ice-related processes. This included strong evidence of liquid water-based valley formation through melting of ice-rich deposits throughout our study area, suggesting an alternative to previously suggested rainfall or groundwater-based scenarios. The location of these valleys on steeply sloping crater walls, as opposed to the shallow slopes of the highlands where Martian valleys are typically found, suggested that our 'fluvial' valleys had not evolved a more structured fluvial morphology as valley networks found on the Martian plains. Our studied valleys' association with ice-rich material and abundant evidence for erosion caused by downslope flow of ice-rich material are consistent with a cold, wet Mars hypothesis where accumulation, flow, and melting of ice have been dominant factors in eroding crater valleys. Additionally, analysis of valley morphology with slope and aspect suggested a greater dependence on local geology and presence of volatiles than larger valley networks, though ice-related valleys were consistently wider for their length than valleys assessed as fluvial carved. We assessed that local conditions such as climate, geology, and availability of ice-rich material played a major role in the erosion of crater valleys at our study site.

  9. Detailed spectroscopic analysis of chloride salt deposits in Terra Sirenum, Mars

    NASA Astrophysics Data System (ADS)

    Osterloo, M. M.; Glotch, T. D.; Bandfield, J. L.

    2015-12-01

    Chloride salt-bearing deposits have been identified throughout the southern highlands of Mars [1] based on the lack of diagnostic spectral features of anhydrous chlorides in both the visible near infrared (VNIR) and middle infrared (MIR) wavelength ranges [1,2]. A puzzling aspect of martian chloride deposits is the apparent lack of other weathering or evaporite phases associated with most of the deposits. A global analysis over the chloride salt sites conducted by [3] found that only ~9% of the deposits they analyzed were associated with minerals such as phyllosilicates. Most of these occurrences are in Terra Sirenum where [4] noted that salt-bearing deposits lie stratigraphically above Noachian phyllosilicates. Although a variety of formation mechanisms have been proposed for these intriguing deposits, detailed geologic mapping by [5] suggests that surface water and evaporation played a dominant role. On Earth, evaporative settings are often characterized by a multitude of evaporite and phyllosilicate phases including carbonates, sulfates, and nitrates. [6] evaluated chemical divides and brine evolution for martian systems and their results indicate three pathways wherein late-stage brines favor chloride precipitation. In each case the pathway to chloride formation includes precipitation of carbonates (calcite, siderite, and/or magnesite) and sulfates (gypsum, melanterite, and/or epsomite). Here, we present the results of our detailed and systematic spectroscopic study to identify additional evaporite phases associated with salt/silicate mixtures in Terra Sirenum. [1] Osterloo et al. (2008) Science, 319, [2] Glotch, T. D. et al. (2013) Lunar and Planet. Sci. XLIV, abstract #1549 [3] Ruesch, O. et al. (2012), J. Geophys. Res., 117, E00J13 [4] Glotch, T. D. et al. (2010) Geophys. Res. Lett. 37, L16202, [5] Osterloo, M. M. and B. M Hynek (2015) Lunar and Planet. Sci XLVI. Abstract #1054 [6] Tosca, N. J. and S. M. McLennan (2006), Earth and Planet. Sci. Lett., 241.

  10. Possible crater-based karstic and lacustrine terrain in Tyrrhena Terra, Mars.

    NASA Astrophysics Data System (ADS)

    Baioni, Davide; Soare, Richard

    2015-04-01

    We have identified two craters in Tyrrhena Terra, Mars (19.560 S, 67.480 E, 18.500 S, 68.340 E), where crater-floor deposits display traits that are consistent with formation by karst-driven processes. Tyrrhena Terra is located in the cratered highlands of the southern Martian hemisphere, immediately to the northeast of Hellas Planitia and to the southeast of Isidis Planitia. Crater diameters in the region vary widely, from metres to 100km. Most of these craters are moderately to highly degraded and many show bright deposits on their floors. Here, we present some of the key characteristics associated with these bright deposits and explain why a "karstic" formation hypothesis is reasonable. First and foremost amongst these characteristics are depressions that are ubiquitous within the bright deposits. They display a variety of plan forms ranging from rounded, circular, elongated, polygonal and drop-like to elliptical. Moreover, they display strong morphometric (sizes) and morphologic (shapes, bottoms, walls) similarities with the karst depressions that are common on limestone and evaporite terrains on the Earth. Some depression morphologies - rounded/elongate - could be the result of formation by coalescence. We infer that the depressions are dolines, karstic features formed polygenetically by corrosion and solution-related intra-crater processes; we also demonstrate why the formation of the depressions by aeolian, periglacial, volcanic or impact-related processes seems less plausible by karst-related ones. Interestingly, polygonal cracks whose morphology points to an origin by dessication often cross-cut the bright deposits; as such, their crater floor presence could be an important co-marker of ponded or running liquid water within the craters where they are observed.

  11. Analysis of Ice-Related Intra-Crater Facies in Promethei Terra, Mars

    NASA Astrophysics Data System (ADS)

    Orgel, Csilla; Kereszturi, Ákos; van Gasselt, Stephan

    2014-05-01

    On Mars ice-related landforms have been identified at mid-latitudes between 30° and 50° in both hemispheres including the areas of Tempe Terra, Deuteronilus-Protonilus Mensae, Phlegra Montes and the rims of the southern-hemispheric impact basins Argyre and Hellas [1-7]. Our study area - informally termed hourglass-shaped crater [8] - is located near Reull Vallis on the eastern rim of the Hellas impact basin (39.0°S, 102.8°E). Impact-crater infill was described as debris-covered piedmont-type glacier [8] based on analysis of High Resolution Stereo Camera (HRSC) data, and implies a glacial origin with precipitation of ice during higher obliquity phases. Recent, higher-resolution image data such as data of the High Resolution Imaging Science Experiment (HiRISE) and the Context Imager (CTX) provide a more detailed picture of the lateral distribution of different small-scale surface features indicative of periglacial and/or glacial origin. The aim of this study is to identify qualitative and quantitative characteristics of these ice-related landforms and to separate sources of water ice and related processes. Initial age determinations based on impact-crater size-frequency statistics indicate an age of 3.4 Gyr for the impact-crater and an age of approximately 75 Myr for the infill [8]. In order to identify a possible sequence of surface-feature evolution we calculated the age distribution of four major surface units which span ages ages between 1-47 Myr. Along with detailed age information and a separation of different processes at this confined type location of Mars young-Amazonian landscape evolution and potential cyclic signals are being reconstructed to constrain climate evolution. Carr, M. H. & Schaber, G. G. 1977: Martian permafrost features.- J. Geophys. Res. 82, 4039-4054. Squyres, S. W. 1978: Martian fretted terrain: flow of erosional debris.- Icarus 34, 600-613. Squyres, S. W. 1979: The distribution of lobate debris aprons and similar flows on Mars.- J

  12. New Mineralogic Diversity in the Noachian Crust of Tyrrhena Terra, Mars

    NASA Astrophysics Data System (ADS)

    Seelos, K. D.; Seelos, F. P., IV; Viviano-Beck, C.; Murchie, S. L.

    2015-12-01

    The cratered Noachian highlands region of Mars is host to hundreds to thousands of exposures of hydrated minerals. Areas of the highlands that are relatively free of dust, such as Tyrrhena Terra, have been previously examined using Mars Express/OMEGA and MRO/CRISM visible/near-IR reflectance data. The inferred alteration mineralogy is consistent with formation under low water to rock ratio, relatively low T/P and shallow crustal conditions. The vast majority of occurrences are associated with impact craters with a wide range of diameters, and within not only central peaks, but also rims and ejecta. This implies that most outcrops are a result of the excavation of pre-existing mineralology, not formation in-situ by post-impact hydrothermalism. Types of minerals reported include, most commonly, Fe/Mg phyllosilicates (smectite, chlorite, mixed-layer clays, prehnite, serpentine, illite), and less commonly, Al-phyllosilicates (e.g., kaolinite), carbonates, zeolites (e.g., analcime), and hydrated silica. Here we document and characterize the occurrence of an additional class of mineralogy in Noachian terrain: hydrated sulfates. Hydrated sulfates are observed in the central peaks and (in one case) the proximal ejecta of 3 craters dispersed across the region. In each crater, a diverse assemblage of other hydrated alteration minerals is also apparent and includes prehnite, carbonate, zeolite, Fe/Mg smectite, and chlorite. Two of the three craters are approximately 10 km in diameter, with resulting sulfate exhumation depths in the central peaks approaching 1 km. The third crater has a diameter of 25 km; however, uplift and ejecta from several pre-existing impacts reduce the possible sulfate excavation depth to 1.3 km. CRISM spectra are consistent with a poly-hydrated sulfate, with major absorptions centered at 1.45, 1.95, and 2.4 micrometers - similar to, but distinct from, many zeolites. While mono-hydrated and poly-hydrated sulfates are not uncommon to other areas of Mars

  13. Exploration Zone for Human Mission to Mars: The Area South of Firsoff Crater in Arabia Terra

    NASA Astrophysics Data System (ADS)

    Ori, G. G.; Pondrelli, M.

    2015-10-01

    We are proposing an area south of Firsoff Crater that scientifically includes: reconstruction of the stratigraphy at global scale, the identification of sedimentary environment and paleoclimatic conditions and large astrobiological potentiality.

  14. Sediments of Arabia

    NASA Technical Reports Server (NTRS)

    2005-01-01

    21 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows martian sediment in two basic forms: (1) light-toned, layered, sedimentary rock outcrops and (2) dark, windblown sand dunes. The dark sand of the dunes is most likely composed of grains rich in iron-, magnesium-, aluminum-, and silicon-bearing minerals. The hills and mounds of layered sedimentary rock were once more extensive, covering the entire scene shown here, which occurs on the floor of a crater in western Arabia Terra.

    Location near: 8.9oN, 1.2oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  15. Detection and context of hydrated mineralogy in the Tyrrhena Terra region, Mars

    NASA Astrophysics Data System (ADS)

    den Haan, J.; Zegers, T. E.; van Ruitenbeek, F. J. A.; van der Werff, H. M. A.; Rossi, A.

    2008-09-01

    Introduction The discovery of phyllosilicates on Mars [1] has had major implications on the perceived geologic and climatologic evolution of Mars [2]. Not only do phyllosilicates represent a `wet' period on Mars, they might also represent a potentially favorable environment for life. The phyllosilicates have so far exclusively been found in or close to ancient Noachian highland terrain. Those phyllosilicate deposits studied (e.g. [3]) show a clear association between hydrated mineralogy and heavily eroded and crater-saturated outcrops. Phyllosilicates on Earth are associated with a wide variety of geological processes (volcanism, metamorphism, hydrothermal alteration, sedimentation). The occurrence of phyllosilicates on Mars may be equally diverse in nature. To be able to place constraints on the early Martian environment, the processes by which these phyllosilicates formed need to be reconstructed. To derive this information from individual phyllosilicate deposits, it is necessary to interpret their composition in relation to their geological context and relative time relationships. We conducted such an integrated hyperspectral and geological study of the Tyrrhena Terra region. Data products ad methods HRSC data products (both image at 12 m/pixel and stereo-derived DTMs) are used for examining geologic cross-cutting relationships, geomorphologic landforms and visual determination of unit boundaries. Odyssey THEMIS nighttime TIR images are analyzed for spatial variations in thermal inertia. Where available, HRSC is supplemented by higher-resolution visible observations of CTX or MOC. Hyperspectral analysis is conducted using data from the OMEGA hyperspectral instrument. In order to batch-process large amounts of OMEGA data, an IDL/ENVI tool was developed on top of the existing SOFT04, distributed by PSA. The applied atmospheric correction assumes that atmospheric contributions are multiplicative, and follow a power-law distribution with altitude [4]. The ratio of

  16. Comparison of Plains Volcanism in the Tempe Terra Region of Mars to the Eastern Snake River Plains, Idaho with Implications for Geochemical Constraints

    NASA Technical Reports Server (NTRS)

    Weren, S. L.; Sakimoto, S. E. H.; Hughes, S. S.; Gregg, T. K. P.

    2004-01-01

    The Eastern Snake River Plains (ESRP) in Idaho have long been considered a terrestrial analog for the plains volcanism like that evident in Syria Planum and Tempe Terra, Mars. Both the ESRP and Tempe Terra are sediment-blanketed volcanic fields in areas with significant extensional faulting. Similar volcanic features can be observed throughout both study areas using field analysis and DEMs of the ESRP and the Mars Global Surveyor (MGS) data from Mars. These features include flow fields, low shields, shields with steep summits, and fissure eruptions. A few other volcanic features, such as cinder cones, which suggest variable compositions, volatile interactions, and multiple volcanic events can be seen in both areas. The eruptions in both the ESRP and Tempe Terra generally originate from the fissures creating elongate, multi-vent shields as well as isolated or aligned single vent shields. Many of these show evidence of radial flow patterns from summit craters as well as lava tube fed flows. The volcanoes of Tempe Terra display some of the global latitudinal parameter trends of small volcanoes on Mars. Some of these trends may be explained by the variation of volatile content and compositional variation across Mars. However, within Tempe Terra no significant local latitudinal trends can be seen in edifice attributes and not all variations are explained by global trends. This study builds upon previous studies of the Tempe Terra region and the ESRP in order to develop a more detailed representation of features and topographic data. Using these data we attempt to help constrain the composition and eruptive style of the Tempe Terra volcanoes by correlating them with the similar and quantified ESRP variations.

  17. THEMIS and MOLA Provide 3-D Stratigraphy in the Terra Meridiani Region of Mars

    NASA Astrophysics Data System (ADS)

    Phillips, R. J.; Hynek, B. M.

    2005-12-01

    The layered rocks observed in the vicinity of the Mars Exploration Rover (MER) Opportunity landing site are part of a vast stratigraphic complex exposed over ~3×105km2, encompassing 20° of longitude [Hynek, 2004, Nature]. We have used elevations derived from geoid- and orbit-corrected individual MOLA laser shots to determine the three-dimensional disposition of individual stratigraphic horizons exposed within the complex and as mapped with 100 m/pix THEMIS thermal inertia images (high inertia areas correspond to ``etched terrain''). The Opportunity landing site is near the NW edge of an elongated NE-trending topographic bench that contains the hematite-rich plains unit and is about 500 km wide. Mappable stratigraphic exposures occur mostly in two groups, one near the base of the upward slope (to the Arabia Highlands) on the SE side of the bench and one near the top of the downward slope (to the Northern Lowlands) on the NW side of the bench. The total thickness of the stratigraphic complex is ~1000 m. We fit least-squares planes to individual horizons and tested for quality of fit. Our main interest is the orientations of the planes, so the probability density function of the tangent of the dip azimuth was used as a discriminator for solution acceptance (dip azimuth error range < 30°). Of the 22 horizons sampled, 14 had acceptable solutions. The 14 individual stratigraphic horizons are spatially extensive, with maximum MOLA sampling separations in a given horizon being as much as 200 km (mean for all horizons is 80 km). This implies that the depositional environment for these units was coherent over a scale of typically 100 km. Of the 14 acceptable horizons, 10 have shallow dip azimuths in the direction N to NW, consistent with the long-wavelength (regional) slope, which itself is the result of the global pole-to-pole slope plus Noachian-aged Tharsis-induced membrane deformation [Phillips et al., 2001, Science]. The stratigraphic complex both overlies and is

  18. Evaluation of Surface Slope Effects on Ripple Orientations Observed on Sand Dunes in the Terra Tyrrhena Region of Mars

    NASA Astrophysics Data System (ADS)

    Zimbelman, J. R.; Johnson, M. B.

    2014-12-01

    The High Resolution Imaging Science Experiment (HiRISE) has revealed abundant wind ripples on sand dunes across Mars. Ripple orientations have been documented using HiRISE images of sand dunes at 24 widely distributed sites across Mars, in order to identify the last significant wind directions at these locations. Howard (GSAB, 1977) gives a mathematical expression for how surface slopes on a sand dune can affect the orientation of ripples with respect to the formative winds. In order to evaluate this mechanism for measured ripple orientations on Mars, quantitative data for surface slopes on the sand dunes is required. Stereo pairs of HiRISE images are used to generate Digital Terrain Models (DTMs) with postings of one meter. In June 2014 we produced a DTM of sand dunes in the Terra Tyrrhena region of Mars (14.55° S, 97.77° E) using SOCET SET at the Astrogeology Branch, USGS-Flagstaff. Typically it is difficult for feature matching software to work well on sand dunes, but our stereo images (ESP_022609_1655 and ESP_026675_1655) were obtained only six Earth days apart under excellent illumination conditions. The Terra Tyrrhena DTM had remarkably few artifacts on the sand dunes (except at slip faces, where the average slope between slip face crest and base was interpolated) and excellent control from irregular terrain exposed in interdune areas. Slopes on the stoss sides of sand dunes are generally <10°; the Howard equation indicates ripple deflection angles should be <17° with respect to the actual surface wind direction. We are adjusting documented ripple orientations to account for surface slopes utilizing the DTM data, and so far we do not see major changes to inferred surface wind directions that would be derived directly from the ripple orientations.

  19. Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: Project Introduction and First Year Work Plan

    NASA Technical Reports Server (NTRS)

    Skiner, J. A., Jr.; Rogers, A. D.; Seelos, K. D.

    2009-01-01

    The highland-lowland boundary (HLB) of Mars is interpreted to be a complex tectonic and erosional transition that may hold evidence for past geologic processes and environments. The HLB-abutting margin of the Libya Montes and the interbasin plains of northern Tyrrhena Terra display an exceptional view of the earliest to middle history of Mars that has yet to be fully characterized. This region contains some of the oldest exposed materials on the Martian surface as well as aqueous mineral signatures that may be potential chemical artifacts of early highland formational processes. However, a full understanding of the regions geologic and stratigraphic evolution is remarkably lacking. Some outstanding questions regarding the geologic evolution of Libya Montes and northern Tyrrhena Terra in-clude: Does combining geomorphology and composition advance our understanding of the region s evolution? Can highland materials be subdivided into stratigraphically discrete rock and sediment sequences? What do major physiographic transitions imply about the balanced tectonism, climate change, and erosion? Where is the erosional origin and what is the post-depositional history of channel and plains units? When and in what types of environments did aqueous mineral signatures arise? This abstract introduces the geologic setting, science rationale, and first year work plan of a recently-funded 4-year geologic mapping proposal (project year = calendar year). The objective is to delineate the geologic evolution of Libya Montes and northern Tyrrhena Terra at 1:1M scale using both classical geomorphological and compositional mapping techniques. The funded quadrangles are MTMs 00282, -05282, -10282, 00277, -05277, and -10277.

  20. Multiple Episodes of Recent Gully Activity Indicated by Gully Fan Stratigraphy in Eastern Promethei Terra, Mars.

    NASA Astrophysics Data System (ADS)

    Schon, S.; Head, J.; Fassett, C.

    2008-09-01

    Introduction Gullies are considered among the youngest geomorphic features on Mars based upon their stratigraphic relationships, superposition on steep slopes and distinctive morphology in unconsolidated sediment. Multiple formation hypotheses have been proposed, which can be divided into three broad classes: entirely dry mechanisms (e.g., [1,2]), wet mechanisms invoking groundwater or ground ice (e.g., [3,4]) and wet mechanisms invoking surficial meltwater (e.g., [5,6,7,8]). It has been difficult to differentiate between these hypotheses based upon past observations and it remains possible that gullies are polygenetic landforms. This study presents stratigraphic relationships in the depositional fan of a crater wall gully system that suggest: (1) multiple episodes of alluvial fan-style deposition, (2) very recent depositional activity that is younger than a newly recognized rayed crater, and (3) surficial snowmelt as the most likely source of these multiple episodes of recent gully activity. Gully-Fan Stratigraphy In Eastern Promethei Terra an ~5 km-diameter crater is observed with a well-developed gully system (Fig. 1) and several smaller gullies in its northnortheast wall. The large gully system (composed of a small western gully and larger eastern gully) shows evidence for incision into the crater wall country rock and has multiple contributory sub-alcoves and channels. The depositional fan associated with this gully system is bounded on its western side by a small arcuate ridge swell that is not observed on the eastern side of the fan. This ridge is interpreted as a moraine-like structure that may have bounded a glacially-formed depression into which the fan is deposited [8]. Similar depressions with bounding ridges are commonly observed in this latitude band (~30-50°S) in association with deeply incised gully alcoves [9,10,11]. This gully fan is composed of multiple lobes with distinct lobe contacts, incised channels, and cut-andfill deposits - all features

  1. Fluvial channels in the north-western part of Noachis Terra, Mars: Implications for tectonic controls

    NASA Astrophysics Data System (ADS)

    De, K.; Dasgupta, N.; Kundu, A.; Chauhan, P.

    2015-10-01

    Palaeochannels in the western part of Noachis Terra are mapped to understand their origin and also the control on their courses. Relation to impact craters, trends and cross- correlations between their paths indicates to impact-related origin and tectonic lineament controlled courses for the rivers.

  2. Thermal Inertia, Albedo, and MOLA-derived Roughness for Terrains in the Terra Meridiani Area, Mars

    NASA Technical Reports Server (NTRS)

    Arvidson, R. E.; Deal, K.; Hynek, B. M.; Seelos, F. P., IV; Snider, N. O.; Mellon, M. T.; Garvin, J. B.

    2002-01-01

    Surface properties of layered deposits draped on dissected, cratered terrain in the Terra Meridiani area are analyzed using remote sensing data. The etched plains are cemented and differentially eroded, and the hematite plains are loose and drifting. Additional information is contained in the original extended abstract.

  3. Evidence for Noachian flood volcanism in Noachis Terra, Mars, and the possible role of Hellas impact basin tectonics

    NASA Astrophysics Data System (ADS)

    Rogers, A. D.; Nazarian, A. H.

    2013-05-01

    Spectral and imaging data sets from Mars Reconnaissance Orbiter and Mars Odyssey, as well as spectral and topographic data from Mars Global Surveyor, are used to understand the origin of in-place rock units found in the intercrater plains and Hellas circumferential graben floors of Noachis Terra, Mars. The rocky units are interpreted as effusive volcanic plains on the basis of broad areal extent, structural competence, association with topographic lows, distinct mineralogy from regolith, and lack of sedimentary textures or minerals associated with aqueous processes. Some rocky expanses contain at least two compositionally distinct units. The relatively light-toned unit exhibits a higher plagioclase/pyroxene ratio than the lower, dark-toned unit. Both units exhibit ~10% olivine enrichment compared to surrounding regolith. These units are heavily degraded and exhibit crater model ages between ~3.80 and 4.0 Ga, making these some of the oldest preserved volcanic plains accessible by remote sensing. They are found in association with Hellas ring structures, where the westward extent of these rocky units is limited to the outermost ring structure. Fracturing associated with the Hellas impact may have enabled magmas to ascend from the base of the crust in the circum-Hellas region. Identification of these units as volcanic materials extends previous estimates for volume of outgassed volatiles. Though the estimated volcanic volume increase is minor, the local effects could have been significant. The role of multi-ring impact basins in providing a spatial control on Martian highlands volcanism and subsurface mineralization may have been underestimated in the past.

  4. Geology of Holden Crater and the Holden and Ladon Multi-Ring Impact Basins, Margaritifer Terra, Mars

    NASA Technical Reports Server (NTRS)

    Irwin, R. P., III; Grant, J. A.

    2008-01-01

    Geologic mapping at 1:500K scale of Mars quads 15s027, 20s027, 25s027, and 25s032 (Fig. 1) is in progress to constrain the geologic and geomorphic history of southwestern Margaritifer Terra. This work builds on earlier maps at 1:5M [1] and 1:15M scales [2], recent to concurrent 1:500Kscale mapping of adjacent areas to the east [3-5], and studies of drainage basin evolution along the Uzboi-Ladon-M (ULM; the third valley in the sequence has no formal name) Valles basin overflow system and nearby watersheds [6-9]. Two of the six landing sites under consideration for the Mars Science Laboratory rover are in this map area, targeting finely layered, phyllosilicate-rich strata and alluvial fans in Holden crater [10-12] (26degS, 34degW, 150 km diameter) or deposits southeast of a likely delta in Eberswalde crater [13-16] (24degS, 33degW, 50 km in diameter). Diverse processes including larger and smaller impacts, a wide range in fluvial activity, and local to regional structural influences have all affected the surface morphology.

  5. Blueberries on Earth and Mars: Some Correlations Between Andean Paleosols, Geothermal Pipes in Navajo Sandstone and Terra Meridiani on Mars

    NASA Astrophysics Data System (ADS)

    Mahaney, W. C.; Milner, M. W.; Netoff, D. I.; Dohm, J. M.; Sodhi, R. N. S.; Aufreiter, S.; Hancock, R. G. V.; Bezada, M.; Kalm, V.; Malloch, D.

    2006-03-01

    The origin of "blueberries" on Mars and their relationship to similar concretionary forms on Earth invokes a process of variable redox conditions in underground fluids. The possible role of microorganisms in the origin of bluberries opens an avenue for biological investigations.

  6. Fluvial Degradation of the Highlands: The Terra Tyrrhena Region of Mars

    NASA Technical Reports Server (NTRS)

    Mest, S. C.; Crown, D. A.; Harbert, W.

    2002-01-01

    Geologic and geomorphic analyses of highland terrains reveal the effects of fluvial erosion by well-integrated valley networks. Hydrologic modeling using 128 pix/deg Mars Orbiting Laser Altimeter (MOLA) gridded topography is being done to quantitatively characterize these systems. Additional information is contained in the original extended abstract.

  7. Multi-agent gully processes: Evidence from the Monaro Volcanic Province, Australia and in Terra Cimmeria, Mars

    NASA Astrophysics Data System (ADS)

    Hobbs, S. W.; Paull, D. J.; Clarke, J. D. A.; Roach, Ian C.

    2016-03-01

    Comparison of the similarities and differences between terrestrial and Martian hillside gullies promotes understanding of how surface processes operate on both planets. Here we tested the viability of subsurface flow of water as a process affecting gully evolution. We compared gullies within the Monaro Volcanic Province near Cooma, New South Wales, Australia, to gullies possessing strong structural control near Gasa Crater, Terra Cimmeria, Mars. Although cursory examination of the Monaro gullies initially suggested strong evidence for aquifer erosion, detailed field surveys showed the evidence to be ambiguous. Instead a complex regime of erosion dependent on multiple conditions and processes such as local geology, surface runoff, dry mass wasting, and animal activity emerged. We found the morphology of gullies near Gasa Crater to be consistent with erosion caused by liquid water, while also being heavily influenced by the local environment, including slope and geology. Additionally, erosion at the Martian site was not consistent with evidence of subsequent, smaller scale erosion and channel modification by dry mass wasting. Local conditions thus play an important role in gully evolution, further highlighting that processes forming Martian gullies may be more diverse than initially thought.

  8. Hydrological evolution of Atlantis basin, Sirenum Terrae, Mars. Preliminar analysis of MOC and THEMIS images.

    NASA Astrophysics Data System (ADS)

    de Pablo, M. A.; Márquez, A.; Centeno, J. D.

    The Atlantis basin is one of the martian highlands areas where there was proposed the existence of an ancient lake during the early geological history of Mars [1] [2] [3] [4]. The existence of some morphological features inside the basin and in the surrounding area, allow to check the existence of liquid water in the past of the planet. On the other hand, other morphological features indicate the existence of snow and liquid groundwater in recent times. The detailed study of the geomorphologic features allows to make an approach to the hydrological evolution of the Atlantis basin. The study of the geomorphology of this region has been carried out by means of the analysis of MOC high resolution images obtained by the Mars Global Surveyor mission and the THEMIS images, in the visible spectrum, sent by Mars Odyssey spacecrafts. The most clearly morphological feature indicative of the existence of water in the surface of Mars in the past are the numerous channels that end into Atlantis basin from the highest terrains. In addiction to these fluvial channels, the existence of mass flow deposits is also indicative of the existence of water in the area. Some of these slumps are in the internal slopes of impact craters, but others cover huge extensions around the chaotic terrains of the studied area. The lobated ejecta deposits observed in the Atlantis basin region are indicative of the existence of groundwater (solid or liquid) [5]. Serrated reliefs and tables in the borders of the basins are indicative of the existence of a water sheet. Beneath this water sheet some deposits was formed which was eroded, due to the gradual desiccation of the basin, forming the tables and serrated reliefs. The existence of different chaotic terrains in the area implies the existence of huge amounts of water under the surface according to the different models of chaotic terrain formation [6] [7]. The existence of groundwater could be decided by the existence of collapses in the near to the

  9. Hydrological evolution of Atlantis basin, Sirenum Terrae, Mars. Preliminar analysis of MOC and THEMIS images.

    NASA Astrophysics Data System (ADS)

    de Pablo, M. A.; Márquez, A.; Centeno, J. D.

    The Atlantis basin is one of the martian highlands areas where there was proposed the existence of an ancient lake during the early geological history of Mars [1] [2] [3] [4]. The existence of some morphological features inside the basin and in the surrounding area, allow to check the existence of liquid water in the past of the planet. On the other hand, other morphological features indicate the existence of snow and liquid groundwater in recent times. The detailed study of the geomorphologic features allows to make an approach to the hydrological evolution of the Atlantis basin. The study of the geomorphology of this region has been carried out by means of the analysis of MOC high resolution images obtained by the Mars Global Surveyor mission and the THEMIS images, in the visible spectrum, sent by Mars Odyssey spacecrafts. The most clearly morphological feature indicative of the existence of water in the surface of Mars in the past are the numerous channels that end into Atlantis basin from the highest terrains. In addiction to these fluvial channels, the existence of mass flow deposits is also indicative of the existence of water in the area. Some of these slumps are in the internal slopes of impact craters, but others cover huge extensions around the chaotic terrains of the studied area. The lobated ejecta deposits observed in the Atlantis basin region are indicative of the existence of groundwater (solid or liquid) [5]. Serrated reliefs and tables in the borders of the basins are indicative of the existence of a water sheet. Beneath this water sheet some deposits was formed which was eroded, due to the gradual desiccation of the basin, forming the tables and serrated reliefs. The existence of different chaotic terrains in the area implies the existence of huge amounts of water under the surface according to the different models of chaotic terrain formation [6] [7]. The existence of groundwater could be decided by the existence of collapses in the near to the

  10. Analysis of regional gullies within Noachis Terra, Mars: A complex relationship between slope, surface material and aspect

    NASA Astrophysics Data System (ADS)

    Hobbs, S. W.; Paull, D. J.; Clarke, J. D. A.

    2015-04-01

    The precise mechanisms by which martian hillside gullies erode and their dependence on the local environment remain subjects of debate. We studied three sharp rimmed craters in Noachis Terra and 37 gully profiles using Context Camera (CTX), Mars Orbiter Laser Altimeter (MOLA) and High Resolution Stereo Camera (HRSC) data. We analysed the gully topographic profiles of seven gullies and nine dry ravines. We measured slope properties using HRSC elevation data and used thermal inertia to infer material types of the gully sites. We compared these with three nearby Noachian age craters possessing crater wall slope angles within the range of previously observed gully formations. In-line with previous findings on individual gullies, we found that the slope angles of gullies in our study area consistently reflect the inherited slope angles of the host escarpment, suggesting that traditional slope-based evidence of fluvial activity in martian gullies needs to be placed in context of its local environment. We also observed a direct relationship between gully morphology and local composition of surface units. Martian gully features, and possibly method of erosion appeared heavily influenced by changes in underlying geology and presence of erodible sediment. Examples included gully shape changing in accordance with type of erodible sediment. We suggest that the degraded rims of gully-free Noachian craters precluded slope angles high enough to trigger creation of precursors to alcoves through mass wasting. Lack of these hollows has probably prevented the accumulation of enough ice-rich sediment for gullies to form in. Our analysis reveals that there is a complex interdependence between slope processes and the local environment, and global martian gully models may not work at the local scale.

  11. Water on early Mars: Possible subaqueous sedimentary deposits covering ancient cratered terrain in western Arabia and Sinus Meridiani

    NASA Astrophysics Data System (ADS)

    Edgett, Kenneth S.; Parker, Timothy J.

    1997-11-01

    Western Arabia and northern Sinus Meridiani (30 deg N-10 deg S; 40 deg W-40 deg E) are almost entirely covered by wind-eroded, horizontally-bedded, sedimentary layers that lap against local topographic features. This portion of Mars' ancient cratered terrain is relatively low (less than 1 km elevation) and flat (sloping westward 0.7 m/km over 3,000 km). The region lacks valley network channels. We propose that at some time in early Martian history, this region was under water. The water hypothesis is strengthened by the presence of (1) a shore-like contact between smooth-surfaced deposits and ancient cratered terrain in central Sinus Meridiani, (2) polygonal structures in northern Sinus Meridiani, and (3) sand (which cannot be from airfall), possibly reworked by wind from the underlying sedimentary units. The September 1997 arrival of Mars Global Surveyor's thermal emission spectrometer offers an opportunity to begin to test this hypothesis by searching for carbonate and evaporite minerals among the sediment covering the region.

  12. Compositions of Low Albedo Intracrater Materials and Wind Streaks on Mars: Examination of MGS TES Data in Western Arabia Terra

    NASA Technical Reports Server (NTRS)

    Bandfield, J. L.; Wyatt, M. B.; Christensen, P.; McSween, H. Y., Jr.

    2001-01-01

    Basalt and andesite surface compositions are identified within individual low albedo intracrater features and adjacent dark wind streaks. High resolution mapping of compositional heterogeneities may help constrain origin hypotheses for these features. Additional information is contained in the original extended abstract.

  13. Terra Sirenum

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    This image is from a region called Terra Sirenum in Mars' southern hemisphere. This region was named in 1958 for the Sea of the Sirens from Greek Mythology. This is not a sea, however, but a relatively dusty, high albedo region of Mars. There are numerous dust devil tracks that are apparent in the center- left of the image. The dust devils act like vacuum cleaners and lift dust off of the surface leaving a less dusty and relatively lower albedo surface behind. Dust devils are very common on Mars and are thought to be the primary mechanism for constantly lifting the dust into the atmosphere. Dust is constantly present in the Martian atmosphere in greater abundances than typically seen on Earth. The Martian dust is one of the main factors that affect the present Martian climate and clearly displays the relationship between Mars' geology and atmosphere.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California

  14. Related magma-ice interactions: Possible origins of chasmata, chaos, and surface materials in Xanthe, Margaritifer, Meridiani Terrae, Mars

    USGS Publications Warehouse

    Chapman, M.G.; Tanaka, K.L.

    2002-01-01

    We examine here the close spatial and temporal associations among several unique features of Xanthe and Margaritifer Terrae, specifically the Valles Marineris troughs or chasmata and their interior deposits, chaotic terrain, the circum-Chryse outflow channels, and the subdued cratered material that covers Xanthe, Margaritifer, and Meridiani Terrae. Though previous hypotheses have attempted to explain the origin of individual features or subsets of these, we suggest that they may all be related. All of these features taken together present a consistent scenario that includes the processes of sub-ice volcanism and other magma/ice interactions, results of intrusive events during Late Noachian to Early Amazonian times. ?? 2002 Elsevier Science (USA).

  15. Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: First Year Results and Second Year Work Plan

    NASA Technical Reports Server (NTRS)

    Skinner, J. A., Jr.; Rogers, A. D.; Seelos, K. D.

    2010-01-01

    The Libya Montes-Tyrrhena Terra highland-lowland transitional zone of Mars is a complex tectonic and erosional region that contains some of the oldest exposed materials on the Martian surface as well as aqueous mineral signatures that may be potential chemical artifacts of early highland formational processes. Our 1:1M scale mapping project includes the geologic materials and landforms contained within MTMs 00282, -05282, -10282, 00277, - 05277, and -10277, which cover the highland portion of the transitional zone. The map region extends from the Libya Montes southward into Tyrrhena Terra and to the northern rim of Hellas basin and includes volcanic rocks of Syrtis Major Planum and a broad lowlying plain (palus) that forms a topographic divide between Isidis and Hellas basins. The objective of this project is to describe the geologic history of regional massif and plains materials by combining geomorphological and compositional mapping observations. This abstract summarizes the technical approaches and interim scientific results of Year 1 efforts and the expected work plan for Year 2 efforts.

  16. Terra Meridiani

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site] (Released 28 June 2002) The Science This THEMIS visible image illustrates the complex terrains within Terra Meridiani. This general region is one of the more complex on Mars, with a rich array of sedimentary, volcanic, and impact surfaces that span a wide range of martian history. This image lies at the eastern edge of a unique geologic unit that was discovered by the Mars Global Surveyor Thermal Emission Spectrometer (TES) Science Team to have high concentrations of a unique mineral called grey (crystalline) hematite. As discussed by the TES Science Team, this mineral typically forms by processes associated with water, and this region appears to have undergone alteration by hydrothermal (hot water) or other water-related processes. As a result of this evidence for water activity, this region is a leading candidate for further exploration by one of NASA's upcoming Mars Exploration Rovers. The brightness and texture of the surface varies remarkably throughout this image. These differences are associated with different rock layers or ?units?, and can be used to map the occurrence of these layers. The number of layers indicates that extensive deposition by volcanic and sedimentary processes has occurred in this region. Since that time, however, extensive erosion has occurred to produce the patchwork of different layers exposed across the surface. Several distinct layers can be seen within the 20 km diameter crater at the bottom (south) of the image, indicating that this crater once contained layers of sedimentary material that has since been removed. THEMIS infrared images of this region show that many of these rock layers have distinctly different temperatures, indicating that the physical properties vary from layer to layer. These differences suggest that the environment and the conditions under which these layers were deposited or solidified varied through time as these layers were formed. The Story Mars exploration

  17. Terra Sirenum Slope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    16 July 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the layered rocks and boulders exposed on the wall of a trough in the Terra Sirenum region. The layers that erode to produce large boulders are harder and more resistant to weathering and erosion than those that do not. The slope is located near 25.8oS, 139.8oW. The image covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the upper left.

  18. Lunar and Planetary Science XXXV: Impacts on Mars and Earth

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The session "Impacts on Mars and Earth" included the following reports:A Timescale for Major Events in Early Mars Crustal Evolution; Impact Craters in Arabia Terra, Mars; Ancient Giant Basin/Aquifer System in the Arabia Region, Mars; Small Crater Morphology Within Gusev Crater and Isidis Planitia: Evidence for Widespread Secondaries on Mars; Martian Surface Properties: Inferences from Resolved Differences in Crater Geometries; Asymmetric Ramparts of Secondary Craters in Cerberus, Mars: Interpretation and Implications for Local Stratigraphy; Depth to Diameter Relationships of Craters in the High Latitudes (70 -80 ) of Mars: Implications for Geologic History of Those Areas; Impact Cratering on Mars: Search for Target Influence on Morphology; Starting Conditions for Hydrothermal Systems Underneath Martian Craters: Hydrocode Modeling; Impact-induced Hydrothermal System at the Sudbury Crater: Duration, Temperatures, Mechanics, and Biological Implications; Major and Trace Element Variations in Impact Crater Clay from Chicxulub, Lonar, and Mistastin, Implications for the Martian Soil; Stable Isotopes and Hydrothermal Fluid Source in the Yaxcopoil-1 Borehole, Chicxulub Impact Structure, Mexico; and Chicxulub Impact Melts: Geochemical Signatures of Target Lithology Mixing and Post-Impact Hydrothermal Fluid Processes.

  19. Terra Satellite

    Atmospheric Science Data Center

    2013-04-19

    ... techniques, this enables construction of 3-D models and estimation of the total amount of sunlight reflected by Earth's diverse ... Artist Concept Terra with MISR location:  Global Images thumbnail:  ...

  20. Regional-scale stratigraphy of surface units in Tyrrhena and Iapygia Terrae, Mars: Insights into highland crustal evolution and alteration history

    USGS Publications Warehouse

    Rogers, A.D.; Fergason, R.L.

    2011-01-01

    The compositional, thermophysical and geologic characteristics of surface units in Iapygia and Tyrrhena Terra (60??E-100??E, 0??-30??S) provide new insights into the compositional stratigraphy of the region. Intercrater plains are dominated by two surface units. The older unit (unit 1) is deficient in olivine and more degraded and likely consists of a mixture of impact, volcanic and sedimentary materials. The younger unit (unit 2) is enriched in olivine, exhibits a resistant morphology and higher thermal inertia, and likely represents volcanic infilling of plains. Units 1 and 2 bear a strong resemblance to those previously mapped in Mare Serpentis, a section of highlands crust located northwest of Hellas Basin. Thus, the two major intercrater plains units are even more widespread than previously thought and therefore likely constitute important components of Mars' highland stratigraphy. Many craters in the region contain high thermal inertia deposits (unit 3) that are compositionally identical to unit 2. These may have formed via volcanic infilling or may represent sedimentary materials that have been eroded from crater walls and lithified. Less common units include olivine and/or pyroxene-rich massifs and crater central peaks. These are primarily found within Hellas Basin rim units and may represent mantle materials brought toward the surface during the Hellas impact. Putative chloride deposits are primarily associated with olivine-deficient surfaces (unit 1) that may be heavily degraded occurrences of unit 2. The observations raise a variety of questions related to Martian crustal evolution and alteration that may have more widespread implications outside the study region. Copyright ?? 2011 by the American Geophysical Union.

  1. Regional-scale stratigraphy of surface units in Tyrrhena and Iapygia Terrae, Mars: insights into highland crustal evolution and alteration history

    USGS Publications Warehouse

    Rogers, A. Deanne; Fergason, Robin L.

    2011-01-01

    The compositional, thermophysical and geologic characteristics of surface units in Iapygia and Tyrrhena Terra (60°E-100°E, 0°-30°S) provide new insights into the compositional stratigraphy of the region. Intercrater plains are dominated by two surface units. The older unit (unit 1) is deficient in olivine and more degraded and likely consists of a mixture of impact, volcanic and sedimentary materials. The younger unit (unit 2) is enriched in olivine, exhibits a resistant morphology and higher thermal inertia, and likely represents volcanic infilling of plains. Units 1 and 2 bear a strong resemblance to those previously mapped in Mare Serpentis, a section of highlands crust located northwest of Hellas Basin. Thus, the two major intercrater plains units are even more widespread than previously thought and therefore likely constitute important components of Mars' highland stratigraphy. Many craters in the region contain high thermal inertia deposits (unit 3) that are compositionally identical to unit 2. These may have formed via volcanic infilling or may represent sedimentary materials that have been eroded from crater walls and lithified. Less common units include olivine and/or pyroxene-rich massifs and crater central peaks. These are primarily found within Hellas Basin rim units and may represent mantle materials brought toward the surface during the Hellas impact. Putative chloride deposits are primarily associated with olivine-deficient surfaces (unit 1) that may be heavily degraded occurrences of unit 2. The observations raise a variety of questions related to Martian crustal evolution and alteration that may have more widespread implications outside the study region.

  2. Nature and origin of materials exposed in the Oxia Palus-Western Arabia-Sinus Meridiani region, Mars

    NASA Technical Reports Server (NTRS)

    Presley, M. A.; Arvidson, R. E.

    1988-01-01

    Images and thermal data obtained by the Viking Orbiter over the Martian equatorial cratered terrain in western Arabia, eastern Oxia, and Sinuses Sabaeus and Meridiani, have been evaluated with a view to the identification, characterization, and mapping of local, bedrock-related materials. Three primary color/thermal units are discernible: (1) bright red dust storm deposits; (2) brown materials, which may be indurated; and (3) dark, but less red materials which may be composed of medium sand size-range lithic fragments. The surficial units exposed over the study area are judged to represent mixed eolian deposits, largely decoupled from the bedrock underneath.

  3. CD-ROM publication of the Mars digital cartographic data base

    NASA Technical Reports Server (NTRS)

    Batson, R. M.; Eliason, E. M.; Soderblom, L. A.; Edwards, Kathleen; Wu, Sherman S. C.

    1991-01-01

    The recently completed Mars mosaicked digital image model (MDIM) and the soon-to-be-completed Mars digital terrain model (DTM) are being transcribed to optical disks to simplify distribution to planetary investigators. These models, completed in FY 1991, provide a cartographic base to which all existing Mars data can be registered. The digital image map of Mars is a cartographic extension of a set of compact disk read-only memory (CD-ROM) volumes containing individual Viking Orbiter images now being released. The data in these volumes are pristine in the sense that they were processed only to the extent required to view them as images. They contain the artifacts and the radiometric, geometric, and photometric characteristics of the raw data transmitted by the spacecraft. This new set of volumes, on the other hand, contains cartographic compilations made by processing the raw images to reduce radiometric and geometric distortions and to form geodetically controlled MDIM's. It also contains digitized versions of an airbrushed map of Mars as well as a listing of all feature names approved by the International Astronomical Union. In addition, special geodetic and photogrammetric processing has been performed to derive rasters of topographic data, or DTM's. The latter have a format similar to that of MDIM, except that elevation values are used in the array instead of image brightness values. The set consists of seven volumes: (1) Vastitas Borealis Region of Mars; (2) Xanthe Terra of Mars; (3) Amazonis Planitia Region of Mars; (4) Elysium Planitia Region of Mars; (5) Arabia Terra of Mars; (6) Planum Australe Region of Mars; and (7) a digital topographic map of Mars.

  4. Quasi-periodic bedding in the sedimentary rock record of mars

    USGS Publications Warehouse

    Lewis, K.W.; Aharonson, O.; Grotzinger, J.P.; Kirk, R.L.; McEwen, A.S.; Suer, T.-A.

    2008-01-01

    Widespread sedimentary rocks on Mars preserve evidence of surface conditions different from the modern cold and dry environment, although it is unknown how long conditions favorable to deposition persisted. We used 1-meter stereo topographic maps to demonstrate the presence of rhythmic bedding at several outcrops in the Arabia Terra region. Repeating beds are ???10 meters thick, and one site contains hundreds of meters of strata bundled into larger units at a ???10:1 thickness ratio. This repetition likely points to cyclicity in environmental conditions, possibly as a result of astronomical forcing. If deposition were forced by orbital variation, the rocks may have been deposited over tens of millions of years.

  5. Terra Cimmeria Crater Landslide

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The landslide in this VIS image is located inside an impact crater in the Terra Cimmeria region of Mars. The unnamed crater hosting this image is just east of Molesworth Crater.

    Image information: VIS instrument. Latitude -27.7, Longitude 152 East (208 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  6. Urbanization: Riyadh, Saudi Arabia

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Riyadh, the national capital of Saudi Arabia, is shown in 1972, 1990 and 2000. Its population grew in these years from about a half million to more than two million. Saudi Arabia experienced urbanization later than many other countries; in the early 1970s its urban-rural ratio was still about 1:3. By 1990 that had reversed to about 3:1. The city grew through in-migration from rural areas, and from decreases in the death rate while birthrates remained high. The 1972 image is a Landsat MSS scene; the 1990 image is a Landsat Thematic Mapper scene; and the 2000 image is an ASTER scene. All three images cover an area of about 27 x 34 km. The image is centered at 24.6 degrees north latitude, 46.6 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  7. InfoTerra/TerraSAR initiative

    NASA Astrophysics Data System (ADS)

    Wahl, Manfred W.

    2004-01-01

    The overarching goal of the InfoTerra/TerraSAR Initiative is to establish a self-sustaining operational/commercial business built on Europe"s know-how and experience in space-borne Synthetic Aperture Radar (SAR) technology, in SAR data processing as well as in SAR applications. InfoTerra stands for a new business concept based on supplying innovative geo-information products and services. TerraSAR is a space and ground system conceived to consist of an initial deployment and operation of 2 Radar satellites (one in X- and one in L-band) flying in a tandem configuration in the same orbit. The design of TerraSAR is driven by the market and is user-oriented. TerraSAR is key to capturing a significant proportion of the existing market and to opening new market opportunities, when it becomes operational. The InfoTerra/TerraSAR Initiative has evolved gradually. It started in 1997 as a joint venture between German (DSS) and British (MMS-UK) space industry, strongly supported by both space agencies, DLR and BNSC. In early 2001, DLR and BNSC submitted to ESA the Formal Programme Proposal for InfoTerra/TerraSAR to become an essential element of ESA"s Earth Watch Programme. In summer 2001, when it became evident that there was not yet sufficient support from the ESA Member States to allow immediate start entering into TerraSAR Phase C/D, it has been decided to implement first a TerraSAR consolidation phase. In early 2002, in order to avoid further delays, a contract was signed between DLR and Astrium GmbH on the development of one component of TerraSAR, the TerraSAR-X, in the frame of a national programme, governed by a Public Private Partnership Agreement. Even if now the different launch dates for TerraSAR-X and TerraSAR-L are narrowing down the window of common data acquisition, it is a reasonable starting point, but it should always be kept in mind that the utmost goal for the longterm is to achieve self sustainability by supplying geo-information products and services

  8. Mars

    NASA Astrophysics Data System (ADS)

    McSween, H. Y., Jr.

    2003-12-01

    More than any other planet, Mars has captured our attention and fueled our speculations. Much of this interest relates to the possibility of martian life, as championed by Percival Lowell in the last century and subsequently in scientific papers and science fiction. Lowell's argument for life on Mars was based partly on geochemistry, in that his assessmentof the planet's hospitable climate was dependent on the identification of H2O ice rather than frozen CO2 in the polar caps. Although this reasoning was refuted by Alfred Wallace in 1907, widespread belief in extant martian life persisted within the scientific community until the mid-twentieth century (Zahnle, 2001). In 1965 the Mariner 4 spacecraft flyby suddenly chilled this climate, by demonstrating that the martian atmosphere was thin and the surface was a cratered moonscape devoid of canals. This view of Mars was overturned again in 1971, when the Mariner 9 spacecraft discovered towering volcanoes and dry riverbeds, implying a complex geologic history. The first geochemical measurements on Mars, made by two Viking landers in 1976, revealed soils enriched in salts suggesting exposure to water, but lacking organic compounds which virtually ended discussion of martian life.The suggestion that a small group of achondritic meteorites were martian samples (McSween and Stolper, 1979; Walker et al., 1979; Wasson and Wetherill, 1979) found widespread acceptance when trapped gases in them were demonstrated to be compositionally similar to the Mars atmosphere ( Bogard and Johnson, 1983; Becker and Pepin, 1984). The ability to perform laboratory measurements of elements and isotopes present in trace quantities in meteorites has invigorated the subject of martian geochemistry. Indeed, because of these samples, we now know more about the geochemistry of Mars than of any other planet beyond the Earth-Moon system. Some studies of martian meteorites have prompted a renewed search for extraterrestrial life using chemical

  9. Evolution of Lacustrine Environments on Mars and Their Significance: The Case for the Brazos Lakes and East Terra Meridiani Basins as Landing Sites for Surveyor 2001

    NASA Astrophysics Data System (ADS)

    Cabrol, N. A.; Grin, E. A.

    1999-01-01

    Ancient Martian lacustrine environments must be considered as primary targets to explore on Mars. Terrestrial studies show that lakes are exceptional sites to keep the record of the evolution of climate, geology, water and life. Finding this record is also the principal objective of the Mars Surveyor Program. This record encompasses changes at local, regional and global scales. Lacustrine sediments provide critical information about all events occurring in the lake catchment area. They are also a locus of complex chemical processes, concentration for life and favorable sites for fossilization processes to take place. We proposed two candidate-sites in the Schiaparelli Crater region responding to this high-priority scientific objective at the June 1999 meeting in Buffalo, NY. The two sites are located in the Sinus Sabeus quadrangle, are well documented by MOC images, and are among the best evidence yet of a Martian past lacustrine activity. We develop their case as high-priority sites for the 01' mission.

  10. Rippled Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    29 July 2004 Hundreds of large ripples or small dunes cover the landscape in the Terra Tyrrhena region of Mars in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image. The winds responsible for these dunes blew from the north-northwest (top/upper left). This scene is located near 8.8oS, 252.8oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the terrain from the left.

  11. Exobiology site priorities for Mars Pathfinder

    NASA Technical Reports Server (NTRS)

    Farmer, Jack D.; Desmarais, David J.

    1994-01-01

    The fact that life developed on the Earth within the first billion years of its history makes it quite plausible that life may have also developed on Mars. If life did develop on Mars, it undoubtedly left behind a fossil record. Such a fossil record is likely to be more accessible than either subsurface environments that may harbor life, or scattered 'oases' that may be present at the surface. Consequently, the post-Viking approach of Mars exobiology has shifted focus to search for evidence of an ancient martian biosphere. This has led to the emergence of a new subdiscipline of paleontology, herein termed 'exopaleontology', which deals with the exploration for fossils on other planets and whose core concepts derive from Earth-based Precambrian paleontology, microbial ecology, and sedimentology. Potential targets on Mars for subaqueous spring deposits, sedimentary cements, and evaporites are ancient terminal lake basins where hydrological systems could have endured for some time under arid conditions. Potential targets for the Mars Pathfinder mission include channeled impact craters and areas of deranged drainage associated with outflows in northwest Arabia and Xanthe Terra, where water may have ponded temporarily to form lakes. The major uncertainty of such targets is their comparatively younger age and the potentially short duration of hydrological activity compared to older paleolake basins found in the southern hemisphere. However, it has been suggested that cycles of catastrophic flooding associated with Tharsis volcanism may have sustained a large body of water, Oceanus Borealis, in the northern plains area until quite late in martian history. Although problematic, the shoreline areas of the proposed northern ocean provide potential targets for a Mars Pathfinder mission aimed at exploring for carbonates or other potentially fossiliferous marine deposits. Carbonates and evaporites possess characteristic spectra signatures in the near-infrared and should be

  12. Saudi Arabia.

    PubMed

    1986-12-01

    In 1985, Saudi Arabia's population stood at 9.6 million, with an annual growth rate of 2.8%. The infant mortality rate was 78/1000 and life expectancy was 60 years. Literacy was at the 50% level among men and 25% among women. Of the work force of 3 million, 66% are foreign workers. The labor force is distributed as follows: agriculture, 14%; industry, 11%; services, commerce, and government, 53%; construction, 20%; and oil and mining, 2%. The GDP was US$98.1 billion in 1985-86, with an annual growth rate of 8% and a per capita GDP of $9800. Under the impact of rapid economic growth, urbanization has advanced rapidly and 95% of the population is now settled. Saudi Arabia, a monarchy, is divided into 14 provinces that are governed by princes or relatives of the royal family. Oil is the major source of foreign exchange, contributing 81% of government revenues. Ample government funds and foreign exchange resources are available for development, defense, and aid to other Arab and Islamic countries. The government has sought to allocate its petroleum income to transform its relatively undeveloped oil-based economy into that of a modern industrial state while maintaining traditional Islamic values. The standard of living of most Saudis has improved significantly. A shortage of skilled workers at all levels remains the principal obstacle to rapid development. PMID:12178138

  13. Nature and origin of the hematite-bearing plains of Terra Meridiani based on analyses of orbital and Mars Exploration rover data sets

    USGS Publications Warehouse

    Arvidson, R. E.; Poulet, F.; Morris, R.V.; Bibring, J.-P.; Bell, J.F., III; Squyres, S. W.; Christensen, P.R.; Bellucci, G.; Gondet, B.; Ehlmann, B.L.; Farrand, W. H.; Fergason, R.L.; Golombeck, M.; Griffes, J.L.; Grotzinger, J.; Guinness, E.A.; Herkenhoff, K. E.; Johnson, J. R.; Klingelhofer, G.; Langevin, Y.; Ming, D.; Seelos, K.; Sullivan, R.J.; Ward, J.G.; Wiseman, S.M.; Wolff, M.J.

    2006-01-01

    The ???5 km of traverses and observations completed by the Opportunity rover from Endurance crater to the Fruitbasket outcrop show that the Meridiani plains consist of sulfate-rich sedimentary rocks that are largely covered by poorly-sorted basaltic aeolian sands and a lag of granule-sized hematitic concretions. Orbital reflectance spectra obtained by Mars Express OMEGA over this region are dominated by pyroxene, plagioclase feldspar, crystalline hematite (i.e., concretions), and nano-phase iron oxide dust signatures, consistent with Pancam and Mini-TES observations. Mo??ssbauer Spectrometer observations indicate more olivine than observed with the other instruments, consistent with preferential optical obscuration of olivine features in mixtures with pyroxene and dust. Orbital data covering bright plains located several kilometers to the south of the landing site expose a smaller areal abundance of hematite, more dust, and a larger areal extent of outcrop compared to plains proximal to the landing site. Low-albedo, low-thermal-inertia, windswept plains located several hundred kilometers to the south of the landing site are predicted from OMEGA data to have more hematite and fine-grained olivine grains exposed as compared to the landing site. Low calcium pyroxene dominates spectral signatures from the cratered highlands to the south of Opportunity. A regional-scale model is presented for the formation of the plains explored by Opportunity, based on a rising ground water table late in the Noachian Era that trapped and altered local materials and aeolian basaltic sands. Cessation of this aqueous process led to dominance of aeolian processes and formation of the current configuration of the plains. Copyright 2006 by the American Geophysical Union.

  14. Sand Dunes in Noachis Terra

    NASA Technical Reports Server (NTRS)

    2004-01-01

    11 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark-toned sand dunes in a crater in eastern Noachis Terra. Most big martian dunes tend to be dark, as opposed to the more familiar light-toned dunes of Earth. This difference is a product of the composition of the dunes; on Earth, most dunes contain abundant quartz. Quartz is usually clear (transparent), though quartz sand grains that have been kicked around by wind usually develop a white, frosty surface. On Mars, the sand is mostly made up of the darker minerals that comprise iron- and magnesium-rich volcanic rocks--i.e., like the black sand beaches found on volcanic islands like Hawaii. Examples of dark sand dunes on Earth are found in central Washington state and Iceland, among other places. This picture is located near 49.0oS, 326.3oW. Sunlight illuminates this scene from the upper left; the image covers an area 3 km (1.9 mi) wide.

  15. Medusae Fossae-Elysium Region, Mars: Depression in the HEND/Odyssey Map of Mars Epithermal Neutrons

    NASA Technical Reports Server (NTRS)

    Ivanov, M. A.; Litvak, M. L.; Mitrofanov, I. G.; Boynton, W.; Saunders, R. S.

    2003-01-01

    The first data from the Gamma Ray Spectrometer (GRS) onboard Mars Odyssey spacecraft showed that the low neutron fluxes characterize both subpolar regions of Mars. The low neutron fluxes mean the presence of hydrogen-rich soils and have been interpreted as an indication on abundant water ice in these areas. The equatorial region of Mars (equatorward of approx. 50 deg) is characterized by higher fluxes of both epithermal (0.4 eV-100 keV, come from depth 1-2 m) and fast (3.4-7.3 MeV, come from depth 0.2-0.3 m) neutrons meaning that this area is mostly dry. The pattern of distribution of the neutron fluxes is in a good agreement with the theoretical predictions on the stability of ground ice on present Mars. The actual distribution of the ice, however, depends on variations of thermal inertia of soils and albedo of the surface. The flux of the epithermal neutrons detected by the HEND instrument, which is part of GRS, has two noticeable depressions in the equatorial region, one in Arabia Terra and another in the Medusae Fossae-Elysium region (MFER). Here we present the initial results of analysis of characteristics of the neutron fluxes and regional geological setting of the epithermal neutron depression in this area. The main goal of our study was to put some constraints on the time of the anomaly formation and to assess possible form of hydrogen (ground ice vs. chemically bound water) there.

  16. NASA Remote Sensing Validation Data: Saudi Arabia

    DOE Data Explorer

    Myers, Daryl R. [NREL; Al-Abbadi, Naif [King Abdulaziz City for Science and Technology, Energy Research Institite; Wilcox, Steve [NREL

    Since 1995, the King Abdulaziz City for Science and Technology (KACST) and the National Renewable Energy Laboratory (NREL) have co-operated to establish a 12 station network of high quality solar radiation monitoring installations across the Kingdom of Saudi Arabia. NREL and KACST realized the value of accurate surface solar radiation flux measurements for validation of satellite derived surface and atmospheric solar radiation flux measurements, and is making this data available to support validation of satellite data products related to the NASA Mission to Planet Earth component of the Earth Science Enterprise Earth Observing System (EOS) project to evaluate long term climate trends based on measuements from EOS Terra Platforms. A CIMEL 8 channel sunphotometer for measuring aerosol optical depth at 6 wavelengths and total column water has been deployed at the Solar Village station since February 24, 1999. [Taken from http://rredc.nrel.gov/solar/new_data/Saudi_Arabia/

  17. EOS Terra Validation Program

    NASA Technical Reports Server (NTRS)

    Starr, David

    1999-01-01

    The EOS Terra mission will be launched in July 1999. This mission has great relevance to the atmospheric radiation community and global change issues. Terra instruments include ASTER, CERES, MISR, MODIS and MOPITT. In addition to the fundamental radiance data sets, numerous global science data products will be generated, including various Earth radiation budget, cloud and aerosol parameters, as well as land surface, terrestrial ecology, ocean color, and atmospheric chemistry parameters. Significant investments have been made in on-board calibration to ensure the quality of the radiance observations. A key component of the Terra mission is the validation of the science data products. This is essential for a mission focused on global change issues and the underlying processes. The Terra algorithms have been subject to extensive pre-launch testing with field data whenever possible. Intensive efforts will be made to validate the Terra data products after launch. These include validation of instrument calibration (vicarious calibration) experiments, instrument and cross-platform comparisons, routine collection of high quality correlative data from ground-based networks, such as AERONET, and intensive sites, such as the SGP ARM site, as well as a variety field experiments, cruises, etc. Airborne simulator instruments have been developed for the field experiment and underflight activities including the MODIS Airborne Simulator (MAS), AirMISR, MASTER (MODIS-ASTER), and MOPITT-A. All are integrated on the NASA ER-2, though low altitude platforms are more typically used for MASTER. MATR is an additional sensor used for MOPITT algorithm development and validation. The intensive validation activities planned for the first year of the Terra mission will be described with emphasis on derived geophysical parameters of most relevance to the atmospheric radiation community. Detailed information about the EOS Terra validation Program can be found on the EOS Validation program

  18. EOS Terra Validation Program

    NASA Technical Reports Server (NTRS)

    Starr, David

    2000-01-01

    The EOS Terra mission will be launched in July 1999. This mission has great relevance to the atmospheric radiation community and global change issues. Terra instruments include Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Clouds and Earth's Radiant Energy System (CERES), Multi-Angle Imaging Spectroradiometer (MISR), Moderate Resolution Imaging Spectroradiometer (MODIS) and Measurements of Pollution in the Troposphere (MOPITT). In addition to the fundamental radiance data sets, numerous global science data products will be generated, including various Earth radiation budget, cloud and aerosol parameters, as well as land surface, terrestrial ecology, ocean color, and atmospheric chemistry parameters. Significant investments have been made in on-board calibration to ensure the quality of the radiance observations. A key component of the Terra mission is the validation of the science data products. This is essential for a mission focused on global change issues and the underlying processes. The Terra algorithms have been subject to extensive pre-launch testing with field data whenever possible. Intensive efforts will be made to validate the Terra data products after launch. These include validation of instrument calibration (vicarious calibration) experiments, instrument and cross-platform comparisons, routine collection of high quality correlative data from ground-based networks, such as AERONET, and intensive sites, such as the SGP ARM site, as well as a variety field experiments, cruises, etc. Airborne simulator instruments have been developed for the field experiment and underflight activities including the MODIS Airborne Simulator (MAS) AirMISR, MASTER (MODIS-ASTER), and MOPITT-A. All are integrated on the NASA ER-2 though low altitude platforms are more typically used for MASTER. MATR is an additional sensor used for MOPITT algorithm development and validation. The intensive validation activities planned for the first year of the Terra

  19. Plains Style Caldera Complexes: Evidence for Ancient, Explosive Volcanism on Mars

    NASA Astrophysics Data System (ADS)

    Michalski, J. R.; Bleacher, J. E.

    2014-12-01

    One of the mysteries of Mars' geology is the origin of widespread, layered, friable deposits that likely formed through air fall deposition. The enigmatic chaos terrains are largely composed of such deposits, as are many of the most intriguing layered, clay- and sulfate-bearing deposits of astrobiological interest. Such deposits are most likely of volcanic origin, but lack an obvious source, based on comparison with well-known volcanic provinces [1]. We suggest that these deposits may have been sourced from previously unrecognized explosive volcanoes in Arabia Terra. While Arabia is not traditionally considered to be a volcanic region, we propose that several of the large depressions in the area are in fact calderas that formed through a combination of structural collapse and explosive volcanism. These features are characterized by the observation of sets of nested depressions, association with ridged plains, development of ring fractures and faults, the presence of interior slump blocks, and direct association, in some cases, with friable deposits, lavas and evidence for lava lakes. Eden Patera is the type example and shows evidence for three nested calderas with >4000 km3 of collapse volume. Siloe Patera also contains a set of nested collapse features that occur within a zone of demagnetized crust that might indicate the presence of a magma chamber at shallow depth [2]. It is not yet clear why explosive volcanoes may have formed in Arabia Terra, but we suggest that they might represent the rapid rise of mafic magmas through a thin crust. They might represent more silicic or volatile-rich magmas, but these scenarios do not appear to be necessary [3]. We suggest that explosive mafic volcanism was an important aspect of early Martian geological processes. [1] Kerber, L., Head III, J., Madeleine, J. B., Forget, F. & Wilson, L. The dispersal of pyroclasts from ancient explosive volcanoes on Mars: Implications for the friable layered deposits. Icarus 219, 358-381 (2012

  20. Can hydrous minerals account for the observed mid-latitude water on Mars?

    SciTech Connect

    Bish, D. L.; Vaniman, D. T.; Fialips, C. I.; Carey, J. W.; Feldman, W. C.

    2003-01-01

    Great interest was generated with the discovery by the Odyssey spacecraft OC heterogeneously distributed hydrogcn at martian mid-latitudes, suggesting that large areas of the near-equatorial highlands contain near-surface deposits of 'chemically and/or physically bound 1120 and/or OH' in amounts up to 3.8% equivalent H20. More recent interpretations of the Odyssey data using new calibrations suggest that some near-equatorial areas, such as Arabia Terra, contain up to 8.5f I .3% water-equivalent hydrogen. Such shallow occurrences (Mars, and both groups of minerals are common terrestrial alteration products of hydrovolcanic basaltic ashes and palagonitic material comparable io those that may be widespread on Mars. Smectites within martian meteorites, attributed to hydrous alteration on Mars rather than on Earth, provide direct evidence of clay minerals from Mars. In addition, new thermal emission spectrometer (TES) data provide evidence for unspecified zeolites in martian surface dust, and concluded that spectral deconvolution of MGS TES and Mariner 9 IRIS data is consistent with the presence of zeolite in the martian surface dust.

  1. Xanthe Terra Landslide in IR

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    This is a daytime IR image of a chaos region within Xanthe Terra. As with earlier images, the landslide in this image is caused by the failure of steep slopes releasing material to form the landslide deposit.

    Image information: IR instrument. Latitude 3.1, Longitude 309.7 East (50.3 West). 100 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  2. Resurfacing history of Tempe Terra and surroundings

    SciTech Connect

    Frey, H.V. ); Grant, T.D. )

    1990-08-30

    The resurfacing history of the Tempe Terra region is determined using the Neukum and Hiller technique of breaking cumulative frequency curves into separate branches where the curves depart from a standard production curve. We find four surfaces recorded in the heavily cratered portions of Tempe Terra, with crater retention ages N(1) = (242,100), (95,700), (20,800), and (5,500). This is interpreted to indicate three major resurfacing events occurred in this region, ending at N(1) = (95,700), (20,800), and (5,500). The ridged plains on the Tempe Terra plateau have an oldest recorded surface age of (20,400), identical to that of the second resurfacing event recorded in the heavily cratered areas. A single resurfacing of the ridged plains (which may have been a second episode of ridged plains volcanism) occurred at N(1) = (7,800). The knobby plains to the north west and east of Tempe Terra also show a resurfacing at (20,000) and additional events at (5,400) and perhaps (1,600). Mottled plains to the northeast record surfaces with crater retention age (7,500), (5,000), and (3,900), where the first age is determined by a single surviving crater. It appears that the Lunae Planum Age (LPA) (at N(1) = (20,000)) resurfacing event seen elsewhere on mars was widespread and effective in this region. A second widespread event appears to have ended at N(1) = (5,000). The authors estimate the thickness of the resurfacing materials corresponding to the LPA event to be less than 90 m in the heavily cratered areas but 300-500 m in the ridged plains themselves. Later resurfacing materials were generally thicker farther north in the mottled plains (300 m) than in the knobby plains (200 m).

  3. Slope Streaks in Terra Sabaea

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Figure 1 Click on image for larger version

    This HiRISE image shows the rim of a crater in the region of Terra Sabaea in the northern hemisphere of Mars.

    The subimage (figure 1) is a close-up view of the crater rim revealing dark and light-toned slope streaks. Slope streak formation is among the few known processes currently active on Mars. While their mechanism of formation and triggering is debated, they are most commonly believed to form by downslope movement of extremely dry sand or very fine-grained dust in an almost fluidlike manner (analogous to a terrestrial snow avalanche) exposing darker underlying material.

    Other ideas include the triggering of slope streak formation by possible concentrations of near-surface ice or scouring of the surface by running water from aquifers intercepting slope faces, spring discharge (perhaps brines), and/or hydrothermal activity.

    Several of the slope streaks in the subimage, particularly the three longest darker streaks, show evidence that downslope movement is being diverted around obstacles such as large boulders. Several streaks also appear to originate at boulders or clumps of rocky material.

    In general, the slope streaks do not have large deposits of displaced material at their downslope ends and do not run out onto the crater floor suggesting that they have little reserve kinetic energy. The darkest slope streaks are youngest and can be seen to cross cut and superpose older and lighter-toned streaks. The lighter-toned streaks are believed to be dark streaks that have lightened with time as new dust is deposited on their surface.

    Observation Geometry Image PSP_001808_1875 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 15-Dec-2006. The complete image is centered at 7.4 degrees latitude, 47.0 degrees East longitude. The range to the target site was 272.1 km

  4. Cratered terrain in Terra Meridiani

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 30 April 2002) The Science This THEMIS visible image shows a region in Terra Meridiani near -12o S, 358o W (2o E). An old, heavily degraded channel can be seen from the lower (southern) portion of the image toward the top. This channel appears to terminate abruptly at the rim of a 10 km diameter crater. This apparent 'superposition' of the crater on top of the channel suggests that the impact crater was created after the channel was formed. This crater has two 3-km sized blocks of material that have slumped off from the lower left segment of the original crater rim. These immense blocks must have moved as a single unit because the rock layers that can be seen in the original wall of the crater can still be seen in these detached blocks. The walls of several craters in this image show vague hints of possible gully formation at the bottom of pronounced rock layers, with the suggestion of alcoves above the individual gullies. Well-developed gullies that were imaged by the Mars Orbiter Camera (MOC) on Mars Global Surveyor have been suggested to form by seepage and runoff of a fluid. The MOC has observed these gullies in numerous craters and channels further south, but they are uncommon at latitudes this close to the equator. Several sections of the crater walls appear to have ridges and troughs formed by the dry avalanche of loose rock, and a similar process of dry avalanche may account for the gullies seen in this THEMIS image. Patches of lighter material, possibly small dunes ripples, can be seen in several places throughout this image. The Story When the walls come tumbling down! Take a closer look at the bright linear ridges within a deep crater near the center of this image (bottom, left-hand side of the crater). Almost 2 miles long, these chunks of material slumped off the crater side in one fell swoop. Phoozhj! Down they came as one massive unit. You can tell, because the rock layers seen in the original wall of the crater are also still there in the

  5. Occurrence and origin of rhythmic sedimentary rocks on Mars

    NASA Astrophysics Data System (ADS)

    Lewis, Kevin W.; Aharonson, Oded

    2014-06-01

    Sedimentary rocks preserved on the surface of Mars represent a natural archive of past climate conditions. Although the details of their formation often remain poorly constrained, the recent detection of rhythmic bedding patterns in the Arabia Terra region suggests the influence of orbital variations on sedimentary deposition. Here we detail a number of new sites which exhibit quasiperiodic stratigraphic variations, demonstrating their occurrence throughout the equatorial region of the planet. We characterize these recorded signals as well as the local geomorphic context and structural attributes. Two cyclic units are identified within Gale crater, the landing site of the Mars Science Laboratory mission, enabling estimation of possible formation timescales for the geologic units that may be studied in situ by the rover. We find a general lack of fluvial features in connection with rhythmic geologic units, contrasting these sites with the aperiodic deltaic stratigraphy found at Eberswalde crater. Possible formation scenarios and their climatic implications are discussed for the diverse set of quasiperiodic sedimentary units. We propose multiple depositional pathways for recording cyclic climate changes, including repeated evaporitic precipitation from groundwater discharge in topographic lows as well as largely anhydrous accumulation of atmospheric dust for deposits outside of confined basins. The preservation of orbital signals in sediments distributed across a wide range of geographic settings suggests a pervasive influence on Martian climate conditions through time.

  6. Seasonal Frost in Terra Sirenum

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This image of the Terra Sirenum region of Mars was taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) at 0918 UTC (4:18 a.m. EST) on Nov. 25, 2006, near 38.9 degrees south latitude, 195.9 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 18 meters (60 feet) across.

    At this time, Mars' southern hemisphere was experiencing mid-winter. During Martian southern winter, the southern polar cap is covered and surrounded by carbon dioxide frost and water frost. This is unlike Earth, whose frozen winter precipitation is made up of only one volatile -- water. The carbon dioxide frost evaporates, or sublimates, at a lower temperature than water frost. So, during spring, the carbon dioxide ice evaporates first and leaves a residue of water frost, which later sublimates as well.

    The image shown here covers part of a crater rim, which is illuminated from the upper left. North is at the top. The topography creates a cold microenvironment on the south side of the rim that is partially protected from solar illumination. That cold surface contains an outlier of the southern seasonal frost about 15 degrees of latitude closer to the equator than the average edge of the frost at this season.

    The top image was constructed from three infrared wavelengths that highlight the bluer color of frost than the background rock and soil. Note that the frost occurs both on sunlit and shaded surfaces on the south side of the rim. The shaded areas are still visible because they are illuminated indirectly by the Martian sky.

    The bottom image was constructed by measuring the depths of spectral absorption bands due to water frost and carbon dioxide frost, and displaying the results in image form. Blue shows strength of an absorption due to water frost near 1.50 micrometers, and green shows strength of an absorption due to carbon dioxide frost near 1.45 micrometers. Red shows

  7. Mars Digital Image Mosaic Globe

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The photomosaic that forms the base for this globe was created by merging two global digital image models (DIM's) of Mars-a medium-resolution monochrome mosaic processed to emphasize topographic features and a lower resolution color mosaic emphasizing color and albedo variations.

    The medium-resolution (1/256 or roughly 231 m/pixel) monochromatic image model was constructed from about 6,000 images having resolutions of 150-350 m/pixel and oblique illumination (Sun 20 o -45 o above the horizon). Radiometric processing was intended to suppress or remove the effects of albedo variations through the use of a high-pass divide filter, followed by photometric normalization so that the contrast of a given topographic slope would be approximately the same in all images.

    The global color mosaic was assembled at 1/64 or roughly 864 m/pixel from about 1,000 red- and green-filter images having 500-1,000 m/pixel resolution. These images were first mosaiced in groups, each taken on a single orbit of the Viking spacecraft. The orbit mosaics were then processed to remove spatially and temporally varying atmospheric haze in the overlap regions. After haze removal, the per-orbit mosaics were photometrically normalized to equalize the contrast of albedo features and mosaiced together with cosmetic seam removal. The medium-resolution DIM was used for geometric control of this color mosaic. A green-filter image was synthesized by weighted averaging of the red- and violet-filter mosaics. Finally, the product seen here was obtained by multiplying each color image by the medium-resolution monochrome image. The color balance selected for images in this map series was designed to be close to natural color for brighter, redder regions, such as Arabia Terra and the Tharsis region, but the data have been stretched so that the relatively dark regions appear darker and less red than they actually are.

    The images are presented in a projection that portrays the entire surface of Mars in a

  8. Small Volcano in Terra Cimmeria

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 26 June 2002) The Science This positive relief feature (see MOLA context) in the ancient highlands of Mars appears to be a heavily eroded volcanic center. The top of this feature appears to be under attack by the erosive forces of the martian wind. Light-toned streaks are visible, trending northeast to southwest, and may be caused by scouring of the terrain, or they may be dune forms moving sand. The northeast portion of the caldera area looks as though a layer of material is being removed to expose a slightly lighter-toned surface underneath. The flanks of this feature are slightly less cratered than the surrounding terrain, which could be explained in two ways: 1) this feature may be younger than the surrounding area, and has had less time to accumulate meteorite impacts, or 2) the slopes that are observed today may be so heavily eroded that the original, cratered surfaces are now gone, exposing relatively uncratered rocks. Although most of Terra Cimmeria has low albedo, some eastern portions, such as shown in this image, demonstrate an overall lack of contrast that attests to the presence of a layer of dust mantling the surface. This dust, in part, is responsible for the muted appearance and infill of many of the craters at the northern and southern ends of this image The Story This flat-topped volcano pops out from the surface, the swirls of its ancient lava flows running down onto the ancient highlands of Mars. Its smooth top appears to be under attack by the erosive forces of the martian wind. How can you tell? Click on the image above for a close-up look. You'll see some light-toned streaks that run in a northeast-southwest direction. They are caused either by the scouring of the terrain or dunes of moving sand. Either way, the wind likely plays upon the volcano's surface. Look also for the subtle, nearly crescent shaped feature at the northeast portion of the volcano's cap. It looks as if a layer of material has been removed by the wind, exposing

  9. A simple model of clastic sediments on Mars

    NASA Technical Reports Server (NTRS)

    Christensen, Philip R.; Malin, Michael C.

    1993-01-01

    In preparation for the start of Mars Observer operations at Mars later this year, Viking Infrared Thermal Mapper (IRTM) observations were synthesized into a simple but geologically coherent conceptual model for use in establishing targets for coordinated Thermal Emission Spectrometer (TES) and Mars Observer Camera (MOC) observations. The model is based on three assumptions that are, at best, only partly true: that albedo is a measure of the presence or absence of dust; that thermal inertia is a measure of the weighted average particle size; and that rock abundance is a measure of the statistical thickness of fine sediment (i.e., that the observed areal abundance of rock reflects the whole or partial burial of rocks). Using this model, it is possible to show that, on the scale of 30 km, mantles of wind-transportable sediment (dust and sand) are at most about 1 m thick, and that on a global average such mantles are about 35 cm thick. It is shown that 3.8 x 10(exp 19) cu cm of such sediment covers Mars equatorward of +/- 60 deg latitude. Using the model, interpretation of digital maps of IRTM data focus attention not only on areas where dust is the primary sediment (e.g., Arabia Terra), but also on areas where sand is the primary sediment (e.g., eastern Valles Marineris) and where rocks and other coarse materials are abundant (e.g., eastern Kasei Vallis). Three IRTM data sets are used in the analysis: Viking 1 and 2 pre-dawn observations mosaiced into a global map of single-point thermal inertias at 0.5 deg/bin resolution; Pleskot and Miner's global albedo map using the best available, clear-period IRTM observations (1x/bin); and Christensen's 1 deg/bin rock abundance map. Uncertainty analyses indicate these data sets to be accurate to 5 percent, 2 percent, and 20 percent, respectively.

  10. Terra is in NORMAL Mode

    Atmospheric Science Data Center

    2016-02-23

    ... 22, 2016.  TERRA has recovered from Safe Hold and is now in Normal mode. CERES will hold their CAM Wednesday morning and will ... . You can learn more about this mission at the Terra web site. The Flight Operations Team is working on resolving the issue as ...

  11. Northern Terra Meridiani's 'Monument Valley'

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Northern Terra Meridiani, near the intersection of the martian equator and prime meridian, is a region of vast exposures of layered rock. A thermal image from the Phobos 2 orbiter in 1989 showed these materials to be anomalously cool during the daytime, an observation very suggestive of dense, hardened materials like rock. Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images of this region show layered material exposed in cliffs, buttes, and mesas that in some ways resemble the rock outcrops of northern Arizona and southeastern Utah in North America (e.g., Monument Valley, Canyonlands, Zion National Park, Four Corners). MGS MOC Extended Mission operations have included several hundred opportunities for the spacecraft to be rolled off-nadir (i.e., at an angle other than 'straight down') to take pictures that repeat earlier MOC coverage. These repeat images, because they are taken from a different angle, can be combined with the original picture to produce a stereoscopic ('3-D') view. The image shown here is a composite of two pictures, the first taken October 23, 2000, the second acquired by pointing the spacecraft off-nadir on May 15, 2001. This view shows four buttes and a pinnacle (near left-center) composed of eroded, layered rock. The four buttes are each capped by the remains of a single layer of rock that is harder than the materials beneath it. It is the presence of this cap rock that has permitted these buttes to remain standing after surrounding materials were eroded away. Like the buttes of Monument Valley in the Navajo Nation on the Arizona/Utah border, these are believed to consist of sedimentary rocks, perhaps deposited in water or by wind, though some scientists have speculated that they could be made of thick accumulations of volcanic ash. The image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the left. To see the image in 3-D, red (left-eye) and blue (right-eye) '3-D' glasses are required.

  12. Lithostratigraphical analysis in northern Sinus Meridiani, Mars.

    NASA Astrophysics Data System (ADS)

    Baioni, D.; Sgavetti, M.; Tampella, G.; Wezel, F. C.

    2012-04-01

    In the Terra Meridiani- Arabia Terra region of Mars, layered rock units with a range of stratal patterns have been widely reported in the literature, and the record of the spectral signatures indicative of hydrate minerals suggests the existence of aqueous activity in at least some of the stratigraphic units. . In this work we investigated the area in the northern region of Sinus Meridiani located between 2°N to 3°N latitude and 2°W to 1°E longitude, using multiple remote sensing data sets to identify, characterize in detail, and understand the origin and evolution of the selected units in this region of Mars. MOLA and HiRISE data were used in combination to classify and correlate surface units recorded in distinct stratigraphic logs, based on planimetric configuration, topography, morphological and litho-facies characteristics. In particular, detailed analyses were focused on the layered units discovered in the walls of two impact craters located at a distance of about 100 km to each other within the study area. The stratigraphic interval analysed here corresponds to the upper part of the well known "light-toned layered deposits" identified by several authors. Distinct competent layers are observed in the internal slopes of both craters. Our observations indicate that the lithostratigraphic sections can be divided in three units. The lower unit consists of very thick bodies of light-toned bouldery breccia deposits. In the HiRISE images these white-coloured beds are composed of irregularly-shaped, white nodules which are either isolated or coalescent, distributed between bedding planes. The middle unit mainly consists of alternating thin strong layers and thicker sequences of relatively weak layers, horizontally bedded. The strong, competent layers maintain steeper erosional profiles and play a major role in controlling the overall shape and geomorphology of the wall slopes. The upper unit can be traced laterally in the surrounding ground level, displaying mesa

  13. Highest-Resolution View of 'Face on Mars'

    NASA Technical Reports Server (NTRS)

    2001-01-01

    A key aspect of the Mars Global Surveyor (MGS) Extended Mission is the opportunity to turn the spacecraft and point the Mars Orbiter Camera (MOC) at specific features of interest. A chance to point the spacecraft comes about ten times a week. Throughout the Primary Mission (March 1999 - January 2001), nearly all MGS operations were conducted with the spacecraft pointing 'nadir'--that is, straight down. In this orientation, opportunities to hit a specific small feature of interest were in some cases rare, and in other cases non-existent. In April 1998, nearly a year before MGS reached its Primary Mission mapping orbit, several tests of the spacecraft's ability to be pointed at specific features was conducted with great success (e.g., Mars Pathfinder landing site, Viking 1 site, and Cydonia landforms). When the Mars Polar Lander was lost in December 1999, this capability was again employed to search for the missing lander. Following the lander search activities, a plan to conduct similar off-nadir observations during the MGS Extended Mission was put into place. The Extended Mission began February 1, 2001. On April 8, 2001, the first opportunity since April 1998 arose to turn the spacecraft and point the MOC at the popular 'Face on Mars' feature.

    Viking orbiter images acquired in 1976 showed that one of thousands of buttes, mesas, ridges, and knobs in the transition zone between the cratered uplands of western Arabia Terra and the low, northern plains of Mars looked somewhat like a human face. The feature was subsequently popularized as a potential 'alien artifact' in books, tabloids, radio talk shows, television, and even a major motion picture. Given the popularity of this landform, a new high-resolution view was targeted by pointing the spacecraft off-nadir on April 8, 2001. On that date at 20:54 UTC (8:54 p.m., Greenwich time zone), the MGS was rolled 24.8o to the left so that it was looking at the 'face' 165 km to the side from a distance of about 450 km

  14. Bilateral symmetry across Aphrodite Terra

    NASA Technical Reports Server (NTRS)

    Crumpler, L. S.; Head, J. W.; Campbell, D. B.

    1987-01-01

    There are three main highland areas on Venus: Beta Regio, Ishtar Terra and Aphrodite Terra. The latter is least known and the least mapped, yet existing analyses of Aphrodite Terra based on available Pioneer-Venus orbiter data suggest that it may be the site of extensive rifting. Some of the highest resolution (30 km) PV data (SAR) included most of the western half of Aphrodite Terra. Recent analysis of the SAR data together with Arecibo range-doppler topographic profiling (10 X 100 km horizontal and 10 m vertical resolution) across parts of Aphrodite, further characterized the nature of possible tectonic processes in the equatorial highlands. The existence of distinct topographic and radar morphologic linear discontinuities across the nearly east-west strike of Aphrodite Terra is indicated. Another prominent set of linear features is distinctly parallel to and orthogonal to the ground tracks of the PV spacecraft and are not included because of the possibility that they are artifacts. Study of the northwest trending cross-strike discontinuities (CSD's) and the nature of topographic and morphologic features along their strike suggest the presence of bilateral topographic and morphologic symmetry about the long axis of Aphrodite Terra.

  15. A hypersaline spring analogue in Manitoba, Canada for potential ancient spring deposits on Mars

    NASA Astrophysics Data System (ADS)

    Berard, Genevieve; Applin, Daniel; Cloutis, Edward; Stromberg, Jessica; Sharma, Raven; Mann, Paul; Grasby, Stephen; Bezys, Ruth; Horgan, Briony; Londry, Kathleen; Rice, Melissa; Last, Bill; Last, Fawn; Badiou, Pascal; Goldsborough, Gordon; Bell, James

    2013-06-01

    This study explores the possible applications of a spring complex, East German Creek (EGC), Manitoba, Canada, as a terrestrial analogue for similar environments on Mars. Potential ancient spring deposits have been identified by Allen and Oehler (Allen, C.C., Oehler, D.Z. [2008]. Astrobiology 8, 1093-1112) in Vernal Crater, Arabia Terra, as well as in the intercrater plains of Terra Sirenum by Wray et al. (Wray et al. [2011]. J. Geophys. Res., 116, 1-41). EGC can provide guidance in the search for fossil spring deposits on Mars by using comparative mineralogy to contrast mineral identification from field studies to that available from remote sensing instruments such as the CRISM instrument aboard the Mars Reconnaissance Orbiter. The formation processes of EGC are also useful for finding spring-like environments on Mars. A variety of techniques were employed (X-ray diffractometry, reflectance spectra, water chemistry analysis) to analyze mineralogical changes in spring water precipitates with distance from the main springs at EGC, which were compared with concentrations of dissolved species in outflow water. Biosignatures in outflow stream sediments as well as the effect of surficial Fe oxyhydroxide coatings on the detection of underlying carbonate absorption features have also been spectrally characterized. Halite is the main mineral precipitated at EGC, followed by gypsum, and calcite. The presence of gypsum is readily detected in surficial precipitate spectra while halite does not have a diagnostic spectral signature in the 0.35-2.5 μm region. An absorption feature indicative of chlorophyll a is present in stream sediment spectra from most sampling stations and on outwash plain sediments. Carbonates appear to be spectrally detectable through a coating of ferric minerals, such as goethite by a characteristic absorption band near 2.3 μm. We attempted to detect significant spectral changes over an area of potential spring features in Vernal Crater on Mars using

  16. Update: Saudi Arabia.

    ERIC Educational Resources Information Center

    McGregor, Joy; Nydell, Margaret

    A guide for persons planning on living in or relocating to Saudi Arabia for extended periods of time, this book features information on such topics as entry requirements, transportation, money matters, housing, schools, and insurance. The guide's contents include the following sections: (1) an overview; (2) before leaving; (3) on arrival; (4)…

  17. Absolute Measurements of Methane on Mars

    NASA Astrophysics Data System (ADS)

    Mumma, M. J.; Villanueva, G. L.; Novak, R. E.

    2009-12-01

    On Mars, methane has been sought for nearly 40 years because of its potential biological significance, but it was detected only recently [1-5]. Its distribution on the planet is found to be patchy and to vary with time [1,2,4,5], suggesting that methane is released from the subsurface in localized areas, and is then rapidly destroyed [1,6]. To date, we have detected four spectral lines of the CH4 ν3 band near 3.3 µm, along with H2O and HDO [1,5,7]. Our observational campaign resumed in August 2009, now using CRIRES/VLT along with CSHELL/NASA-IRTF and NIRSPEC/Keck. Our study of methane on Mars now extends over four Mars years, sampling a wide range of seasons (Ls) with significant spatial coverage. For a typical observation, the spectrometer's long entrance slit is held to the central meridian of Mars while spectra are taken sequentially in time. For each snapshot in time, spectra are acquired simultaneously at contiguous positions along the entire slit length, sampling latitudinally resolved spatial footprints on the planet (35 footprints along the N-S meridian, when Mars is 7 arc-sec in diameter). Successive longitudes are presented as the planet rotates, and the combination then permits partial mapping of the planet. In Northern summer 2003, methane was notably enriched over several localized areas: A (East of Arabia Terra, where water vapor is also greatly enriched), B1 (Nili Fossae), and B2 (southeast quadrant of Syrtis Major) [1,5]. The combined plume contained ~19,000 metric tons of methane, and the estimated source strength (≥ 0.6 kilogram per second) was comparable to that of the massive hydrocarbon seep at Coal Oil Point in Santa Barbara, California. By vernal equinox about one-half the released methane had been lost. When averaged over latitude and season, spectral data from Mars Express also imply an enhancement in methane in this longitude range [4]. The most compelling results from these searches are: 1) the unambiguous detection of multiple

  18. The seasonal cycle of water vapour on Mars from assimilation of Thermal Emission Spectrometer data

    NASA Astrophysics Data System (ADS)

    Steele, Liam J.; Lewis, Stephen R.; Patel, Manish R.; Montmessin, Franck; Forget, François; Smith, Michael D.

    2014-07-01

    We present for the first time an assimilation of Thermal Emission Spectrometer (TES) water vapour column data into a Mars global climate model (MGCM). We discuss the seasonal cycle of water vapour, the processes responsible for the observed water vapour distribution, and the cross-hemispheric water transport. The assimilation scheme is shown to be robust in producing consistent reanalyses, and the global water vapour column error is reduced to around 2-4 pr μm depending on season. Wave activity is shown to play an important role in the water vapour distribution, with topographically steered flows around the Hellas and Argyre basins acting to increase transport in these regions in all seasons. At high northern latitudes, zonal wavenumber 1 and 2 stationary waves during northern summer are responsible for spreading the sublimed water vapour away from the pole. Transport by the zonal wavenumber 2 waves occurs primarily to the west of Tharsis and Arabia Terra and, combined with the effects of western boundary currents, this leads to peak water vapour column abundances here as observed by numerous spacecraft. A net transport of water to the northern hemisphere over the course of one Mars year is calculated, primarily because of the large northwards flux of water vapour which occurs during the local dust storm around LS=240-260°. Finally, outlying frost deposits that surround the north polar cap are shown to be important in creating the peak water vapour column abundances observed during northern summer.

  19. The Seasonal Cycle of Water Vapour on Mars from Assimilation of Thermal Emission Spectrometer Data

    NASA Technical Reports Server (NTRS)

    Steele, Liam J.; Lewis, Stephen R.; Patel, Manish R.; Montmessin, Franck; Forget, Francois; Smith, Michael D.

    2014-01-01

    We present for the first time an assimilation of Thermal Emission Spectrometer (TES) water vapour column data into a Mars global climate model (MGCM). We discuss the seasonal cycle of water vapour, the processes responsible for the observed water vapour distribution, and the cross-hemispheric water transport. The assimilation scheme is shown to be robust in producing consistent reanalyses, and the global water vapour column error is reduced to around 2-4 pr micron depending on season. Wave activity is shown to play an important role in the water vapour distribution, with topographically steered flows around the Hellas and Argyre basins acting to increase transport in these regions in all seasons. At high northern latitudes, zonal wavenumber 1 and 2 stationary waves during northern summer are responsible for spreading the sublimed water vapour away from the pole. Transport by the zonal wavenumber 2 waves occurs primarily to the west of Tharsis and Arabia Terra and, combined with the effects of western boundary currents, this leads to peak water vapour column abundances here as observed by numerous spacecraft. A net transport of water to the northern hemisphere over the course of one Mars year is calculated, primarily because of the large northwards flux of water vapour which occurs during the local dust storm around L(sub S) = 240-260deg. Finally, outlying frost deposits that surround the north polar cap are shown to be important in creating the peak water vapour column abundances observed during northern summer.

  20. Gravitational Effects of Flooding and Filling of Impact Basins on Mars

    NASA Technical Reports Server (NTRS)

    Smith, David E.; Zuber, Maria T.

    2004-01-01

    The presence of large impact basins and the low northern plains that might have contained ice or liquid water at an earlier stage of Mars evolution suggests that the global gravity field could have been different in the distant past than it is today. In addition, any significant change in the distribution of mass affects the moments of inertia and consequently and could conceivably change the position of the pole and the length of day. Similar effects could have been produced by large erosional processes, such as the removal of crustal material from the Arabia Terra region and subsequent re-deposition in the Chryse region of the northern plains. We have endeavored to estimate the magnitudes of material that might have been involved in these processes and their possible effect on the gravity and dynamics of Mars. We have used present-day topography and gravity field as a starting point, recognizing that both the result of the processes that we are trying to study rather than the state at the times of interest.

  1. SUV Tracks On Mars? The 'Devil' is in the Details

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Sport Utility Vehicles (SUVs) on Mars? Imagine the MOC imaging team's surprise on the morning of April 27, 1998, as the latest images came in from the 'Red Planet.'

    A picture taken by the camera on Mars Global Surveyor just one day earlier showed several thin, dark lines that--at first glance--looked like pathways blazed by off-road sport utility vehicles. Who's been driving around on Mars?

    The MOC image in question (#26403), seen here at full resolution of 13.8 meters (45 feet) per pixel, was obtained around 10:22 a.m. PDT on April 26, 1998, during Mars Global Surveyor's 264th orbit. North is approximately up, illumination is from the lower right. Located in eastern Arabia Terra near 16.5o N latitude, 311.4o W longitude, the image showed a number of natural features--small craters formed by meteor impact, several buttes and mesas left by erosion of the surrounding terrain, small dunes and drifts, and a mantle of dust that varies in thickness from place to place. But the new picture also showed two dark lines--each varying in width up to about 15 meters (49 feet)--that extended several kilometers/miles across the image.

    Lines like these have been seen before on Mars. They are most likely the result of dust devils--columnar vortices of wind that move across the landscape, pick up dust, and look somewhat like miniature tornadoes. Dust devils are a common occurrence in dry and desert landscapes on Earth as well as Mars. They form when the ground heats up during the day, warming the air immediately above the surface. As pockets of warm air rise and interfere with one another, they create horizontal pressure variations that, combined with other meteorological winds, cause the upward moving air to spin (the direction of the spin is controlled by the same Coriolis forces that cause terrestrial hurricanes to spin in specific directions). As the spinning column of air moves across the surface, it occasionally encounters dust on the surface, which it can suck upward

  2. Major water-related episodes on the lowlands of Mars

    NASA Astrophysics Data System (ADS)

    Fairén, A. G.; Dohm, J. M.; Baker, V. R.

    2003-04-01

    in Arabia Terra, where the initial shoreline might have been as far south as Sinus Meridani (Edgett and Parker, 1997), forming an almost equipotential line (total elevation differences are ˜2 km) that we name Contact 0, which is also consistent with the location of the boundary in crustal thickness dichotomy, as deduced from topography and gravity data (Zuber et al., 2000), and with the locus of debouch of almost every valley network in Arabia (Edgett and Parker, 1997; Carr, 2002); a Late Hesperian sea, which would have extended over the deeper areas in the lowlands inset within the boundary of the first great ocean, and so portrayed by Contact 2; and a number of widely distributed minor lakes that may represent a reduced Late Hesperian sea, or ponded waters in the deepest reaches of the northern plains related to minor Tharsis (e.g., Anderson et al., 2001) and Elysium (Skinner and Tanaka, 2001) induced Amazonian flooding. Possible biologic evolution throughout the resulting different climatic and hydrologic conditions would account for very distinct metabolic pathways for hypothesized organisms capable of surviving and perhaps evolving in each aqueous environment, those that existed in the dry and cold periods between the flood inundations, and those organisms that could survive both extremes. Terrestrial microbiota, chemolithotrophic and heterotrophic bacteria, provide exciting analogues for such potential extremophile existence in Mars, especially where long-lived, magmatic-driven hydrothermal activity is indicated (Farmer and Des Marais, 1999). Such Martian environments and related materials and life forms may have been excavated to the surface by catastrophic outflows making targets readily available for sampling and in-deep analyses. References Anderson, R. C. et al.: Primary centers and secondary concentrations of tectonic activity through time in western hemisphere of Mars. J. Geophys. Res. 106, 20 563--20 585, 2001. Baker, V.R., et al.: Ancient oceans, ice

  3. Irrigated Agriculture, Saudi Arabia

    NASA Technical Reports Server (NTRS)

    1990-01-01

    In Saudi Arabia, center-pivot, swing-arm irrigated agriculture complexes such as the one imaged at Jabal Tuwayq (20.5N, 45.0 E) extract deep fossil water reserves to achieve food crop production self sufficiency in this desert environment. The significance of the Saudi expanded irrigated agriculture is that the depletion of this finite water resource is a short term solution to a long term need that will still exist when the water has been extracted.

  4. Science Writers' Guide to TERRA

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The launch of NASA's Terra spacecraft marks a new era of comprehensive monitoring of the Earth's atmosphere, oceans, and continents from a single space-based platform. Data from the five Terra instruments will create continuous, long-term records of the state of the land, oceans, and atmosphere. Together with data from other satellite systems launched by NASA and other countries, Terra will inaugurate a new self-consistent data record that will be gathered over the next 15 years. The science objectives of NASAs Earth Observing System (EOS) program are to provide global observations and scientific understanding of land cover change and global productivity, climate variability and change, natural hazards, and atmospheric ozone. Observations by the Terra instruments will: provide the first global and seasonal measurements of the Earth system, including such critical functions as biological productivity of the land and oceans, snow and ice, surface temperature, clouds, water vapor, and land cover; improve our ability to detect human impacts on the Earth system and climate, identify the "fingerprint" of human activity on climate, and predict climate change by using the new global observations in climate models; help develop technologies for disaster prediction, characterization, and risk reduction from wildfires, volcanoes, floods, and droughts, and start long-term monitoring of global climate change and environmental change.

  5. Relative Ages of the Highlands, Lowlands, and Transition Zone Along a Portion of the Mars Crustal Dichotomy from Densities of Visible and Buried Impact Craters

    NASA Technical Reports Server (NTRS)

    DeSoto, G. E.; Frey, H. V.

    2005-01-01

    Understanding the fundamental age relationships of the different parts of the Mars Crustal Dichotomy is essential to fully understanding the events that shaped the early history and formation of the surface of Mars. A dominant question is what are the true relative ages of the Northern Lowlands and the Southern Highlands? Using MOLA data from the Mars Global Surveyor and Viking visual images, a dataset of both buried and visible crater diameters was created over a nine million sq km study area of a section of the dichotomy boundary stretching from Arabia Terra to Utopia Planitia. Cumulative frequency plots on a log-log scale were used to determine the relative ages for the Highlands, the Lowlands, and the Transition Zone, separately for the visible, the buried and the combined total (visible+ buried) populations. We find the overall Highland crater population in this area is slightly older than the Lowlands, consistent with previous global studies, but the Lowlands and Transition Zone are also very old and formed at roughly the same time. It appears that the formation of the Lowlands in this region formed contemporaneously with a large-scale resurfacing event in the Highlands, perhaps caused by the process responsible for the Lowland formation.

  6. Lunar and Planetary Science XXXV: Mars Geophysics

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The titles in this section include: 1) Distribution of Large Visible and Buried Impact Basins on Mars: Comparison with Free-Air Gravity, Crustal Thickness, and Magnetization Models; 2) The Early Thermal and Magnetic State of Terra Cimmeria, Southern Highlands of Mars; 3) Compatible Vector Components of the Magnetic Field of the Martian Crust; 4) Vertical Extrapolation of Mars Magnetic Potentials; 5) Rock Magnetic Fields Shield the Surface of Mars from Harmful Radiation; 6) Loading-induced Stresses near the Martian Hemispheric Dichotomy Boundary; 7) Growth of the Hemispheric Dichotomy and the Cessation of Plate Tectonics on Mars; 8) A Look at the Interior of Mars; 9) Uncertainties on Mars Interior Parameters Deduced from Orientation Parameters Using Different Radio-Links: Analytical Simulations; 10) Refinement of Phobos Ephemeris Using Mars Orbiter Laser Altimetry Radiometry.

  7. Health Education in Saudi Arabia

    PubMed Central

    Al-Hashem, Anwar

    2016-01-01

    This article provides a historical overview of the evolution of health education in Saudi Arabia. It outlines milestones in the development of the health education profession and traces the roles of various health sectors and their achievements in the health education field. Additionally, this review seeks to describe the status of health education professionals in Saudi Arabia. PMID:27606106

  8. TerraSAR-X mission

    NASA Astrophysics Data System (ADS)

    Werninghaus, Rolf

    2004-01-01

    The TerraSAR-X is a German national SAR- satellite system for scientific and commercial applications. It is the continuation of the scientifically and technologically successful radar missions X-SAR (1994) and SRTM (2000) and will bring the national technology developments DESA and TOPAS into operational use. The space segment of TerraSAR-X is an advanced high-resolution X-Band radar satellite. The system design is based on a sound market analysis performed by Infoterra. The TerraSAR-X features an advanced high-resolution X-Band Synthetic Aperture Radar based on the active phased array technology which allows the operation in Spotlight-, Stripmap- and ScanSAR Mode with various polarizations. It combines the ability to acquire high resolution images for detailed analysis as well as wide swath images for overview applications. In addition, experimental modes like the Dual Receive Antenna Mode allow for full-polarimetric imaging as well as along track interferometry, i.e. moving target identification. The Ground Segment is optimized for flexible response to (scientific and commercial) User requests and fast image product turn-around times. The TerraSAR-X mission will serve two main goals. The first goal is to provide the strongly supportive scientific community with multi-mode X-Band SAR data. The broad spectrum of scientific application areas include Hydrology, Geology, Climatology, Oceanography, Environmental Monitoring and Disaster Monitoring as well as Cartography (DEM Generation) and Interferometry. The second goal is the establishment of a commercial EO-market in Europe which is driven by Infoterra. The commercial goal is the development of a sustainable EO-business so that the e.g. follow-on systems can be completely financed by industry from the profit. Due to its commercial potential, the TerraSAR-X project will be implemented based on a public-private partnership with the Astrium GmbH. This paper will describe first the mission objectives as well as the

  9. Intimations of water on Mars.

    PubMed

    2000-08-01

    This photo essay contains images of Mars that propose evidence of the possible present or past existence of liquid water on Mars. Images were taken by the Mars Global Surveyor Mars Orbiter Camera. Images presented include: Polar Wall Pit region, consisting of gully landforms possibly caused by seepage and runoff of liquid water; Noachis Terra region, an area of gullies eroded into the wall of a meteor impact crater, where channels and related debris are seen, possibly formed by seepage, runoff, and debris flow; two images of Gorgonum Chaos region, one a series of troughs and layers of gullies and the other of gullies in a specific layer forming an alcove similar to an aquifer; Sirenum Fossae/Gorgonum Chaos mosaic of two images from this region of the southern hemisphere of Mars, showing 20 different channels coming down from a trough and their associated debris fans. Images and their enhancements are from NASA/JPL/Malin Space Science System. PMID:11543294

  10. Terra firma-forme dermatosis.

    PubMed

    Oztürk, Ferdi; Kocabaş, Engin; Ertan, Pelin; Ermertcan, Aylin Türel

    2010-12-01

    Terra firma-forme dermatosis (TFFD) is an uncommon disorder of keratinization with an unknown etiology in which patients present with dirt-like lesions that are resistant to washing. A 6-year old girl presented with the complaint of an asymptomatic brownish black dirt-like eruption on her body. Her parents reported no response to washing with soap and water. Dermatologic examination revealed brown hyperpigmented patches on the trunk and abdominal region. TFFD was suspected, and isopropyl alcohol was applied to the patient's lesions. All lesions completely disappeared after rubbing with alcohol. Terra firma-forme dermatosis is a relatively recently described entity that is much more common than might be expected when surveying the medical literature. With the very few reports found in the literature about TFFD, we believe that an increased awareness of this entity among primary care physicians would help decrease unnecessary worries or medical procedures, since TFFD lesions simply resolve by rubbing with isopropyl alcohol. PMID:20684734

  11. The global distribution of near-surface hydrogen on Mars

    SciTech Connect

    Feldman, W. C.; Prettyman, T. H.; Maurice, S.; Bish, D. L.; Vaniman, D. T.; Squyres, Steven W.; Boynton, W. V.; Elphic, R. C.; Funsten, H. O.; Lawrence, David J. ,; Tokar, R. L.; Moore, K. R.

    2004-01-01

    Odyssey neutron observations also revealed a near equatorial hydrogen reservoir that maximizes in Arabia Terra and its antipode. Initial quantitative estimates of hydrogen abundances in these investigations were normalized to an assumed 1% H{sub 2}O content by mass for the Viking 1 landing site. However, a recent analysis of the seasonal variation of the CO{sub 2} frost cover at the north pole has allowed an independent absolute calibration of the three neutron energy bands measured using the NS aboard Mars Odyssey. This calibration allows a reinterpretation of neutron fluxes measured globally to provide a lower bound of the hydrogen abundance within about 1 m of the Martian surface. A determination of true hydrogen abundances requires knowledge of the stratigraphy of hydrogen-bearing layers because the presence of an overlying relatively desiccated layer would mask enhanced abundances of a lower layer.

  12. Variations in Crustal Structure, Lithospheric Flexural Strength, and Isostatic Compensation Mechanisms of Mars

    NASA Astrophysics Data System (ADS)

    Ding, M.; Lin, J.; Zuber, M. T.

    2014-12-01

    We analyze gravity and topography of Mars to investigate the spatial variations in crustal thickness, lithospheric strength, and mechanisms of support of prominent topographic features on Mars. The latest gravity model JGMRO110c (released in 2012) from the Mars Reconnaissance Orbiter mission has a spatial block size resolution of ~97 km (corresponding to degree-110), enabling us to resolve crustal structures at higher spatial resolution than those determined from previous degree-80 and 85 gravity models [Zuber et al., 2000; McGovern et al., 2002, 2004; Neumann et al., 2004; Belleguic et al., 2005]. Using the latest gravity data, we first inverted for a new version of crustal thickness model of Mars assuming homogeneous crust and mantle densities of 2.9 and 3.5 g/cm3. We calculated "isostatic" topography for the Airy local isostatic compensation mechanism, and "non-isostatic" topography after removing the isostatic part. We find that about 92% of the Martian surface is in relatively isostatic state, indicating either relatively small lithospheric strength and/or small vertical loading. Relatively isostatic regions include the hemispheric dichotomy, Hellas and Argyre Planitia, Noachis and Arabia Terra, and Terra Cimmeria. In contrast, regions with significant amount of non-isostatic topography include the Olympus, Ascraeus, Arsia, Pavonis, Alba, and Elysium Mons, Isidis Planitia and Valles Marineris. Their relatively large "non-isostatc topography" implies relatively strong lithospheric strength and large vertical loading. Spectral analysis of the admittance and correlation relationship between gravity and topography were conducted for the non-isostatic regions using the localized spectra method [Wieczorek and Simons, 2005, 2007] and thin-shell lithospheric flexural approximation [Forsyth, 1985; McGovern et al., 2002, 2004]. The best-fitting models reveal significant variations in the effective lithospheric thickness with the greatest values for the Olympus Mon

  13. Mars Ice Age, Simulated

    NASA Technical Reports Server (NTRS)

    2003-01-01

    December 17, 2003

    This simulated view shows Mars as it might have appeared during the height of a possible ice age in geologically recent time.

    Of all Solar System planets, Mars has the climate most like that of Earth. Both are sensitive to small changes in orbit and tilt. During a period about 2.1 million to 400,000 years ago, increased tilt of Mars' rotational axis caused increased solar heating at the poles. A new study using observations from NASA's Mars Global Surveyor and Mars Odyssey orbiters concludes that this polar warming caused mobilization of water vapor and dust into the atmosphere, and buildup of a surface deposit of ice and dust down to about 30 degrees latitude in both hemispheres. That is the equivalent of the southern Unites States or Saudi Arabia on Earth. Mars has been in an interglacial period characterized by less axial tilt for about the last 300,000 years. The ice-rich surface deposit has been degrading in the latitude zone of 30 degrees to 60 degrees as water-ice returns to the poles.

    In this illustration prepared for the December 18, 2003, cover of the journal Nature, the simulated surface deposit is superposed on a topography map based on altitude measurements by Global Surveyor and images from NASA's Viking orbiters of the 1970s.

    Mars Global Surveyor and Mars Odyssey are managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, for the NASA Office of Space Science, Washington.

  14. Roughness and near-surface density of Mars from SHARAD radar echoes

    NASA Astrophysics Data System (ADS)

    Campbell, Bruce A.; Putzig, Nathaniel E.; Carter, Lynn M.; Morgan, Gareth A.; Phillips, Roger. J.; Plaut, Jeffrey J.

    2013-03-01

    We present a technique for estimating Mars topographic roughness on horizontal scales from about 10 m to 100 m using Shallow Radar (SHARAD) sounding data. Our results offer a view of surface properties complementary to Mars Orbiter Laser Altimeter (MOLA) pulse-width or baseline roughness maps and can be compared to SHARAD peak-echo properties to infer deviations from the average near-surface density. Latitudinal averaging of SHARAD-derived roughness over Arabia and Noachis Terrae shows good agreement with MOLA-derived roughness and provides clear evidence for latitude-dependent mantling deposits previously inferred from image data. In northwestern Gordii Dorsum, we find that bulk density in at least the upper few meters is significantly lower than in other units of the Medusae Fossae Formation. We observe the same behavior indicative of low near-surface density in wind-eroded crater fill in the southern highlands. Combining surface-properties analysis, subsurface sounding, and high-resolution optical images, we show that the Pavonis Mons fan-shaped deposit differs significantly from lobate debris aprons which SHARAD has shown to be ice-cored. There are no internal radar reflections from the smooth-facies portion of the Pavonis Mons fan-shaped deposit, and we suggest that these deposits are either quite thin or have little dielectric (i.e., density) contrast with the underlying terrain. Future application of these techniques can identify other low-density units across Mars, assist in the mapping of regional volatile-rich mantling units, and provide new constraints on the physical properties of the polar layered terrain.

  15. Terra Nova Bay Polynya, Antarctica

    NASA Technical Reports Server (NTRS)

    2007-01-01

    In Terra Nova Bay, off the Scott Coast of Victoria Land, Antarctica, a large pocket of open water persists throughout most of the Southern Hemisphere winter, even while most of the rest of the Antarctic coastline is firmly embraced by the frozen Southern Ocean. This pocket of open water--a polynya--results from exceptionally strong winds that blow downslope from the Trans-Antarctic Mountains. These fierce katabatic winds drive the sea ice eastward. Since the dominant ice drift pattern in the area is northward, the Drygalski Ice Tongue prevents the bay from being re-populated with sea ice. This image of the Terra Nova Bay polynya was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite on October 16, 2007. Sea ice sits over the Ross Sea like a cracked and crumbling windshield. Blue-tinged glaciers flow down from the Trans-Antarctic Mountains. Although glaciers can appear blue because of melt water, they can also get that tint when the wind scours and polishes the ice surface. Given the strength of the katabatic winds along this part of the Antarctic coast, it is likely that the blue color of these glaciers is a result of their having been swept clean of snow. The large image has a spatial resolution (level of detail) of 250 meters per pixel.

  16. Geologic history and channeling episodes of the Chryse Planitia region of Mars

    NASA Astrophysics Data System (ADS)

    Rotto, Susan L.; Tanaka, Kenneth L.

    1991-06-01

    The study of the Chryse Planitia region of Mars is based on geologic mapping on a 1:5,000,000 scale shaded relief map. The map area includes Chryse and southern Acidalia Planitiae; the circum Chryse channels and chaotic terrains; Xanthe, southern Tempe, and western Arabia Terrae; Lunae Planum; and northeastern Valles Marineris. The aim of the study is twofold: (1) to obtain relative ages of the outflow channels by performing and compiling detailed stratigraphic analyses; and (2) to correlate channeling episodes with causative mechanisms (such as volcanism and tectonism) and resulting effects (such as climate change). The geologic history given based on this mapping, includes the documentation of a previously unproposed channeling episode in the region as well as the presently favored hypotheses concerning the nature and origin of the channeling events. It is concluded that the history of the Chryse region suggests that two major periods of tectonic activity resulted in two episodes of channeling in the highlands surrounding Chryse Planitia.

  17. Mars Through the Eye of HiRISE

    NASA Astrophysics Data System (ADS)

    McEwen, A. S.; Hirise, T.

    2007-05-01

    The High Resolution Imaging Science Experiment (HiRISE) has acquired more than 2 Tb of data in more than 1,000 images of Mars at resolutions as high as 25 cm/pixel in the 3 PM mapping orbit of Mars Reconnaissance Orbiter. Each image consists of data from up to 14 CCD detectors and could contain as many as 3 giga-pixels. Early results include (1) improved knowledge of the stratigraphy of the north polar layered deposits and the origin of the thick basal unit; (2) discovery that rocks are uniformly abundant in the Vastitas Borealis Formation covering the northern lowlands; (3) imaging of past landing sites has provided new insights and surprises about the nature of these surfaces; (4) fine layered deposits in Valles Marineris, Meridiani Planum, Arabia Terra and elsewhere are often cut by indurated and/or bleached joints and faults, most likely due to precipitation from fluids; (5) regions of Mars rich in phyllosilicate minerals [Murchie et al., submitted] are seen to consist of layered deposits with fine-scale fractures and polygons; (6) lava flows through Athabasca Valles were surprisingly thick flows that were deflated and drained, leaving behind a veneer of lava with abundant evidence for lava-water interactions; (7) stratigraphic studies reveal two major episodes of fluvial/lacustrine activity in Holden crater, and we've detected exposures of ancient megabreccia in the crater walls; (8) recent large (3-60 km) impact craters have created a range of apparently fluvially-modified landforms; (9) a small cluster of craters from a very recent impact event created a large (~2 km) wide blast zone with thousands of dust avalanches; (10) relatively bright deposits associated with very recent activities in gullies appear to consist of materials eroded from the crater slopes; (11) the south polar residual cap of CO2 has a range of newly-discovered morphologies that constrain models for landscape evolution; and(12) geysers or cold jets associated with sublimation of the

  18. First dinosaurs from Saudi Arabia.

    PubMed

    Kear, Benjamin P; Rich, Thomas H; Vickers-Rich, Patricia; Ali, Mohammed A; Al-Mufarreh, Yahya A; Matari, Adel H; Al-Massari, Abdu M; Nasser, Abdulaziz H; Attia, Yousry; Halawani, Mohammed A

    2013-01-01

    Dinosaur remains from the Arabian subcontinent are exceedingly rare, and those that have been documented manifest indeterminate affinities. Consequently the discovery of a small, but diagnostic, accumulation of elements from Campanian-Maastrichtian (~ 75 Ma) deposits in northwestern Saudi Arabia is significant because it constitutes the first taxonomically identifiable dinosaur material described from the Arabian Peninsula. The fossils include a series of possible lithostrotian titanosaur caudal vertebrae, and some isolated theropod marginal teeth that share unique character states and metric parameters (analyzed using multivariate statistical methods) with derived abelisaurids - this is the first justifiable example of a non-avian carnivorous dinosaur clade from Arabia. The recognition of titanosaurians and abelisaurids from Saudi Arabia extends the palaeogeographical range of these groups along the entire northern Gondwanan margin during the latest Cretaceous. Moreover, given the extreme paucity of coeval occurrences elsewhere, the Saudi Arabian fossils provide a tantalizing glimpse into dinosaurian assemblage diversity within the region. PMID:24386326

  19. First Dinosaurs from Saudi Arabia

    PubMed Central

    Kear, Benjamin P.; Rich, Thomas H.; Vickers-Rich, Patricia; Ali, Mohammed A.; Al-Mufarreh, Yahya A.; Matari, Adel H.; Al-Massari, Abdu M.; Nasser, Abdulaziz H.; Halawani, Mohammed A.

    2013-01-01

    Dinosaur remains from the Arabian subcontinent are exceedingly rare, and those that have been documented manifest indeterminate affinities. Consequently the discovery of a small, but diagnostic, accumulation of elements from Campanian-Maastrichtian (∼75 Ma) deposits in northwestern Saudi Arabia is significant because it constitutes the first taxonomically identifiable dinosaur material described from the Arabian Peninsula. The fossils include a series of possible lithostrotian titanosaur caudal vertebrae, and some isolated theropod marginal teeth that share unique character states and metric parameters (analyzed using multivariate statistical methods) with derived abelisaurids – this is the first justifiable example of a non-avian carnivorous dinosaur clade from Arabia. The recognition of titanosaurians and abelisaurids from Saudi Arabia extends the palaeogeographical range of these groups along the entire northern Gondwanan margin during the latest Cretaceous. Moreover, given the extreme paucity of coeval occurrences elsewhere, the Saudi Arabian fossils provide a tantalizing glimpse into dinosaurian assemblage diversity within the region. PMID:24386326

  20. Rub' al Khali, Arabia

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Rub' al Khali is one of the largest sand deserts in the world, encompassing most of the southern third of the Arabian Peninsula. It includes parts of Oman, United Arab Emirates, and Yemen. The desert covers 650,000 square kilometers, more than the area of France. Largely unexplored until recently, the desert is 1000 km long and 500 km wide. The first documented journeys made by Westerners were those of Bertram Thomas in 1931 and St. John Philby in 1932. With daytime temperatures reaching 55 degrees Celsius, and dunes taller than 330 meters, the desert may be one of the most forbidding places on Earth.

    The image was acquired December 2, 2005, covers an area of 54.8 x 61.9 km, and is located near 20.7 degrees north latitude, 53.6 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  1. Adult Education in Saudi Arabia.

    ERIC Educational Resources Information Center

    Griffin, Tim D.; Algren, Mark S.

    Religion pervades all aspects of Saudi Arabia, the conservative home of Islam, where the constitution is the Quran and law is interpreted by religious scholars. A formal adult basic education program was initiated in 1960. As part of the country's modernization since the early 1970s, the Saudi government has begun an enormous nation-building plan…

  2. Social Education in Saudi Arabia.

    ERIC Educational Resources Information Center

    Al-Jabr, Soliman M.

    1990-01-01

    Reveals some cultural aspects of Saudi Arabian Islamic society and the role social studies education plays in it. States that the National Council for the Social Studies in Saudia Arabia stipulates general social studies goals and allows teachers to make specific behavioral goals. Concludes that Saudi Arabian schools are becoming more modern. (GG)

  3. Tectonic implications of Mars crustal magnetism.

    PubMed

    Connerney, J E P; Acuña, M H; Ness, N F; Kletetschka, G; Mitchell, D L; Lin, R P; Reme, H

    2005-10-18

    Mars currently has no global magnetic field of internal origin but must have had one in the past, when the crust acquired intense magnetization, presumably by cooling in the presence of an Earth-like magnetic field (thermoremanent magnetization). A new map of the magnetic field of Mars, compiled by using measurements acquired at an approximately 400-km mapping altitude by the Mars Global Surveyor spacecraft, is presented here. The increased spatial resolution and sensitivity of this map provide new insight into the origin and evolution of the Mars crust. Variations in the crustal magnetic field appear in association with major faults, some previously identified in imagery and topography (Cerberus Rupes and Valles Marineris). Two parallel great faults are identified in Terra Meridiani by offset magnetic field contours. They appear similar to transform faults that occur in oceanic crust on Earth, and support the notion that the Mars crust formed during an early era of plate tectonics. PMID:16217034

  4. Tectonic implications of Mars crustal magnetism

    PubMed Central

    Connerney, J. E. P.; Acuña, M. H.; Ness, N. F.; Kletetschka, G.; Mitchell, D. L.; Lin, R. P.; Reme, H.

    2005-01-01

    Mars currently has no global magnetic field of internal origin but must have had one in the past, when the crust acquired intense magnetization, presumably by cooling in the presence of an Earth-like magnetic field (thermoremanent magnetization). A new map of the magnetic field of Mars, compiled by using measurements acquired at an ≈400-km mapping altitude by the Mars Global Surveyor spacecraft, is presented here. The increased spatial resolution and sensitivity of this map provide new insight into the origin and evolution of the Mars crust. Variations in the crustal magnetic field appear in association with major faults, some previously identified in imagery and topography (Cerberus Rupes and Valles Marineris). Two parallel great faults are identified in Terra Meridiani by offset magnetic field contours. They appear similar to transform faults that occur in oceanic crust on Earth, and support the notion that the Mars crust formed during an early era of plate tectonics. PMID:16217034

  5. DEMONSTRATION BULLETIN: TERRA KLEEN SOLVENT EXTRACTION TECHNOLOGY - TERRA-KLEEN RESPONSE GROUP, INC.

    EPA Science Inventory

    The Terra-Kleen Solvent Extraction Technology was developed by Terra-Kleen Response Group, Inc., to remove polychlorinated biphenyls (PCB) and other organic constituents from contaminated soil. This batch process system uses a proprietary solvent at ambient temperatures to treat ...

  6. The Earth Observing System Terra Mission

    NASA Technical Reports Server (NTRS)

    Kaufman, Yoram J.

    2000-01-01

    Langley's remarkable solar and lunar spectra collected from Mt. Whitney inspired Arrhenius to develop the first quantitative climate model in 1896. After the launch in Dec. 16 1999, NASA's Earth Observing AM Satellite (EOS-Terra) will repeat Langley's experiment, but for the entire planet, thus pioneering a wide array of calibrated spectral observations from space of the Earth System. Conceived in response to real environmental problems, EOS-Terra, in conjunction with other international satellite efforts, will fill a major gap in current efforts by providing quantitative global data sets with a resolution smaller than 1 km on the physical, chemical and biological elements of the earth system. Thus, like Langley's data, EOS-Terra can revolutionize climate research by inspiring a new generation of climate system models and enable us to assess the human impact on the environment. In the talk I shall review the historical perspective of the Terra mission and the key new elements of the mission. We expect to have some first images that demonstrate the most innovative capability from EOS Terra: MODIS - 1.37 microns cirrus channel; 250 m daily cover for clouds and vegetation change; 7 solar channels for land and aerosol; new fire channels; Chlorophyll fluorescence; MISR - 9 multi angle views of clouds and vegetation; MOPITT - Global CO maps and CH4 maps; ASTER - Thermal channels for geological studies with 15-90 m resolution.

  7. The Earth Observing System Terra Mission

    NASA Technical Reports Server (NTRS)

    Kaufman, Yoram J.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Langley's remarkable solar and lunar spectra collected from Mt. Whitney inspired Arrhenius to develop the first quantitative climate model in 1896. After the launch in Dec. 16 1999, NASA's Earth Observing AM Satellite (EOS-Terra) will repeat Langley's experiment, but for the entire planet, thus pioneering a wide array of calibrated spectral observations from space of the Earth System. Conceived in response to real environmental problems, EOS-Terra, in conjunction with other international satellite efforts, will fill a major gap in current efforts by providing quantitative global data sets with a resolution better than 1 km on the physical, chemical and biological elements of the earth system. Thus, like Langley's data, EOS-Terra can revolutionize climate research by inspiring a new generation of climate system models and enable us to assess the human impact on the environment. In the talk I shall review the historical perspective of the Terra mission and the key new elements of the mission. We expect to have first images that demonstrate the most innovative capability from EOS Terra 5 instruments: MODIS - 1.37 micron cirrus cloud channel; 250m daily coverage for clouds and vegetation change; 7 solar channels for land and aerosol studies; new fire channels; Chlorophyll fluorescence; MISR - first 9 multi angle views of clouds and vegetation; MOPITT - first global CO maps and C114 maps; ASTER - Thermal channels for geological studies with 15-90 m resolution.

  8. Terra - the Earth Observing System flagship observatory

    NASA Astrophysics Data System (ADS)

    Thome, K. J.

    2013-12-01

    The Terra platform enters its teenage years with an array of accomplishments but also with the potential to do much more. Efforts continue to extend the Terra data record to build upon its array of accomplishments and make its data more valuable by creating a record length that allows examination of inter annual variability, observe trends on the decadal scale, and gather statistics relevant to the define climate metrics. Continued data from Terra's complementary instruments will play a key role in creating the data record needed for scientists to develop an understanding of our climate system. Terra's suite of instruments: ASTER (contributed by the Japanese Ministry of Economy and Trade and Industry with a JPL-led US Science Team), CERES (NASA LaRC - PI), MISR (JPL - PI), MODIS (NASA GSFC), and MOPITT (sponsored by Canadian Space Agency with NCAR-led Science Team) are providing an unprecedented 81 core data products. The annual demand for Terra data remains with >120 million files distributed in 2011 and >157 million in 2012. More than 1,100 peer-reviewed publications appeared in 2012 using Terra data bringing the lifetime total >7,600. Citation numbers of 21,000 for 2012 and over 100,000 for the mission's lifetime. The broad range of products enable the community to provide answers to the overarching question, 'How is the Earth changing and what are the consequences for life on Earth?' Terra continues to provide data that: (1) Extend the baseline of morning-orbit collections; (2) Enable comparison of measurements acquired from past high-impact events; (3) Add value to recently-launched and soon-to-be launched missions, and upcoming field programs. Terra data continue to support monitoring and relief efforts for natural and man-made disasters that involve U.S. interests. Terra also contributes to Applications Focus Areas supporting the U.S. National Objectives for agriculture, air quality, climate, disaster management, ecological forecasting, public health, water

  9. DETAIL OF ORNAMENTAL TERRA COTTA FRIEZE ABOVE GROUND FLOOR AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF ORNAMENTAL TERRA COTTA FRIEZE ABOVE GROUND FLOOR AND TYPICAL TERRA COTTA WINDOW SILL. CORNER OF CLAY AND 15TH STREETS - John Breuner & Company Building, 1515 Clay Street, Oakland, Alameda County, CA

  10. Scaling the Pipe: NASA EOS Terra Data Systems at 10

    NASA Technical Reports Server (NTRS)

    Wolfe, Robert E.; Ramapriyan, Hampapuram K.

    2010-01-01

    Standard products from the five sensors on NASA's Earth Observing System's (EOS) Terra satellite are being used world-wide for earth science research and applications. This paper describes the evolution of the Terra data systems over the last decade in which the distributed systems that produce, archive and distribute high quality Terra data products were scaled by two orders of magnitude.

  11. Health Education in Saudi Arabia: Historical overview.

    PubMed

    Al-Hashem, Anwar

    2016-08-01

    This article provides a historical overview of the evolution of health education in Saudi Arabia. It outlines milestones in the development of the health education profession and traces the roles of various health sectors and their achievements in the health education field. Additionally, this review seeks to describe the status of health education professionals in Saudi Arabia. PMID:27606106

  12. Development of Higher Education in Saudi Arabia.

    ERIC Educational Resources Information Center

    Saleh, Mahmoud Abdullah

    1986-01-01

    The history of higher education in Saudi Arabia is outlined, especially as it relates to Islamic religion and educational philosophy, and its rapid growth is chronicled. These aspects are examined: Saudi students studying abroad, foreign students in Saudi Arabia, women's education, the Ministry of Higher Education's role, and financing. (MSE)

  13. Connecting Students across Universities in Saudi Arabia

    ERIC Educational Resources Information Center

    Al-Jarf, Reima Sado

    2005-01-01

    The present study reports results of an experiment in which the author and her students at King Saud University (KSU) in Riyadh, Saudi Arabia shared an online grammar course with a professor and his students at Umm Al-Qura University (UQU) in Makkah, Saudi Arabia using www.makkahelearning.net. The experiment proved to be a total failure. Factors…

  14. ES4 Terra-Xtrk Ed3

    Atmospheric Science Data Center

    2016-06-08

    ... Order:  Reverb   Reverb Tutorial Order Data:  Reverb:  Order Data Guide Documents:  ... for Terra and Aqua; Edition2 for TRMM) are approved for science publications.  Additional Info:  b SCAR-B ...

  15. Mars Landscapes

    NASA Video Gallery

    Spacecraft have studied the Martian surface for decades, giving Earthlings insights into the history, climate and geology of our nearest neighbor, Mars. These images are from "Mars Landscapes," a v...

  16. Terra Populus and DataNet Collaboration

    NASA Astrophysics Data System (ADS)

    Kugler, T.; Ruggles, S.; Fitch, C. A.; Clark, P. D.; Sobek, M.; Van Riper, D.

    2012-12-01

    Terra Populus, part of NSF's new DataNet initiative, is developing organizational and technical infrastructure to integrate, preserve, and disseminate data describing changes in the human population and environment over time. Terra Populus will incorporate large microdata and aggregate census datasets from the United States and around the world, as well as land use, land cover, climate and other environmental datasets. These data are widely dispersed, exist in a variety of data structures, have incompatible or inadequate metadata, and have incompatible geographic identifiers. Terra Populus is developing methods of integrating data from different domains and translating across data structures based on spatio-temporal linkages among data contents. The new infrastructure will enable researchers to identify and merge data from heterogeneous sources to study the relationships between human behavior and the natural world. Terra Populus will partner with data archives, data producers, and data users to create a sustainable international organization that will guarantee preservation and access over multiple decades. Terra Populus is also collaborating with the other projects in the DataNet initiative - DataONE, the DataNet Federation Consortium (DFC) and Sustainable Environment-Actionable Data (SEAD). Taken together, the four projects address aspects of the entire data lifecycle, including planning, collection, documentation, discovery, integration, curation, preservation, and collaboration; and encompass a wide range of disciplines including earth sciences, ecology, social sciences, hydrology, oceanography, and engineering. The four projects are pursuing activities to share data, tools, and expertise between pairs of projects as well as collaborating across the DataNet program on issues of cyberinfrastructure and community engagement. Topics to be addressed through program-wide collaboration include technical, organizational, and financial sustainability; semantic

  17. Terra in K-16 formal education settings

    NASA Astrophysics Data System (ADS)

    Chambers, L. H.; Fischer, J. D.; Lewis, P. M.; Moore, S. W.; Oots, P. C.; Rogerson, T. M.; Hitke, K. M.; Riebeek, H.

    2009-12-01

    Since it began, the Terra mission has had an active presence in formal education at the K-16 level. This educational presence was provided through the S’COOL project for the first five years of the mission, joined by the MY NASA DATA project for the second five years. The Students’ Cloud Observations On-Line (S’COOL) Project, begun in 1997 under the auspices of the Clouds and the Earth’s Radiant Energy System (CERES) project, seeks to motivate students across the entire K-12 spectrum to learn science basics and how they tie in to a larger picture. Beginning early on, college level participants have also participated in the project, both in science classes and in science education coursework. The project uses the connection to an on-going NASA science investigation as a powerful motivator for student observations, analysis and learning, and has reached around the globe as shown in the world map. This poster will review the impact that Terra, through S’COOL, has made in formal education over the last decade. The MY NASA DATA Project began in 2004 under the NASA Research, Education and Applications Solutions Network (REASoN). A 5-year REASoN grant enabled the creation of an extensive website which wraps easily accessible Earth science data - including Terra parameters from CERES (involving MODIS data fusion), MISR, and MOPITT (an example for carbon monoxide is given in the graph, with dark areas indicating high CO levels) - with explanatory material written at the middle school level, and an extensive collection of peer-reviewed lesson plans. The MY NASA DATA site has a rapidly growing user-base and was recently adopted by a number of NASA Earth Science missions, in addition to Terra, as a formal education arm of their Education and Public Outreach efforts. This poster will summarize the contributions that Terra, through MY NASA DATA, has made to formal education since 2004.

  18. Euripus Mons - Landform Evolution and Climate Constraints in Promethei Terra

    NASA Astrophysics Data System (ADS)

    van Gasselt, Stephan; Kim, Jungrack; Baik, Hyun-Seob

    2016-04-01

    The Promethei Terra region of Mars exhibits a variety of geomorphic landforms indicative of ice-assisted creep of debris and ice, similar to features and processes found at the Martian dichotomy boundary in Deuteronilus, Protonilus and Nilosyrtis Mensae. Despite only little doubt about the fact that ice played an integral role in the formation of these features, it is still disputed if these features were formed by glacial processes, requiring precipitation of ice and snow and exhibiting glacial deformation and basal sliding, or if these landforms are a product of periglacial denudation and subject to different deformation regimes. As information about past climate conditions on Mars is sparse, the proper assessment of landform types today allows to put constraints on their environmental conditions in the past. Due to limited knowledge about the internal physical and thermal structure of these landforms, it remains impossible to unambiguously determine their origin [1]. A variety of geomorphic and model-based indicators need to be taken into account when putting constraints on their history and when trying to reconstruct their evolution. For selected features on Mars it has been shown by SHARAD radar observations that the ice content might be relatively high [2], and that some of them might be composed of pure ice, protected from sublimation by a thin debris cover. One of such examples, Euripus Mons, is a 80 km remnant feature with an associated circumferential talus deposit that shows indicators for deformation by downslope movement, i.e. debris apron morphology. Recent modelling assuming glacial deformation helped to reconstruct some internal structural properties [3]. Despite these attempts, Euripus Mons shows clear geomorphic signatures of classical periglacial denudation which do not fit into the concept of glacial-only evolution. Denudation rates as well as ages are similar to those reported from other locations on Mars for which hyperarid climate conditions

  19. First Self-Consistent, Two-Layer Model of Near-Surface Water-Equivalent-Hydrogen on Mars

    NASA Astrophysics Data System (ADS)

    Feldman, W. C.; Pathare, A.; Prettyman, T. H.; Maurice, S.

    2015-12-01

    This study uses 9.5 years of Mars Odyssey Neutron Spectrometer (MONS) data [1]. We have used the epithermal and fast neutron count rates to determine the water-equivalent-hydrogen (WEH) content of an upper layer, Wup, having thickness D. The "crossover" technique we utilized is an improvement over previous work [2,3]. We then used Monte Carlo simulated grids of epithermal and thermal count rates spanning Wup = 1% to 15% [4] to determine the WEH content, Wdn, of a semi-infinite lower layer buried at depth, D. We also advance upon previous work by using improved deconvolution methods to reduce spatial blurring in fast and epithermal maps [5]. The resultant count-rates were digitized into a 2°x2°cylindrical grid for all WEH computations. Two sets of WEH maps will be shown. The first uses the one-layer model developed initially by Feldman et al. [6]. Comparison of the undeconvolved and deconvolved versions clearly illustrates the improvement obtained by deconvolution. We will also present the full two layer maps of Wup, Wdn, and D for the deconvolved data sets, which show: 1) contrary to our previous preliminary mapping [3], the fresh icy mid-latitude craters identified by [7] are NOT exclusively found in regions with average Wdn values that exceed the pore-filling threshold for regolith ice; 2) a maximum Wdn of about 80% by weight at the Phoenix site; 3) an isolated Wdn maximum just east of Gale crater that is centered on Aeolis Mensae; 4) a resolved Wdn maximum that overlays the Orsen Wells crater on Xanthe Terra; 5) Wdn local maxima that hug the western flanks of Olympus Mons and Elysium Mons, and 6) several Wdn maxima that cover Arabia Terra. We will present and interpret regional maps of all of these features. Refs: [1] Maurice et al. JGR, 2011; [2] Feldman et al. JGR, 2011; [3] Pathare et al. 8th Mars Conf., 2014; [4] Prettyman et al. JGR, 2004 [5] Prettyman et al. JGR, 2009; [6] Feldman et al. JGR, 2004; [7] Dundas et al. JGR, 2014.

  20. Central Saudi Arabia, Persian Gulf

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This panoramic view of Central Saudi Arabia and the Persian Gulf (28.0N, 47.0E) dramatically illustrates the stark beauty of the deserts. Riyadh, the capital city, lies in the foreground, with the Persian Gulf in the middle and Iran in the background. The coastal oil terminals of Al Hufuf and Ad Dammam are also visible. Black smudges of soot from the oil fires set during the Gulf War can be seen on the sands to the north and south of Kuwait City.

  1. Monitoring on Xi'an ground fissures deformation with TerraSAR-X data

    USGS Publications Warehouse

    Zhao, C.; Zhang, Q.; Zhu, W.; Lu, Zhiming

    2012-01-01

    Owing to the fine resolution of TerraSAR-X data provided since 2007, this paper applied 6 TerraSAR data (strip mode) during 3rd Dec. 2009 to 23rd Mar. 2010 to detect and monitor the active fissures over Xi'an region. Three themes have been designed for high precision detection and monitoring of Xi'an-Chang'an fissures, as small baseline subsets (SBAS) to test the atmospheric effects of differential interferograms pair stepwise, 2-pass differential interferogram with very short baseline perpendicular to generate the whole deformation map with 44 days interval, and finally, corner reflector (CR) technique was used to closely monitor the relative deformation time series between two CRs settled crossing two ground fissures. Results showed that TerraSAR data are a good choice for small-scale ground fissures detection and monitoring, while special considerations should be taken for their great temporal and baseline decorrelation. Secondly, ground fissures in Xi'an were mostly detected at the joint section of stable and deformable regions. Lastly, CR-InSAR had potential ability to monitor relative deformation crossing fissures with millimeter precision.

  2. New composite spectra of Mars, 0.4-5.7 μm

    USGS Publications Warehouse

    Erard, Stephane; Calvin, Wendy M.

    1997-01-01

    About 15 areas were observed in the equatorial regions of Mars by the infrared spectrometers IRS (Mariner 6 and 7) and ISM (Phobos-2). The comparison between the spectra shows a remarkable consistency between two data sets acquired 20 years apart and calibrated independently. This similarity demonstrates the accuracy of ISM calibration above 2 μm, except for a possible stray light contribution above 2.6 μm, on the order of ∼1–2% of the solar flux at 2.7 μm. Most differences in spectral shapes are related to differences in spectral/spatial resolution and viewing geometries. No important variation in surface properties is detected, except for a spot in southern Arabia Terra which has a much deeper hydration feature in IRS spectra; differences in viewing geometries and spatial resolutions do not seem to account for this difference that could result from shifting or dehydration of surface materials. Composite spectra of several types of bright and dark materials are computed by modeling the thermal emission and are completed with telescopic spectra in the visible range. Modeled reflectance in the 3.0–5.7 μm range is consistent with basalts and palagonites. The bright regions and analog palagonite spectra are different from hematite in this range, but resemble several phyllosilicates. We infer that (1) although hematite dominates the spectra in the 0.4- to 2.5-μm range, the silicate-clay host is spectrally active beyond 3 μm and can be identified from this domain; (2) phyllosilicates such as montmorillonite or smectite may be abundant components of the martian soils, although the domain below 3 μm lacks the characteristic features of the most usual terrestrial clay minerals.

  3. Volatile-rich Crater Interior Deposits on Mars: An Energy Balance Model of Modification

    NASA Technical Reports Server (NTRS)

    Russell, Patrick S.; Head, James W.; Hecht, Michael H.

    2003-01-01

    Several craters on Mars are partially filled by material emplaced by post-impact processes. Populations of such craters include those in the circumsouth polar cap region, in Arabia Terra, associated with the Medusae Fossae Formation, and in the northern lowlands proximal to the north polar cap. In this study, crater fill material refers to an interior mound, generally separated from the interior walls of the crater by a trough that may be continuous along the crater s circumference (i.e. a ring-shaped trough), or may only partially contact the crater walls (i.e. a crescent-shaped trough). The fill deposit is frequently off-center from the crater center and may be asymmetric, (i.e. not circular) in plan view shape. Here we test the hypothesis that asymmetries in volatile fill shape, profile, and center-location within a crater result from asymmetries in local energy balance within the crater due mainly to variation of solar insolation and radiative effects of the crater walls over the crater interior. We first focus on Korolev crater in the northern lowlands. We can then apply this model to other craters in different regions. If asymmetry in morphology and location of crater fill are consistent with radiative-dominated asymmetries in energy budget within the crater, then 1) the volatile-rich composition of the fill is supported (this process should not be effective at shaping volcanic or sedimentary deposits), and 2) the dominant factor determining the observed shape of volatile-rich crater fill is the local radiative energy budget within the crater (and erosive processes such as eolian deflation are not necessary).

  4. The Global Distribution of Weathered Glass on Mars

    NASA Astrophysics Data System (ADS)

    Horgan, B.; Chojnacki, M.; Lai, J.; Clarke, D.; Joseph, J.; Bell, J. F.

    2012-12-01

    Weathered iron-bearing glass has been identified as the primary phase in over ten million square kilometers of low-albedo deposits in the northern lowlands of Mars, based on visible to near-infrared (0.36-2.5 μm) spectra from the OMEGA imaging spectrometer onboard Mars Express (Horgan and Bell, 2012). The glass exhibits a concave blue slope in the near-infrared that is consistent with a leached glass rind. This rind is formed during exposure of glass to at least slightly acidic fluids under water-limited conditions, and is commonly observed in dry volcanic environments on Earth. The proposed origin for these materials is explosive volcanism, potentially triggered due to ice-magma interactions in the late Hesperian or Amazonian, followed by post-depositional acidic weathering at the surface. A possible analog for these glass-rich sedimentary terrains are the extensive sand plains, dune fields, and flood plains of Iceland, which are composed of glass-rich (50-90%) volcaniclastic sediments formed during sub-glacial eruptions. The large scale of the martian deposits suggests widespread (and potentially ice-related) explosive volcanism either in the northern lowlands or near the dichotomy boundary. This possibility raises the question: How widespread are glass-rich deposits on Mars globally? To address this question, we have developed a global set of visible/near-infrared OMEGA mosaics at 1 km/pixel resolution. Preliminary analysis of this data set indicates that the concave spectral slope that we associate with weathered glass is present in large portions of the Syrtis Major region, within Mawrth Vallis, and in several dozen dune fields in the regions of Syrtis Major, Arabia Terra, Valles Marineris, and the Argyre Basin. Higher resolution CRISM observations of several Valles Marineris dune fields appear to confirm these preliminary results, as spectra within the dune fields are consistent with iron-bearing glass (Chojnacki et al., 2012). We are currently working to

  5. Partially-Exhumed Crater in Northern Terra Meridiani: Stereo Anaglyph of overlapping coverage in

    NASA Technical Reports Server (NTRS)

    2002-01-01

    MGS MOC Release No. MOC2-316, 8 August 2002 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images have shown time and again that the geology and history of Mars is complex. These two pictures show different views of a circular feature in northern Terra Meridiani at 2.3oN, 356.6oW. The first is a mosaic of 3 MOC narrow angle images acquired in August 1999, November 2000, and June 2002. The black area is a gap in coverage resulting from data lost after transmission from Mars to Earth. The second picture is a stereo ('3-D') anaglyph of a portion of the same circular feature. It has been rotated 90o clockwise to show the stereo effect that results from combining the August 1999 image, which was taken while the spacecraft was pointed nadir (straight down) and the June 2002 image, taken with the spacecraft pointing backwards about 16o (i.e., MGS Relay-16 orientation). The anaglyph should be viewed with '3-D' glasses (red in left eye, blue in the right). The circular feature was once an impact crater. The crater was 2.6 km (1.6 mi) across, about 2.6 times larger than the famous Meteor Crater in northern Arizona. Terra Meridiani, like northern Arizona, is a region of vast exposures of layered sedimentary rock. Like the crater in Arizona, this one was formed by a meteor that impacted a layered rock substrate. Later, this crater was filled and completely buried under more than 100 m (more than 327 ft) of additional layered sediment. The sediment hardened to become rock. Later still, the rock was eroded away--by processes unknown (perhaps wind)--to re-expose the buried crater. The crater today remains mostly filled with sediment, its present rim standing only about 40 m (130 ft) above its surroundings.

  6. Geologic Mapping in Southern Margaritifer Terra

    NASA Technical Reports Server (NTRS)

    Irwin, R. P., III; Grant, J. A.

    2010-01-01

    Margaritifer Terra records a complex geologic history [1-5], and the area from Holden crater through Ladon Valles, Ladon basin, and up to Morava Valles is no exception [e.g., 6-13]. The 1:500,000 geologic map of MTM quadrangles -15027, -20027, -25027, and -25032 (Figs. 1 and 2 [14]) identifies a range of units that delineate the history of water-related activity and regional geologic context.

  7. Is Ishtar Terra a thickened basaltic crust?

    NASA Technical Reports Server (NTRS)

    Arkani-Hamed, Jafar

    1992-01-01

    The mountain belts of Ishtar Terra and the surrounding tesserae are interpreted as compressional regions. The gravity and surface topography of western Ishtar Terra suggest a thick crust of 60-110 km that results from crustal thickening through tectonic processes. Underthrusting was proposed for the regions along Danu Montes and Itzpapalotl Tessera. Crustal thickening was suggested for the entire Ishtar Terra. In this study, three lithospheric models with total thicknesses of 40.75 and 120 km and initial crustal thicknesses of 3.9 and 18 km are examined. These models could be produced by partial melting and chemical differentiation in the upper mantle of a colder, an Earth-like, and a hotter Venus having temperatures of respectively 1300 C, 1400 C, and 1500 C at the base of their thermal boundary layers associated with mantle convection. The effects of basalt-granulite-eclogite transformation (BGET) on the surface topography of a thickening basaltic crust is investigated adopting the experimental phase diagram and density variations through the phase transformation.

  8. Vicarious calibration of Aqua and Terra MODIS

    NASA Astrophysics Data System (ADS)

    Thome, Kurtis J.; Czapla-Myers, Jeffrey S.; Biggar, Stuart F.

    2003-11-01

    The Moderate Resolution Imaging Spectroradiometer (MODIS) is onboard both the Terra and Aqua platforms. An important aspect of the use of MODIS, and other Earth Science Enterprise sensors, has been the characterization and calibration of the sensors and validation of their data products. The Remote Sensing Group at the University of Arizona has been active in this area through the use of ground- based test sites. This paper presents the results from the reflectance-base approach using the Railroad Valley Playa test site in Nevada for both Aqua and Terra MODIS. The key to the approach is the measurement of surface reflectance over a 1-km2 area of the playa and results from this method shows agreement with both MODIS sensors to better than 5%. Early results indicate that while the two sensors both agree with the ground-based measurements to within the uncertainties of the reflectance-based approach, there were significant differences between the Aqua and Terra MODIS for data prior to September 2002. Recent results indicate that this bias, if any, is now within the uncertainties of the reflectance-based method of calibration.

  9. Future of energy demand in Saudi Arabia

    SciTech Connect

    Elshayal, I.M.; Al-Zakri, A.S.

    1981-01-01

    In this study, the most recent papers on this topic were reviewed to examine the future use of nuclear energy in seawater desalination and electric power generation, as well as its impact on the environment in Saudi Arabia. 14 refs.

  10. Geologic Mapping of the Nili Fossae Region of Mars: MTM Quadrangles 20287, 20282, 25287, 25282, 30287, and 30282

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III; Crown, David A.

    2010-01-01

    Geologic mapping studies at the 1:1M-scale are being used to assess geologic materials and processes that shape the highlands along the Arabia Terra dichotomy boundary. In particular, this mapping will provide a regional context and evaluate the distribution, stratigraphic position, and potential lateral continuity of compositionally distinct outcrops identified by spectral instruments currently in orbit (i.e., CRISM and OMEGA). Placing these landscapes, their material units, structural features, and unique compositional outcrops into spatial and temporal context with the remainder of the Arabia Terra dichotomy boundary may provide constraints on: 1) origin of the dichotomy boundary, 2) paleoenvironments and climate conditions, and 3) various fluvial-nival modification processes related to past and present volatile distribution and their putative reservoirs (aquifers, lakes and oceans, surface and ground ice) and the influences of nearby volcanic and tectonic features on hydrologic processes, including hydrothermal alteration, across the region.

  11. NASA's Terra spacecraft is prepared for encapsulation before launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Workers at Vandenberg AFB, Calif., help prepare NASA's Terra spacecraft (right) for encapsulation in the rocket faring (left). Terra is expected to be launched aboard a Lockheed Martin Atlas IIAS rocket Dec. 16 from Space Launch Complex 3 East at Vandenberg. Terra comprises five state-of-the-art sets of instruments that will collect data for continuous, long-term records of the state of Earth's land, oceans and atmosphere. Together with data from other satellite systems launched by NASA and other countries, Terra will inaugurate a new self-consistent data record that will be gathered over the next 15 years. From an altitude of 438 miles, Terra will circle the Earth 16 times a day from pole to pole (98 degree inclination), crossing the equator at 10:30 a.m. The five Terra instruments will operate by measuring sunlight reflected by the Earth and heat emitted by the Earth.

  12. NASA's Terra spacecraft is prepared for encapsulation before launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Terra spacecraft (foreground) is ready for encapsulation in the rocket faring behind it. Terra is expected to be launched aboard a Lockheed Martin Atlas IIAS rocket Dec. 16 from Space Launch Complex 3 East at Vandenberg AFB, Calif. Terra comprises five state-of-the-art sets of instruments that will collect data for continuous, long-term records of the state of Earth's land, oceans and atmosphere. Together with data from other satellite systems launched by NASA and other countries, Terra will inaugurate a new self-consistent data record that will be gathered over the next 15 years. From an altitude of 438 miles, Terra will circle the Earth 16 times a day from pole to pole (98 degree inclination), crossing the equator at 10:30 a.m. The five Terra instruments will operate by measuring sunlight reflected by the Earth and heat emitted by the Earth.

  13. Terra Mission Operations: Launch to the Present (and Beyond)

    NASA Technical Reports Server (NTRS)

    Kelly, Angelita; Moyer, Eric; Mantziaras, Dimitrios; Case, Warren

    2014-01-01

    The Terra satellite, flagship of NASA's long-term Earth Observing System (EOS) Program, continues to provide useful earth science observations well past its 5-year design lifetime. This paper describes the evolution of Terra operations, including challenges and successes and the steps taken to preserve science requirements and prolong spacecraft life. Working cooperatively with the Terra science and instrument teams, including NASA's international partners, the mission operations team has successfully kept the Terra operating continuously, resolving challenges and adjusting operations as needed. Terra retains all of its observing capabilities (except Short Wave Infrared) despite its age. The paper also describes concepts for future operations. This paper will review the Terra spacecraft mission successes and unique spacecraft component designs that provided significant benefits extending mission life and science. In addition, it discusses special activities as well as anomalies and corresponding recovery efforts. Lastly, it discusses future plans for continued operations.

  14. Organ Transplantation in Saudi Arabia.

    PubMed

    Shaheen, Faissal A M

    2016-07-01

    Organ transplantation started in the Kingdom of Saudi Arabia (KSA) in 1979 with a kidney transplanted from a live donor. The Saudi Center for Organ Transplantation has been established in 1985 as a governmental agency that supervises all national transplant activities in the KSA. Organ transplantation in the KSA has made great strides since 1985. Saudi Center for Organ Transplantation is playing a central role in all aspects of transplantation including education on all levels, allocation, coordination and procurement. A new initiative has started an ambitious program in 2014 to improve the identification and reporting of organ donors aiming at an annual rate of 15 donors per million populations within 3 years in the KSA. PMID:27326805

  15. Multihued Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken at JPL shows the panoramic camera used onboard both Mars Exploration Rovers. The panel to the lower right highlights the multicolored filter wheel that allows the camera to see a rainbow of colors, in addition to infrared bands of light. By seeing Mars in all its colors, scientists can gain insight into the different minerals that constitute its rocks and soil.

  16. Geologic Mapping of the Mawrth Vallis Region, Mars: MTM Quadrangles 25022, 25017, 25012, 20022, 20017, and 20012

    NASA Technical Reports Server (NTRS)

    Chuang, F. C.; Bleamaster, L. F., III

    2010-01-01

    Mawrth Vallis is a 15-25 km wide, 500 km long sinuous channel that winds through the highlands of Arabia Terra and debouches into the lowlands of Acidalia Planitia. The Mawrth Vallis region lies along the gradational zone between southern hemisphere thick crust and northern hemisphere thin crust, a topographically distinct portion of the Martian crustal dichotomy. The origin and age of the dichotomy boundary are controversial and are further complicated by the multi-stage and multi-process geologic history that has modified this approximately 6000 km section of the highland-lowland boundary (approximately 5 N, 330E to approximately 30 N, 80 E; herein referred as the Arabia Terra boundary). Furthermore, the Arabia Terra boundary has been subjected to many post-boundary processes such as outflow floods to the west, volcanism and tectonism to the east, and potential volatile deposition and glacial modification to the north. This study seeks to better understand the history of the Mawrth Vallis region by mapping six MTM quadrangles (17.5-27.5 N, 335-350 E) at 1:1M scale using traditional and modern digital geologic mapping techniques.

  17. Topographic Analyses of the Vestalia Terra plateau, Vesta (Invited)

    NASA Astrophysics Data System (ADS)

    Buczkowski, D.; Wyrick, D. Y.; Williams, D. A.; Preusker, F.; Roatsch, T.; DeSanctis, M. C.; Raymond, C. A.; Russell, C. T.

    2013-12-01

    The identification of Vestalia Terra, a topographically high region of Vesta bound by steep scarps, is itself a direct result of topographic analysis of the asteroid. However, additional analysis of the topography of the plateau has yielded important scientific discoveries. While most equatorial regions on Vesta display numerous wide and flat-floored troughs, Vestalia Terra does not. There are, however, three long pit crater chains on top of the plateau that are roughly aligned with the equatorial flat-floor troughs. Pit crater chains are a type of feature that have been observed on several planetary bodies and have been described as lines of circular to elliptical depressions which lack an elevated rim, ejecta deposits, or lava flows. Individual pits most commonly have a conical shape, sometimes with a flat floor, but in some cases they are elliptical in shape, with the long axis parallel to the chain orientation. Pit craters can in many cases coalesce into linear troughs, but the pits are often bordered by a graben (a down-dropped block bounded by normal faults) even before this coalesence. While pits are generally agreed to have formed by collapse into a subsurface cavity, the exact formation mechanisms hypothesized can vary from planet to planet. However, several researchers have suggested that pit crater chains on small bodies such as Phobos, Eros, Lutetia and Enceladus are formed by the drainage of a loose cover material into subsurface voids formed by dilation of a subsurface normal fault, a method described in extensive detail for pit crater chains on Mars. This formation hypothesis is strengthened by the strong correlation between pit crater chains and fault-bounded graben that has been observed and by the fact that pit chains are often in alignment with a regional fault and fracture system. There are two fundamental controls on the maximum size a pit can attain: the thickness of the overlying regolith and the amount of subsurface accommodation space. The

  18. Terra firma-forme dermatosis revisited.

    PubMed

    Browning, John; Rosen, Ted

    2005-01-01

    Terra firma-forme dermatosis is a cutaneous discoloration resembling dirt, hence the clinical name. The dyschromia cannot be removed with routine soap and water washing, but can be eliminated by rubbing with isopropyl alcohol. Although the condition poses no serious medical threat, it is cosmetically distressing. Our experience is that this entity is much more frequent that might be expected when considering the paucity of reports in the readily available medical literature. We chronicle a series of cases to highlight occurrence in widely divergent demographic groups and long duration of remission following appropriate topical intervention. The cause remains unknown. PMID:16150223

  19. Volcanism in Northwest Ishtar Terra, Venus

    SciTech Connect

    Gaddis, L.R.; Greeley, R. )

    1990-10-01

    Evidence is presented for a previously undocumented volcanic complex in the highlands of NW Ishtar Terra (74 deg N, 313 deg E). The proposed valcanic center is in mountainous banded terrain thought to have been formed by regional compression. Data used include Soviet Venera 15/16 radar images and topography (Fotokarta Veneri B-4, 1987). An attempt is made to assess the place of this feature in the framework of known volcanic landforms of the Lakshmi Planum and to examine the relationships between volcanism and tectonism in this region. 38 refs.

  20. Crustal Evolution of the Protonilus Mensae Area, Mars

    NASA Technical Reports Server (NTRS)

    McGill, G. E.; Smrekar, S. E.; Dimitriou, A. M.; Raymond, C. A.

    2004-01-01

    Despite research by numerous geologists and geo- physicists, the age and origin of the martian crustal dichotomy remain uncertain. Models for the origin of this dichotomy involve single or multiple impact, mantle megaplumes, primordial crustal asymmetry, and plate tectonics. Most of these models imply a Noachian age for the dichotomy. A major problem common to all genetic models is the difficulty separating the features resulting from the primary cause for the dichotomy from features due to younger fault- ing, impact cratering, volcanism, deposition, and erosion. highlands (the dichotomy boundary) approximates a small circle that ranges in latitude from about -10 deg. in Elysium Planitia to about +45 deg. north of Arabia Terra. For much of its length the boundary is characterized by relatively steep scarps separating highland plateau to the south from lowland plains to the north, generally with a complex transition zone on the lowland side of these scarps. These scarps are almost certainly due to normal faulting. The type fretted terrain, which defines the boundary in north-central Arabia Terra, also is characterized by scarps but has under- gone a more complex history of faulting and dissection [13]. In some places, notably in the Acidalia Planitia region, the dichotomy boundary is gradational. In the Tharsis region the boundary is obscured by younger volcanics.

  1. Pedogenetic processes on Mars

    NASA Astrophysics Data System (ADS)

    Chiara Tangari, Anna; Marinangeli, Lucia; Piluso, Eugenio; Pompilio, Loredana; Scarciglia, Fabio

    2014-05-01

    Clay minerals, such as Fe/Mg smectite and Al-rich phyllosilicates (i.e., montmorillonite and kaolinite) were detected in the last years on Mars by numerous missions[1,2]. These minerals can be formed by fluid/rock interaction. Therefore, their study may provide important information on the climatic conditions and consequent habitability of the Martian surface. In this work we compare the mineralogy observed with CRISM data in the eastern part of Valles Marineris (Coprates-Ganges-Capri-Eos Chasmata), Margaritifer Terra and Margaritifer Chaos regions, with soils sampled on the Etna volcano (Sicily) and Cerviero Mount (Calabria, Southern Italy). We use an integrated approach of remote sensing coupled with pedological, petrographical and mineralogical investigations. Our purpose, here, is to find possible analogies between some Andosols developed on the basaltic substrates of Etna and Cerviero Mount, and the Martian soils, based on their spectral response and formation processes. CRISM data show poor abundance of clay minerals, such as illite, smectite and montmorillonite, in the eastern part of Valles Marineris. On the contrary, these phases are widely exposed in the Margaritifer Terra and Margaritifer Chaos, where we detected allophone (poorly crystalline clay), vermiculite, chlorite and other phyllosilicates belonging to the smectite group, such as saponite and nontronite. The surrounding area shows dominant signatures of basaltic composition.Our preliminary analysis on terrestrial soil profiles, using X-ray diffraction analysis, shows similar characteristics to Mars in terms of bedrock composition and clay mineralogy. Etnean soils, formed from lavas and pyroclastics of various ages (from 12 ka to 122 BC) [3] show the presence of clay minerals, such as kaolinite and small amounts of illite. The Cerviero Mount soils, developed on pillow basalts of Maastrichtian-Paleocene ages [4] are composed of vermiculite, illite, chlorite and interstratified clays such as

  2. Near and Thermal Infrared Remote Sensing of Bedrock and Sand in Dust-Covered Regions on Mars: Assessing Bedrock Mineralogy Through 'Windows' in the Dust

    NASA Astrophysics Data System (ADS)

    Lai, J. C.; Horgan, B. H.; Bell, J. F.

    2013-12-01

    Bright surface dust masks large regions of Mars from detailed mineralogical and petrological analysis using remote sensing. In order to help address this issue, we assessed a number of orbital data sets to identify and characterize small 'windows' through the dust that may reveal the underlying bedrock. Data sets assessed include the Mars Global Surveyor orbiter (MGS) Thermal Emission Spectrometer (TES) Dust Cover Index (DCI), Mars Odyssey orbiter Thermal Emission Imaging System (THEMIS) thermal imaging, and Mars Reconnaissance Orbiter (MRO) Mars Color Imager (MARCI) color mapping observations. Data from the MGS Mars Orbiter Laser Altimeter (MOLA) and high-resolution visible-wavelength images from the MRO Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE) provided important topographical and morphological context. We have identified and characterized 67 individual windows in four classically bright regions of Mars: Amazonis Planitia, Arabia Terra, Elysium Planitia, and Tharsis Montes. These windows are characterized by having one or more of the following characteristics in contrast with the surrounding terrain: low DCI value, low MARCI and/or TES albedo, and/or high THEMIS night/day temperature contrast. Windows are typically tens of kilometers across but larger ones hundreds of km across have also been found, most notably in Tharsis. The majority of windows are associated with impact craters, most commonly as intracrater splotches or streaks of warm and/or dark material emanating from the crater. Some of these craters contain outcrops and, in some cases, distinct layers of dark material on their walls or central mound, providing opportunities to analyze bedrock. Other types of windows have also been found in smaller numbers, including those located on the flanks and summits of Mars' most prominent volcanoes, in addition to the walls and bases of cliffs tens to hundreds of meters in height. Initial near-IR spectroscopic analysis using our

  3. Mars Underground News.

    NASA Astrophysics Data System (ADS)

    Edgett, K.

    Contents: Next entry to Mars (Mars Pathfinder and the microrover Sojourner). Hello, Mars, we're back! Mars Global Surveyor update. The Mars program - 2001 and beyond. Schedule of missions to Mars (as of June 11, 1997). Mars on the Web.

  4. Synthesis of Spectral Data From the Grey Hematite Regions of Mars

    NASA Astrophysics Data System (ADS)

    Calvin, W.; Fallacaro, A.; Baldridge, A.

    2003-12-01

    The martian surface has been mapped by a number of visible and infrared spectral instruments from orbit. Telescopic and historical data sets noted the global albedo distribution of bright and dark units. Work in the near infrared (1 to 5 μ m) identified subtle spectral variations and the appearance of areas with unique signatures. Broad classification of color and near-infrared spectral units include bright ferric material (dust), dark ferrous material (mafic rocks and pyroxene), dark ``crystalline'' ferric material (low albedo but with strong ferric absorptions) and water of hydration in surface materials. The Thermal Emission Spectrometer (TES) on MGS has identified two dominant surface units (mafic/basaltic and basaltic/andesitic-or-glassy-or-weathered). Small outcrops where the spectral signature of bulk grey hematite is exposed at the surface have been identified in Meridiani, Aram Chaos and Valles Marineris. Data from both the Infrared Spectrometers (IRS) on Mariner 6 and 7 and the Imaging Spectrometer for Mars (ISM) show the hematite locations to be more hydrated than other surface regions. Initial comparisons between ISM and the Gamma Ray Spectrometer (GRS) on Odyssey show the increased infrared signature of water in regions also found by GRS to contain more hydrogen. The GRS also shows a broad enhancement of hydrogen over Meridiani and Arabia which covers the hematite outcrop but is much larger in extent. This can be explained if GRS is sensitive both to surface hydration and water at depth in minerals or ice. The preferred interpretation for the bulk hematite units is an aqueous precipitate and synthesis of multiple spectral data sets support that conclusion. A synthesis of the data from these instruments at the hematite locations will be presented. The largest of the sites, in Terra Meridiani, is the landing site for the ``Opportunity'' Mars Exploration Rover which lands Jan 25, 2004. Consideration of constraints imposed by these orbital data sets

  5. Role of TERRA in the Regulation of Telomere Length

    PubMed Central

    Wang, Caiqin; Zhao, Li; Lu, Shiming

    2015-01-01

    Telomere dysfunction is closely associated with human diseases such as cancer and ageing. Inappropriate changes in telomere length and/or structure result in telomere dysfunction. Telomeres have been considered to be transcriptionally silent, but it was recently demonstrated that mammalian telomeres are transcribed into telomeric repeat-containing RNA (TERRA). TERRA, a long non-coding RNA, participates in the regulation of telomere length, telomerase activity and heterochromatinization. The correct regulation of telomere length may be crucial to telomeric homeostasis and functions. Here, we summarize recent advances in our understanding of the crucial role of TERRA in the maintenance of telomere length, with focus on the variety of mechanisms by which TERRA is involved in the regulation of telomere length. This review aims to enable further understanding of how TERRA-targeted drugs can target telomere-related diseases. PMID:25678850

  6. NASA's Terra spacecraft is prepared for encapsulation before launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Workers (left) at Vandenberg AFB, Calif., get ready to prepare NASA's Terra spacecraft (right) for encapsulation in the rocket faring (left) before launch. The spacecraft is expected to be launched Dec. 16 aboard a Lockheed Martin Atlas IIAS rocket from the AFB's Space Launch Complex 3 East. Terra comprises five state-of-the-art sets of instruments that will collect data for continuous, long-term records of the state of Earth's land, oceans and atmosphere. Together with data from other satellite systems launched by NASA and other countries, Terra will inaugurate a new self-consistent data record that will be gathered over the next 15 years. From an altitude of 438 miles, Terra will circle the Earth 16 times a day from pole to pole (98 degree inclination), crossing the equator at 10:30 a.m. The five Terra instruments will operate by measuring sunlight reflected by the Earth and heat emitted by the Earth.

  7. NASA's Terra spacecraft is prepared for encapsulation before launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Terra spacecraft awaits installation of the instruments that will collect data for continuous, long-term records of the state of Earth's land, oceans and atmosphere. Terra is expected to be launched aboard a Lockheed Martin Atlas IIAS rocket Dec. 16 from Space Launch Complex 3 East at Vandenberg AFB, Calif. Terra comprises five state-of-the-art sets of instruments that, together with data from other satellite systems launched by NASA and other countries, will inaugurate a new self-consistent data record that will be gathered over the next 15 years. From an altitude of 438 miles, Terra will circle the Earth 16 times a day from pole to pole (98 degree inclination), crossing the equator at 10:30 a.m. The five Terra instruments will operate by measuring sunlight reflected by the Earth and heat emitted by the Earth.

  8. Mars Bowling

    NASA Video Gallery

    More than 140 fourth and fifth graders from Kraft Elementary School in Hampton learned how Newton's laws of motion apply to bowling and the Mars Curiosity rover during "The Science of Bowling," an ...

  9. Hydrogeology of Basins on Mars

    NASA Technical Reports Server (NTRS)

    Arvidson, Raymond E.

    2001-01-01

    This document summarizes the work accomplished under NASA Grant NAG5-3870. Emphasis was put on the development of the FIDO rover, a prototype for the twin-Mers which will be operating on the surface of Mars in 2004, specifically the primary work was the analysis of FIDO field trials. The grantees also analyzed VIKING Lander 1 XRFS and Pathfinder APXS data. Results show that the Viking site chemistry is consistent with an andesite, and the Pathfinder site is consistent with a basaltic andesite. The grantees also worked to demonstrate the capability to simulate annealing methods to apply to the inversion of remote sensing data. They performed an initial analyses of Sojourner engineering telemetry and imaging data. They performed initial analyses of Viking Lander Stereo Images, and of Hematite deposits in Terra Meridiani. They also acquired and analyzed the New Goldstone radar data.

  10. Mars Pathfinder

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    First of NASA's Discovery missions. Launched in December 1996 and arrived at Mars on 4 July 1997. Mainly intended as a technology demonstration mission. Used airbags to cushion the landing on Mars. The Carl Sagan Memorial station returned images of an ancient flood plain in Ares Vallis. The 10 kg Sojourner rover used an x-ray spectrometer to study the composition of rocks and travelled about 100 ...

  11. Mars resources

    NASA Technical Reports Server (NTRS)

    Duke, Michael B.

    1986-01-01

    The most important resources of Mars for the early exploration phase will be oxygen and water, derived from the Martian atmosphere and regolith, which will be used for propellant and life support. Rocks and soils may be used in unprocessed form as shielding materials for habitats, or in minimally processed form to expand habitable living and work space. Resources necessary to conduct manufacturing and agricultural projects are potentially available, but will await advanced stages of Mars habitation before they are utilized.

  12. Exploring Mars

    NASA Astrophysics Data System (ADS)

    Breuil, Stéphanie

    2016-04-01

    Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

  13. Mars Exploration Program and Mars Technology Program

    NASA Technical Reports Server (NTRS)

    Whetsel, Charles W.

    2002-01-01

    The Mars Exploration Program and constituent Mars Technology Program are described. Current, ongoing and future NASA-led missions are presented, including discussions of scientific accomplishments and objectives as well as technology validations accomplished and technological enablers for future missions. The missions summarized include (in order of actual or planned launch): Mars Global Surveyor, Mars Pathfinder, 2001 Mars Odyssey, Mars Reconnaissance Orbiter, Mars 'Smart' Lander, Mars Scouts, Mars Sample Return. Key technology areas hdiscussed include: Navigation, Entry, Descent and Landing, Science and Surface Operations, Orbital Transport and Sample Return Technologies.

  14. Validation of CERES/TERRA Data

    NASA Technical Reports Server (NTRS)

    Barkstrom, Bruce R.; Wieliski, Bruce A.; Smith, G. Louis; Lee, Robert B.; Priestley, Kory J.; Charlock, Thomas P.; Kratz, David P.

    2000-01-01

    There are 2 CERES scanning radiometer instruments aboard the TERRA spacecraft, one for mapping the solar radiation reflected from the Earth and the outgoing longwave radiation and the other for measuring the anisotropy of the radiation. Each CERES instrument has on-board calibration devices, which have demonstrated that from ground to orbit the broadband total and shortwave sensor responses maintained their ties to the International Temperature Scale of 1990 at precisions approaching radiances have been validated in orbit to +/- 0.3 % (0.3 W/sq m sr). Top of atmosphere fluxes are produced by use of the CERES data alone. By including data from other instruments, surface radiation fluxes and radiant fluxes within the atmosphere and at its top, shortwave and longwave, for both up and down components, are derived. Validation of these data products requires ground and aircraft measurements of fluxes and of cloud properties.

  15. Bilateral topographic symmetry patterns across Aphrodite Terra, Venus

    NASA Technical Reports Server (NTRS)

    Crumpler, L. S.; Head, James W.

    1988-01-01

    Topographic profiles have been obtained across Aphrodite Terra to test for bilateral symmetry of the type associated with thermal boundary layer topography at divergent plate boundaries on earth. In addition to a broad bilateral symmetry at a range of angles across Aphrodite Terra, detailed bilateral symmetry is noted within domains between linear discontinuities in directions parallel to the strike of the discontinuities. The results suggest that western Aphrodite Terra is similar to terrestrial oceanic divergent plate boundary environments, and that the cross-strike discontinuities are analogous to oceanic fracture zones rather than strike-slip faults.

  16. The Education of Women in Saudi Arabia.

    ERIC Educational Resources Information Center

    Al Rawaf, Haya Saad; Simmons, Cyril

    1991-01-01

    Describes the development and expansion of formal education for women in Saudi Arabia since 1960. Discusses girls' curriculum in elementary and secondary schools, the influence of conservative attitudes toward sex roles, and the growth of female higher education despite a lack of female employment. Contains 20 references. (SV)

  17. English Language Teaching Profile: Saudi Arabia.

    ERIC Educational Resources Information Center

    British Council, London (England). English Language and Literature Div.

    The role and status of English in Saudi Arabia are examined, with attention directed to: (1) English within the education system; (2) teachers of English; (3) English outside the education system; (4) materials support; (5) British support for the teaching of English; and (6) English syllabi at intermediate, secondary, and higher education levels.…

  18. Making a Smart Campus in Saudi Arabia

    ERIC Educational Resources Information Center

    Abuelyaman, Eltayab Salih

    2008-01-01

    Prince Sultan University (PSU) in Riyadh, Saudi Arabia, has conceptualized what it means to be a smart campus after surveying similar notions worldwide. A "smart" campus requires smart teachers, smart technology, and smart pedagogical centers. It deploys smart teachers and gives them smart tools and ongoing support to do their jobs while…

  19. Cenozoic volcanic rocks of Saudi Arabia

    USGS Publications Warehouse

    Coleman, R.G.; Gregory, R.T.; Brown, G.F.

    2016-01-01

    The historical record of volcanic activity in Saudi Arabia suggests that volcanism is dormant. The harrats should be evaluated for their potential as volcanic hazards and as sources of geothermal energy. The volcanic rocks are natural traps for groundwater; thus water resources for agriculture may be significant and should be investigated.

  20. Online Continuing Medical Education in Saudi Arabia

    ERIC Educational Resources Information Center

    Alwadie, Adnan D.

    2013-01-01

    As the largest country in the Middle East, Saudi Arabia and its health care system are well positioned to embark on an online learning intervention so that health care providers in all areas of the country have the resources for updating their professional knowledge and skills. After a brief introduction, online continuing medical education is…

  1. Physical therapy education in Saudi Arabia

    PubMed Central

    Alghadir, Ahmad; Zafar, Hamayun; Iqbal, Zaheen Ahmed; Anwer, Shahnawaz

    2015-01-01

    [Purpose] To review the physical therapy educational program model, professional curriculum, and gender representation at major universities, as well as the quality and scope of physical therapy practice in Saudi Arabia. [Methods] Information regarding course curriculum, gender representation, and the quality and scope of physical therapy practice was collected from six universities in Saudi Arabia, the Saudi Physical Therapy Association, and the Saudi Health Commission. [Results] The first bachelor’s degree course of physical therapy was started in Saudi Arabia more than 30 years ago. In the last 10 years, the number of universities offering a bachelor’s degree in physical therapy has risen from 6 to 16, of which 14 are governmental and two are private. The 5- to 6 year bachelor’s degree program in physiotherapy includes an internship and preparatory prerequisite courses. Postgraduate study in physical therapy was introduced in 2000. Most universities offer segregated physical therapy courses for male and female students. [Conclusion] The enrollment of students in physical therapy programs in Saudi Arabia is gradually increasing. There are many opportunities to extend the scope of practice and contribute to the health needs of the Arab population and international communities. PMID:26157276

  2. 4. DETAIL OF TERRA COTTA DECORATION AT TOP OF EXPRESSED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. DETAIL OF TERRA COTTA DECORATION AT TOP OF EXPRESSED COLUMN, JUST ABOVE FOURTH FLOOR WINDOWS ON SOUTH FRONT FACADE - John D. Van Allen & Son Store, South Fifth Avenue & Second Street, Clinton, Clinton County, IA

  3. 3. DETAIL OF TERRA COTTA DECORATION ON LOWER END OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. DETAIL OF TERRA COTTA DECORATION ON LOWER END OF EXPRESSED COLUMN, JUST BELOW SECOND FLOOR ON SOUTH FRONT FACADE - John D. Van Allen & Son Store, South Fifth Avenue & Second Street, Clinton, Clinton County, IA

  4. Detail, terra cotta, ironwork, and painted wood "worm gear" carved ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail, terra cotta, ironwork, and painted wood "worm gear" carved columns, north rear. - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  5. SSF Terra-FM1 Ed3A

    Atmospheric Science Data Center

    2016-07-13

    SSF Terra-FM1 Ed3A Project Title:  CERES Discipline:  Clouds Radiation Budget ...   Reverb Tutorial Subset/Visualization Tool: CERES Order Tool Subset Data:  CERES Search and Subset Tool (HDF4 & ...

  6. TERRA promotes telomerase-mediated telomere elongation in Schizosaccharomyces pombe.

    PubMed

    Moravec, Martin; Wischnewski, Harry; Bah, Amadou; Hu, Yan; Liu, Na; Lafranchi, Lorenzo; King, Megan C; Azzalin, Claus M

    2016-07-01

    Telomerase-mediated telomere elongation provides cell populations with the ability to proliferate indefinitely. Telomerase is capable of recognizing and extending the shortest telomeres in cells; nevertheless, how this mechanism is executed remains unclear. Here, we show that, in the fission yeast Schizosaccharomyces pombe, shortened telomeres are highly transcribed into the evolutionarily conserved long noncoding RNA TERRA A fraction of TERRA produced upon telomere shortening is polyadenylated and largely devoid of telomeric repeats, and furthermore, telomerase physically interacts with this polyadenylated TERRA in vivo We also show that experimentally enhanced transcription of a manipulated telomere promotes its association with telomerase and concomitant elongation. Our data represent the first direct evidence that TERRA stimulates telomerase recruitment and activity at chromosome ends in an organism with human-like telomeres. PMID:27154402

  7. NASA's Terra spacecraft is prepared for encapsulation before launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The rocket faring is lifted up the launch tower for mating with the Lockheed Martin Atlas IIAS rocket after encapsulation of Terra, formerly EOS AM-1. It is scheduled for launch Dec. 16 from Space Launch Complex 3 East at Vandenberg AFB, Calif. Terra comprises five state-of-the-art sets of instruments that will collect data for continuous, long-term records of the state of Earth's land, oceans and atmosphere. Together with data from other satellite systems launched by NASA and other countries, it will inaugurate a new self-consistent data record that will be gathered over the next 15 years. From an altitude of 438 miles, Terra will circle the Earth 16 times a day from pole to pole (98 degree inclination), crossing the equator at 10:30 a.m. The five Terra instruments will operate by measuring sunlight reflected by the Earth and heat emitted by the Earth.

  8. Completion and Submission of the Terra Sirenum Map Project

    NASA Astrophysics Data System (ADS)

    Anderson, R. C.; Dohm, J. M.; Robbins, S.; Schroeder, J.

    2016-06-01

    We have completed and plan to submit a detailed 1:5,000,000-scale geologic map of the Terra Sirenum region, which includes mapping stratigraphic units and identifying tectonic, erosional, depositional, and impact structures.

  9. Mars 2003

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-402, 25 June 2003

    The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) experiment consists of 3 different cameras: a narrow angle imager that provides the black-and-white high resolution views (up to 1.4 meters per pixel) of Mars, and 2 wide angle cameras, observing in red and blue wavelengths, from which color views of the entire planet are assembled each day. The wide angle cameras provide a daily record of changes in martian weather and surface frost as the seasons progress. MGS MOC has obtained a record of martian weather spanning a little over 2 martian years since it began systematic observations in March 1999.

    The view of Mars shown here was assembled from MOC daily global images obtained on May 12, 2003. At that time, the northern hemisphere was in early autumn, and the southern hemisphere in early spring. At the left/center of this view are the four large Tharsis volcanoes: Olympus Mons, Ascraeus Mons, Pavonis Mons, and Arsia Mons. Stretching across the center of the globe is the 5,000 kilometers (3,000 miles) long Valles Marineris trough system. The seasonal south polar carbon dioxide frost cap is visible at the bottom of this view. A dust storm sweeps across the plains of northern Acidalia at the upper right. North is up, east is right, sunlight illuminates the planet from the left.

  10. Case study of climatic changes in Martian fluvial systems at Xanthe Terra

    NASA Astrophysics Data System (ADS)

    Kereszturi, Akos

    2014-06-01

    An unnamed valley system was analyzed in Xanthe Terra south of Havel Vallis on Mars where three separate episodes of fluvial activity could be identified with different morphology, water source and erosional processes, inferring formation under different climatic conditions. The oldest scattered valleys (1. group) form interconnecting network and suggest areally distributed water source. Later two valley types formed from confined water source partly supported by possible subsurface water. The smaller upper reaches (2. group) with three separate segments and also a similar aged but areal washed terrain suggest contribution from shallow subsurface inflow. These valleys fed the main channel (3. group), which morphology (wide, theater shaped source, few tributaries, steep walls) is the most compatible with the subsurface sapping origin. While the first valley group formed in the Noachian, the other two, more confined groups are younger. Their crater density based age value is uncertain, and could be only 1200 million years. After these three fluvial episodes etch pitted, heavily eroded terrain formed possibly by ice sublimation driven collapse. More recently (60-200 million years ago) dunes covered the bottom of the valleys, and finally the youngest event took place when mass movements produced debris covered the valleys' slopes with sediments along their wall around 5-15 million years ago, suggesting wind activity finished earlier than the mass movements in the region. This small area represents the sequence of events probably appeared on global scale: the general cooling and drying environment of Mars. Comparing the longitudinal profiles here to other valleys in Xanthe Terra, convex shaped valley profiles are usually connected to steep terrains. The location of erosional base might play an important role in their formation that can be produced convex shapes where the erosional base descended topographically (by deep impact crater or deep outflow channel formation

  11. NASA's Terra spacecraft is prepared for encapsulation before launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Terra spacecraft (right) is prepared for encapsulation in the rocket faring (left) before launch at Vandenberg AFB, Calif. The faring displays a logo of the many science instruments that make up Terra. The spacecraft's launch aboard a Lockheed Martin Atlas IIAS rocket is scheduled for Dec. 16 from Space Launch Complex 3 East at Vandenberg. Terra comprises five state-of-the- art sets of instruments that will collect data for continuous, long-term records of the state of Earth's land, oceans and atmosphere. Together with data from other satellite systems launched by NASA and other countries, Terra will inaugurate a new self-consistent data record that will be gathered over the next 15 years. From an altitude of 438 miles, Terra will circle the Earth 16 times a day from pole to pole (98 degree inclination), crossing the equator at 10:30 a.m. The five Terra instruments will operate by measuring sunlight reflected by the Earth and heat emitted by the Earth.

  12. Terra - 15 Years as the Earth Observing System Flagship Observatory

    NASA Astrophysics Data System (ADS)

    Thome, K. J.

    2014-12-01

    Terra marks its 15th year on orbit with an array of accomplishments and the potential to do much more. Efforts continue to extend the Terra data record to make its data more valuable by creating a record length to examine interannual variability, observe trends on the decadal scale, and gather statistics relevant to climate metrics. Continued data from Terra's complementary instruments will play a key role in creating the data record needed for scientists to develop an understanding of our climate system. Terra's suite of instruments: ASTER (contributed by the Japanese Ministry of Economy and Trade and Industry with a JPL-led US Science Team), CERES (NASA LaRC - PI), MISR (JPL - PI), MODIS (NASA GSFC), and MOPITT (sponsored by Canadian Space Agency with NCAR-led Science Team) are providing an unprecedented 81 core data products. The annual demand for Terra data remains with >120 million files distributed in 2011 and >157 million in 2012. More than 1,100 peer-reviewed publications appeared in 2012 using Terra data bringing the lifetime total >7,600. Citation numbers of 21,000 for 2012 and over 100,000 for the mission's lifetime. The power of Terra is in the high quality of the data calibration, sensor characterization, and the complementary nature of the instruments covering a range of scientific measurements as well as scales. The broad range of products enable the community to provide answers to the overarching question, "How is the Earth changing and what are the consequences for life on Earth?" Terra continues to provide data that: (1) Extend the baseline of morning-orbit collections; (2) Enable comparison of measurements acquired from past high-impact events; (3) Add value to recently-launched and soon-to-be launched missions, and upcoming field programs. Terra data continue to support monitoring and relief efforts for natural and man-made disasters that involve U.S. interests. Terra also contributes to Applications Focus Areas supporting the U.S. National

  13. Sulfates on Mars: Indicators of Aqueous Processes

    NASA Technical Reports Server (NTRS)

    Bishop, Janice L.; Lane, Melissa D.; Dyar, M. Darby; Brown, Adrian J.

    2006-01-01

    Recent analyses by MER instruments at Meridiani Planum and Gusev crater and the OMEGA instrument on Mars Express have provided detailed information about the presence of sulfates on Mars [1,2,3]. We are evaluating these recent data in an integrated multi-disciplinary study of visible-near-infrared, mid-IR and Mossbauer spectra of several sulfate minerals and sulfate-rich analog sites. Our analyses suggest that hydrated iron sulfates may account for features observed in Mossbauer and mid-IR spectra of Martian soils [4]. The sulfate minerals kieserite, gypsum and other hydrated sulfates have been identified in OMEGA spectra in the layered terrains in Valles Marineris and Terra Meridiani [2]. These recent discoveries emphasize the importance of studying sulfate minerals as tracers of aqueous processes. The sulfate-rich rock outcrops observed in Meridiani Planum may have formed in an acidic environment similar to acid rock drainage environments on Earth [5]. Because microorganisms typically are involved in the oxidation of sulfides to sulfates in terrestrial sites, sulfate-rich rock outcrops on Mars may be a good location to search for evidence of past life on that planet. Whether or not life evolved on Mars, following the trail of sulfate minerals will lead to a better understanding of aqueous processes and chemical weathering.

  14. Waters and desalination programs of Saudi Arabia

    SciTech Connect

    Wojcik, C.K.; Maadhah, A.G.

    1981-07-01

    Saudi Arabia is an arid desert country without rivers or sweet-water lakes. It does, however, have large amounts of ground water and seawater. These waters must be desalted by some means in order to make them potable. The most frequently used methods for that purpose are: multistage flash (MSF) evaporation, reverse osmosis (RO), and electrodialysis (ED). Because of rapid industrialization of the country, the demand for fresh water has been growing steadily. This, in turn, has resulted in a spectacular growth of the water-desalination industry. This paper discusses the availability and properties of the waters. It gives a detailed description of the major accomplishments and of the ongoing and future programs in the field of water desalination in Saudi Arabia. 14 references, 6 figures, 8 tables.

  15. Mars habitat

    NASA Technical Reports Server (NTRS)

    Ayers, Dale; Barnes, Timothy; Bryant, Woody; Chowdhury, Parveen; Dillard, Joe; Gardner, Vernadette; Gregory, George; Harmon, Cheryl; Harrell, Brock; Hilton, Sherrill

    1991-01-01

    The objective of this study is to develop a conceptual design for a permanently manned, self-sustaining Martian facility, to accommodate a crew of 20 people. The goal is to incorporate the major functions required for long term habitation in the isolation of a barren planet into a thriving ecosystem. These functions include living, working, service, and medical facilities as well as a green house. The main design task was to focus on the internal layout while investigating the appropriate structure, materials, and construction techniques. The general concept was to create a comfortable, safe living environment for the crew members for a stay of six to twelve months on Mars. Two different concepts were investigated, a modular assembly reusable structure (MARS) designated Lavapolis, and a prefabricated space frame structure called Hexamars. Both models take into account factors such as future expansion, radiation shielding, and ease of assembly.

  16. Aedes mosquito species in western Saudi Arabia.

    PubMed

    Alikhan, Masroor; Al Ghamdi, Khalid; Mahyoub, Jazem Abdullah

    2014-01-01

    The Aedes Meigen (Diptera: Culicidae) mosquito species populations in the western region of Saudi Arabia, especially in and around Jeddah, are increasing, therefore increasing susceptibility of humans to the dengue virus. An extensive survey was carried out for one year, and four species were identified with the help of different pictorial keys available. The identification was based on morphological characteristics of adult female Aedes mosquitoes. PMID:25373216

  17. Dust Storm, Red Sea and Saudi Arabia

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Outlined against the dark blue water of the Red Sea, a prominent dust storm is making its way across the Red Sea into Saudi Arabia (22.0N, 39.0E) between the Islamic holy cities of Medinah and Mecca. Funneled through a gap in the coastal ranges of southern Sudan near the Ethiopian border, dust storms frequently will blow counter to the prevailing tropical easterly winds of the region.

  18. Telomeric repeat-containing RNA (TERRA) constitutes a nucleoprotein component of extracellular inflammatory exosomes

    PubMed Central

    Wang, Zhuo; Deng, Zhong; Dahmane, Nadia; Tsai, Kevin; Wang, Pu; Williams, Dewight R.; Kossenkov, Andrew V.; Showe, Louise C.; Zhang, Rugang; Huang, Qihong; Conejo-Garcia, José R.; Lieberman, Paul M.

    2015-01-01

    Telomeric repeat-containing RNA (TERRA) has been identified as a telomere-associated regulator of chromosome end protection. Here, we report that TERRA can also be found in extracellular fractions that stimulate innate immune signaling. We identified extracellular forms of TERRA in mouse tumor and embryonic brain tissue, as well as in human tissue culture cell lines using RNA in situ hybridization. RNA-seq analyses revealed TERRA to be among the most highly represented transcripts in extracellular fractions derived from both normal and cancer patient blood plasma. Cell-free TERRA (cfTERRA) could be isolated from the exosome fractions derived from human lymphoblastoid cell line (LCL) culture media. cfTERRA is a shorter form (∼200 nt) of cellular TERRA and copurifies with CD63- and CD83-positive exosome vesicles that could be visualized by cyro-electron microscopy. These fractions were also enriched for histone proteins that physically associate with TERRA in extracellular ChIP assays. Incubation of cfTERRA-containing exosomes with peripheral blood mononuclear cells stimulated transcription of several inflammatory cytokine genes, including TNFα, IL6, and C-X-C chemokine 10 (CXCL10) Exosomes engineered with elevated TERRA or liposomes with synthetic TERRA further stimulated inflammatory cytokines, suggesting that exosome-associated TERRA augments innate immune signaling. These findings imply a previously unidentified extrinsic function for TERRA and a mechanism of communication between telomeres and innate immune signals in tissue and tumor microenvironments. PMID:26578789

  19. Search for Chemically Bound Water in the Surface Layer of Mars Based on HEND/Mars Odyssey Data

    NASA Technical Reports Server (NTRS)

    Basilevsky, A. T.; Litvak, M. L.; Mitrofanov, I. G.; Boynton, W.; Saunders, R. S.

    2003-01-01

    This study is emphasized on search for signatures of chemically bound water in surface layer of Mars based on data acquired by High Energy Neutron Detector (HEND) which is part of the Mars Odyssey Gamma Ray Spectrometer (GRS). Fluxes of epithermal (probe the upper 1-2 m) and fast (the upper 20-30 cm) neutrons, considered in this work, were measured since mid February till mid June 2002. First analysis of this data set with emphasis of chemically bound water was made. Early publications of the GRS results reported low neutron flux at high latitudes, interpreted as signature of ground water ice, and in two low latitude areas: Arabia and SW of Olympus Mons (SWOM), interpreted as 'geographic variations in the amount of chemically and/or physically bound H2O and or OH...'. It is clear that surface materials of Mars do contain chemically bound water, but its amounts are poorly known and its geographic distribution was not analyzed.

  20. BOOK REVIEW: European Perceptions of Terra Australis

    NASA Astrophysics Data System (ADS)

    Sterken, Christiaan

    2012-12-01

    Terra Australis - the southern land - has been one of the most widespread concepts in European geography from the sixteenth to the eighteenth century. This book comprises a set of 14 interdisciplinary scholarly contributions that deal with personal perceptions of Terra Australis by cartographers and explorers, and with putting these perceptions in their historical and cultural environments. This book seems, at a first glance, to be very remote from astronomy - and even from the history of astronomy - however, as it also offers an excellent background to Captain James Cook's second voyage to observe the 1769 transit of Venus from Tahiti, it definitely is a work of truly interdisciplinary character. Cook's voyages, in fact, became a model in which key scientists of many nationalities and disciplines traveled together on ships. In these voyages, art, science, technology and political power were centralised and united. The chapters range across history, the visual arts, literature, popular culture, technology, politics and science. Issues of scientific reasoning are raised in the description of how people did think about the south before there even existed a perception of the unknown land - quite comparable to how ancient and early-modern astronomers had their thought about cosmology even before any observational data were available. Several early map systems - like the zonal and T-O maps (medieval world maps with the letter T inside an O representing the lands inside a circle of oceans) - are described, and the description of Roman geography shows the amazing fact that theory and practice were not unified, and existed independently of each other insofar that a real paradox between theory and observation had persisted for a very long time. The maps and charts also exemplify the long-lasting consequences of early modern copy-paste practice: navigators copied original sketch charts of coasts that were previously unknown to them, herewith committing many translation and

  1. Synergism of MODIS Aerosol Remote Sensing from Terra and Aqua

    NASA Technical Reports Server (NTRS)

    Ichoku, Charles; Kaufman, Yoram J.; Remer, Lorraine A.

    2003-01-01

    The MODerate-resolution Imaging Spectro-radiometer (MODIS) sensors, aboard the Earth Observing System (EOS) Terra and Aqua satellites, are showing excellent competence at measuring the global distribution and properties of aerosols. Terra and Aqua were launched on December 18, 1999 and May 4, 2002 respectively, with daytime equator crossing times of approximately 10:30 am and 1:30 pm respectively. Several aerosol parameters are retrieved at 10-km spatial resolution from MODIS daytime data over land and ocean surfaces. The parameters retrieved include: aerosol optical thickness (AOT) at 0.47, 0.55 and 0.66 micron wavelengths over land, and at 0.47, 0.55, 0.66, 0.87, 1.2, 1.6, and 2.1 microns over ocean; Angstrom exponent over land and ocean; and effective radii, and the proportion of AOT contributed by the small mode aerosols over ocean. Since the beginning of its operation, the quality of Terra-MODIS aerosol products (especially AOT) have been evaluated periodically by cross-correlation with equivalent data sets acquired by ground-based (and occasionally also airborne) sunphotometers, particularly those coordinated within the framework of the AErosol Robotic NETwork (AERONET). Terra-MODIS AOT data have been found to meet or exceed pre-launch accuracy expectations, and have been applied to various studies dealing with local, regional, and global aerosol monitoring. The results of these Terra-MODIS aerosol data validation efforts and studies have been reported in several scientific papers and conferences. Although Aqua-MODIS is still young, it is already yielding formidable aerosol data products, which are also subjected to careful periodic evaluation similar to that implemented for the Terra-MODIS products. This paper presents results of validation of Aqua-MODIS aerosol products with AERONET, as well as comparative evaluation against corresponding Terra-MODIS data. In addition, we show interesting independent and synergistic applications of MODIS aerosol data from

  2. Effect of MODIS Terra radiometric calibration improvements on Collection 6 Deep Blue aerosol products: Validation and Terra/Aqua consistency

    NASA Astrophysics Data System (ADS)

    Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.; Jeong, M.-J.; Meister, G.

    2015-12-01

    The Deep Blue (DB) algorithm's primary data product is midvisible aerosol optical depth (AOD). DB applied to Moderate Resolution Imaging Spectroradiometer (MODIS) measurements provides a data record since early 2000 for MODIS Terra and mid-2002 for MODIS Aqua. In the previous data version (Collection 5, C5), DB production from Terra was halted in 2007 due to sensor degradation; the new Collection 6 (C6) has both improved science algorithms and sensor radiometric calibration. This includes additional calibration corrections developed by the Ocean Biology Processing Group to address MODIS Terra's gain, polarization sensitivity, and detector response versus scan angle, meaning DB can now be applied to the whole Terra record. Through validation with Aerosol Robotic Network (AERONET) data, it is shown that the C6 DB Terra AOD quality is stable throughout the mission to date. Compared to the C5 calibration, in recent years the RMS error compared to AERONET is smaller by ˜0.04 over bright (e.g., desert) and ˜0.01-0.02 over darker (e.g., vegetated) land surfaces, and the fraction of points in agreement with AERONET within expected retrieval uncertainty higher by ˜10% and ˜5%, respectively. Comparisons to the Aqua C6 time series reveal a high level of correspondence between the two MODIS DB data records, with a small positive (Terra-Aqua) average AOD offset <0.01. The analysis demonstrates both the efficacy of the new radiometric calibration efforts and that the C6 MODIS Terra DB AOD data remain stable (to better than 0.01 AOD) throughout the mission to date, suitable for quantitative scientific analyses.

  3. Effect of MODIS Terra Radiometric Calibration Improvements on Collection 6 Deep Blue Aerosol Products: Validation and Terra/Aqua Consistency

    NASA Technical Reports Server (NTRS)

    Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.; Jeong, M.-J.; Meister, G.

    2015-01-01

    The Deep Blue (DB) algorithm's primary data product is midvisible aerosol optical depth (AOD). DB applied to Moderate Resolution Imaging Spectroradiometer (MODIS) measurements provides a data record since early 2000 for MODIS Terra and mid-2002 for MODIS Aqua. In the previous data version (Collection 5, C5), DB production from Terra was halted in 2007 due to sensor degradation; the new Collection 6 (C6) has both improved science algorithms and sensor radiometric calibration. This includes additional calibration corrections developed by the Ocean Biology Processing Group to address MODIS Terra's gain, polarization sensitivity, and detector response versus scan angle, meaning DB can now be applied to the whole Terra record. Through validation with Aerosol Robotic Network (AERONET) data, it is shown that the C6 DB Terra AOD quality is stable throughout the mission to date. Compared to the C5 calibration, in recent years the RMS error compared to AERONET is smaller by approximately 0.04 over bright (e.g., desert) and approximately 0.01-0.02 over darker (e.g., vegetated) land surfaces, and the fraction of points in agreement with AERONET within expected retrieval uncertainty higher by approximately 10% and approximately 5%, respectively. Comparisons to the Aqua C6 time series reveal a high level of correspondence between the two MODIS DB data records, with a small positive (Terra-Aqua) average AOD offset <0.01. The analysis demonstrates both the efficacy of the new radiometric calibration efforts and that the C6 MODIS Terra DB AOD data remain stable (to better than 0.01 AOD) throughout the mission to date, suitable for quantitative scientific analyses.

  4. Identification of New Genomospecies in the Mycobacterium terrae Complex

    PubMed Central

    Ngeow, Yun Fong; Wong, Yan Ling; Tan, Joon Liang; Hong, Kar Wai; Ng, Hien Fuh; Ong, Bee Lee; Chan, Kok Gan

    2015-01-01

    Members of the Mycobacterium terrae complex are slow-growing, non-chromogenic acid-fast bacilli found in the natural environment and occasionally in clinical material. These genetically closely-related members are difficult to differentiate by conventional phenotypic and molecular tests. In this paper we describe the use of whole genome data for the identification of four strains genetically similar to Mycobacterium sp. JDM601, a newly identified member of the M. terrae complex. Phylogenetic information from the alignment of genome-wide orthologous genes and single nucleotide polymorphisms show consistent clustering of the four strains together with M. sp. JDM601 into a distinct clade separate from other rapid and slow growing mycobacterial species. More detailed inter-strain comparisons using average nucleotide identity, tetra-nucleotide frequencies and analysis of synteny indicate that our strains are closely related to but not of the same species as M. sp. JDM601. Besides the 16S rRNA signature described previously for the M. terrae complex, five more hypothetical proteins were found that are potentially useful for the rapid identification of mycobacterial species belonging to the M. terrae complex. This paper illustrates the versatile utilization of whole genome data for the delineation of new bacterial species and introduces four new genomospecies to add to current members in the M. terrae complex. PMID:25830768

  5. NASA's Terra spacecraft is prepared for encapsulation before launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The rocket faring (left) displays a logo of the many science instruments that make up NASA's Terra spacecraft (background). When fully assembled, Terra will be encapsulated in the faring before launch, scheduled for Dec. 16 aboard a Lockheed Martin Atlas IIAS rocket from Space Launch Complex 3 East at Vandenberg AFB, Calif. Terra comprises five state-of-the-art sets of instruments that will collect data for continuous, long-term records of the state of Earth's land, oceans and atmosphere. Together with data from other satellite systems launched by NASA and other countries, it will inaugurate a new self-consistent data record that will be gathered over the next 15 years. From an altitude of 438 miles, Terra will circle the Earth 16 times a day from pole to pole (98 degree inclination), crossing the equator at 10:30 a.m. The five Terra instruments will operate by measuring sunlight reflected by the Earth and heat emitted by the Earth.

  6. NASA Mars Conference

    SciTech Connect

    Reiber, D.B.

    1988-01-01

    Papers about Mars and Mars exploration are presented, covering topics such as Martian history, geology, volcanism, channels, moons, atmosphere, meteorology, water on the planet, and the possibility of life. The unmanned exploration of Mars is discussed, including the Phobos Mission, the Mars Observer, the Mars Aeronomy Observer, the seismic network, Mars sample return missions, and the Mars Ball, an inflatable-sectored-tire rover concept. Issues dealing with manned exploration of Mars are examined, such as the reasons for exploring Mars, mission scenarios, a transportation system for routine visits, technologies for Mars expeditions, the human factors for Mars missions, life support systems, living and working on Mars, and the report of the National Commission on Space.

  7. Demographic perspectives on Saudi Arabia's development.

    PubMed

    Looney, R E

    1985-06-01

    Demographic movements likely to be taking place in Saudi Arabia were hypothesized on the basis of general knowledge. The discussion reports on population size, general Arab demographic patterns, general determinants of fertility, Arab fertility patterns, Saudi fertility patterns, mortality in general, mortality in the Middle East, mortality in Saudi Arabia, Saudi Arabian population growth, immigration, the changing composition of the work force, and third plan targets. Some doubt exists as to the size of Saudi Arabia's population, but there is little question that the total is growing rapidly. This expansion is taking place through stepped up immigration and a relatively high natural growth of indigenous Saudis, but statistics on population size, structure, and on the number of births and deaths leaves the magnitude of a number of important demographic trends in doubt. Yet, considerable evidence exists that several of the Arab countries in the region with fairly good demographic data are likely to have similar demographic patterns. In depth analysis of the demographic dynamics of these countries, particularly Jordan and Kuwait, identified several common elements bearing on several key parameters. Using what Saudi data is available and making comparisons with these neighboring countries, one can, based on expected levels of birth and death rates, indirectly infer the natural growth of Saudi Arabia's population. With several notable exceptions, Saudi Arabia's demographic patterns show a marked similarity to those experienced in the region as a whole. The average rate of population growth in both Saudi Arabia and the Arab region is about 3% a year and in both instances fertility rates are high. The demographic structure of these countries is characterized by the youthfulness of the population. In most of the Arab countries, the population aged 15 years or under accounts for over 48% of the population. The rate of the economically active population is low, ranging from

  8. Women and Education in Saudi Arabia: Challenges and Achievements

    ERIC Educational Resources Information Center

    Hamdan, Amani

    2005-01-01

    The historical socio-economic and political conditions of Saudi Arabia are an essential aspect of understanding a woman's position in Saudi society. The persistence of women's exclusion from public life in contemporary Saudi Arabia is one of the most heated debates not only among Muslims but also worldwide, as Saudi society comes under more and…

  9. Special Education in Saudi Arabia: Challenges, Perspectives, Future Possibilities

    ERIC Educational Resources Information Center

    Alquraini, Turki

    2011-01-01

    This paper provides a brief background of the education system in Saudi Arabia and current special education services and programs for students with disabilities. Additionally, this paper presents the findings of some studies that examined teachers' perspectives regarding the inclusion of students with disabilities. As Saudi Arabia continues its…

  10. Mars @ ASDC

    NASA Astrophysics Data System (ADS)

    Carraro, Francesco

    "Mars @ ASDC" is a project born with the goal of using the new web technologies to assist researches involved in the study of Mars. This project employs Mars map and javascript APIs provided by Google to visualize data acquired by space missions on the planet. So far, visualization of tracks acquired by MARSIS and regions observed by VIRTIS-Rosetta has been implemented. The main reason for the creation of this kind of tool is the difficulty in handling hundreds or thousands of acquisitions, like the ones from MARSIS, and the consequent difficulty in finding observations related to a particular region. This led to the development of a tool which allows to search for acquisitions either by defining the region of interest through a set of geometrical parameters or by manually selecting the region on the map through a few mouse clicks The system allows the visualization of tracks (acquired by MARSIS) or regions (acquired by VIRTIS-Rosetta) which intersect the user defined region. MARSIS tracks can be visualized both in Mercator and polar projections while the regions observed by VIRTIS can presently be visualized only in Mercator projection. The Mercator projection is the standard map provided by Google. The polar projections are provided by NASA and have been developed to be used in combination with APIs provided by Google The whole project has been developed following the "open source" philosophy: the client-side code which handles the functioning of the web page is written in javascript; the server-side code which executes the searches for tracks or regions is written in PHP and the DB which undergoes the system is MySQL.

  11. Mars habitat

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The College of Engineering & Architecture at Prairie View A&M University has been participating in the NASA/USRA Advanced Design Program since 1986. The interdisciplinary nature of the program allowed the involvement of students and faculty throughout the College of Engineering & Architecture for the last five years. The research goal for the 1990-1991 year is to design a human habitat on Mars that can be used as a permanent base for 20 crew members. The research is being conducted by undergraduate students from the Department of Architecture.

  12. Mars Albedo

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These two views of Mars are derived from the MGS Thermal Emission Spectrometer (TES) measurements of global broadband (0.3 - 3.0 microns) visible and near-infrared reflectance, also known as albedo. The range of colors are in dimensionless units. The values are the ratio of the amount of electromagnetic energy reflected by the surface to the amount of energy incident upon it from the sun (larger values are brighter surfaces).

    The TES instrument was built by Santa Barbara Remote Sensing and is operated by Philip R. Christensen, of Arizona State University, Tempe, AZ.

  13. Thermal Performance of Capillary Pumped Loops Onboard Terra Spacecraft

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Ottenstein, Laura; Butler, Charles D.; Swanson, Theodore; Thies, Diane

    2004-01-01

    The Terra spacecraft is the flagship of NASA's Earth Science Enterprise. It provides global data on the state of atmosphere, land and oceans, as well as their interactions with solar radiation and one another. Three Terra instruments utilize Capillary Pumped Heat Transport System (CPHTS) for temperature control: Each CPHTS, consisting of two capillary pumped loops (CPLs) and several heat pipes and electrical heaters, is designed for instrument heat loads ranging from 25W to 264W. The working fluid is ammonia. Since the launch of the Terra spacecraft, each CPHTS has been providing a stable interface temperature specified by the instrument under all modes of spacecraft and instrument operations. The ability to change the CPHTS operating temperature upon demand while in service has also extended the useful life of one instrument. This paper describes the design and on-orbit performance of the CPHTS thermal systems.

  14. Mars Exploration Program and Mars Technology Program

    NASA Technical Reports Server (NTRS)

    Whetsel, C. W.

    2002-01-01

    The Mars Exploration Program and constituent Mars Technology Program are described. Current ongoing and future NASA-led missions are presented, including discussions of scientific accomplishments and objectives as well as technology validations accomplished and technological enablers for future missions.

  15. Evidence for volcanism in NW Ishtar Terra, Venus

    NASA Technical Reports Server (NTRS)

    Gaddis, L.; Greeley, Ronald

    1989-01-01

    Venera 15/16 radar data for an area in NW Ishtar Terra, Venus, show an area with moderate radar return and a smooth textured surface which embays low lying areas of the surrounding mountainous terrain. Although this unit may be an extension of the lava plains of Lakshmi Planum to the southeast, detailed study suggests a separate volcanic center in NW Ishtar Terra. Lakshmi Planum, on the Ishtar Terra highland, exhibits major volcanic and tectonic features. On the Venera radar image radar brightness is influenced by slope and roughness; radar-facing slopes (east-facing) and rough surfaces (approx. 8 cm average relief) are bright, while west-facing slopes and smooth surfaces are dark. A series of semi-circular features, apparently topographic depressions, do not conform in orientation to major structural trends in this region of NW Ishtar Terra. The large depression in NW Ishtar Terra is similar to the calderas of Colette and Sacajawea Paterae, as all three structures are large irregular depressions. NW Ishtar Terra appears to be the site of a volcanic center with a complex caldera structure, possibly more than one eruptive vent, and associated lobed flows at lower elevations. The morphologic similarity between this volcanic center and those of Colette and Sacajawea suggests that centralized eruptions have been the dominant form of volcanism in Ishtar. The location of this volcanic center at the intersection of two major compressional mountain belts and the large size of the calders (with an inferred larg/deep magma source) support a crustal thickening/melting rather than a hot-spot origin for these magmas.

  16. Visual and neurologic sequelae of methanol poisoning in Saudi Arabia

    PubMed Central

    Galvez-Ruiz, Alberto; Elkhamary, Sahar M.; Asghar, Nasira; Bosley, Thomas M.

    2015-01-01

    Objectives: To present the visual sequelae of methanol poisoning and to emphasize the characteristics of methanol exposure in the Kingdom of Saudi Arabia (KSA). Methods: A retrospective case series was carried out on 50 sequential patients with methanol poisoning seen at the King Khaled Eye Specialist Hospital and King Saud University Hospitals in Riyadh, KSA between 2008 and 2014. All patients were examined by a neuro-ophthalmologist at least one month after methanol intoxication. Results: All 50 patients were young or middle-aged males. All admitted to drinking unbranded alcohol within 2-3 days before profound or relatively profound, painless, bilateral visual loss. Mean visual acuity in this group was hand motions (logMAR 2.82; range 0.1 - 5.0) with some eye to eye variability within individuals. Worse visual acuity was correlated with advancing age (Pearson correlation: oculus dextrus [right eye] - 0.37, p=0.008; oculus sinister [left eye] - 0.36, p=0.011). All patients had optic atrophy bilaterally, and all tested patients had visual field defects. Tremors with or without rigidity were present in 12 patients, and 11 of 30 patients who had neuroimaging performed had evidence of putaminal necrosis. Conclusion: Methanol intoxication causes visual loss within 12-48 hours due to relatively severe, painless, bilateral optic nerve damage that may be somewhat variable between eyes, and is generally worse with advancing age. The coincidence of bilateral optic nerve damage and bilateral putaminal necrosis in a young or middle-aged male is very suspicious for methanol-induced damage. PMID:25935177

  17. Terra firma-forme dermatosis: Case Series and dermoscopic features.

    PubMed

    Abdel-Razek, Moheb M; Fathy, Hanan

    2015-10-01

    Terra firma-forme dermatosis (TFFD) is characterized by dirt-like skin lesions that disappear after rubbing with alcohol. We describe the dermoscopic features of TFFD before and after alcohol swabbing in six patients. All patients showed similar dermoscopic appearance with large polygonal plate-like brown scales arranged together giving a mosaic pattern. These features disappear completely after isopropyl alcohol swabbing of the lesions. In conclusion dermoscopy can assist in the evaluation of terra firma-forme dermatosis and the dermoscopic evaluation of other dirty dermatoses is recommended in the future to compare findings with TFFD. PMID:26632811

  18. NASA's Terra Spacecraft Measures Height of California Rim Fire Smoke Plumes

    Atmospheric Science Data Center

    2014-05-15

    ... NASA's Terra Spacecraft Measures Height of California Rim Fire Smoke Plumes     View ... - NASA's Terra Spacecraft Measures Height of California Rim Fire Smoke Plumes project:  MISR category:  ...

  19. Occurrence of indoor allergens in Saudi Arabia

    SciTech Connect

    Sorensen, H.; Gravesen, S.; Lind, P.; Schwartz, B.; Ashoor, A.A.; Maglad, S.

    1985-06-01

    Investigations on indoor airborne allergens in Saudi Arabia were performed by mold cultures and dust analyses by counter-current immunoelectrophoresis. Twenty fungal genera were isolated, with Aspergillus as the most often encountered. Most of the dust-bound fungi found are ubiquitous and common. Antibodies against Dermatophagoides pteronyssinus, cat- cow- and rat dander, and Cynodon dactylon pollen were used in the dust analyses. Animal antigens were found in five of the ten dust samples. House dust mites were extraordinarily rare. Pollen of Cynodon dactylon (Bermuda grass) was present in nearly all the samples, and in a concurrent clinical study this antigen was found to be the most common cause of perennial rhinitis.

  20. Assessing Volcanic Risk in Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Lindsay, Jan Marie; Rashad Moufti, Mohammed

    2014-08-01

    The Kingdom of Saudi Arabia has numerous large monogenetic volcanic fields, known locally as "harrats." The largest of these, Harrat Rahat (Figure 1), produced a basaltic fissure eruption in 1256 C.E. with lava flows traveling within 20 kilometers of the city Al-Madinah, which currently has a population of 1.5 million plus an additional 3 million pilgrims annually. With more than 950 visible vents and periodic seismic swarms, an understanding of the risk of future eruptions in this volcanic field is vital.

  1. Domestic water conservation potential in Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Abdulrazzak, Mohammed J.; Khan, Muhammad Z. A.

    1990-03-01

    Domestic water conservation in arid climates can result in efficient utilization of existing water supplies. The impacts of conservation measures such as the installation of water-saving devices, water metering and pricing schemes, water rationing and public awareness programs, strict plumbing codes, penalties for wasting water, programs designed to reduce leakage from public water lines and within the home, water-efficient landscaping, economic and ethical incentives are addressed in detail. Cost savings in arid climates, with particular reference to Saudi Arabia, in relation to some conservation techniques, are presented. Water conservation technology and tentative demonstration and implementation of water conservation programs are discussed.

  2. Quantitative interaction screen of telomeric repeat-containing RNA reveals novel TERRA regulators

    PubMed Central

    Scheibe, Marion; Arnoult, Nausica; Kappei, Dennis; Buchholz, Frank; Decottignies, Anabelle; Butter, Falk; Mann, Matthias

    2013-01-01

    Telomeres are actively transcribed into telomeric repeat-containing RNA (TERRA), which has been implicated in the regulation of telomere length and heterochromatin formation. Here, we applied quantitative mass spectrometry (MS)–based proteomics to obtain a high-confidence interactome of TERRA. Using SILAC-labeled nuclear cell lysates in an RNA pull-down experiment and two different salt conditions, we distinguished 115 proteins binding specifically to TERRA out of a large set of background binders. While TERRA binders identified in two previous studies showed little overlap, using quantitative mass spectrometry we obtained many candidates reported in these two studies. To test whether novel candidates found here are involved in TERRA regulation, we performed an esiRNA-based interference analysis for 15 of them. Knockdown of 10 genes encoding candidate proteins significantly affected total cellular levels of TERRA, and RNAi of five candidates perturbed TERRA recruitment to telomeres. Notably, depletion of SRRT/ARS2, involved in miRNA processing, up-regulated both total and telomere-bound TERRA. Conversely, knockdown of MORF4L2, a component of the NuA4 histone acetyltransferase complex, reduced TERRA levels both globally and for telomere-bound TERRA. We thus identified new proteins involved in the homeostasis and telomeric abundance of TERRA, extending our knowledge of TERRA regulation. PMID:23921659

  3. Mars Exploration Rovers: 4 Years on Mars

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2008-01-01

    This January, the Mars Exploration Rovers "Spirit" and "Opportunity" are starting their fifth year of exploring the surface of Mars, well over ten times their nominal 90-day design lifetime. This lecture discusses the Mars Exploration Rovers, presents the current mission status for the extended mission, some of the most results from the mission and how it is affecting our current view of Mars, and briefly presents the plans for the coming NASA missions to the surface of Mars and concepts for exploration with robots and humans into the next decade, and beyond.

  4. Mars Public Engagement Overview

    NASA Technical Reports Server (NTRS)

    Johnson, Christine

    2009-01-01

    This viewgraph presentation reviews the Mars public engagement goal to understand and protect our home planet, explore the Universe and search for life, and to inspire the next generation of explorers. Teacher workshops, robotics education, Mars student imaging and analysis programs, MARS Student Imaging Project (MSIP), Russian student participation, MARS museum visualization alliance, and commercialization concepts are all addressed in this project.

  5. Genesis and fluid source in Arabia crater mounds: mapping, fractal analysis, and impact simulations

    NASA Astrophysics Data System (ADS)

    Pozzobon, R.; Mazzarini, F.; Rossi, A.; Lucchetti, A.; Pondrelli, M.; Marinangeli, L.; Martellato, E.; Cremonese, G.; Massironi, M.

    2013-12-01

    Arabia Terra is dominated by heavily cratered terrains, and some peculiar landforms can be found mostly in craters interior. With high-resolution images from HiRISE (25 cm/px) and CTX (6 m/px) cameras pitted cones, mounds and knobs can be easily recognized. Those mounds are interpreted to have worked as pathways for subsurface fluid. It is commonly hypothesized that Arabia Terra is an area of past fluid activity, being crater central bulges a place of sulfate precipitation. In this work we investigate the presence, origin and timing of their formation as well as the the depth of the mounds fluid source. The spatial distribution of monogenic eruptive structures within volcanic areas on Earth has been linked to fracture systems that allowed an efficient hydraulic connection between surface and crustal or subcrustal magma reservoirs. Self-similarity in vent distribution is described by a power law distribution with fractal exponent D and defined over a range of lengths comprised between a lower limit (lower cutoff, Lco) and an upper limit (upper cutoff, Uco). On Earth, volcanic vents as well as mud volcanoes have shown that the Uco of their fractal distribution scales with the depth of pressurized fluid reservoirs. The same approach has been this applied to mounds mapped at Firsoff and Crommelin craters. 431 mounds were mapped on Firsoff Crater's floor, and 160 on Crommelin Crater's floor. The reslulting Uco for both craters are similar giving a source depth of 2.3 ×0.3 km from Firsoff Crater's ground floor and 2.6 ×0.5 km from Crommelin's floor. Hence it is possible to hypothesize a common regional-scale pressurized fluid level at 2.5 km of depth from craters floor. Morphogic and stratigraphical analyses of the high-resolution imagery and topography of those mounds allowed us to discern from actual mud volcano candidates and stratigraphic erosional remnants. We also studied the craters formation by simulating the impact with the hydrocode. We used iSALE shock code

  6. A new cucurbitacin from Picria fel-terrae.

    PubMed

    Zou, J-M; Wang, L-S; Ma, X-M; Guo, Y-J; Shi, R-B

    2006-06-01

    A new cucurbitacin, picfeltarraenone II (1) as well as four known cucurbitacins, picfeltarraegenin I (2), picfeltarraenin IA (3), picfeltarraenin IB (4), and picfeltarraenin IV (5), have been isolated and characterized from the whole plant of Picria fel-terrae. The purity of picfeltarraenin IA has been determined by TLC and HPLC. PMID:16864449

  7. FLASH_SSF_Terra-FM1_V3B

    Atmospheric Science Data Center

    2016-07-22

    ... FLASH_SSF_Terra-FM1_V3B Project Title:  CERES Discipline:  Clouds Radiation Budget ...   Reverb Tutorial Subset/Visualization Tool:  CERES Order Tool CERES Search and Subset Tool (HDF4 & netCDF) ...

  8. Genome Sequences of Gordonia terrae Phages Benczkowski14 and Katyusha

    PubMed Central

    Benczkowski, Matthew S.; Green, Daryn E.; Hwang, Melina; Kennedy, Bryan; Kocak, Bradley; Kruczek, Ellen; Lin, Leon; Moretti, Matthew L.; Onelangsy, Faith L.; Mezghani, Nadia; Milliken, Katherine A.; Toner, Chelsea L.; Thompson, Paige K.; Ulbrich, Megan C.; Furbee, Emily C.; Grubb, Sarah R.; Warner, Marcie H.; Montgomery, Matthew T.; Garlena, Rebecca A.; Russell, Daniel A.; Jacobs-Sera, Deborah; Hatfull, Graham F.

    2016-01-01

    Bacteriophages Katyusha and Benczkowski14 are newly isolated phages that infect Gordonia terrae 3612. Both have siphoviral morphologies with isometric heads and long tails (500 nm). The genomes are 75,380 bp long and closely related, and the tape measure genes (9 kbp) are among the largest to be identified. PMID:27340062

  9. Genome Sequences of Gordonia terrae Phages Benczkowski14 and Katyusha.

    PubMed

    Pope, Welkin H; Benczkowski, Matthew S; Green, Daryn E; Hwang, Melina; Kennedy, Bryan; Kocak, Bradley; Kruczek, Ellen; Lin, Leon; Moretti, Matthew L; Onelangsy, Faith L; Mezghani, Nadia; Milliken, Katherine A; Toner, Chelsea L; Thompson, Paige K; Ulbrich, Megan C; Furbee, Emily C; Grubb, Sarah R; Warner, Marcie H; Montgomery, Matthew T; Garlena, Rebecca A; Russell, Daniel A; Jacobs-Sera, Deborah; Hatfull, Graham F

    2016-01-01

    Bacteriophages Katyusha and Benczkowski14 are newly isolated phages that infect Gordonia terrae 3612. Both have siphoviral morphologies with isometric heads and long tails (500 nm). The genomes are 75,380 bp long and closely related, and the tape measure genes (9 kbp) are among the largest to be identified. PMID:27340062

  10. SITE TECHNOLOGY CAPSULE: TERRA-KLEEN SOLVENT EXTRACTION TECHNOLOGY

    EPA Science Inventory

    Remediation of PCBs in soils has been difficult to implement on a full-scale, cost-effective basis. The Terra-Kleen solvent extraction system has overcome many of the soil handling, contaminant removal, and regulatory restrictions that have made it difficult to implement a cost-e...

  11. 10 years of Terra Outreach over the Internet

    NASA Astrophysics Data System (ADS)

    Yuen, K.; Riebeek, H.; Chambers, L. H.

    2009-12-01

    1 Author Yuen, Karen JPL (818) 393-7716 2 Author Riebeek, Holli Sigma Space Corporation (department) at NASA Goddard Space Flight Center (Institution), Greenbelt, Maryland 3 Author Chambers, Lin NASA Abstract: Since launch, Terra has returned about 195 gigabytes (level 0) of data per day or 1 terabyte every 5 days. Few outlets were able to accommodate and quickly share that amount of information as well as the Internet. To honor the 10-year anniversary of the launch of Terra, we would like to highlight the education and outreach efforts of the Terra mission on the Internet and its reach to the science attentive public. The Internet or web has been the primary way of delivering Terra content to different groups- from formal and informal education to general public outreach. Through the years, many different web-based projects have been developed, and they were of service to a growing population of the science attentive public. One of Terra’s original EPO activities was the Earth Observatory. It was initially dedicated to telling the remote sensing story of Terra, but quickly grew to include science and imagery from other sensors. The web site allowed for collaboration across NASA centers, universities and other organizations by exchanging and sharing of story ideas, news and images. The award winning Earth Observatory helped pave the way for the more recently funded development of the Climate Change website. With its specific focus on climate change studies, once again, Terra stories and images are shared with an even more specific audience base. During the last 10 years, Terra as a mission has captured the imagination of the public through its visually stunning and artistically arresting images. With its five instruments of complementary but unique capabilities, the mission gave the world not just pretty pictures, but scientific data-based images. The world was able to see from space everything from calving icebergs to volcanic eruption plumes and the eye of a

  12. Multitemporal observations of sugarcane by TerraSAR-X images.

    PubMed

    Baghdadi, Nicolas; Cresson, Rémi; Todoroff, Pierre; Moinet, Soizic

    2010-01-01

    The objective of this study is to investigate the potential of TerraSAR-X (X-band) in monitoring sugarcane growth on Reunion Island (located in the Indian Ocean). Multi-temporal TerraSAR data acquired at various incidence angles (17°, 31°, 37°, 47°, 58°) and polarizations (HH, HV, VV) were analyzed in order to study the behaviour of SAR (synthetic aperture radar) signal as a function of sugarcane height and NDVI (Normalized Difference Vegetation Index). The potential of TerraSAR for mapping the sugarcane harvest was also studied. Radar signal increased quickly with crop height until a threshold height, which depended on polarization and incidence angle. Beyond this threshold, the signal increased only slightly, remained constant, or even decreased. The threshold height is slightly higher with cross polarization and higher incidence angles (47° in comparison with 17° and 31°). Results also showed that the co-polarizations channels (HH and VV) were well correlated. High correlation between SAR signal and NDVI calculated from SPOT-4/5 images was observed. TerraSAR data showed that after strong rains the soil contribution to the backscattering of sugarcane fields can be important for canes with heights of terminal visible dewlap (htvd) less than 50 cm (total cane heights around 155 cm). This increase in radar signal after strong rains could involve an ambiguity between young and mature canes. Indeed, the radar signal on TerraSAR images acquired in wet soil conditions could be of the same order for fields recently harvested and mature sugarcane fields, making difficult the detection of cuts. Finally, TerraSAR data at high spatial resolution were shown to be useful for monitoring sugarcane harvest when the fields are of small size or when the cut is spread out in time. The comparison between incidence angles of 17°, 37° and 58° shows that 37° is more suitable to monitor the sugarcane harvest. The cut is easily detectable on TerraSAR images for data acquired

  13. Multitemporal Observations of Sugarcane by TerraSAR-X Images

    PubMed Central

    Baghdadi, Nicolas; Cresson, Rémi; Todoroff, Pierre; Moinet, Soizic

    2010-01-01

    The objective of this study is to investigate the potential of TerraSAR-X (X-band) in monitoring sugarcane growth on Reunion Island (located in the Indian Ocean). Multi-temporal TerraSAR data acquired at various incidence angles (17°, 31°, 37°, 47°, 58°) and polarizations (HH, HV, VV) were analyzed in order to study the behaviour of SAR (synthetic aperture radar) signal as a function of sugarcane height and NDVI (Normalized Difference Vegetation Index). The potential of TerraSAR for mapping the sugarcane harvest was also studied. Radar signal increased quickly with crop height until a threshold height, which depended on polarization and incidence angle. Beyond this threshold, the signal increased only slightly, remained constant, or even decreased. The threshold height is slightly higher with cross polarization and higher incidence angles (47° in comparison with 17° and 31°). Results also showed that the co-polarizations channels (HH and VV) were well correlated. High correlation between SAR signal and NDVI calculated from SPOT-4/5 images was observed. TerraSAR data showed that after strong rains the soil contribution to the backscattering of sugarcane fields can be important for canes with heights of terminal visible dewlap (htvd) less than 50 cm (total cane heights around 155 cm). This increase in radar signal after strong rains could involve an ambiguity between young and mature canes. Indeed, the radar signal on TerraSAR images acquired in wet soil conditions could be of the same order for fields recently harvested and mature sugarcane fields, making difficult the detection of cuts. Finally, TerraSAR data at high spatial resolution were shown to be useful for monitoring sugarcane harvest when the fields are of small size or when the cut is spread out in time. The comparison between incidence angles of 17°, 37° and 58° shows that 37° is more suitable to monitor the sugarcane harvest. The cut is easily detectable on TerraSAR images for data acquired

  14. Mars Observer Laser Altimeter

    NASA Technical Reports Server (NTRS)

    Zuber, Maria T.

    1997-01-01

    The objective of this study was to support the rebuild and implementation of the Mars Orbiter Laser Aftimeter (MOLA) investigation and to perform scientific analysis of current Mars data relevant to the future investigation. The instrument is part of the payload of the NASA Mars Global Surveyor (MGS) mission. The instrument is a rebuild of the Mars Observer Laser Altimeter that was originally flown on the ill-fated Mars Observer mission.

  15. Mars Observer Lecture: Mars Orbit Insertion

    NASA Technical Reports Server (NTRS)

    Dodd, Suzanne R. (Personal Name)

    1993-01-01

    The Mars Observer mission spacecraft was primarily designed for exploring Mars and the Martian environment. The Mars Observer was launched on September 25, 1992. The spacecraft was lost in the vicinity of Mars on August 21, 1993 when the spacecraft began its maneuvering sequence for Martian orbital insertion. This videotape shows a lecture by Suzanne R. Dodd, the Mission Planning Team Chief for the Mars Observer Project. Ms Dodd begins with a brief overview of the mission and the timeline from the launch to orbital insertion. Ms Dodd then reviews slides showing the trajectory of the spacecraft on its trip to Mars. Slides of the spacecraft being constructed are also shown. She then discusses the Mars orbit insertion and the events that will occur to move the spacecraft from the capture orbit into a mapping orbit. During the trip to Mars, scientists at JPL had devised a new strategy, called Power In that would allow for an earlier insertion into the mapping orbit. The talk summarizes this strategy, showing on a slide the planned transition orbits. There are shots of the Martian moon, Phobos, taken from the Viking spacecraft, as Ms Dodd explains that the trajectory will allow the orbiter to make new observations of that moon. She also explains the required steps to prepare for mapping after the spacecraft has achieved the mapping orbit around Mars. The lecture ends with a picture of Mars from the Observer on its approach to the planet.

  16. Global Color Views of Mars

    NASA Technical Reports Server (NTRS)

    1997-01-01

    About 1000 Viking Orbiter red- and violet-filter images have been processed to provide global color coverage of Mars at a scale of 1 km/pixel. Individual image frames acquired during a single spacecraft revolution were first processed through radiometric calibration, cosmetic cleanup, geometric control, reprojection, and mosaicing. We have produced a total of 57 'single-rev' mosaics. All of the mosaics are geometrically tied to the Mars Digital Image Mosaic, a black-and-white base map with a scale of 231 m/pixel. We selected a subset of single-rev mosaics that provide the best global coverage (least atmospheric obscuration and seasonal frost); photometric normalization was applied to remove atmospheric effects and normalize the variations in illumination and viewing angles. Finally, these normalized mosaics were combined into global mosaics. Global coverage is about 98% complete in the red-filter mosaic and 95% complete in the violet-filter mosaic. Gaps were filled by interpolation. A green-filter image was synthesized from an average of the red and violet filter data to complete a 3-color set. The Viking Orbiters acquired actual green-filter images for only about half of the Martian surface. The final mosaic has been reprojected into several map projections. The orthographic view shown here is centered at 20 degrees latitude and 60 degrees longitude. The orthographic view is most like the view seen by a distant observer looking through a telescope. The color balance selected for these images was designed to be close to natural color for the bright reddish regions such as Tharsis and Arabia, but the data have been 'stretched' such that the relatively dark regions appear darker and less reddish that their natural appearance. This stretching allows us to better see the color and brightness variations on Mars, which are related to the composition or physical structure of the surface materials, which include volcanic lava flows, wind- and water-deposited sedimentary

  17. Can we expect habitable niches for cyanobacteria on Mars?

    NASA Astrophysics Data System (ADS)

    de Vera, Jean-Pierre Paul; Lorek, Andreas; Koncz, Alexander; Billi, Daniela; Baqué, Mickael; Leya, Thomas; Brown, Sarah; Cockell, Charles

    2013-04-01

    The most resistant cyanobacteria can be found in tropic deserts and in polar and alpine habitats. The reason for their resistance can be explained by their occurrence in intensely irradiated, very dry and/or cold environments which are supposed to be as close as possible similar to Martian surface conditions. A systematically approach comparing measurements on photosynthetic activity of cyanobacteria in relation to measured environmental parameters obtained in Mars analog field sites with data collected from space exposed samples or during Mars simulation experiments will show differences and common results after analyzing the investigated organisms. Some of the investigated species are foreseen to be exposed during the next ESA-space-exposure experiment BIOMEX either directly to real space conditions on space exposure platforms like EXPOSE-R2 on the International Space Station or to Mars simulation conditions in a Mars simulation chamber. Some of the species were still exposed to both of the extreme environmental conditions and some of the results will be presented and might serve for future investigations as references. We will emphasize that in parallel monitoring of environmental parameters on Mars analog field sites was performed as well as partly in space and in the simulation chambers. This experimental combination might help to get a better impression about the influence of each of the tested parameters on metabolic activity of the tested cyanobacteria in complete different planetary environments comparing characterized habitats on our home planet Earth with those we might expect according to recently observed data on Mars. The outcome of this work could be relevant to classify e.g. Mars as a habitable planet by a new combination of different experimental and biological approaches and to evaluate and discuss the likelihood of terra forming Mars in the far future.

  18. Mantle flow beneath Arabia offset from the opening Red Sea

    NASA Astrophysics Data System (ADS)

    Chang, Sung-Joon; Merino, Miguel; Van der Lee, Suzan; Stein, Seth; Stein, Carol A.

    2011-02-01

    Continental rifting involves a poorly understood sequence of lithospheric stretching, volcanism, and mantle flow that evolves to seafloor spreading. We present new insight from inversion of seismic traveltimes and waveforms beneath Arabia and surroundings. Low velocities occur beneath the southern Red Sea and Gulf of Aden, consistent with active spreading. However, hot material extends not below the northern Red Sea, but is offset eastward beneath Arabia, showing mantle flow from the Afar hotspot. The location of this channel beneath volcanic rocks erupted since rifting began 30 million years ago indicates that flow moves with Arabia. We propose that the absence of seafloor spreading in the northern Red Sea reflects the offset flow. This geometry may evolve to spreading in the Northern Red Sea, rifting of Arabia, or both. This situation has aspects of both active and passive rifting, showing that both can occur before coalescing to seafloor spreading.

  19. The Arabia-India plate boundary unveiled

    NASA Astrophysics Data System (ADS)

    Fournier, M.; Chamot-Rooke, N. R.; Rodriguez, M.; Petit, C.; Huchon, P.; Beslier, M.; Hazard, B.

    2009-12-01

    Since the advent of Plate Tectonics, tectonic plate boundaries were explored on land as at sea for search of active faults where the destructive energy of earthquakes is released. Yet, some plate boundaries, less active or considered as less dangerous to humankind, escaped general attention and remained unknown to a large extent. Among them, the boundary between two major tectonic plates: Arabia and India. The Arabia-India motion is currently accommodated along the Owen Fracture Zone (OFZ) in the NW Indian Ocean, which connects the spreading centers of the Sheba and Carlsberg ridge system to the Makran subduction zone. We recently surveyed this fracture zone onboard the R/V Beautemps-Beaupré (Owen Cruise, March 2009) using a high-resolution deep-water multibeam echo-sounder. Bathymetric data reveal a spectacular submarine fault system running over a distance of 800 km between the Arabia-India-Somalia triple junction to the south and the Dalrymple Trough to the north. The morphology of the active faults is well preserved on the seafloor where fault scarps can be followed over hundreds of kilometres. The surficial trace of the faults is not obscured by the sediments of the aggrading deep-sea fan of the Indus River. The fault system is segmented in five main segments connected by pull apart basins. The length of the individual, apparently uninterrupted, segments is between 100 km and 220 km. The largest pull-apart basin at the latitude 20°N (20°N-Basin) corresponds to a right step-over of about 12 km between two fault segments. The 20°N-Basin is bounded by a normal fault scarp with a throw of 450-500 m. Numerous minor normal faults cutting the floor of the basin attest to recent activity. The 20°N-Basin is directly supplied in turbidity-current deposits by an active channel of the Indus fan. The preservation of tectonic features indicates that the dip-slip motion has exceeded the rate of burial by sediments. Some compressional structures are also deduced from

  20. Climate change and animals in Saudi Arabia

    PubMed Central

    Williams, Joseph B.; Shobrak, Mohammed; Wilms, Thomas M.; Arif, Ibrahim A.; Khan, Haseeb A.

    2011-01-01

    Global warming is occurring at an alarming rate and predictions are that air temperature (Ta) will continue to increase during this century. Increases in Ta as a result of unabated production of greenhouse gases in our atmosphere pose a threat to the distribution and abundance of wildlife populations worldwide. Although all the animals worldwide will likely be affected by global warming, diurnal animals in the deserts will be particularly threatened in the future because Tas are already high, and animals have limited access to water. It is expected that Saudi Arabia will experience a 3–5 °C in Ta over the next century. For predicting the consequences of global warming for animals, it is important to understand how individual species will respond to higher air temperatures. We think that populations will not have sufficient time to make evolutionary adjustments to higher Ta, and therefore they will be forced to alter their distribution patterns, or make phenotypic adjustments in their ability to cope with high Ta. This report examines how increases in Ta might affect body temperature (Tb) in the animals of arid regions. We chose three taxonomic groups, mammals, birds, and reptiles (Arabian oryx, Arabian spiny-tailed lizard, vultures, and hoopoe larks) from Saudi Arabia, an area in which Ta often reaches 45 °C during midday in summer. When Ta exceeds Tb, animals must resort to behavioral and physiological methods to control their Tb; failure to do so results in death. The observations of this study show that in many cases Tb is already close to the upper lethal limit of around 47° C in these species and therefore allowing their Tb to increase as Ta increases are not an option. We conclude that global warming will have a detrimental impact on a wide range of desert animals, but in reality we know little about the ability of most animals to cope with change in Ta. The data presented should serve as base-line information on Tb of animals in the Kingdom for

  1. Climate change and animals in Saudi Arabia.

    PubMed

    Williams, Joseph B; Shobrak, Mohammed; Wilms, Thomas M; Arif, Ibrahim A; Khan, Haseeb A

    2012-04-01

    Global warming is occurring at an alarming rate and predictions are that air temperature (T a) will continue to increase during this century. Increases in T a as a result of unabated production of greenhouse gases in our atmosphere pose a threat to the distribution and abundance of wildlife populations worldwide. Although all the animals worldwide will likely be affected by global warming, diurnal animals in the deserts will be particularly threatened in the future because T as are already high, and animals have limited access to water. It is expected that Saudi Arabia will experience a 3-5 °C in T a over the next century. For predicting the consequences of global warming for animals, it is important to understand how individual species will respond to higher air temperatures. We think that populations will not have sufficient time to make evolutionary adjustments to higher T a, and therefore they will be forced to alter their distribution patterns, or make phenotypic adjustments in their ability to cope with high T a. This report examines how increases in T a might affect body temperature (T b) in the animals of arid regions. We chose three taxonomic groups, mammals, birds, and reptiles (Arabian oryx, Arabian spiny-tailed lizard, vultures, and hoopoe larks) from Saudi Arabia, an area in which T a often reaches 45 °C during midday in summer. When T a exceeds T b, animals must resort to behavioral and physiological methods to control their T b; failure to do so results in death. The observations of this study show that in many cases T b is already close to the upper lethal limit of around 47° C in these species and therefore allowing their T b to increase as T a increases are not an option. We conclude that global warming will have a detrimental impact on a wide range of desert animals, but in reality we know little about the ability of most animals to cope with change in T a. The data presented should serve as base-line information on T b of animals in the

  2. Evidence for Recent Liquid Water on Mars

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Gullies eroded into the wall of a meteor impact crater in Noachis Terra. This high resolution view (top left) from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) shows channels and associated aprons of debris that are interpreted to have formed by groundwater seepage, surface runoff, and debris flow. The lack of small craters superimposed on the channels and apron deposits indicates that these features are geologically young. It is possible that these gullies indicate that liquid water is present within the martian subsurface today. The MOC image was acquired on September 28, 1999. The scene covers an area approximately 3 kilometers (1.9 miles) wide by 6.7 km (4.1 mi) high (note, the aspect ratio is 1.5 to 1.0). Sunlight illuminates this area from the upper left. The image is located near 54.8S, 342.5W. The context image (above) shows the location of the MOC image on the south-facing wall of an impact crater approximately 20 kilometers (12 miles) in diameter. The context picture was obtained by the Viking 1 orbiter in 1980 and is illuminated from the upper left. The large mound on the floor of the crater in the context view is a sand dune field. The Mars Orbiter Camera high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s. A brief description of how the color was generated: The MOC narrow angle camera only takes grayscale (black and white) pictures. To create the color versions seen here, we have taken much lower resolution red and blue images acquired by the MOC's wide angle cameras, and by the Viking Orbiter cameras in the 1970s, synthesized a green image by averaging red and blue, and created a pallete of colors that represent the range of colors on Mars. We then use a relationship that correlates color and brightness to assign a color to each gray level. This is only a crude approximation of

  3. Mars scouts: an overview

    NASA Technical Reports Server (NTRS)

    Matousek, S.

    2001-01-01

    The Mars program institutes the Mars Scout Missions in order to address science goals in the program not otherwise covered in the baseline Mars plan. Mars Scout Missions will be Principle-Investigator (PI) led science missions. Analogous to the Discovery Program, PI led investigations optimize the use of limited resources to accomplish the best focused science and allow the flexibility to quickly respond to discoveries at Mars. Scout missions also require unique investments in technology and reliance upon Mars-based infrastructure such as telecom relay orbiters.

  4. Mars Orbiter Laser Altimeter

    NASA Technical Reports Server (NTRS)

    Zuber, Maria T.

    1997-01-01

    The objective of this study was to support the rebuild and implementation of the Mars Orbiter Laser Altimeter (MOLA) investigation and to perform scientific analysis of current Mars data relevant to the investigation. The instrument is part of the payload of the NASA Mars Global Surveyor (MGS) mission. The instrument is a rebuild of the Mars Observer Laser Altimeter that was originally flown on the ill-fated Mars Observer mission. The instrument is currently in orbit around Mars and has so far returned remarkable data.

  5. Mars integrated transportation system multistage Mars mission

    NASA Technical Reports Server (NTRS)

    1991-01-01

    In accordance with the objective of the Mars Integrated Transport System (MITS) program, the Multistage Mars Mission (MSMM) design team developed a profile for a manned mission to Mars. The purpose of the multistage mission is to send a crew of five astronauts to the martian surface by the year 2019. The mission continues man's eternal quest for exploration of new frontiers. This mission has a scheduled duration of 426 days that includes experimentation en route as well as surface exploration and experimentation. The MSMM is also designed as a foundation for a continuing program leading to the colonization of the planet Mars.

  6. The dynamic nature and spectral characteristics of low-albedo slope streaks on Mars and their possible hydrologic implications

    NASA Astrophysics Data System (ADS)

    Mushkin, A.; Stillman, D. E.; Gillespie, A. R.; Montgomery, D. R.; Schreiber, B. C.; Hibbitts, C.

    2014-12-01

    Low-albedo down-slope streaks that form repeatedly within weekly time-scales and subsequently fade over seasonal to decadal periods are commonly observed in the tropical and mid-latitudes of Mars. 'Dry' mass-wasting processes vs. 'wet' modification of the surface by aqueous phases are the mechanisms typically considered to explain their formation. Recently, high frequency HiRISE image time-series of seasonal recurrence, incremental growth and fading of small (meter-decameter scale) slope streaks, also termed 'recurring slope lineae' (RSL), have been presented in support of a 'wet' origin likely associated with brine seepage. Here, we present new results that demonstrate comparable recurrence, incremental growth and fading characteristics over yearly time-scales for decameter-kilometer scale low-albedo slope-streaks in Lycus Sulci, Amazonis Planitia and Arabia Terra. These dynamic characteristics support the previous association of low-albedo slope streaks with brine seepage based on their geomorphic and spectral relations with surrounding unaffected slopes. Low-albedo slope streaks are typically not associated with detectable erosion or terminal, down-slope depositional activity at the resolution of 25 cm/pixel HiRISE images. CRISM observations consistently indicate that darkened slope-streak surfaces are spectrally enriched in FeOx and are void of detectable water/ice spectral absorption bands. Thus, the liquid seeps considered for the formation of meter to kilometer scale slope streaks are likely low-volume transient events that evaporate and/or freeze and sublime leaving behind a meta-stable dry precipitate that 'stains' the surface dark and may provide insights into the possible composition of such brines. Slope streak formation through a 'wet' brine seepage mechanism supports the possible presence of pressurized sub-surface aquifers that may be released via faults or cracks able to produce recurring transient discharge events during favorably warm daily

  7. Volatile-rich Crater Interior Deposits in the Polar Regions of Mars: Evidence for Ice Cap Advance and Retreat

    NASA Technical Reports Server (NTRS)

    Russell, Patrick S.; Head, James W.; Hecht, Michael H.

    2003-01-01

    Many craters on Mars are partially filled by distinctive material emplaced by post-impact processes. This crater fill material is an interior mound which is generally separated from the walls of the crater by a trough that may be continuous along the crater circumference (i.e. a ring-shaped trough), or which may only partially contact the crater walls (i.e. a crescent-shaped trough). The fill deposit is frequently offset from the crater center and may be asymmetric in plan view. Populations of such craters include those in the circum-south polar cap region, in Arabia Terra, associated with the Medusae Fossae Formation, and in the northern lowlands proximal to the north polar cap. We focus on those craters in circumpolar regions and assess their relationship to polar cap advance and retreat, especially the possibility that fill material represents remnants of a formerly larger contiguous cap. Volatile-rich deposits have the property of being modifiable by the local stability of the solid volatile, which is governed by local energy balance. Here we test the hypothesis that asymmetries in volatile fill shape, profile, and center-location within a crater result from asymmetries in local energy balance within the crater, due mainly to variation of solar insolation and radiative effects of the crater walls over the crater interior. Model profiles of crater fill are compared with MOLA topographic profiles to assess this hypothesis. If asymmetry in morphology and location of crater fill are consistent with radiative-dominated asymmetries in energy budget within the crater, then 1) the volatile-rich composition of the fill is supported (this process should not be effective at shaping volcanic or sedimentary deposits), and 2) the dominant factor determining the observed shape of volatile-rich crater fill is the local radiative energy budget (and erosive processes such as eolian deflation are secondary or unnecessary). We also use a geographic and energy model approach to

  8. The Paleozoic petroleum geology of central Arabia

    SciTech Connect

    McGillivray, J.G.; Husseini, M.I. )

    1991-08-01

    Recent exploratory drilling in central Saudi Arabia indicates that all the geological elements of a major petroleum basin are present in this province. Several Paleozoic siliciclastic sequences which were deposited along the stable Arabian margin of Gondwanaland constitute excellent reservoirs. The identified reservoir targets include the Cambrian-Ordovician Saq Formation, Upper Ordovician-Lower Silurian glaciogenic clastics of the Sarah and Zarqa formations, and both fluvial and shallow marine sandstones of the Permian-Carboniferous Unayzah Formation. The source rock is a widespread organic-rich shale which was deposited during the regional deglaciation in the earliest Silurian. Migration occurred vertically along faults and/or updip from the regional Qusaiba shale subcrop through the reservoirs. Interbedded upper Permian shales and evaporites form the basal sequence of a major carbonate transgression and provide a capping seal. The traps are broad, low-relief, fault-generated structures which developed primarily during the Triassic.

  9. The pharmacoeconomic picture in Saudi Arabia.

    PubMed

    Alkhenizan, Abdullah

    2014-08-01

    Saudi Arabia is the largest country in the region and it is the largest oil producing country in the world. It is one of the few countries in the world which was not affected significantly by the global economic crisis. Health care spending is led mainly by governmental expenditure. Private sector share of the health care services is supported by the government and increasing. The demands for pharmaceutical products, medical devices and health care services is fueled by the rapidly growing population and the wide spread of chronic diseases. Publications and expertise in the field of pharmacoeconomics is scarce within the country. There is an urgent need to establish a national center for pharmacoeconomics to lead the country efforts in controlling the cost of health care services. Such a center is needed to promote pharmacoeconomics research and train health care professionals in this field. PMID:24953076

  10. Self-medication in Central Saudi Arabia

    PubMed Central

    Aljadhey, Hisham; Assiri, Ghada A.; Mahmoud, Mansour A.; Al-Aqeel, Sinaa; Murray, Michael

    2015-01-01

    Objectives: To determine the prevalence of self-medication and assess the knowledge, attitudes, and perception of consumers toward self-medication. Methods: This cross-sectional survey was conducted over 4 weeks in May 2011 in Riyadh city, Kingdom of Saudi Arabia. Community pharmacies within 5 areas of the city (North, South, West, East, and Middle) were randomly selected for the study. All consumers were approached to participate in the study, with the exception of those buying cosmetic and medicinal equipments. A validated self-administered questionnaire was used to collect the data. Results: A total of 538 out of 707 consumers attending community pharmacies in Riyadh city, agreed to participate in the study. Most responders were male (73%), 23-33 years old (35%), and college graduates (42%). A total of 285 medications were bought without a prescription. Of these, 149 (49%) medications should be dispensed by prescription only, and 155 (51%) were over the counter medications. The most common prescription medications dispensed without prescriptions were antibiotics (22%) and analgesics/antipyretics (19%). The most common reasons for buying medications without a prescription were that the symptoms were too minor to visit a doctor (54%), time saving (40%), and minor illnesses for which the participants knew the required treatment (40%). Overall, most participants had poor knowledge, and negative perceptions regarding self-medication. More than 68% of participants did not know whether the medicine they bought is a prescription-only or over the counter medication. Conclusion: Irresponsible self-medication is common in Saudi Arabia. Future studies should focus on improving the consumers’ awareness of self-medication and the proper use of medications. PMID:25737176

  11. Firearm fatalities in Dammam, Saudi Arabia.

    PubMed

    Al Madni, Osama; Kharosha, Magdy Abdel Azim; Shotar, Ali M

    2008-07-01

    This paper provides a database representing injury mortality in Dammam, Saudi Arabia, with the aim of establishing a system which will record information about the incidence of such deaths, identify new trends and give priority to violence prevention. The retrospective study was carried out on 64 fatalities from gunfire injuries at the Forensic Medicine Centre in Dammam, Saudi Arabia during the period from January 2002 - December 2006. The deaths included 55 cases of homicide, seven cases of suicide and two accidental shootings. Twenty-six victims were aged between 16-30 years and 24 victims were between 31-45 years. Fifty-nine of the cases were male. A handgun was the weapon used in 49 cases. The most common sites for the firearm entrance wounds were the head (45 cases) and the chest (35 cases). In the majority of cases (56.3%) a single shot was fired while in 15.6% of cases there were two shots. In 51.5% of cases no bullet was recovered from the body while a single bullet was recovered in 31.5% and two bullets in 6.2% of the cases. Distant range fire was observed in 65.6% of cases. Exit wounds were found on the head in 36.7% and on the chest in 28.7% of cases. The majority of victims were young males living in urban areas. This result should help in forming a strategy to improve the livelihoods of this group. The low incidence of alcohol abuse (one case, 1.56%) and only three cases (4.68%) of amphetamine abuse is significant. PMID:18754211

  12. Partially-Exhumed Crater in Northern Terra Meridiani: Mosaic of M04-01289, E17-01676, and M21-01646

    NASA Technical Reports Server (NTRS)

    2002-01-01

    MGS MOC Release No. MOC2-316, 8 August 2002 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images have shown time and again that the geology and history of Mars is complex. These two pictures show different views of a circular feature in northern Terra Meridiani at 2.3oN, 356.6oW. The first is a mosaic of 3 MOC narrow angle images acquired in August 1999, November 2000, and June 2002. The black area is a gap in coverage resulting from data lost after transmission from Mars to Earth. The second picture is a stereo ('3-D') anaglyph of a portion of the same circular feature. It has been rotated 90o clockwise to show the stereo effect that results from combining the August 1999 image, which was taken while the spacecraft was pointed nadir (straight down) and the June 2002 image, taken with the spacecraft pointing backwards about 16o (i.e., MGS Relay-16 orientation). The anaglyph should be viewed with '3-D' glasses (red in left eye, blue in the right). The circular feature was once an impact crater. The crater was 2.6 km (1.6 mi) across, about 2.6 times larger than the famous Meteor Crater in northern Arizona. Terra Meridiani, like northern Arizona, is a region of vast exposures of layered sedimentary rock. Like the crater in Arizona, this one was formed by a meteor that impacted a layered rock substrate. Later, this crater was filled and completely buried under more than 100 m (more than 327 ft) of additional layered sediment. The sediment hardened to become rock. Later still, the rock was eroded away--by processes unknown (perhaps wind)--to re-expose the buried crater. The crater today remains mostly filled with sediment, its present rim standing only about 40 m (130 ft) above its surroundings.

  13. How to create a Terra Harvest compliant plug-in

    NASA Astrophysics Data System (ADS)

    Klawon, Kevin; Gold, Josh; Marcucci, Nicholas

    2012-06-01

    The DIA wants to create an UGS controller that is interoperable across all controller platforms, capable of easily adding new sensors, radios, and processes, etc., as well as backward compatibility with existing UGS systems. To achieve this, the defined Terra Harvest standard is based on the latest Java JRE 1.6 and an OSGI platform. OSGI is an extensible framework that provides a modularized environment that allows functionality to be deployed in "bundles". These bundles can publish, discover, and share services available from other bundles or bundles provided by the controller core. This paper will give you architectural overview and then show you how to use the THOSE SDK to develop and deploy a bundle for your asset, communications device, or algorithm using OSGI and the Terra Harvest Standard.

  14. Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus

    NASA Technical Reports Server (NTRS)

    Kumar, P. Senthil; Head, James W., III

    2009-01-01

    Geological mapping of the V-56 quadrangle (Fig. 1) reveals various tectonic and volcanic features and processes in Lada Terra that consist of tesserae, regional extensional belts, coronae, volcanic plains and impact craters. This study aims to map the spatial distribution of different material units, deformational features or lineament patterns and impact crater materials. In addition, we also establish the relative age relationships (e.g., overlapping or cross-cutting relationship) between them, in order to reconstruct the geologic history. Basically, this quadrangle addresses how coronae evolved in association with regional extensional belts, in addition to evolution of tesserae, regional plains and impact craters, which are also significant geological units of Lada Terra.

  15. Summary of Terra and Aqua MODIS Long-Term Performance

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong (Jack); Wenny, Brian N.; Angal, Amit; Barnes, William; Salomonson, Vincent

    2011-01-01

    Since launch in December 1999, the MODIS ProtoFlight Model (PFM) onboard the Terra spacecraft has successfully operated for more than 11 years. Its Flight Model (FM) onboard the Aqua spacecraft, launched in May 2002, has also successfully operated for over 9 years. MODIS observations are made in 36 spectral bands at three nadir spatial resolutions and are calibrated and characterized regularly by a set of on-board calibrators (OBC). Nearly 40 science products, supporting a variety of land, ocean, and atmospheric applications, are continuously derived from the calibrated reflectances and radiances of each MODIS instrument and widely distributed to the world-wide user community. Following an overview of MODIS instrument operation and calibration activities, this paper provides a summary of both Terra and Aqua MODIS long-term performance. Special considerations that are critical to maintaining MODIS data quality and beneficial for future missions are also discussed.

  16. The TerraSAR-L Interferometric Mission Objectives

    NASA Astrophysics Data System (ADS)

    Zink, M.

    2004-06-01

    TerraSAR-L is the new imaging radar mission of the European Space Agency. The platform, based on the novel Snapdragon concept, is built around the active phase array antenna of the L-band Synthetic Aperture Radar (SAR). Specification of the L-SAR has been guided by careful analysis of the product requirements resulting in a robust baseline design with considerable margins. Besides having a commercial role for the provision of geo-information products, TerraSAR-L will contribute to the Global Monitoring for Environment and Security (GMES) initiative and serve the scientific user community. Interferometry (INSAR) is a key element behind a number of mission objectives. A L-band SAR in a 14-day repeat orbit is an ideal sensor for solid earth applications (earth quake and volcano monitoring, landslides and subsidence) relying on differential interferometry. L-band penetration of vegetation cover facilitates these applications also over vegetated surfaces. Because of the high coherence, L-band is also the preferred frequency for monitoring ice sheet and glacier dynamics. Highly accurate orbit control (orbital tube <100m) and special wideband INSAR modes are required to support these applications globally and systematically. Precise burst synchronisation enables repeat-pass ScanSAR interferometry and global coverage within the short repeat cycle. A feasibility study into cartwheel constellations flying in close formation with TerraSAR-L revealed the potential for generating Digital Elevation Models (DEMs) of unprecedented quality (2m relative height accuracy @ 12m posting). The TerraSAR-L operations strategy is based on a long-term systematic and repetitive acquisition scenario to ensure consistent data archives and to maximise the exploitation of this very powerful SAR system.

  17. Eastern Ishtar Terra: Tectonic evolution derived from recognized features

    NASA Technical Reports Server (NTRS)

    Vorderbruegge, R. W.; Head, James W.

    1989-01-01

    Previous analyses have recognized several styles and orientations of compressional deformation, crustal convergence, and crustal thickening in Eastern Ishtar Terra. An east to west sense of crustal convergence through small scale folding, thrusting, and buckling is reflected in the high topography and ridge-and-valley morphology of Maxwell Montes and the adjacent portion of Fortuna Tessera. This east to west convergence was accompanied by up to 1000 km of lateral motion and large scale strike-slip faulting within two converging shear zones which has resulted in the present morphology of Maxwell Montes. A more northeast to southwest sense of convergence through large scale buckling and imbrication is reflected in large, northwest-trending scarps along the entire northern boundary of Ishtar Terra, with up to 2 km of relief present at many of the scarps. It was previously suggested that both styles of compression have occurred at the expense of pre-existing tessera regions which have then been overprinted by the latest convergence event. The difference in style is attributed mostly to differences in the properties of the crust converging with the tessera blocks. If one, presumably thick, tessera block converges with another tessera region, then the widespread, distributed style of deformation occurs, as observed in western Fortuna Tessera. However, if relatively thin crust (such as suggested for the North Polar Plains converges with thicker tessera regions, then localized deformation occurs, as reflected in the scarps along Northern Ishtar Terra. The purpose is to identify the types of features observed in Eastern Ishtar Terra. Their potential temporal and spatial relationships, is described, possible origins for them is suggested, and how the interpretation of some of these features has led to the multiple-style tectonic evolution model described is shown.

  18. Genome Sequences of Gordonia terrae Bacteriophages Phinally and Vivi2

    PubMed Central

    Anderson, Kaitlyn C.; Arora, Charu; Bortz, Michael E.; Burnet, George; Conover, David H.; D’Incau, Gina M.; Ghobrial, Jonathan A.; Jonas, Audrey L.; Migdal, Emily J.; Rote, Nicole L.; German, Brian A.; McDonnell, Jill E.; Mezghani, Nadia; Schafer, Claire E.; Thompson, Paige K.; Ulbrich, Megan C.; Yu, Victor J.; Furbee, Emily C.; Grubb, Sarah R.; Warner, Marcie H.; Montgomery, Matthew T.; Garlena, Rebecca A.; Russell, Daniel A.; Jacobs-Sera, Deborah; Hatfull, Graham F.

    2016-01-01

    Bacteriophages Phinally and Vivi2 were isolated from soil from Pittsburgh, Pennsylvania, USA, using host Gordonia terrae 3612. The Phinally and Vivi2 genomes are 59,265 bp and 59,337 bp, respectively, and share sequence similarity with each other and with GTE6. Fewer than 25% of the 87 to 89 putative genes have predictable functions. PMID:27540050

  19. Genome Sequences of Gordonia terrae Bacteriophages Phinally and Vivi2.

    PubMed

    Pope, Welkin H; Anderson, Kaitlyn C; Arora, Charu; Bortz, Michael E; Burnet, George; Conover, David H; D'Incau, Gina M; Ghobrial, Jonathan A; Jonas, Audrey L; Migdal, Emily J; Rote, Nicole L; German, Brian A; McDonnell, Jill E; Mezghani, Nadia; Schafer, Claire E; Thompson, Paige K; Ulbrich, Megan C; Yu, Victor J; Furbee, Emily C; Grubb, Sarah R; Warner, Marcie H; Montgomery, Matthew T; Garlena, Rebecca A; Russell, Daniel A; Jacobs-Sera, Deborah; Hatfull, Graham F

    2016-01-01

    Bacteriophages Phinally and Vivi2 were isolated from soil from Pittsburgh, Pennsylvania, USA, using host Gordonia terrae 3612. The Phinally and Vivi2 genomes are 59,265 bp and 59,337 bp, respectively, and share sequence similarity with each other and with GTE6. Fewer than 25% of the 87 to 89 putative genes have predictable functions. PMID:27540050

  20. Surface Albedo/BRDF Parameters (Terra/Aqua MODIS)

    DOE Data Explorer

    Trishchenko, Alexander

    2008-01-15

    Spatially and temporally complete surface spectral albedo/BRDF products over the ARM SGP area were generated using data from two Moderate Resolution Imaging Spectroradiometer (MODIS) sensors on Terra and Aqua satellites. A landcover-based fitting (LBF) algorithm is developed to derive the BRDF model parameters and albedo product (Luo et al., 2004a). The approach employs a landcover map and multi-day clearsky composites of directional surface reflectance. The landcover map is derived from the Landsat TM 30-meter data set (Trishchenko et al., 2004a), and the surface reflectances are from MODIS 500m-resolution 8-day composite products (MOD09/MYD09). The MOD09/MYD09 data are re-arranged into 10-day intervals for compatibility with other satellite products, such as those from the NOVA/AVHRR and SPOT/VGT sensors. The LBF method increases the success rate of the BRDF fitting process and enables more accurate monitoring of surface temporal changes during periods of rapid spring vegetation green-up and autumn leaf-fall, as well as changes due to agricultural practices and snowcover variations (Luo et al., 2004b, Trishchenko et al., 2004b). Albedo/BRDF products for MODIS on Terra and MODIS on Aqua, as well as for Terra/Aqua combined dataset, are generated at 500m spatial resolution and every 10-day since March 2000 (Terra) and July 2002 (Aqua and combined), respectively. The purpose for the latter product is to obtain a more comprehensive dataset that takes advantages of multi-sensor observations (Trishchenko et al., 2002). To fill data gaps due to cloud presence, various interpolation procedures are applied based on a multi-year observation database and referring to results from other locations with similar landcover property. Special seasonal smoothing procedure is also applied to further remove outliers and artifacts in data series.

  1. Terra MODIS Band 27 Electronic Crosstalk Effect and Its Removal

    NASA Technical Reports Server (NTRS)

    Sun, Junqiang; Xiong, Xiaoxiong; Madhavan, Sriharsha; Wenny, Brian

    2012-01-01

    The MODerate-resolution Imaging Spectroradiometer (MODIS) is one of the primary instruments in the NASA Earth Observing System (EOS). The first MODIS instrument was launched in December, 1999 on-board the Terra spacecraft. MODIS has 36 bands, covering a wavelength range from 0.4 micron to 14.4 micron. MODIS band 27 (6.72 micron) is a water vapor band, which is designed to be insensitive to Earth surface features. In recent Earth View (EV) images of Terra band 27, surface feature contamination is clearly seen and striping has become very pronounced. In this paper, it is shown that band 27 is impacted by electronic crosstalk from bands 28-30. An algorithm using a linear approximation is developed to correct the crosstalk effect. The crosstalk coefficients are derived from Terra MODIS lunar observations. They show that the crosstalk is strongly detector dependent and the crosstalk pattern has changed dramatically since launch. The crosstalk contributions are positive to the instrument response of band 27 early in the mission but became negative and much larger in magnitude at later stages of the mission for most detectors of the band. The algorithm is applied to both Black Body (BB) calibration and MODIS L1B products. With the crosstalk effect removed, the calibration coefficients of Terra MODIS band 27 derived from the BB show that the detector differences become smaller. With the algorithm applied to MODIS L1B products, the Earth surface features are significantly removed and the striping is substantially reduced in the images of the band. The approach developed in this report for removal of the electronic crosstalk effect can be applied to other MODIS bands if similar crosstalk behaviors occur.

  2. Ground-based vicarious radiometric calibration of Terra MODIS

    NASA Astrophysics Data System (ADS)

    Czapla-Myers, J.; Thome, K.

    2009-12-01

    Accurate radiometric calibration is required by Earth-observing systems to ensure that the derived data products are of the highest quality. Preflight calibration is used as a baseline to understand the system before it is launched on orbit, while post-launch calibration is used to understand changes that may have occurred due to the nature of launching an instrument into space. On-orbit radiometric calibration ensures that changes in the system, including any onboard calibration sources, can be monitored. The Remote Sensing Group at the University of Arizona has been directly involved in the ground-based vicarious calibration of both Terra and Aqua MODIS since their respective launches in 1999 and 2002. RSG personnel are present at a test site during sensor overpass, and surface reflectance and atmospheric attenuation measurements are used as inputs to a radiative transfer code to determine the top-of-atmosphere radiance for the sensor under test. In the case of Terra MODIS, a 1-km2 site at Railroad Valley, Nevada, is used as a test site. This work presents results obtained using the reflectance-based approach at RSG’s Railroad Valley test site. Results from 10 years of in situ data collection at Railroad Valley show a percent difference in the seven land spectral channels between RSG and Terra MODIS ranging from 1.6 % in channel 6 (1632 nm), to 5.1% in channel 4 (553 nm). The average percent difference for Terra MODIS’s seven land channels and RSG is 3.5%. The uncertainty is within the 3-5% predicted for ground-based vicarious calibration.

  3. Mineralogical, chemical, organic and microbial properties of subsurface soil cores from Mars Desert Research Station (Utah, USA): Phyllosilicate and sulfate analogues to Mars mission landing sites

    NASA Astrophysics Data System (ADS)

    Stoker, Carol R.; Clarke, Jonathan; Direito, Susana O. L.; Blake, David; Martin, Kevin R.; Zavaleta, Jhony; Foing, Bernard

    2011-07-01

    We collected and analysed soil cores from four geologic units surrounding Mars Desert Research Station (MDRS) Utah, USA, including Mancos Shale, Dakota Sandstone, Morrison formation (Brushy Basin member) and Summerville formation. The area is an important geochemical and morphological analogue to terrains on Mars. Soils were analysed for mineralogy by a Terra X-ray diffractometer (XRD), a field version of the CheMin instrument on the Mars Science Laboratory (MSL) mission (2012 landing). Soluble ion chemistry, total organic content and identity and distribution of microbial populations were also determined. The Terra data reveal that Mancos and Morrison soils are rich in phyllosilicates similar to those observed on Mars from orbital measurements (montmorillonite, nontronite and illite). Evaporite minerals observed include gypsum, thenardite, polyhalite and calcite. Soil chemical analysis shows sulfate the dominant anion in all soils and SO4>>CO3, as on Mars. The cation pattern Na>Ca>Mg is seen in all soils except for the Summerville where Ca>Na. In all soils, SO4 correlates with Na, suggesting sodium sulfates are the dominant phase. Oxidizable organics are low in all soils and range from a high of 0.7% in the Mancos samples to undetectable at a detection limit of 0.1% in the Morrison soils. Minerals rich in chromium and vanadium were identified in Morrison soils that result from diagenetic replacement of organic compounds. Depositional environment, geologic history and mineralogy all affect the ability to preserve and detect organic compounds. Subsurface biosphere populations were revealed to contain organisms from all three domains (Archaea, Bacteria and Eukarya) with cell density between 3.0×106 and 1.8×107 cells ml-1 at the deepest depth. These measurements are analogous to data that could be obtained on future robotic or human Mars missions and results are relevant to the MSL mission that will investigate phyllosilicates on Mars.

  4. MAVEN's Trajectory to Mars

    NASA Video Gallery

    This movie shows the cruise trajectory of NASA's Mars Atmosphere and Volatile Evolution (MAVEN) mission, which was launched on Nov. 18, 2013. It will arrive at Mars on Sept. 21, 2014, to explore th...

  5. The Mars Chamber

    NASA Video Gallery

    The Mars chamber is a box about the size of a refrigerator that re-creates the temperatures, pressures, and atmosphere of the Martian surface, essentially creating a Mars environment on Earth! Scie...

  6. Mission Applications of a HIAD for the Mars Southern Highlands

    NASA Technical Reports Server (NTRS)

    Winski, Richard; Bose, Dave; Komar, David R.; Samareh, Jamshid

    2013-01-01

    Recent discoveries of evidence of a flowing liquid in craters throughout the Mars Southern Highlands, like Terra Sirenum, have spurred interest in sending science missions to those locations; however, these locations are at elevations that are much higher (0 to +4 km MOLA) than any previous landing site (-1 to -4 km MOLA). New technologies may be needed to achieve a landing at these sites with significant payload mass to the surface. A promising technology is the hypersonic inflatable aerodynamic decelerator (HIAD); a number of designs have been advanced but the stacked torus has been recently successfully flight tested in the IRVE-2 and IRVE-3 projects through the NASA Langley Research Center. This paper will focus on a variety of mission applications of the stacked torus type attached HIAD to the Mars southern highlands.

  7. Status of Terra and Aqua MODIS Instrument Operation and Calibration

    NASA Astrophysics Data System (ADS)

    Xiong, X.; Wenny, B. N.; Sun, J.; Angal, A.; Salomonson, V. V.

    2013-12-01

    Terra and Aqua MODIS have successfully operated for more than 13 and 11 years since their respective launches in 1999 and 2002. Nearly 40 data products, developed for studies of the earth's land, ocean, and atmosphere, have been routinely generated from calibrated and geo-located MODIS observations and widely distributed to the science and user community. MODIS on-orbit calibration is performed by a set of on-board calibrators, which include a solar diffuser for the reflective solar bands calibration and a blackbody for the thermal emissive bands calibration. MODIS on-board calibrators are regularly operated to monitor on-orbit changes in sensor responses and key performance parameters, such as radiometric calibration coefficients. Since launch, extensive instrument calibration and characterization activities have been scheduled and executed by the MODIS Characterization Support Team (MCST). This presentation provides an overview of both Terra and Aqua MODIS instrument status, their on-orbit operation and calibration activities, and overall long-term performance. It reports calibration improvements (algorithms and look-up tables) made in the latest MODIS data collection (C6). Lessons learned from both Terra and Aqua MODIS and their applications to the S-NPP VIIRS on-orbit calibration are also discussed.

  8. Geologic map of the Lada Terra quadrangle (V-56), Venus

    USGS Publications Warehouse

    Kumar, P. Senthil; Head, James W.

    2013-01-01

    This publication provides a geological map of Lada Terra quadrangle (V–56), a portion of the southern hemisphere of Venus that extends from lat 50° S. to 70° S. and from long 0° E. to 60° E. V–56 is bordered by Kaiwan Fluctus (V–44) and Agnesi (V–45) quadrangles in the north and by Mylitta Fluctus (V–61), Fredegonde (V–57), and Hurston (V–62) quadrangles in the west, east, and south, respectively. The geological map of V–56 quadrangle reveals evidence for tectonic, volcanic, and impact processes in Lada Terra in the form of tesserae, regional extensional belts, coronae, and volcanic plains. In addition, the map also shows relative age relations such as overlapping or cross-cutting relations between the mapped geologic units. The geology observed within this quadrangle addresses (1) how coronae evolved in association with regional extensional belts and (2) how tesserae, regional plains, and impact craters, which are also significant geological units observed in Lada Terra quadrangle, were formed.

  9. Saltation transport on Mars.

    PubMed

    Parteli, Eric J R; Herrmann, Hans J

    2007-05-11

    We present the first calculation of saltation transport and dune formation on Mars and compare it to real dunes. We find that the rate at which grains are entrained into saltation on Mars is 1 order of magnitude higher than on Earth. With this fundamental novel ingredient, we reproduce the size and different shapes of Mars dunes, and give an estimate for the wind velocity on Mars. PMID:17677662

  10. Mars Researchers Rendezvous on Remote Arctic Island

    NASA Technical Reports Server (NTRS)

    2002-01-01

    ice.

    The data were captured on June 28, 2001, during the early part of the arctic summer, when sea ice becomes thinner and begins to move depending upon localized currents and winds. In winter the entire region is locked with several meters of nearly motionless sea ice, which acts as a thermodynamic barrier to the loss of heat from the comparatively warm ocean to the colder atmosphere. Summer melting of sea ice can be observed at the two large, dark regions of open water; one is present in the Jones Sound (near the top to the left of center), and another appears in the Wellington Channel (left-hand edge). A large crack caused by tidal heaving has broken the ice cover over the Parry Channel (lower right-hand corner). A substantial ice cap permanently occupies the easternmost third of the island (upper right). Surface features such as dendritic meltwater channels incised into the island's surface are apparent. The Haughton-Mars project site is located slightly to the left and above image center, in an area which appears with relatively little surface ice, near the island's inner 'elbow.'

    The images were acquired during Terra orbit 8132 and cover an area of about 334 kilometers x 229 kilometers. They utilize data from blocks 27 to 31 within World Reference System-2 path 42.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  11. Tectonic Evolution of Mars

    NASA Technical Reports Server (NTRS)

    Phillips, Roger J.

    1992-01-01

    The Final Technical Report on tectonic evolution of Mars is presented. Two papers and an abstract are included. Topics addressed include: scientific rationale and requirements for a global seismic network on Mars, permanent uplift in magmatic systems with application to the Tharsis Region of Mars, and the geophysical signal of the Martian global dichotomy.

  12. Rotorcraft as Mars Scouts

    NASA Technical Reports Server (NTRS)

    Young, L. A.; Aiken, E. W.; Gulick, V.; Mancinelli, R.; Briggs, G. A.; Rutkowski, Michael (Technical Monitor)

    2002-01-01

    A new approach for the robotic exploration of Mars is detailed in this paper: the use of small, ultralightweight, autonomous rotary-wing aerial platforms. Missions based on robotic rotorcraft could make excellent candidates for NASA Mars Scout program. The paper details the work to date and future planning required for the development of such 'Mars rotorcraft.'

  13. 1 Main Street, Mars

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Located outside StenniSphere, the visitor center at John C. Stennis Space Center, 1 Main Street Mars is a model of how a habitat on Mars might look. Complete with thermometers, scales and clocks set to Martian equivalents, this exhibit shows how very different life on Mars can be.

  14. Mars: The Viking Discoveries.

    ERIC Educational Resources Information Center

    French, Bevan M.

    This booklet describes the results of NASA's Viking spacecraft on Mars. It is intended to be useful for the teacher of basic courses in earth science, space science, astronomy, physics, or geology, but is also of interest to the well-informed layman. Topics include why we should study Mars, how the Viking spacecraft works, the winds of Mars, the…

  15. Mars: 2010 - 2020

    NASA Technical Reports Server (NTRS)

    Li, Fuk K.

    2006-01-01

    This slide presentation reviews the Mars Exploration program for the current decade and beyond. The potential items for procurements for the Mars Science Laboratory (MSL) are discussed, as well as future technology investments to enable to continued development of exploration of Mars by rovers and orbiters that are planned and envisioned for future missions.

  16. Lunar and Planetary Science XXXV: Mars: Hydrology, Drainage, and Valley Systems

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The titles in this section include: 1) Analysis of Orientation Dependence of Martian Gullies; 2) A Preliminary Relationship between the Depth of Martian Gullies and the Abundance of Hydrogen on Near-Surface Mars; 3) Water Indicators in Sirenum Terra and around the Argyre Impact Basin, Mars; 4) The Distribution of Gullies and Tounge-shaped Ridges and Their Role in the Degradation of Martian Craters; 5) A Critical Evaluation of Crater Lake Systems in Memnonia Quadrangle, Mars; 6) Impact-generated Hydrothermal Activity at Gusev Crater: Implications for the Spirit Mission; 7) Characterization of the Distributary Fan in Holden NE Crater using Stereo Analysis; 8) Computational Analysis of Drainage Basins on Mars: Appraising the Drainage Density; 9) Hypsometric Analyses of Martian Basins: A Comparison to Terrestrial, Lunar, and Venusian Hypsometry; 10) Morphologic Development of Harmakhis Vallis, Mars; 11) Mangala Valles, Mars: Investigations of the source of Flood Water and Early Stages of Flooding; 12) The Formation of Aromatum Chaos and the Water Discharge Rate at Ravi Vallis; 13) Inferring Hydraulics from Geomorphology for Athabasca Valles, Mars; 14) The Origin and Evolution of Dao Vallis: Formation and Modification of Martian Channels by Structural Collapse and Glaciation; 15) Snowmelt and the Formation of Valley Networks on Martian Volcanoes; 16) Extent of Floating Ice in an Ancient Echus Chasma/Kasei Valley System, Mars.

  17. Aerosols and water vapor dynamics over the Kingdom of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Farahat, Ashraf; El-Askary, Hesham; Al-Shaibani, Abdulaziz; Dogan, Umran

    2014-05-01

    The Kingdom of Saudi Arabia contains a vast desert area and the home of some of the largest deserts worldwide. This nature subjects the area to numerous dust storms. This is in addition to local emissions transported from industrial activities. The Arabian Peninsula dust storms have a major impact on air quality and affects dust cycle around the world. The nature of dust also affects air, ground traffics, and human health. Aerosols play a pivotal role in global climate change through their effects on the hydrological cycle and solar energy budget. Recently there have been some trials to study the nature of dust over the kingdom using satellite remote sensing and modeling to investigate the impact of aerosols of natural and anthropogenic origins from both local emissions and long-range transport on the air quality and atmospheric composition, yet a lot more needs to be done. In this study, data obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board of Terra and Aqua satellites are used to analyze aerosols properties over the thirteen provinces of the Kingdom of Saudi Arabia from April 2003 to January 2012. This analysis will help to characterize aerosol and cloud properties, and the seasonal hydrological factors to establish the relative contributions of aerosols derived from different regions to the different Saudi provinces and their impacts on local atmospheric composition and air quality. During this period, we have examined possible nature and anthropogenic/natural aerosols/dust sources. The analysis is based on important parameters including the aerosol optical depth (AOD), fine mode fraction (FMF), cloud properties including cloud top temperature (CTT), cloud top pressure (CTP) and the water vapor column. Correlation between water vapor and AOD was observed over three provinces which could be a result of pollution aerosols rather than dust and is, hence, acting as cloud condensation nuclei (CCN). Increasing anomalous aerosols pattern

  18. Tracking Arabia-India motion from Miocene to Present

    NASA Astrophysics Data System (ADS)

    Chamot-Rooke, N. R.; Fournier, M.

    2009-12-01

    Although small, the present-day Arabia-India motion has been captured by several global and regional geodetic surveys that consistently show dextral motion of a few mm/yr, either transpressive or transtensive (Fournier et al., 2008). This motion is accommodated along the Owen Fracture Zone, an active strike-slip boundary that runs for more than 700 km from the Somalia-India-Arabia triple junction in the south to the Dalrymple trough in the north. Two recent marine cruises conducted along this fault aboard the BHO Beautemps-Beaupré (AOC 2006 and OWEN 2009) using a high resolution multibeam sounder (Simrad EM120, 10 m vertical resolution) provided a complete map of the active fault and confirmed a present-day pure dextral motion. The surface breaks closely follow a small circle of the Arabia-India motion, with several pull-part basins at the junctions between the main segments of the fault. Geomorphologic offsets reach 10 km, suggesting that the mapped fault has been active with the same style for past several million years. When did this motion start? The difficulty in tracking the past Arabia-India motion is that there is no direct kinematic indicator available, since the boundary has been strike-slip and/or convergent during the Tertiary. Motion was most probably sinistral during the rapid northward travelling of India towards Eurasia in the early Tertiary, Arabia being rigidly attached to Africa until the opening of the Gulf of Aden. However, the nature and location of the Arabia-India boundary at that time remain speculative. Throughout the Miocene, the relative motion between India and Arabia has been indirectly recorded at the Sheba and Carslberg ridges, the former recording Arabia-Somalia motion (opening of the Gulf of Aden) and the latter India-Somalia motion (Indian Ocean opening). Both ridges have been studied with some details recently, using up to date magnetic lineations identification (Merkouriev and DeMets, 2006; Fournier et al., 2009). We combine

  19. Mars Drilling Status

    NASA Technical Reports Server (NTRS)

    Mandell, Humboldt, C., Jr.

    2002-01-01

    This slide presentation reviews the current status of work to explore Mars beneath the surface of planet. One of the objective of this work is to enable further exploration of Mars by humans. One of the requirements for this is to find water on Mars. The presences of water is critical for Human Exploration and a permanent presence on Mars. If water is present beneath the surface it is the best chance of finding life on Mars. The presentation includes a timeline showing the robotic missions, those that have already been on Mars, and planned missions, an explanation of why do we want to drill on Mars, and some of the challenges, Also include are reviews of a missions that would drill 200 and 4,000 to 6,000 meters into the Martian bedrock, and a overview description of the drill. There is a view of some places where we have hopes of finding water.

  20. Solar Power on Mars

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This chart illustrates the variation in available solar power for each of NASA's twin Mars Exploration Rovers over the course of approximately two Mars years. Two factors affect the amount of available power: the tilt of Mars' axis and the eccentricity of the Mars' orbit about the sun.

    The horizontal scale is the number of Martian days (sols) after the Jan. 4, 2004, (Universal Time) landing of Spirit at Mars' Gusev Crater. The vertical scale on the right indicates the amount of available solar power as a ratio of the amount available at the equator when Mars is closest to the sun (perihelion). The red line indicates power availability at Spirit's landing site (Gusev). The blue line indicates power availability at Opportunity's landing site (Meridiani).

    The vertical scale on the right applies to the dotted line, indicating the latitude north or south of Mars' equator where the noon sun is overhead at different times of the Martian year.

  1. Mars transportation system synthesis

    NASA Astrophysics Data System (ADS)

    Young, Archie C.; Mulqueen, John A.; Emrich, William J.

    Performance and requirements synthesized to support the manned Mars mission of the Space Exploration Initiative (SEI) are presented. Emphasis is placed on the Mars transportation system (MTS), which uses nuclear thermal rocket (NTR) propulsion technology associated with accomplishing the manned Mars mission. Data are also presented for a propulsion system options comparison of chemical/aerobrake and nuclear electric propulsion systems. Vehicle- and weight-scaling are used to determine the MTS mass, size, and performance range required for different Mars mission durations. The split sprint, opposition, and conjunction class mission modes are employed to determine the MTS requirements envelope. MTS sensitivity to Mars surface payload, crew size, Mars orbit payload, NTR engine thrust level, engine specific impulse, and NTR engine thrust-to-weight ratio are synthesized. A suggested NTR technology level to accomplish both cargo and piloted Mars missions is discussed.

  2. Isotopic composition of Riyadh rainfall, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Michelsen, Nils; Reshid, Mustefa; Siebert, Christian; Schulz, Stephan; Rausch, Randolf; Knöller, Kay; Weise, Stephan; Al-Saud, Mohammed; Schüth, Christoph

    2015-04-01

    Arid countries like Saudi Arabia often depend on fossil groundwater. Hence, thorough studies of the available resources are crucial. In the course of such investigations, analyses of δ18O and δD are frequently applied to constrain the provenance of the waters and to reconstruct the (paleo)climatic conditions during their recharge. Yet, to be able to evaluate the isotopic signature of the groundwater, one also has to know the isotopic composition of current precipitation. Although a few rain water analyses are available for Central Saudi Arabia in the literature - mostly in unpublished consultant reports - a Local Meteoric Water Line has never been established. To complement the available data, 28 rain events occurring in Riyadh between 2009 and 2013 were studied for their stable isotope composition. Samples were collected as integral samples, i.e., they represent the entire precipitation event. Moreover, one event was sampled several times, aiming at an evaluation of intra-storm variability. During selected storms, a grab sample was taken for 3H analysis. The event samples showed δ18O and δD values scattering between -6.5 and +9.5 and between -30 and +50 ‰ V-SMOW, respectively. In the course of the event that was sequentially sampled, a proceeding isotopic depletion was observed with respect to both isotopes. The relatively large ranges of δ-values for 18O and D of approximately 7 and 38 ‰ V-SMOW highlight the general need for integral sampling. The obtained grab samples are characterized by moderate 3H concentrations of a few Tritium Units. Further results will be presented and discussed in view of associated weather data (e.g. rain amount and temperature) and the probable moisture sources derived from back-trajectories, which were calculated using HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory Model; Draxler & Rolph, 2003). References Draxler, R.R. & Rolph, G.D. (2013): HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory

  3. The non-coding RNA TERRA is a natural ligand and direct inhibitor of human telomerase

    PubMed Central

    Redon, Sophie; Reichenbach, Patrick; Lingner, Joachim

    2010-01-01

    Telomeres, the physical ends of eukaryotes chromosomes are transcribed into telomeric repeat containing RNA (TERRA), a large non-coding RNA of unknown function, which forms an integral part of telomeric heterochromatin. TERRA molecules resemble in sequence the telomeric DNA substrate as they contain 5′-UUAGGG-3′ repeats near their 3′-end which are complementary to the template sequence of telomerase RNA. Here we demonstrate that endogenous TERRA is bound to human telomerase in cell extracts. Using in vitro reconstituted telomerase and synthetic TERRA molecules we demonstrate that the 5′-UUAGGG-3′ repeats of TERRA base pair with the RNA template of the telomerase RNA moiety (TR). In addition TERRA contacts the telomerase reverse transcriptase (TERT) protein subunit independently of hTR. In vitro studies further demonstrate that TERRA is not used as a telomerase substrate. Instead, TERRA acts as a potent competitive inhibitor for telomeric DNA in addition to exerting an uncompetitive mode of inhibition. Our data identify TERRA as a telomerase ligand and natural direct inhibitor of human telomerase. Telomerase regulation by the telomere substrate may be mediated via its transcription. PMID:20460456

  4. Gulf Cooperation Council: Arabia's model of integration

    SciTech Connect

    Etaibi, G.T.

    1984-01-01

    This study is an analysis of the foundations and emergence in 1981 of the Gulf Cooperation Council (GCC), which consists of six traditional Arab Gulf states (the United Arab Emirates, Bahrain, Saudi Arabia, Oman, Qatar, and Kuwait). It finds the GCC to be a unique case among twentieth-century integrative schemes. The study also identifies and analyzes relevant local, regional, and international forces. Among the local forces are traditional religio-political systems, economic dependence on a depletable resource, and the presence of a large number of foreign residents. On the regional level, this study takes into consideration such issues as the Arab League, Arab Nationalism, and the Islamic revolutionary movement in Iran. On the international level, the influence of the superpowers and the major industrialized nations on the emergence and future of the GCC Community are analyzed. Throughout the past decade there has been a growing scholarly interest in the Gulf region. In preparation for this study, the author relied heavily on the literature generated by this new research, as well as on documents and official publications, mostly in Arabic. A survey was conducted among a limited number of GCC graduate students during the summer of 1983. In addition, interviews with selected members of the GCC Secretariat-General and various member-state officials were conducted during a research trip in the region in the spring of 1984.

  5. Mars reconnaissance lander: Vehicle and mission design

    NASA Astrophysics Data System (ADS)

    Williams, H. R.; Bridges, J. C.; Ambrosi, R. M.; Perkinson, M.-C.; Reed, J.; Peacocke, L.; Bannister, N. P.; Howe, S. D.; O'Brien, R. C.; Klein, A. C.

    2011-10-01

    There is enormous potential for more mobile planetary surface science. This is especially true in the case of Mars because the ability to cross challenge terrain, access areas of higher elevation, visit diverse geological features and perform long traverses of up to 200 km supports the search for past water and life. Vehicles capable of a ballistic ‘hop’ have been proposed on several occasions, but those proposals using in-situ acquired propellants are the most promising for significant planetary exploration. This paper considers a mission concept termed Mars Reconnaissance Lander using such a vehicle. We describe an approach where planetary science requirements that cannot be met by a conventional rover are used to derive vehicle and mission requirements. The performance of the hopper vehicle was assessed by adding estimates of gravity losses and mission mass constraints to recently developed methods. A baseline vehicle with a scientific payload of 16.5 kg and conservatively estimated sub-system masses is predicted to achieve a flight range of 0.97 km. Using a simple consideration of system reliability, the required cumulative range of 200 km could be achieved with a probability of around 80%. Such a range is sufficient to explore geologically diverse terrains. We therefore plot an illustrative traverse in Hypanis Valles/Xanthe Terra, which encounters crater wall sections, periglacial terrain, aqueous sedimentary deposits and a traverse up an ancient fluvial channel. Such a diversity of sites could not be considered with a conventional rover. The Mars Reconnaissance Lander mission and vehicle presents some very significant engineering challenges, but would represent a valuable complement to rovers, static landers and orbital observations.

  6. 15 Years of Terra, 14 Years of Application Usage

    NASA Astrophysics Data System (ADS)

    Schmaltz, J. E.; Alarcon, C.; Boller, R. A.; Cechini, M. F.; Davies, D.; Fu, G.; Gunnoe, T.; Hall, J. R.; Huang, T.; Ilavajhala, S.; Jackson, M.; King, J.; McGann, M.; Murphy, K. J.; Roberts, J. T.; Thompson, C. K.; Ye, G.

    2014-12-01

    The instruments onboard the Terra spacecraft were designed for long-term Earth science research but not long after launch it became apparent that this data and imagery could be made available in near real-time for applications users. During the year 2000 fire season in the western United States, the US Forest Service approached NASA with a request to expedite MODIS fire detections. The Rapid Response system was created to generate fire detections as well as true color imagery in both swath and geo-referenced formats. This imagery was used by a wide variety of applications, such as NASA's AERONET program, the USDA Foreign Agricultural Service, Antarctic resupply shipping, flood mapping for relief agencies, Deepwater Horizon monitoring, volcanic ash monitoring, as well as print, televised, and Internet media. From 2004, the University of Maryland's Web Fire Mapper helped distribute fire detection information in a variety of formats. However, the applications community expressed the need for near-real time access to the underlying data. This requirement led to the development of the Land Atmosphere Near real-time Capability for EOS (Earth Observing System) (LANCE) in 2009. To achieve the latency requirements, many components of the EOS satellite operations, ground and science processing systems had to be made more efficient. In addition, products that require ancillary data were modified to use alternate inputs. Forty Terra MODIS data products are currently available from LANCE. LANCE also includes data from other instruments including AIRS, AMSR-E, MLS, and OMI. To help near-real time users navigate this large data offering, a new imagery service was begun in 2011 - Global Imagery Browse Services (GIBS). This service provides very responsive viewing using the Web Map Tile Service protocol. These programs will continue to support and expand the use of Terra data for near-real time applications well into the future.

  7. Electronic crosstalk in Terra MODIS thermal emissive bands

    NASA Astrophysics Data System (ADS)

    Sun, Junqiang; Madhavan, Sriharsha; Xiong, Xiaoxiong; Wang, Menghua

    2015-09-01

    The MODerate-resolution Imaging Spectroradiometer (MODIS) is a legacy Earth remote sensing instrument in the National Aeronautics and Space Administration (NASA) Earth Observing System (EOS). The first MODIS instrument was launched in December 1999 on board the Terra spacecraft. MODIS has 36 bands, among which bands 20-25 and bands 27-36 are thermal emissive bands covering a wavelength range from 3.7μm to 14.2μm. It has been found that there are severe contaminations in Terra bands 27-30 (6.7 μm - 9.73 μm) due to crosstalk of signals among themselves. The crosstalk effect induces strong striping artifacts in the Earth View (EV) images and causes large long-term drifts in the EV brightness temperature (BT) in these bands. An algorithm using a linear approximation derived from on-orbit lunar observations has been developed to correct the crosstalk effect for them. It was demonstrated that the crosstalk correction can substantially reduce the striping noise in the EV images and significantly remove the long-term drifts in the EV BT in the Long Wave InfraRed (LWIR) water vapor channels (bands 27-28). In this paper, the crosstalk correction algorithm previously developed is applied to correct the crosstalk effect in the remaining LWIR bands 29 and 30. The crosstalk correction successfully reduces the striping artifact in the EV images and removes long-term drifts in the EV BT in bands 29-30 as was done similarly for bands 27-28. The crosstalk correction algorithm can thus substantially improve both the image quality and the radiometric accuracy of the Level 1B (L1B) products of the LWIR PV bands, bands 27-30. From this study it is also understood that other Terra MODIS thermal emissive bands are contaminated by the crosstalk effect and that the algorithm can be applied to these bands for crosstalk correction.

  8. The need for national medical licensing examination in Saudi Arabia

    PubMed Central

    Bajammal, Sohail; Zaini, Rania; Abuznadah, Wesam; Al-Rukban, Mohammad; Aly, Syed Moyn; Boker, Abdulaziz; Al-Zalabani, Abdulmohsen; Al-Omran, Mohammad; Al-Habib, Amro; Al-Sheikh, Mona; Al-Sultan, Mohammad; Fida, Nadia; Alzahrani, Khalid; Hamad, Bashir; Al Shehri, Mohammad; Abdulrahman, Khalid Bin; Al-Damegh, Saleh; Al-Nozha, Mansour M; Donnon, Tyrone

    2008-01-01

    Background Medical education in Saudi Arabia is facing multiple challenges, including the rapid increase in the number of medical schools over a short period of time, the influx of foreign medical graduates to work in Saudi Arabia, the award of scholarships to hundreds of students to study medicine in various countries, and the absence of published national guidelines for minimal acceptable competencies of a medical graduate. Discussion We are arguing for the need for a Saudi national medical licensing examination that consists of two parts: Part I (Written) which tests the basic science and clinical knowledge and Part II (Objective Structured Clinical Examination) which tests the clinical skills and attitudes. We propose this examination to be mandated as a licensure requirement for practicing medicine in Saudi Arabia. Conclusion The driving and hindering forces as well as the strengths and weaknesses of implementing the licensing examination are discussed in details in this debate. PMID:19032779

  9. New Faults Map Study for Central Part of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Bin Fayez, A.

    2006-05-01

    The Institute of Astronomy and Geophysics Research at King Abdulaziz City for Science and Technology installed nine earthquake portable stations in central part of Saudi Arabia around Riyadh city to record micro- seismicty that is caused by local faults. Riyadh city and central part of Saudi Arabia are located in the Arabian Plate, which is known as a relatively stable platform. However, we have been able to determine some events that was caused by local faults. Most of these events are not felt. We are using digital recorders (RefTek 72A) for data acquisition and SAISAN software for analyses. The velocity model that I have used in this study is IASPEI model. Currently I am developing a map that shows some micro-earthquake events for that region. In addition, it includes some regional events. The objective of this study is to define the active faults in central part of Saudi Arabia.

  10. Essays on oil and business cycles in Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Aba Alkhail, Bandar A.

    This dissertation consists of three chapters. Chapter one presents a theoretical model using a dynamic stochastic general equilibrium (DSGE) approach to investigate the role of world oil prices in explaining the business cycle in Saudi Arabia. This model incorporates both productivity and oil revenue shocks. The results indicate that productivity shocks are relatively more important to business cycles than oil shocks. However, this model has some unfavorable features that are associated with both investment and labor hours. The second chapter presents a modified theoretical model using DSGE approach to examine the role of world oil prices versus productivity shocks in explaining the business cycles in Saudi Arabia. To overcome the unfavorable features of the baseline model, the alternative model adds friction to the model by incorporating investment portfolio adjustment cost. Thus, the alternative model produces similar dynamics to that of the baseline model but the unfavorable characteristics are eliminated. Also, this chapter conducts sensitivity analysis. The objective of the third chapter is to empirically investigate how real world oil price and productivity shocks affect output, consumption, investment, labor hours, and trade balance/output ratio for Saudi Arabia. This chapter complements the theoretical model of the previous chapters. In addition, this study builds a foundation for future studies in examining the impact of real world oil price shocks on the economies of key trade partners of Saudi Arabia. The results of the third chapter show that productivity shocks matter more for macroeconomic fluctuations than oil shocks for the Saudis' primary trade partners. Therefore, fears of oil importing countries appear to be overstated. As a whole, this research is important for the following reasons. First, the empirical model is consistent with the predictions of our theoretical model in that productivity is a driving force of business cycles in Saudi Arabia

  11. Cars on Mars

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2002-01-01

    Mars is one of the most fascinating planets in the solar system, featuring an atmosphere, water, and enormous volcanoes and canyons. The Mars Pathfinder, Global Surveyor, and Odyssey missions mark the first wave of the Planet Earth's coming invasion of the red planet, changing our views of the past and future of the planet and the possibilities of life. Scientist and science-fiction writer Geoffrey A. Landis will present experiences on the Pathfinder mission, the challenges of using solar power on the surface of Mars, and present future missions to Mars such as the upcoming Mars Twin Rovers, which will launch two highly-capable vehicles in 2003 to explore the surface of Mars.

  12. Sample Analysis At Mars

    NASA Technical Reports Server (NTRS)

    Brinckerhoff, W. B.; Mahaffy, P. R.; Cabane, M.; Atreya, S. K.; Coll, P.; Cornish, T. J.; Harpold, D. N.; Israel, G.; Niemann, H. B.; Owen, T.

    2003-01-01

    The next landed missions to Mars, such as the planned Mars Science Laboratory and ExoMars, will require sample analysis capabilities refined well beyond what has been flown to date. A key science objective driving this requirement is the determination of the carbon inventory of Mars, and particularly the detection of organic compounds. While the gas chromatograph mass spectrometers (GCMS) on the Viking landers did not detect any indigenous organics in near surface fines, it is possible that these measurements were not representative of Mars on the whole. That is, those compounds to which the GC/MS was sensitive would likely not have survived the strong oxidative decomposition in the regolith at the landing sites in question. The near surface fines could very well contain a significant quantity of refractory compounds that would not have been volatilized in the sample ovens on Viking. It is also possible that volatile organics exist on Mars in sedimentary, subsurface, or polar niches.

  13. Sample Analysis at Mars

    NASA Technical Reports Server (NTRS)

    Brinckerhoff, W. B.; Mahaffy, P. R.; Cabane, M.; Atreya, S. K.; Coll, P.; Cornish, T. J.; Harpold, D. N.; Israel, G.; Niemann, H. B.; Owen, T.

    2003-01-01

    The next landed missions to Mars, such as the planned Mars Science Laboratory and ExoMars, will require sample analysis capabilities refined well beyond what has been flown to date. A key science objective driving this requirement is the determination of the carbon inventory of Mars, and particularly the detection of organic compounds. While the gas chromatograph mass spectrometers (GC/MS) on the Viking landers did not detect any indigenous organics in near surface fines, it is possible that these measurements were not representative of Mars on the whole. That is, those compounds to which the GC/MS was sensitive would likely not have survived the strong oxidative decomposition in the regolith at the landing sites in question. The near surface fines could very well contain a significant quantity of refractory compounds that would not have been volatilized in the sample ovens on Viking. It is also possible that volatile organics exist on Mars in sedimentary, subsurface, or polar niches.

  14. Mars Surface Habitability Options

    NASA Technical Reports Server (NTRS)

    Howe, A. Scott; Simon, Matthew; Smitherman, David; Howard, Robert; Toups, Larry; Hoffman, Stephen J.

    2015-01-01

    This paper reports on current habitability concepts for an Evolvable Mars Campaign (EMC) prepared by the NASA Human Spaceflight Architecture Team (HAT). For many years NASA has investigated alternative human Mars missions, examining different mission objectives, trajectories, vehicles, and technologies; the combinations of which have been referred to as reference missions or architectures. At the highest levels, decisions regarding the timing and objectives for a human mission to Mars continue to evolve while at the lowest levels, applicable technologies continue to advance. This results in an on-going need for assessments of alternative system designs such as the habitat, a significant element in any human Mars mission scenario, to provide meaningful design sensitivity characterizations to assist decision-makers regarding timing, objectives, and technologies. As a subset of the Evolvable Mars Campaign activities, the habitability team builds upon results from past studies and recommends options for Mars surface habitability compatible with updated technologies.

  15. Mars Solar Power

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Kerslake, Thomas W.; Jenkins, Phillip P.; Scheiman, David A.

    2004-01-01

    NASA missions to Mars, both robotic and human, rely on solar arrays for the primary power system. Mars presents a number of challenges for solar power system operation, including a dusty atmosphere which modifies the spectrum and intensity of the incident solar illumination as a function of time of day, degradation of the array performance by dust deposition, and low temperature operation. The environmental challenges to Mars solar array operation will be discussed and test results of solar cell technology operating under Mars conditions will be presented, along with modeling of solar cell performance under Mars conditions. The design implications for advanced solar arrays for future Mars missions is discussed, and an example case, a Martian polar rover, are analyzed.

  16. Mars elevation distribution

    NASA Technical Reports Server (NTRS)

    Wu, Sherman S. C.; Howington-Kraus, Annie E.; Ablin, Karyn K.

    1991-01-01

    A Digital Terrain Model (DTM) of Mars was derived with both Mercator and Sinusoidal Equal-Area projections from the global topographic map of Mars (scale 1:15 million, contour interval 1 km). Elevations on the map are referred to Mars' topographic datum that is defined by the gravity field at a 6.1-millibar pressure surface with respect to the center of mass of Mars. The DTM has a resolution at the equator of 1/59.226 degrees (exactly 1 km) per pixel. By using the DTM, the volumetric distribution of Mars topography above and below the datum has previously been calculated. Three types of elevation distributions of Mars' topography were calculated from the same DTM: (1) the frequency distribution of elevations at the pixel resolution; (2) average elevations in increments of 6 degrees in both longitude and latitude; and (3) average elevations in 36 separate blocks, each covering 30 degrees of latitude and 60 degrees of longitude.

  17. Quick trips to Mars

    NASA Technical Reports Server (NTRS)

    Hornung, R.

    1991-01-01

    The design of a Mars Mission Vehicle that would have to be launched by two very heavy lift launch vehicles is described along with plans for a mission to Mars. The vehicle has three nuclear engine for rocket vehicle application (NERVA) boosters with a fourth in the center that acts as a dual mode system. The fourth generates electrical power while in route, but it also helps lift the vehicle out of earth orbit. A Mars Ascent Vehicle (MAV), a Mars transfer vehicle stage, and a Mars Excursion Vehicle (MEV) are located on the front end of this vehicle. Other aspects of this research including aerobraking, heat shielding, nuclear thermal rocket engines, a mars mission summary, closed Brayton cycle with and without regeneration, liquid hydrogen propellant storage, etc. are addressed.

  18. CRISM's Global Mapping of Mars, Part 2

    NASA Technical Reports Server (NTRS)

    2007-01-01

    750, one of 209 tiles just delivered to the PDS. It shows a part of the planet called Tyrrhena Terra in the ancient, heavily cratered highlands. The colored strips are CRISM multispectral survey data acquired over several months, in which each pixel has a calibrated 72-color spectrum of Mars. The three wavelengths shown are 2.53, 1.50, and 1.08 micrometers in the red, green, and blue image planes respectively. At these wavelengths, rocky areas appear brown, dusty areas appear tan, and regions with hazy atmosphere appear bluish. Note that there is a large difference in brightness between strips, because there is no correction for the lighting conditions at the time of each observation. The gray areas between the strips are from an earlier mosaic of the planet taken by the Thermal Emission Imaging System (THEMIS) instrument on Mars Odyssey, and are included only for context. Ultimately the multispectral survey will cover nearly all of this area.

    CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter and the Mars Science Laboratory for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter.

  19. CRISM's Global Mapping of Mars, Part 1

    NASA Technical Reports Server (NTRS)

    2007-01-01

    750, one of 209 tiles just delivered to the PDS. It shows a part of the planet called Tyrrhena Terra in the ancient, heavily cratered highlands. The colored strips are CRISM multispectral survey data acquired over several months, in which each pixel has a calibrated 72-color spectrum of Mars. The three wavelengths shown are 2.53, 1.50, and 1.08 micrometers in the red, green, and blue image planes respectively. At these wavelengths, rocky areas appear brown, dusty areas appear tan, and regions with hazy atmosphere appear bluish. Note that there is a large difference in brightness between strips, because there is no correction for the lighting conditions at the time of each observation. The gray areas between the strips are from an earlier mosaic of the planet taken by the Thermal Emission Imaging System (THEMIS) instrument on Mars Odyssey, and are included only for context. Ultimately the multispectral survey will cover nearly all of this area.

    CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter and the Mars Science Laboratory for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter.

  20. Mars: The Viking discoveries

    NASA Technical Reports Server (NTRS)

    French, B. M.

    1977-01-01

    An overview of the Viking Mars probe is presented. The Viking spacecraft is described and a brief history of the earlier observations and exploration of Mars is provided. A number of the Viking photographs of the Martian surface are presented and a discussion of the experiments Viking performed including a confirmation of the general theory of relativity are reported. Martian surface chemistry is discussed and experiments to study the weather on Mars are reported.

  1. Mars at Opposition

    ERIC Educational Resources Information Center

    Riddle, Bob

    2010-01-01

    On January 29, Mars will reach opposition, a point along its orbit around the Sun where Mars will be directly opposite from the Sun in a two-planet and Sun line-up with the Earth in between. At this opposition, the Earth and Mars will be separated by nearly 100 million km. An opposition is similar to a full Moon in that the planet at opposition…

  2. Magnetic Strips Preserve Record of Ancient Mars

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This image is a map of Martian magnetic fields in the southern highlands near the Terra Cimmeria and Terra Sirenum regions, centered around 180 degrees longitude from the equator to the pole. It is where magnetic stripes possibly resulting from crustal movement are most prominent. The bands are oriented approximately east - west and are about 100 miles wide and 600 miles long, although the longest band stretches more than 1200 miles. The false blue and red colors represent invisible magnetic fields in the Martian crust that point in opposite directions. The magnetic fields appear to be organized in bands, with adjacent bands pointing in opposite directions, giving these stripes a striking similarity to patterns seen in the Earth's crust at the mid-oceanic ridges.

    NASA's Mars Global Surveyor has discovered surprising new evidence of past movement of the Martian crust, suggesting that ancient Mars was a more dynamic, Earth-like planet than it is today.

    Scientists using the spacecraft's magnetometer have found banded patterns of magnetic fields on the Martian surface. The adjacent magnetic bands point in opposite directions, giving these invisible stripes a striking similarity to patterns seen in the crust of Earth's sea floors.

    [figure removed for brevity, see original site] (P50330,MRPS94769)

    Above: An artist's concept comparing the present day magnetic fields on Earth and Mars. Earth's magnetic field is generated by an active dynamo - a hot core of molten metal. The magnetic field surrounds Earth and is considered global (left). The various Martian magnetic fields (right) do not encompass the entire planet and are local. The Martian dynamo is extinct, and its magnetic fields are 'fossil' remnants of its ancient, global magnetic field. I

    On the Earth, the sea floor spreads apart slowly at mid-oceanic ridges as new crust flows up from Earth's hot interior. Meanwhile, the direction of Earth's magnetic field reverses occasionally, resulting in

  3. Options for Mars exploration

    NASA Technical Reports Server (NTRS)

    Pritchard, E. B.; Harrison, E. F.; Moore, J. W.

    1974-01-01

    The many possible post-Viking 1975 Mars mission options are explored. These include small atmospheric probe/landers (adaptations of the Venus Pioneer to Mars), repeat Vikings with and without science changes, long-life orbiters to provide coverage of both hemispheres for a full Martian year, small rovers deployed from the Viking lander with ranges of up to 1 km from it, large autonomous rovers, Mars sample-return missions and, finally, missions to the satellites of Mars, including sample return. The examination includes energy requirements and time frames.

  4. Mars Stratigraphy Mission

    NASA Technical Reports Server (NTRS)

    Budney, C. J.; Miller, S. L.; Cutts, J. A.

    2000-01-01

    The Mars Stratigraphy Mission lands a rover on the surface of Mars which descends down a cliff in Valles Marineris to study the stratigraphy. The rover carries a unique complement of instruments to analyze and age-date materials encountered during descent past 2 km of strata. The science objective for the Mars Stratigraphy Mission is to identify the geologic history of the layered deposits in the Valles Marineris region of Mars. This includes constraining the time interval for formation of these deposits by measuring the ages of various layers and determining the origin of the deposits (volcanic or sedimentary) by measuring their composition and imaging their morphology.

  5. Alluvial Fans on Mars

    NASA Technical Reports Server (NTRS)

    Kraal, E. R.; Moore, J. M.; Howard, A. D.; Asphaug, E. A.

    2005-01-01

    Moore and Howard [1] reported the discovery of large alluvial fans in craters on Mars. Their initial survey from 0-30 S found that these fans clustered in three distinct regions and occurred at around the +1 km MOLA defined Mars datum. However, due to incomplete image coverage, Moore and Howard [1]could not conduct a comprehensive survey. They also recognized, though did not quantitatively address, gravity scaling issues. Here, we briefly discuss the identification of alluvial fans on Mars, then consider the general equations governing the deposition of alluvial fans and hypothesize a method for learning about grain size in alluvial fans on Mars.

  6. Digital cartography of Mars

    NASA Technical Reports Server (NTRS)

    Batson, R. M.

    1987-01-01

    A medium-resolution Digital Image Model (DIM) of Mars is being compiled. A DIM is a mosaic of radiometrically corrected, photometrically modelled spacecraft images displaying accurate reflectance properties at uniform resolution, and geometrically tied to the best available control. The Mars medium-resolution DIM contains approximately 4700 Viking Orbiter image frames that were used to compile the recently completed 1:2,000,000-scale controlled photomosaic series of Mars. This DIM provides a planimetric control base to which all other Mars maps will be registered. A similar control base of topographic elevations (Digital Terrain Model, or DTM) is also being compiled. These products are scheduled for completion in 1989.

  7. A Mars base

    NASA Technical Reports Server (NTRS)

    Soule, Veronique

    1989-01-01

    This study was initiated to provide an approach to the development of a permanently manned Mars base. The objectives for a permanently manned Mars base are numerous. Primarily, human presence on Mars will allow utilization of new resources for the improvement of the quality of life on Earth, allowing for new discoveries in technologies, the solar system, and human physiology. Such a mission would also encourage interaction between different countries, increasing international cooperation and leading to a stronger unification of mankind. Surface studies of Mars, scientific experiments in the multiple fields, the research for new minerals, and natural resource production are more immediate goals of the Mars mission. Finally, in the future, colonization of Mars will ensure man's perpetual presence in the universe. Specific objectives of this study were: (1) to design a Mars habitat that minimizes the mass delivered to the Mars surface, provides long-stay capability for the base crew, and accommodates future expansion and modification; (2) to develop a scenario of the construction of a permanently manned Mars base; and (3) to incorporate new and envisioned technologies.

  8. Seasonal Surface Spectral Emissivity Derived from Terra MODIS Data

    NASA Technical Reports Server (NTRS)

    Sun-Mack, Sunny; Chen, Yan; Minnis, Patrick; Young, DavidF.; Smith, William J., Jr.

    2004-01-01

    The CERES (Clouds and the Earth's Radiant Energy System) Project is measuring broadband shortwave and longwave radiances and deriving cloud properties form various images to produce a combined global radiation and cloud property data set. In this paper, simultaneous data from Terra MODIS (Moderate Resolution Imaging Spectroradiometer) taken at 3.7, 8.5, 11.0, and 12.0 m are used to derive the skin temperature and the surface emissivities at the same wavelengths. The methodology uses separate measurements of clear sky temperature in each channel determined by scene classification during the daytime and at night. The relationships between the various channels at night are used during the day when solar reflectance affects the 3.7- m radiances. A set of simultaneous equations is then solved to derive the emissivities. Global monthly emissivity maps are derived from Terra MODIS data while numerical weather analyses provide soundings for correcting the observed radiances for atmospheric absorption. These maps are used by CERES and other cloud retrieval algorithms.

  9. Flood routing of the Maja outflow across Xanthe Terra

    NASA Technical Reports Server (NTRS)

    Dehon, R. A.

    1991-01-01

    The object is to trace a single flood crest through the Maja outflow system and to evaluate the effects of topography on ponding and multiple channel routing. Maja Valles provides a good model because it has a single source and a well defined channel system. The 1500 km long Maja Valles originates in Juventae Chasma. The outflow system stretches 1100 km northward along the Lunae Planum/Xanthe Terra boundary, then eastward across the Xanthe Terra highlands. It descends to Chryse Planitia where it extends northeastward toward the middle of the basin. It is concluded that flood routing through multiple channels and retardation in local impoundments are responsible for breakup of the initial flood crest and the formation of multiple flood crests. Recombined flow near the mouths of these canyons results in an extended flow regime and multiple flood surges. As a result of ponding along the flood course, depositional sites are localized and renewed erosion downstream (from ponded sites) results in sediment source areas not greatly removed from depositional sites.

  10. A fully automated TerraSAR-X based flood service

    NASA Astrophysics Data System (ADS)

    Martinis, Sandro; Kersten, Jens; Twele, André

    2015-06-01

    In this paper, a fully automated processing chain for near real-time flood detection using high resolution TerraSAR-X Synthetic Aperture Radar (SAR) data is presented. The processing chain including SAR data pre-processing, computation and adaption of global auxiliary data, unsupervised initialization of the classification as well as post-classification refinement by using a fuzzy logic-based approach is automatically triggered after satellite data delivery. The dissemination of flood maps resulting from this service is performed through an online service which can be activated on-demand for emergency response purposes (i.e., when a flood situation evolves). The classification methodology is based on previous work of the authors but was substantially refined and extended for robustness and transferability to guarantee high classification accuracy under different environmental conditions and sensor configurations. With respect to accuracy and computational effort, experiments performed on a data set of 175 different TerraSAR-X scenes acquired during flooding all over the world with different sensor configurations confirm the robustness and effectiveness of the proposed flood mapping service. These promising results have been further confirmed by means of an in-depth validation performed for three study sites in Germany, Thailand, and Albania/Montenegro.

  11. Status of Terra MODIS Operation, Calibration, and Performance

    NASA Technical Reports Server (NTRS)

    Xiong, X.; Wenny, B.; Wu, A.; Angal, A.; Geng, X.; Chen, H.; Dodd, J.; Link, D.; Madhavan, S.; Chen, N.; Li, Y.; Iacangelo, S.; Barnes, W.; Salomonson, V.

    2014-01-01

    Since launch in December 1999, Terra MODIS has successfully operated for nearly 15 years, making continuous observations. Data products derived from MODIS observations have significantly contributed to a wide range of studies of key geophysical parameters of the earth's eco-system of land, ocean, and atmosphere, and their changes over time. The quality of MODIS data products relies on the dedicated effort to monitor and sustain instrument health and operation, to calibrate and update sensor parameters and properties, and to improve calibration algorithms. MODIS observations are made in 36 spectral bands, covering wavelengths from visible to long-wave infrared. The reflective solar bands (1-19 and 26) are primarily calibrated by a solar diffuser (SD) panel and regularly scheduled lunar observations. The thermal emissive bands (20-25 and 27- 36) calibration is referenced to an on-board blackbody (BB) source. On-orbit changes in the sensor spectral and spatial characteristics are monitored by a spectroradiometric calibration assembly (SRCA). This paper provides an overview of Terra MODIS on-orbit operation and calibration activities and implementation strategies. It presents and summarizes sensor on-orbit performance using nearly 15 years of data from its telemetry, on-board calibrators, and lunar observations. Also discussed in this paper are changes in sensor characteristics, corrections applied to maintain MODIS level 1B (L1B) data quality, and efforts for future improvements.

  12. Retrieval algorithm development and product validation for TERRA/MOPITT

    NASA Astrophysics Data System (ADS)

    Deeter, M. N.; Martínez-Alonso, S.; Worden, H. M.; Emmons, L. K.; Dean, V.; Mao, D.; Edwards, D. P.; Gille, J. C.

    2014-10-01

    Satellite observations of tropospheric carbon monoxide (CO) are employed in diverse applications including air quality studies, chemical weather forecasting and the characterization of CO emissions through inverse modeling. The TERRA / MOPITT ('Measurements of Pollution in the Troposphere') instrument incorporates a set of gas correlation radiometers to observe CO simultaneously in both a thermal-infrared (TIR) band near 4.7 µm and a near-infrared (NIR) band near 2.3 μm. This multispectral capability is unique to MOPITT. The MOPITT retrieval algorithm for vertical profiles of CO has been refined almost continuously since TERRA was launched at the end of 1999. Retrieval algorithm enhancements are the result of ongoing analyses of instrument performance, improved radiative transfer modeling, and systematic comparisons with correlative data, including in-situ profiles measured from aircraft and products from other satellite instruments. In the following, we describe the methods used to routinely evaluate MOPITT CO profiles. As the satellite instrument with the longest record for CO, methods for assessing the long-term stability are becoming increasingly important.

  13. The crosstalk of telomere dysfunction and inflammation through cell-free TERRA containing exosomes.

    PubMed

    Wang, Zhuo; Lieberman, Paul M

    2016-08-01

    Telomeric repeats-containing RNA (TERRA) are telomere-derived non-coding RNAs that contribute to telomere function in protecting chromosome ends. We recently identified a cell-free form of TERRA (cfTERRA) enriched in extracellular exosomes. These cfTERRA-containing exosomes stimulate inflammatory cytokines when incubated with immune responsive cells. Here, we report that cfTERRA levels were increased in exosomes during telomere dysfunction induced by the expression of the dominant negative TRF2. The exosomes from these damaged cells also enriched with DNA damage marker γH2AX and fragmented telomere repeat DNA. Purified cfTERRA stimulated inflammatory cytokines, but the intact membrane-associated nucleoprotein complexes produced a more robust cytokine activation. Therefore, we propose cfTERRA-containing exosomes transport a telomere-associated molecular pattern (TAMP) and telomere-specific alarmin from dysfunctional telomeres to the extracellular environment to elicit an inflammatory response. Since cfTERRA can be readily detected in human serum it may provide a useful biomarker for the detection of telomere dysfunction in the early stage of cancers and aging-associated inflammatory disease. PMID:27351774

  14. Two MODIS Aerosol Products Over Ocean on the Terra and Aqua CERES SSF Datasets

    NASA Technical Reports Server (NTRS)

    Ignatov, Alexander; Minnis, Patrick; Loeb, Norman; Wielicki, Bruce; Miller, Walter; Sun-Mack, Sunny; Tanre, Didier; Remer, Lorraine; Laszlo, Istvan; Geier, Erika

    2004-01-01

    Over ocean, two aerosol products are reported on the Terra and Aqua CERES SSFs. Both are derived from MODIS, but using different sampling and aerosol algorithms. This study briefly summarizes these products, and compares using 2 weeks of global Terra data from 15-21 December 2000, and 1-7 June 2001.

  15. EPA SITE DEMONSTRATION OF THE TERRA VAC IN SITU VACUUM EXTRACTION PROCESS IN GROVELAND, MASSACHUSETTS

    EPA Science Inventory

    This paper presents an EPA evaluation of the patented Terra Vac, Inc.'s in situ vacuum extraction process that was field-demonstrated on a trichloroethylene (TCE) contaminated soil in Groveland, MA, under the EPA Superfund Innovative Technology Evaluation (SITE) program. he Terra...

  16. Terra-Kleen Response Group, Inc. Solvent Extraction Technology Rapid Commercialization Initiative Report

    EPA Science Inventory

    Terra-Kleen Response Group Inc. (Terra-Kleen), has commercialized a solvent extraction technology that uses a proprietary extraction solvent to transfer organic constituents from soil to a liquid phase in a batch process at ambient temperatures. The proprietary solvent has a rel...

  17. The Najd Fault System of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Stüwe, Kurt; Kadi, Khalid; Abu-Alam, Tamer; Hassan, Mahmoud

    2014-05-01

    The Najd Fault System of the Arabian-Nubian Shield is considered to be the largest Proterozoic Shear zone system on Earth. The shear zone was active during the late stages of the Pan African evolution and is known to be responsible for the exhumation of fragments of juvenile Proterozoic continental crust that form a series of basement domes across the shield areas of Egypt and Saudi Arabia. A three year research project funded by the Austrian Science Fund (FWF) and supported by the Saudi Geological Survey (SGS) has focused on structural mapping, petrology and geochronology of the shear zone system in order to constrain age and mechanisms of exhumation of the domes - with focus on the Saudi Arabian side of the Red Sea. We recognise important differences in comparison with the basement domes in the Eastern desert of Egypt. In particular, high grade metamorphic rocks are not exclusively confined to basement domes surrounded by shear zones, but also occur within shear zones themselves. Moreover, we recognise both exhumation in extensional and in transpressive regimes to be responsible for exhumation of high grade metamorphic rocks in different parts of the shield. We suggest that these apparent structural differences between different sub-regions of the shield largely reflect different timing of activity of various branches of the Najd Fault System. In order to tackle the ill-resolved timing of the Najd Fault System, zircon geochronology is performed on intrusive rocks with different cross cutting relationships to the shear zone. We are able to constrain an age between 580 Ma and 605 Ma for one of the major branches of the shear zone, namely the Ajjaj shear zone. In our contribution we present a strain map for the shield as well as early geochronological data for selected shear zone branches.

  18. Early primate evolution in Afro-Arabia.

    PubMed

    Seiffert, Erik R

    2012-11-01

    The peculiar mammalian fauna that inhabited Afro-Arabia during the Paleogene first came to the attention of the scientific community in the early part of the twentieth century, when Andrews1 and Schlosser2 published their landmark descriptions of fossil mammals from the Fayum Depression in northern Egypt. Their studies revealed a highly endemic assemblage of land mammals that included the first known Paleogene records of hyraxes, proboscideans, and anthropoid primates, but which lacked ancestors of many iconic mammalian lineages that are found in Africa today, such as rhinos, zebras, bovids, giraffes, and cats. Over the course of the last century, the Afro-Arabian Paleogene has yielded fossil remains of several other endemic mammalian lineages,3 as well as a diversity of prosimian primates,4 but we are only just beginning to understand how the continent's faunal composition came to be, through ancient processes such as the movement of tectonic plates, changes in climate and sea level, and early phylogenetic splits among the major groups of placental mammals. These processes, in turn, made possible chance dispersal events that were critical in determining the competitive landscape--and, indeed, the survival--of our earliest anthropoid ancestors. Newly discovered fossils indicate that the persistence and later diversification of Anthropoidea was not an inevitable result of the clade's competitive isolation or adaptive superiority, as has often been assumed, but rather was as much due to the combined influences of serendipitous geographic conditions, global cooling, and competition with a group of distantly related extinct strepsirrhines with anthropoid-like adaptations known as adapiforms. Many of the important details of this story would not be known, and could never have been predicted, without the fossil evidence that has recently been unearthed by field paleontologists. PMID:23280921

  19. Exobiology and Future Mars Missions

    NASA Technical Reports Server (NTRS)

    Mckay, Christopher P. (Editor); Davis, Wanda, L. (Editor)

    1989-01-01

    Scientific questions associated with exobiology on Mars were considered and how these questions should be addressed on future Mars missions was determined. The mission that provided a focus for discussions was the Mars Rover/Sample Return Mission.

  20. Magnetic Strips Preserve Record of Ancient Mars

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This image is a map of Martian magnetic fields in the southern highlands near the Terra Cimmeria and Terra Sirenum regions, centered around 180 degrees longitude from the equator to the pole. It is where magnetic stripes possibly resulting from crustal movement are most prominent. The bands are oriented approximately east - west and are about 100 miles wide and 600 miles long, although the longest band stretches more than 1200 miles. The false blue and red colors represent invisible magnetic fields in the Martian crust that point in opposite directions. The magnetic fields appear to be organized in bands, with adjacent bands pointing in opposite directions, giving these stripes a striking similarity to patterns seen in the Earth's crust at the mid-oceanic ridges.

    NASA's Mars Global Surveyor has discovered surprising new evidence of past movement of the Martian crust, suggesting that ancient Mars was a more dynamic, Earth-like planet than it is today.

    Scientists using the spacecraft's magnetometer have found banded patterns of magnetic fields on the Martian surface. The adjacent magnetic bands point in opposite directions, giving these invisible stripes a striking similarity to patterns seen in the crust of Earth's sea floors.

    [figure removed for brevity, see original site] (P50330,MRPS94769)

    Above: An artist's concept comparing the present day magnetic fields on Earth and Mars. Earth's magnetic field is generated by an active dynamo - a hot core of molten metal. The magnetic field surrounds Earth and is considered global (left). The various Martian magnetic fields (right) do not encompass the entire planet and are local. The Martian dynamo is extinct, and its magnetic fields are 'fossil' remnants of its ancient, global magnetic field. I

    On the Earth, the sea floor spreads apart slowly at mid-oceanic ridges as new crust flows up from Earth's hot interior. Meanwhile, the direction of Earth's magnetic field reverses occasionally, resulting in

  1. Review of NASA's Planned Mars Program

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Contents include the following: Executive Summary; Introduction; Scientific Goals for the Exploration of Mars; Overview of Mars Surveyor and Others Mars Missions; Key Issues for NASA's Mars Exploration Program; and Assessment of the Scientific Potential of NASA's Mars Exploration Program.

  2. Ages of plains volcanism on Mars

    NASA Astrophysics Data System (ADS)

    Hauber, Ernst; Jagert, Felix; Broz, Petr

    2010-05-01

    on models of the endogenic evolution of Mars. We determined the ages of 60 shield volcanoes and lava flows in Tharsis. The ages within a given shield cluster are similar among themselves, with a smaller spread in the age distribution in the younger clusters. Most clusters have ages <100 Ma. Shields in Tempe Terra are older, with ages of a few hundred million years. The oldest cluster is located in Syria Planum (ca. 1.3 Ga - 2.9 Ga). Our results indicate that Late Amazonian volcanism is more widespread in Tharsis than previously recognized. Based on our results it appears possible that Mars is volcanologically not dead yet. Ongoing work investigates the volumes of erupted products and implications for the outgassing history and atmospheric evolution of Mars. [1] Greeley R. (1982) JGR 87, 2705-2712. [2] Plescia J. (1981) Icarus, 45, 586-601. [3] Hodges C.A. and Moore H.J. (1994) Atlas of volcanic features on Mars: USGS Prof. Paper 1534, 194 p. [4] Hauber E. et al. (2009) J. Volcanol. Geotherm. Res. 185, 69-95. [5] Wilson L. et al. (2009) J. Volcanol. Geotherm. Res. 185, 28-46. [6] Vaucher, J. et al. (2009) Icarus 204, 418-442. [7] Baratoux D. et al. (2009) J. Volcanol. Geotherm. Res. 185, 47-68. [8] Bleacher J.E. et al. (2009) J. Volcanol. Geotherm. Res. 185, 96-102. [9] Ivanov B.A. (2001) Space Sci. Rev. 96, 87-104. [10] Hartmann W.H. and Neukum G. (2001) Space Sci. Rev. 96, 165-194 [11] Kneissl T. et al. (2010) LPS XVI, submitted. [12] Michael, G.G. and Neukum G. (2010) Earth Planet. Sci. Lett., in press. . [13] Malin M.C. et al. (2007) JGR 112, E05S04, doi: 10.1029/2006JE002808.

  3. University Teacher Educators' Research Engagement: Perspectives from Saudi Arabia

    ERIC Educational Resources Information Center

    Borg, Simon; Alshumaimeri, Yousif

    2012-01-01

    This paper examines university teacher educators' engagement with and in educational research. Survey results collected from eighty-two teacher educators at a leading university in Saudi Arabia pointed to modest levels of research activity and also suggested that these individuals held largely technical views of what research is. Their assessments…

  4. Lactase persistence variants in Arabia and in the African Arabs.

    PubMed

    Priehodová, Edita; Abdelsawy, Abdelhay; Heyer, Evelyne; Cerný, Viktor

    2014-01-01

    Lactase persistence (LP), the state enabling the digestion of milk sugar in adulthood, occurs only in some human populations. The convergent and independent origin of this physiological ability in Europe and Africa is linked with animal domestication that either had started in both places independently or had spread from the Near East by acculturation. However, it has recently been shown that at least in its southern parts, the population of Arabia not only has a different LP-associated mutation profile than the rest of Africa and Europe but also had experienced an independent demographic expansion occurring before the Neolithic around the Pleistocene-Holocene boundary. In Arabia, LP is associated with mutation -13,915*G and not, as in Europe, with -13,910*T or, as in Africa, with -13,907*G and -14,010*C. We show here that, in Arabia, -13,915*G frequency conforms to a partial clinal pattern and that this specific mutation has likely been spread from Arabia to Africa only recently from the sixth century AD onward by nomadic Arabs (Bedouins) looking for new pastures. Arabic populations in Africa that still maintain a nomadic way of life also have more -13,915*G variants and fewer sub-Saharan L-type mitochondrial DNA haplogroups; this observation matches archaeological and historical records suggesting that the migration of Arabic pastoralists was accompanied by gradual sedentarization that allowed for admixture with the local African population. PMID:25401983

  5. Geomatics Education in Saudi Arabia: Status, Challenges and Prospects

    ERIC Educational Resources Information Center

    Aina, Yusuf Adedoyin

    2009-01-01

    Geospatial technology has been identified as one of the three most important emerging fields along with nanotechnology and biotechnology. The application of the technology is expected to grow and become more diversified in the coming years. In Saudi Arabia, the utilization of geotechnology is growing but still limited compared to the Western…

  6. Human Resource Development in Saudi Arabia: An International Affair.

    ERIC Educational Resources Information Center

    Campbell, Clifton P.

    Saudi Arabia has a modern nationwide school system that embraces institutions from kindergarten through the university level and encompasses special, adult, industrial, and commercial education. Education is not compulsory, and coeducation does not exist. Secondary vocational industrial schools have been established for young men who have…

  7. Coesite from Wabar crater, near Al Hadida, Arabia

    USGS Publications Warehouse

    Chao, E.C.T.; Fahey, J.J.; Littler, J.

    1961-01-01

    The third natural occurrence of coesite, the high pressure polymorph of silica, is found at the Wabar meteorite crater, Arabia. The Wabar crater is about 300 feet in diameter and about 40 feet deep. It is the smallest of three craters where coesite has been found.

  8. Investigating Difficulties of Learning Computer Programming in Saudi Arabia

    ERIC Educational Resources Information Center

    Alakeel, Ali M.

    2015-01-01

    Learning computer programming is one of the main requirements of many educational study plans in higher education. Research has shown that many students face difficulties acquiring reasonable programming skills during their first year of college. In Saudi Arabia, there are twenty-three state-owned universities scattered around the country that…

  9. Measuring the Climate of Training in Saudi Arabia.

    ERIC Educational Resources Information Center

    Spicer, Richard G.

    1981-01-01

    One practitioner's experience in setting up on-the-job training in Saudi Arabia is described, including training materials, cultural environment, and the Saudi work ethic. In a related article, off-duty life for Americans is discussed, including dress for women and men, cultural aspects, and entertainment. (CT)

  10. Islam's Point of View on Women's Education in Saudi Arabia.

    ERIC Educational Resources Information Center

    Al-Hariri, Rafeda

    1987-01-01

    Shows links between Islamic doctrine and girls' education in Saudi Arabia providing examples of ways in which the Islamic attitude towards women and social life is applied to educational policy. Summarizes educational opportunities available for girls and women and notes milestones in the 26-year history of girls' education. (JHZ)

  11. Libraries of Two Women's Colleges in Saudi Arabia.

    ERIC Educational Resources Information Center

    King, Elizabeth J.

    1987-01-01

    Describes the current status of higher education for women in Saudi Arabia and discusses the special problems of access to library materials encountered by women in this society, focusing on the collections, services, and administration of two women's colleges' libraries. A proposed national educational development plan is briefly described. (CLB)

  12. Developing a Career Resource for College Students in Saudi Arabia.

    ERIC Educational Resources Information Center

    Shatkin, Laurence; Atiyeh, Naim

    With the development of Career Oasis, King Fahd University of Petroleum and Minerals (KFUPM ) has pioneered the use of computer-based career guidance in Saudi Arabia. KFUPM contracted with Verbal Media, LLC, an American consulting company, to create a resource that would be available in both Arabic and English, in both online and paper-and-pencil…

  13. Pharmacy Curriculum and Health Care Needs in Saudi Arabia.

    ERIC Educational Resources Information Center

    Al-Sowaygh, Ibrahim A.; And Others

    1981-01-01

    Based on recognized health care needs, a curriculum revision was undertaken at the College of Pharmacy at Saudi Arabia's University of Riyadh. The revised curriculum included a unified basic health sciences core program for Medicine, Dentistry, Pharmacy, and Allied Medical Sciences. (Author/MLW)

  14. Middle East Respiratory Syndrome Coronavirus in Bats, Saudi Arabia

    PubMed Central

    Memish, Ziad A.; Mishra, Nischay; Olival, Kevin J.; Fagbo, Shamsudeen F.; Kapoor, Vishal; Epstein, Jonathan H.; AlHakeem, Rafat; Durosinloun, Abdulkareem; Al Asmari, Mushabab; Islam, Ariful; Kapoor, Amit; Briese, Thomas; Daszak, Peter; Al Rabeeah, Abdullah A.

    2013-01-01

    The source of human infection with Middle East respiratory syndrome coronavirus remains unknown. Molecular investigation indicated that bats in Saudi Arabia are infected with several alphacoronaviruses and betacoronaviruses. Virus from 1 bat showed 100% nucleotide identity to virus from the human index case-patient. Bats might play a role in human infection. PMID:24206838

  15. Individualized medicine enabled by genomics in Saudi Arabia

    PubMed Central

    2015-01-01

    The biomedical research sector in Saudi Arabia has recently received special attention from the government, which is currently supporting research aimed at improving the understanding and treatment of common diseases afflicting Saudi Arabian society. To build capacity for research and training, a number of centres of excellence were established in different areas of the country. Among these, is the Centre of Excellence in Genomic Medicine Research (CEGMR) at King Abdulaziz University, Jeddah, with its internationally ranked and highly productive team performing translational research in the area of individualized medicine. Here, we present a panorama of the recent trends in different areas of biomedical research in Saudi Arabia drawing from our vision of where genomics will have maximal impact in the Kingdom of Saudi Arabia. We describe advances in a number of research areas including; congenital malformations, infertility, consanguinity and pre-implantation genetic diagnosis, cancer and genomic classifications in Saudi Arabia, epigenetic explanations of idiopathic disease, and pharmacogenomics and personalized medicine. We conclude that CEGMR will continue to play a pivotal role in advances in the field of genomics and research in this area is facing a number of challenges including generating high quality control data from Saudi population and policies for using these data need to comply with the international set up. PMID:25951871

  16. Education and the Satellite: Possibilities for Saudi Arabia?

    ERIC Educational Resources Information Center

    Al-Sharhan, Jamal

    2000-01-01

    Discussion of developments in satellite communications and educational applications focuses on the possibilities of adapting satellite technology for instruction in developing countries. Topics include satellite use in Australia and the United States; and recommendations for the adoption of satellite technology in Saudi Arabia. (Author/LRW)

  17. Pre-Vocational Preparation in the Kingdom of Saudi Arabia.

    ERIC Educational Resources Information Center

    Campbell, Clifton P.

    In the Kingdom of Saudi Arabia, with few exceptions, occupational specialization programs for male students first become available at the secondary level (grades 10-12). Education is not compulsory, and substantial numbers drop out at all levels. Adolescents who leave school at the primary (elementary) or intermediate (grades 7-9) level must wait…

  18. 75 FR 21598 - Energy and Infrastructure Mission to Saudi Arabia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Energy and Infrastructure Mission to Saudi Arabia AGENCY: International Trade Administration, Department of Commerce. ACTION: Notice. Mission Description The United States Department of Commerce, International...

  19. 75 FR 54300 - Energy and Infrastructure Mission to Saudi Arabia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-07

    ... mission will include appointments, briefings and a networking reception in Riyadh and Jeddah, Saudi Arabia... will reach $173 by 2014, as personal computer (PC) penetration rises to more than 30%. The number of... networking reception. U.S. participants will be counseled before and after the mission by the...

  20. Foreign Language Planning in Saudi Arabia: Beyond English

    ERIC Educational Resources Information Center

    Payne, Mark; Almansour, Maram

    2014-01-01

    This paper presents findings from an exploratory study of foreign language planning in Saudi Arabia. In terms of official policy, the sole foreign language taught in Saudi public schools is English. Therefore, researching foreign languages there is often limited to researching the area of English as a Foreign Language. However, evidence shows that…

  1. The Teacher of English: Pedagogic Relevance in Saudi Arabia

    ERIC Educational Resources Information Center

    Khan, Intakhab Alam

    2011-01-01

    The present paper attempts to explore the characteristics of an effective teacher of English. Some related factors such as qualification, attributes, roles, and professional ethics have also been dealt with. In Saudi Arabia, the teacher of English plays the most important role in the process of teaching/learning. There are so many factors such as…

  2. Exploring Pedagogical Leadership in Early Years Education in Saudi Arabia

    ERIC Educational Resources Information Center

    Alameen, Lubna; Male, Trevor; Palaiologou, Ioanna

    2015-01-01

    The empirical research for this paper was undertaken with leaders of early years setting in the Kingdom of Saudi Arabia (KSA). The investigation sought to establish to what extent it was possible to behave in line with the concept of pedagogical leadership in the twenty-first century in an Arab Muslim monarchy, dominated by Islam, where directive…

  3. Aetiology of Neonatal Septicaemia in Qatif, Saudi Arabia.

    ERIC Educational Resources Information Center

    Elbashier, Ali M.; And Others

    1994-01-01

    Of the 1,797 babies admitted to a hospital in Saudi Arabia over a 3-year period, 8% were documented as having NNS. Identified several gram-positive bacteria, several gram-negative bacteria, and candida albicans as etiological agents in the cases of NNS. Determined the antibiotic susceptibility of the bacteria. (BC)

  4. Novel Gentic Variations Contributing to Asthma Susceptability in Saudi Arabia

    ClinicalTrials.gov

    2014-04-13

    Collection of Clinical Data That Will be Used in This Study and Will Form a Data Bank for Asthma in Saudi Arabia; Identify Known and NOVEL Genetic Risk Factors Contributing to Asthma Susceptibility; Study the Mechanistic Roles of the Genetic Variants Within Major Asthma Susceptibility Genes

  5. Medical Colleges in Saudi Arabia: Can We Predict Graduate Numbers?

    ERIC Educational Resources Information Center

    Althubaiti, Alaa; Alkhazim, Mohammad

    2014-01-01

    The shortage of Physicians is a major problem in many countries. Medical colleges are often encouraged to increase the graduate numbers. In the Kingdom of Saudi Arabia, Saudi physicians form only 37.89% of the physician manpower. The remainder of the physicians are expatriates. It was recently estimated that the Kingdom would need 29,128…

  6. Guidelines for Prospective EFL Teachers in Saudi Arabia.

    ERIC Educational Resources Information Center

    Joy, Constance Boerner

    Orientation materials for prospective teachers of English as a foreign language (EFL) in Saudi Arabia and other Middle Eastern countries contains information about factors affecting EFL teaching in the classroom. Topics discussed include religion, family, politics, education, English-Arabic language differences, teaching approaches, and the…

  7. Meteorological impact of realistic Terra Nova Bay polynyas.

    NASA Astrophysics Data System (ADS)

    Morelli, Sandra

    2010-05-01

    The energy exchange between the ocean and the atmosphere in the Antarctic marginal sea ice zone is influenced by the extent of sea-ice cover. In areas of open water, a direct contact is established and intense energy exchanges occur, due to the large difference of temperature between the water and the air above it. This implies that the polynyas are areas where the ocean exchanges energy with the atmosphere and as a result they have an effect on the polar meteorology/climate. The work presented here concerns real polynya events in the region of Terra Nova Bay (TNB), Antarctica, where a recurring coastal polynya occurs nearby the Italian Antarctic Base. The aim is the study of the impact of polynyas on the atmosphere by three-dimensional numerical simulations. The ETA model (Mesinger et al., 2006) was used and ECMWF and NCEP data provided the initial and boundary conditions. The model had already been successfully used in the Antarctic area (Casini and Morelli, 2007) A polynya of realistic size (as observed by satellite image) was included in the initial conditions for the simulations and a study of the air circulation during the events is found in Morelli et al. (2007), Morelli and Casini (2008), Morelli et al. (2009). The Eta Model reproduced the evolution of upper and mod-level conditions in good agreement with AVHRR observations (Morelli, 2008, Morelli and Parmiggiani, 2009). Also, the simulated 10 m wind was well correlated with the observed extension of the polynya. In order to isolate the effect of the presence of the open water area on the structure of the atmospheric boundary layer and on the atmospheric circulation, further simulations were performed without the presence of the polynya, i.e. with its extent covered with sea ice. The numerical simulations show that the polynyas act to increase the speed of the air above them and generate strong heat fluxes that warm the air. The effects are found over and downwind the sea ice free area. Results from the Eta

  8. Mars exploration planning

    NASA Technical Reports Server (NTRS)

    Eppler, Dean B.; Buoni, Corinne; Niehoff, John

    1993-01-01

    Mars exploration planning is discussed which is based on three scientific objectives: to understand Mars' geologic and geophysical evolution; to understand the present state and past evolution of Martian climate, and to determine the state of present biological activity and past life. The plan assumes a 25-year planning horizon, from 1995-2020, and includes both broad-scale and local exploration capabilities.

  9. Viking Mars encounter

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Various phases of planetary operations related to the Viking mission to Mars are described. Topics discussed include: approach phase, Mars orbit insertion, prelanding orbital activities, separation, descent and landing, surface operations, surface sampling and operations starting, orbiter science and radio science, Viking 2, Deep Space Network and data handling.

  10. Landing on Mars

    NASA Technical Reports Server (NTRS)

    Manning, Robert M.; Adler, Mark

    2005-01-01

    here have been five fully successful robotic landings on Mars. The systems used to deliver these robots to the surface have shown large design diversity and continue to evolve. How will future Mars landing systems evolve to eventually deliver precious human cargo? We do not yet know the answers, but current trends tell us an interesting and daunting tale.

  11. Plasma engineering for MARS

    SciTech Connect

    Carlson, G.A.; Baldwin, D.E.; Barr, W.L.

    1983-03-24

    The two-year Mirror Advanced Reactor Study (MARS) has resulted in the conceptual design of a commercial, electricity-producing fusion reactor based on tandem mirror confinement. The physics basis for the MARS reactor was developed through work in two highly coupled areas of plasma engineering: magnetics and plasma performance.

  12. Volatiles on Mars

    NASA Technical Reports Server (NTRS)

    Jakosky, Bruce M.

    1988-01-01

    The long-term evolution of both the atmosphere and the surface of Mars can be understood by examining the history of volatiles in the Mars atmosphere, their non-atmospheric reservoirs, and the processes of exchange between the two. Clearly, the present state of both the surface and the atmosphere can only be seen, so that any inferences about the evolution of the climate system are just that, inferences. The processes which control the atmosphere and surface on a seasonal basis, however, are the same processes which can act on longer timescales; only the specific solar and atmospheric forcing will differ. Once the ability of each process to affect the seasonal behavior is understood, the long-timescale forcing may be applied to the various processes in order to clearly identify the ability of the processes to act over the entire history of Mars. The areas of surface-atmospheric interaction of Mars are addressed in the ongoing research. The climate system on Mars is controlled by processes involving the exchange between the surface and atmosphere, so it is important to understand the current behavior of those processes. This is especially so in light of the current interest in understanding Mars; the upcoming Mars Observer mission, and the potential for a future sample-return or human-exploration mission will focus emphasis on this area of Mars science.

  13. Moessbauer on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken at Meridiani Planum, Mars, by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's Moessbauer spectrometer (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  14. Is Mars Red Hot?

    NASA Video Gallery

    What would it feel like if you could stand on Mars – toasty warm, or downright chilly? Find out more about the temperature on Mars in this 60-second video from NASA’s Jet Propulsion Laboratory.

  15. Mars transfer vehicle studies

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon

    1993-01-01

    Earth-to-Mars distances vary from 60 to 400 million kilometers over a 14-year cycle. This complicates Mars mission design as a function of calendar time. Stay times at Mars are also strongly driven by opportunities for a return flight path which are within the limits of delta-V associated with practical space vehicles. The biggest difference between Mars and lunar transfer missions is mission time, which grows from a few days for the moon, to as much as a few hundred days for Mars missions. As a result, modules for similarly sized crews must be much larger for Mars missions that for transfer to lunar orbit. Technology challenges for one Mars mission scenario analyzed by Boeing include aerobrakes, propulsion, and life support systems. Mission performance is very sensitive to aerobrake weight fraction and, as a result, there is an incentive to use high performance materials such as advanced composites and thermal protection systems. Lander aerobrake would be used twice (for both planetary capture and descent to the Mars surface), and it would need to survive temperatures up to 3500 degrees.

  16. Mars Exploratory Vehicles.

    ERIC Educational Resources Information Center

    Canizo, Thea L.; And Others

    1997-01-01

    Presents an activity in which students learn about the characteristics of the planet Mars. Challenges students to design and build a model of a robotic vehicle that can travel on the surface of Mars and accomplish an assigned task that will provide information useful for future manned trips to the planet. Outlines mission task cards and progress…

  17. Mars transfer vehicle studies

    NASA Astrophysics Data System (ADS)

    Woodcock, Gordon

    1993-02-01

    Earth-to-Mars distances vary from 60 to 400 million kilometers over a 14-year cycle. This complicates Mars mission design as a function of calendar time. Stay times at Mars are also strongly driven by opportunities for a return flight path which are within the limits of delta-V associated with practical space vehicles. The biggest difference between Mars and lunar transfer missions is mission time, which grows from a few days for the moon, to as much as a few hundred days for Mars missions. As a result, modules for similarly sized crews must be much larger for Mars missions that for transfer to lunar orbit. Technology challenges for one Mars mission scenario analyzed by Boeing include aerobrakes, propulsion, and life support systems. Mission performance is very sensitive to aerobrake weight fraction and, as a result, there is an incentive to use high performance materials such as advanced composites and thermal protection systems. Lander aerobrake would be used twice (for both planetary capture and descent to the Mars surface), and it would need to survive temperatures up to 3500 degrees.

  18. Microscope on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  19. The Mars Millennium Project.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    The countdown to a new century provides a unique opportunity to engage America's youth in charting a course for the future. The Mars Millennium Project challenges students across the nation to design a community yet to be imagined for the planet Mars. This interdisciplinary learning project aims to encourage K-12 students in classrooms and youth…

  20. Rat on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken on Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's rock abrasion tool, also known as 'rat' (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  1. Mars Underground News.

    NASA Astrophysics Data System (ADS)

    Edgett, K.

    Contents: Ten years Underground. Rover roundup (International Conference on Mobile Planetary Robots and Rover Roundup, Santa Monica, CA (USA), 29 Jan - 4 Feb 1997). Reaching the Red. Schedule of missions to Mars (as of April 1, 1997). Mars on the Web.

  2. The channels of Mars

    NASA Technical Reports Server (NTRS)

    Baker, Victor R.

    1988-01-01

    The geomorphology of Mars is discussed, focusing on the Martian channels. The great flood channels of Mars, the processes of channel erosion, and dendritic channel networks, are examined. The topography of the Channeled Scabland region of the northwestern U.S. is described and compared to the Martian channels. The importance of water in the evolution of the channel systems is considered.

  3. On the Stability of Liquid Water on Present Day Mars

    NASA Technical Reports Server (NTRS)

    Haberle, Robert M.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The mean annual surface pressure and temperature on present day Mars do not allow for the long term stability of liquid water on the surface. However, theoretical arguments have been advanced that suggest liquid water could form in transient events even though it would not be in equilibrium with the environment. Using a Mars General Circulation Model, we calculate where and for how long the surface pressure and surface temperature meet the minimum requirements for this metastability of liquid water. These requirements are that the pressure and temperature must be above the triple point of water, but below its boiling point. We find that there are five regions on Mars where these requirements are periodically satisfied: in the near equatorial regions of Amazonis, Arabia, and Elysium, and in the Hellas and Argyre impact basins. Whether liquid water ever forms in these regions depends on the availability of ice and heat, and on the evaporation rate. The latter is poorly understood for low pressure CO2 environments, but is likely to be so high that melting occurs rarely, if at all. However, in the relatively recent past, surface pressures may have been higher than they are today perhaps by as much as a factor of 2 or 3. Under these circumstances melting would have been easier to achieve. We plan to undertake laboratory experiments to better understand the potential for melting in low pressure environments.

  4. Mars Human Exploration Objectives

    NASA Technical Reports Server (NTRS)

    Briggs, Geoff

    1998-01-01

    This paper reviews the objectives and other considerations of Human exploration of Mars. The objectives of human exploration of Mars are: (1) to learn how Mars is similar to, and different from, Earth; (2) to explore possible life, past and present; (3) to discover what Mars is like now from the perspective of Geoscience and geologic history; and (4) how did Mars form and how did its formation differ from Earth. Considerations of human Martian exploration involve: (1) having a capable base laboratory; (2) having long range transportation; (3) having operational autonomy of the crew, and the requirement of the crew to possess a range of new cognitive processes along with easy communications with terrestrial colleagues; and finally (4) creating the human habitat along with human factors which involve more than just survivability.

  5. Ionosphere of Mars observed by Mars Express.

    NASA Astrophysics Data System (ADS)

    Dubinin, Eduard; Fraenz, Markus; Andrews, Dave; Morgan, Dave

    2016-04-01

    The Martian ionosphere is studied at different solar zenith angles using the local electron number densities and total electron content (TEC) derived from the observations by MARSIS onboard Mars Express. The data are complemented by the ASPERA-3 observations which provide us with the information about upward/downward velocity of the low-energy ions and electron precipitation. We consider the Mars Express observations at different solar cycle intervals. Different factors which influence the ionosphere dynamics are analyzed. The focus is made on a role of the crustal magnetic field on the Martian ionosphere and its influence on ion escape.

  6. Genetic stratigraphy of key demographic events in Arabia.

    PubMed

    Fernandes, Verónica; Triska, Petr; Pereira, Joana B; Alshamali, Farida; Rito, Teresa; Machado, Alison; Fajkošová, Zuzana; Cavadas, Bruno; Černý, Viktor; Soares, Pedro; Richards, Martin B; Pereira, Luísa

    2015-01-01

    At the crossroads between Africa and Eurasia, Arabia is necessarily a melting pot, its peoples enriched by successive gene flow over the generations. Estimating the timing and impact of these multiple migrations are important steps in reconstructing the key demographic events in the human history. However, current methods based on genome-wide information identify admixture events inefficiently, tending to estimate only the more recent ages, as here in the case of admixture events across the Red Sea (~8-37 generations for African input into Arabia, and 30-90 generations for "back-to-Africa" migrations). An mtDNA-based founder analysis, corroborated by detailed analysis of the whole-mtDNA genome, affords an alternative means by which to identify, date and quantify multiple migration events at greater time depths, across the full range of modern human history, albeit for the maternal line of descent only. In Arabia, this approach enables us to infer several major pulses of dispersal between the Near East and Arabia, most likely via the Gulf corridor. Although some relict lineages survive in Arabia from the time of the out-of-Africa dispersal, 60 ka, the major episodes in the peopling of the Peninsula took place from north to south in the Late Glacial and, to a lesser extent, the immediate post-glacial/Neolithic. Exchanges across the Red Sea were mainly due to the Arab slave trade and maritime dominance (from ~2.5 ka to very recent times), but had already begun by the early Holocene, fuelled by the establishment of maritime networks since ~8 ka. The main "back-to-Africa" migrations, again undetected by genome-wide dating analyses, occurred in the Late Glacial period for introductions into eastern Africa, whilst the Neolithic was more significant for migrations towards North Africa. PMID:25738654

  7. Genetic Stratigraphy of Key Demographic Events in Arabia

    PubMed Central

    Fernandes, Verónica; Triska, Petr; Pereira, Joana B.; Alshamali, Farida; Rito, Teresa; Machado, Alison; Fajkošová, Zuzana; Cavadas, Bruno; Černý, Viktor; Soares, Pedro

    2015-01-01

    At the crossroads between Africa and Eurasia, Arabia is necessarily a melting pot, its peoples enriched by successive gene flow over the generations. Estimating the timing and impact of these multiple migrations are important steps in reconstructing the key demographic events in the human history. However, current methods based on genome-wide information identify admixture events inefficiently, tending to estimate only the more recent ages, as here in the case of admixture events across the Red Sea (∼8–37 generations for African input into Arabia, and 30–90 generations for “back-to-Africa” migrations). An mtDNA-based founder analysis, corroborated by detailed analysis of the whole-mtDNA genome, affords an alternative means by which to identify, date and quantify multiple migration events at greater time depths, across the full range of modern human history, albeit for the maternal line of descent only. In Arabia, this approach enables us to infer several major pulses of dispersal between the Near East and Arabia, most likely via the Gulf corridor. Although some relict lineages survive in Arabia from the time of the out-of-Africa dispersal, 60 ka, the major episodes in the peopling of the Peninsula took place from north to south in the Late Glacial and, to a lesser extent, the immediate post-glacial/Neolithic. Exchanges across the Red Sea were mainly due to the Arab slave trade and maritime dominance (from ∼2.5 ka to very recent times), but had already begun by the early Holocene, fuelled by the establishment of maritime networks since ∼8 ka. The main “back-to-Africa” migrations, again undetected by genome-wide dating analyses, occurred in the Late Glacial period for introductions into eastern Africa, whilst the Neolithic was more significant for migrations towards North Africa. PMID:25738654

  8. ESA's Mars Program: European Plans for Mars Exploration

    NASA Technical Reports Server (NTRS)

    Forget, Francois

    2005-01-01

    A viewgraph presentation on the European Space Agency Mars Exploration Program is shown. The topics include: 1) History:Mars Exploration in Europe; 2) A few preliminary results from Mars Express; 3) A new instrument:Radar MARSIS; and 4) European Mars Exploration in the future?

  9. Summary of Aqua, Aura, and Terra High Interest Events

    NASA Technical Reports Server (NTRS)

    Newman, Lauri

    2015-01-01

    Single-obs tracking Sparsely tracked objects are an unfortunate reality of CARA operations Terra vs. 32081: new track with bad data was included in OD solution for secondary object and risk became high CARA and JSpOC discussed tracking and OSAs threw out the bad data. Event no longer presented high risk based on new OD Improvement: CARA now sends JSpOC a flag indicating when a single obs is included, so OSAs can evaluate if manual update to OD is required. Missing ASW OCMsAura vs. 87178, TCA: 317 at 08:04 UTC. Post-maneuver risk (conjunction was identified in OO results)CARA confirmed with JSpOC that ASW OCMs should have been received in addition to OO OCMsJSpOC corrected the manual error in their script that prevented the data from being delivered to CARAJSpOC QAd their other scripts to ensure this error did not exist in other places.

  10. TerraLuna: A CosmoQuest Adventure in Geology

    NASA Astrophysics Data System (ADS)

    Gay, Pamela; Bracey, Georgia; Gugliucci, Nicole

    The content of the session will focus on CosmoQuest’s TerraLuna unit, a comparative geology unit that uses authentic data to study the geology of the Moon and Earth. Inquiry activities will allow teachers to help their students compare crater formation and other surface features on the two bodies, comparing Moon features to similar structures on Earth. Links to the latest data from NASA’s Lunar Reconnaissance Orbiter will be introduced and hands- on activities will be featured as the basis for inquiry learning in elementary and middle level classrooms. Teachers will be introduced to citizen science projects that will enable their students to think like real scientists and engage in authentic scientific research, providing a useful service to the scientific community. Participation in the workshop introduces teachers to the CosmoQuest website, which includes a suite of citizen science activities. The site provides teachers with an online community dedicated to science inquiry and educational support.

  11. Regional Studies of Highland-Lowland Age Differences Across the Mars Crustal Dichotomy Boundary

    NASA Technical Reports Server (NTRS)

    Frey, H. V.; DeSoto, G. E.; Lazrus, R. M.

    2005-01-01

    Regional differences in crater retention ages (CRAs) across the Mars dichotomy boundary are compared to the global highland-lowland age difference previously determined from visible and buried impact basins based on MOLA-derived Quasi-Circular Depressions (QCDs). Here Western Arabia (WA) is compared with Ismenius Lacus (IL). We find the buried lowlands in the two regions have total CRAs essentially identical to the global average. Even more intriguing, the WA cratered terrain appears to have a CRA like that of the adjacent buried lowlands,

  12. 15 Years of Terra MODIS Instrument on-Orbit Performance

    NASA Astrophysics Data System (ADS)

    Xiong, X.; Salomonson, V.

    2014-12-01

    The first MODIS instrument, launched on-board the NASA EOS Terra spacecraft in December 1999, has successfully operated for nearly 15 years. MODIS observations have significantly contributed to the studies of many geophysical parameters of the earth's system and its changes over time. Dedicated effort made by the MODIS Characterization Support Team (MCST) to constantly monitor instrument operation, to calibrate changes in sensor response, to derive and update sensor calibration parameters, and to maintain and improve calibration algorithms has played an extremely important role to assure the quality of MODIS data products. MODIS was developed with overall improvements over its heritage sensors. Its observations are made in 36 spectral bands, covering wavelengths from visible to long-wave infrared. The reflective solar bands (1-19 and 26) are calibrated on-orbit by a solar diffuser (SD) panel and regularly scheduled lunar observations. The thermal emissive bands (20-25 and 27-36) calibration is referenced to an on-board blackbody (BB) source. On-orbit changes in the sensor spectral and spatial characteristics are tracked by a spectroradiometric calibration assembly (SRCA). This paper provides an overview of Terra MODIS on-orbit operation and calibration activities implemented from launch to present and the status of instrument health and functions. It demonstrates sensor on-orbit performance derived from its telemetry, on-board calibrators (OBC), and lunar observations. Also discussed in this paper are changes in sensor characteristics, corrections applied to maintain level 1B data quality, various challenging issues, and future improvements.

  13. TERRA Battery Thermal Control Anomaly - Simulation and Corrective Actions

    NASA Technical Reports Server (NTRS)

    Grob, Eric W.

    2010-01-01

    The TERRA spacecraft was launched in December 1999 from Vandenberg Air Force Base, becoming the flagship of NASA's Earth Observing System program to gather data on how the planet's processes create climate. Originally planned as a 5 year mission, it still provides valuable science data after nearly 10 years on orbit. On October 13th, 2009 at 16:23z following a routine inclination maneuver, TERRA experienced a battery cell failure and a simultaneous failure of several battery heater control circuits used to maintain cell temperatures and gradients within the battery. With several cells nearing the minimum survival temperature, preventing the electrolyte from freezing was the first priority. After several reset attempts and power cycling of the control electronics failed to reestablish control authority on the primary side of the controller, it was switched to the redundant side, but anomalous performance again prevented full heater control of the battery cells. As the investigation into the cause of the anomaly and corrective action continued, a battery thermal model was developed to be used in determining the control ability remaining and to simulate and assess corrective actions. Although no thermal model or detailed reference data of the battery was available, sufficient information was found to allow a simplified model to be constructed, correlated against pre-anomaly telemetry, and used to simulate the thermal behavior at several points after the anomaly. It was then used to simulate subsequent corrective actions to assess their impact on cell temperatures. This paper describes the rapid development of this thermal model, including correlation to flight data before and after the anomaly., along with a comparative assessment of the analysis results used to interpret the telemetry to determine the extent of damage to the thermal control hardware, with near-term corrective actions and long-term operations plan to overcome the anomaly.

  14. Intercomparison Calibration Study of Terra ASTER and MODIS

    NASA Astrophysics Data System (ADS)

    Yuan, K.; Thome, K. J.; McCorkel, J.

    2014-12-01

    Calibration and validation play an essential role during the acquisition and processing of satellite data for the Earth Observing System satellites in addition to being an integral part of maintaining scientific values of archived satellite data. The Advanced Spaceborne Thermal Emission and Reflection and Radiometer (ASTER) and Moderate Resolution Imaging Spectroradiometer (MODIS) are two of five sensors onboard the Terra platform - the Earth Observing System flagship. ASTER has a swath width of 60km with 8 bands in the visible and near infrared (VNIR) and thermal infrared (TIR) spectral range with a spatial resolution of 15m (bands 1-3) and 90m (bands 10-14), respectively while MODIS has a swath width of 2300km with 36 spectral bands from visible to infrared spectral range with a spatial resolution of 250m (bands 1-2), 500m (bands 3-7), and 1km (bands 8-36). ASTER is the 'zoom' lens and MODIS is the 'keystone' instrument for Terra; they provide quantitative measurements of various earth system variables to the scientific and to the broader community. The simultaneous view of the sensors simplifies the intercomparison between them and relies on the use of the Railroad Valley Playa test site to reduce uncertainties caused by spatial heterogeneity and spectral differences in the sensors. The fact that Railroad Valley Playa is a calibration test site for ASTER ensures that ASTER was tasked at a higher rate over this area providing more scenes for the intercomparison. The study compares ASTER L1B data for the three VNIR bands reprocessed with recent calibration updates and MODIS 02 Collection 6 data products for the similar bands. No correction for geometry angle is needed and coincident 3-km by 3-km regions are used to reduce the impact of spatial heterogeneity. A correction for spectral differences between the sensors is applied based on averages of ground measurements of the test site.

  15. Preliminary Operational Results of the TDRSS Onboard Navigation System (TONS) for the Terra Mission

    NASA Technical Reports Server (NTRS)

    Gramling, Cheryl; Lorah, John; Santoro, Ernest; Work, Kevin; Chambers, Robert; Bauer, Frank H. (Technical Monitor)

    2000-01-01

    The Earth Observing System Terra spacecraft was launched on December 18, 1999, to provide data for the characterization of the terrestrial and oceanic surfaces, clouds, radiation, aerosols, and radiative balance. The Tracking and Data Relay Satellite System (TDRSS) Onboard Navigation System (ONS) (TONS) flying on Terra provides the spacecraft with an operational real-time navigation solution. TONS is a passive system that makes judicious use of Terra's communication and computer subsystems. An objective of the ONS developed by NASA's Goddard Space Flight Center (GSFC) Guidance, Navigation and Control Center is to provide autonomous navigation with minimal power, weight, and volume impact on the user spacecraft. TONS relies on extracting tracking measurements onboard from a TDRSS forward-link communication signal and processing these measurements in an onboard extended Kalman filter to estimate Terra's current state. Terra is the first NASA low Earth orbiting mission to fly autonomous navigation which produces accurate results. The science orbital accuracy requirements for Terra are 150 meters (m) (3sigma) per axis with a goal of 5m (1 sigma) RSS which TONS is expected to meet. The TONS solutions are telemetered in real-time to the mission scientists along with their science data for immediate processing. Once set in the operational mode, TONS eliminates the need for ground orbit determination and allows for a smooth flow from the spacecraft telemetry to planning products for the mission team. This paper will present the preliminary results of the operational TONS solution available from Terra.

  16. The Morphologic Difference between Crater Slopes with and without Gullies on Mars.

    NASA Astrophysics Data System (ADS)

    Conway, S. J.; Mangold, N.; Balme, M. R.; Ansan, V.

    2012-04-01

    Gullies on Mars are km-scale landforms that resemble small fluvial features on Earth. Their discovery [1] challenged the paradigm that over the last ~2 Ga, Mars has been a dry, frozen desert. The gullies are found commonly in the mid-latitudes, have a pole-facing preference [e.g., 2] and are found many kinds of steep slope (valley wall, dunes, etc.). We have chosen to concentrate on gullies found on impact crater interior wall slopes, as this is the most common type [2]. The aim of our study is to determine whether the morphology of crater walls with and without gullies is different. We chose three study areas, two in the southern hemisphere (where gullies are most common), Terra Cimmeria and Noachis Terra and one in the northern hemisphere, Acidalia Planum. All study areas extend over at least 30° of latitude, from ~25° to 55° North or South. We mapped all craters using the catalog of [3] as a basis. We used HRSC elevation data at better than 100 m/pix to extract the slope and curvature of crater walls in the four cardinal directions. We mapped all the gullies on crater walls in the three areas with the aid of HiRISE, MOC, CTX and HRSC images, using polygons to delimit a slope section that contained gullies. Consistent with previous investigations we found gullies concentrated around 40° latitude, with a pole-facing preference. We also found that east-facing gullies were common in both hemispheres. Gullies were most common in Terra Cimmeria and uncommon in Noachis Terra. We found that for a given latitude band and orientation gullies tend to be found on craters with the steepest slopes and the highest curvature. The lack of gullies in Noachis Terra can be explained by the lack of steep, concave slopes in the mid-latitudes of this region. In Terra Cimmeria we found that almost all steep, concave crater slopes hosted gullies, whereas in Acidalia, in the north, only 10-20% of steep concave slopes had gullies. Crater slopes with gullies in the north are steeper

  17. Mars Exploration Rover surface mission flight thermal performance

    NASA Technical Reports Server (NTRS)

    Novak, Keith S.; Phillips, Charles J.; Sunada, Eric T.; Kinsella, Gary M.

    2005-01-01

    NASA launched two rovers in June and July of 2003 as a part of the Mars Exploration Rover (MER) project. MER-A (Spirit) landed on Mars in Gusev Crater at 15 degrees South latitude and 175 degree East longitude on January 4, 2004 (Squyres, et al., Dec. 2004)). MER-B (Opportunity) landed on Mars in Terra Meridiani at 2 degrees South latitude and 354 degrees East longitude on January 25, 2004 (Squyres, et al., August 2004) Both rovers have well exceeded their design lifetime (90 Sols) by more than a factor of 4. Spirit and Opportunity are still healthy and continue to execute their roving science missions at the time of this writing. This paper discusses rover flight thermal performance during the surface missions of both vehicles, covering roughly the time from the MER-A landing in late Southern Summer (Ls = 328, Sol 1A) through the Southern Winter solstice (Ls = 90, Sol 255A) to nearly Southern Vernal equinox (Ls = 160 , Sol 398A).

  18. Northern Terra Meridiani Rocks and Cliffs in 3-D

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Extended Mission operations for the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) include opportunities that come up about 10 times a week to turn and point the MGS spacecraft so that MOC can photograph a feature of high scientific interest. Many of these images are targeted to the site of a previous MOC image, so that a stereoscopic (3-D) view can be obtained.

    The stereo view, which requires red (left-eye) and blue (right-eye) 3-D glasses to be seen, covers an area approximately 2.3 km (1.4 mi) wide by 6.2 km (3.9 mi) long. The full-resolution view is seen at nearly 1.5 meters (5 ft) per pixel, a scale at which objects the size of airplanes and school buses might be seen.

    The landscape revealed by the 3-D view is a rugged terrain with steep cliffs and no fresh impact craters. This terrain seems most un-Mars-like compared to the typical cratered and dusty views MOC has provided since it began taking data in September 1997. In fact, one of the MOC science team members remarked, 'If I'd seen this landscape used in a movie about Mars five years ago, I'd have said the director had no clue what Mars is supposed to look like.' An irregular depression with a flat, mottled, light-toned floor dominates the scene. Small dark ridges on the depression floor near the top center of the image are dunes or drifts formed by wind transport of sandy sediment. The sharp buttes, mesas, and steep cliffs are all indicators that this terrain consists of a broad exposure of martian bedrock. North is up and sunlight illuminates each picture from the left/upper left.

  19. Third International Colloquium on Mars

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Abstracts of papers concerning the geology and geophysics of Mars, volcanism on Mars, the Mars atmosphere, and the long term history of the atmosphere-cap-regolith volatile regime are presented. Formation of the Mars surface, climatology, gravity and magnetism, atmospheric boundary layers, and interpretation of Viking imagery and Earth-based observations are considered.

  20. Tyrrhena Terra: hydrated lobates ejecta and plains, as seen by OMEGA/MEx

    NASA Astrophysics Data System (ADS)

    Loizeau, D.; Bouley, S.; Mangold, N.; Meresse, S.; Costard, F.; Poulet, F.; Ansan, V.; Le Mouelic, S.; Bibring, J.-P.; Gondet, B.

    2009-04-01

    Tyrrhena Terra was reported [2; 1; 3; 4] as one of the Martian region displaying outcrops rich in hydrated miner-als, by the identification of a weak 1.9 µm absorption band on spectra acquired by OMEGA, the imaging spectrometer onboard Mars Express. The region is located in cratered Noachian highlands in the southern hemisphere, south of Isidia Planitia and north of Hellas basin. It displays highland terrains partially dissected by fluvial valleys and several intercrater plains. Hydrated minerals are identified in two types of terrains in Tyrrhena Terra: on lobate ejecta blankets and in some plains. About 20 ejecta blankets showing hydrated minerals were identified with OMEGA in the studied area. The pres-ence of the 2.3 µm absorption band, together with the 1.93 µm band, indicates the possible presence of phyllosili-cates. Most of these ejecta blankets are located on the eastern, higher part of the studied region, above 2000 m in altitude. Their diameter varies from 2 to 26 km. They are well delimited and are contrasted compared to the rest of the highlands on THEMIS IR night imagery. The other, non-hydrated, ejecta blankets of the region do not show such a contrast. As the dust cover is very low throughout the region, the difference in the THEMIS IR nighttime imagery would come from a difference in the ejecta material or preservation [3]. The hydration as seen by OMEGA appears preferentially on the surrounding ejecta and not inside the crater. Py-roxene is also detected on the ejecta blankets. On another hand, most ejecta are devoid of olivine as detected by OMEGA, although it is detected on many intercrater plains of the region. In addition, CRISM observes phyllosilicates associated with crater ejecta blankets and in mounds and knobs on crater floors [5; 6]. We also identified with OMEGA around 10 areas showing outcrops of hydrated minerals in the studied region, not associated to crater ejecta. They generally correspond to plains at the end of valley

  1. Mars Equipment Transport System

    NASA Astrophysics Data System (ADS)

    Sorrells, Cindy; Geiger, Michelle; Ohanlon, Sean; Pieloch, Stuart; Brogan, Nick

    1993-12-01

    Mechanical Engineering Senior Design Project 1 (ME4182) is a part of the NASA/University Advanced Design Program. Under this program, NASA allocates money and resources to students to be used in design work for a specified topic. The current topic is the exploration and colonization of Mars. The specific area in which we are to work is the transportation of the modules in which astronauts will live while on Mars. NASA is concerned about the weight of the module transferring system, as the shipping cost to Mars is quite expensive. NASA has specified that the weight of the system is to be minimized in order to reduce the shipping costs.

  2. Mars Equipment Transport System

    NASA Technical Reports Server (NTRS)

    Sorrells, Cindy; Geiger, Michelle; Ohanlon, Sean; Pieloch, Stuart; Brogan, Nick

    1993-01-01

    Mechanical Engineering Senior Design Project 1 (ME4182) is a part of the NASA/University Advanced Design Program. Under this program, NASA allocates money and resources to students to be used in design work for a specified topic. The current topic is the exploration and colonization of Mars. The specific area in which we are to work is the transportation of the modules in which astronauts will live while on Mars. NASA is concerned about the weight of the module transferring system, as the shipping cost to Mars is quite expensive. NASA has specified that the weight of the system is to be minimized in order to reduce the shipping costs.

  3. Mars tectonics and volcanism

    NASA Technical Reports Server (NTRS)

    Solomon, Sean C.

    1990-01-01

    The focus of this research was on three broad areas: (1) the relation between lithospheric stress in the vicinity of a growing volcano and the evolution of eruption characteristics and tectonic faulting; (2) the relation between elastic lithosphere thickness and thermal structure; and (3) a synthesis of constraints on heat flow and internal dynamics on Mars. The two reports presented are: (1) Heterogeneities in the Thickness of the Elastic Lithosphere of Mars--Constraints on Heat Flow and Internal Dynamics; and (2) State of Stress, Faulting, and Eruption Characteristics of Large Volcanoes on Mars.

  4. Mars Observer's costly solitude

    NASA Astrophysics Data System (ADS)

    Travis, John

    1993-09-01

    An evaluation is presented of the ramifications of the loss of contact with the Mars Observer spacecraft in August, 1993; the Observer constituted the first NASA mission to Mars in 17 years. It is noted that most, if not all of the scientists involved with the mission will have to find alternative employment within 6 months. The loss of the Observer will leave major questions concerning the geologic history of Mars, and its turbulent atmospheric circulation, unanswered. A detailed account of the discovery of the loss of communications, the unsuccessful steps taken to rectify the problem, and the financial losses incurred through the failure of the mission, are also given.

  5. Exobiology on Mars

    NASA Technical Reports Server (NTRS)

    Devincenzi, D. L. (Editor); Marshall, J. R. (Editor); Andersen, D. (Editor)

    1990-01-01

    Descriptions of several instrument concepts that were generated during a workshop entitled, Exobiology Instrument Concepts for a Soviet Mars 94/94 Mission, held at NASA Ames Research Center in 1989 are presented. The objective was to define and describe instrument concepts for exobiology and related science that would be compatible with the mission types under discussion for the 1994 and 1996 Soviet Mars missions. Experiments that use existing technology were emphasized. The concepts discussed could also be used on U.S. missions that follow Mars Observer.

  6. Solar radiation on Mars

    NASA Technical Reports Server (NTRS)

    Appelbaum, Joseph; Flood, Dennis J.

    1989-01-01

    Detailed information on solar radiation characteristics on Mars are necessary for effective design of future planned solar energy systems operating on the surface of Mars. Presented here is a procedure and solar radiation related data from which the diurnally, hourly and daily variation of the global, direct beam and diffuse insolation on Mars are calculated. The radiation data are based on measured optical depth of the Martian atmosphere derived from images taken of the sun with a special diode on the Viking cameras; and computation based on multiple wavelength and multiple scattering of the solar radiation.

  7. Spectroscopic observation of Mars

    NASA Technical Reports Server (NTRS)

    Singer, R. B.

    1985-01-01

    A review is given of what is known about the surface of Mars from reflectance spectroscopy, including some new results and providing an overview of the principles involved. While some form of bound water and/or OH has been known on Mars for many years, a new result presented is the identification of structural OH in a dilute or poorly crystalline magnesian clay. The detection of water ice in the residual north polar cap is noted. Also considered is the role that reflectance spectroscopy will play in the future, from earth and as an important part of the NASA Mars Geosciences/Climatology Orbiter mission.

  8. Mars Aerocapture Systems Study

    NASA Technical Reports Server (NTRS)

    Wright, Henry S.; Oh, David Y.; Westhelle, Carlos H.; Fisher, Jody L.; Dyke, R. Eric; Edquist, Karl T.; Brown, James L.; Justh, Hilary L.; Munk, Michelle M.

    2006-01-01

    Mars Aerocapture Systems Study (MASS) is a detailed study of the application of aerocapture to a large Mars robotic orbiter to assess and identify key technology gaps. This study addressed use of an Opposition class return segment for use in the Mars Sample Return architecture. Study addressed mission architecture issues as well as system design. Key trade studies focused on design of aerocapture aeroshell, spacecraft design and packaging, guidance, navigation and control with simulation, computational fluid dynamics, and thermal protection system sizing. Detailed master equipment lists are included as well as a cursory cost assessment.

  9. Airbag Tracks on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The circular shapes seen on the martian surface in these images are 'footprints' left by the Mars Exploration Rover Opportunity's airbags during landing as the spacecraft gently rolled to a stop. Opportunity landed at approximately 9:05 p.m. PST on Saturday, Jan. 24, 2004, Earth-received time. The circular region of the flower-like feature on the right is about the size of a basketball. Scientists are studying the prints for more clues about the makeup of martian soil. The images were taken at Meridiani Planum, Mars, by the panoramic camera on the Mars Exploration Rover Opportunity.

  10. Solar radiation on Mars

    SciTech Connect

    Appelbaum, J.; Flood, D.J. )

    1990-01-01

    Detailed information on solar radiation characteristics on Mars are necessary for effective design of future planned solar energy systems operating on the surface of Mars. In this paper the authors present a procedure and solar radiation related data from which the diurnally, hourly and daily variation of the global, direct beam and diffuse insolation on Mars are calculated. The radiation data are based on measured optical depth of the Martian atmosphere derived from images taken of the sun with a special diode on the Viking cameras; and computation based on multiple wavelength and multiple scattering of the solar radiation.

  11. Human Exploration of Mars

    NASA Astrophysics Data System (ADS)

    Gwynne, Owen; McKay, Chris; Zubrin, Robert

    1991-06-01

    Novel approaches to the human exploration of Mars are considered with emphasis on a space suit design, extraterrestrial surface mobility, and water supply. A possible way of transporting personnel on the surface of Mars uses a suborbital rocket that will hop from one site to the next, refuelling each time it lands and giving the Martian explorers effective global mobility. Telepresence could be used to avoid limiting the people on Mars to a small exploration area as a result of a lack of transportation infrastructure. Drawings and photographs are included.

  12. Bassanite on Mars

    NASA Astrophysics Data System (ADS)

    Vaniman, D. T.; Bish, D. L.; Chipera, S. J.

    2009-03-01

    There are several ways to desiccate gypsum on Mars and form bassanite but rehydration in presence of ice at cold, dry conditions tends to form only bassanite or gypsum plus bassanite. This product may provide a paleoclimate or paleogeothermal marker.

  13. Mars Balance Challenge

    NASA Video Gallery

    The Challenge is to develop ideas for how NASA can turn available entry, descent, and landing balance mass on a future Mars mission into a scientific or technological payload. Proposed concepts sho...

  14. Mars planimetric mapping

    NASA Astrophysics Data System (ADS)

    Batson, R. M.; Bridges, P. M.; Lee, E. M.

    1985-04-01

    The 1:5,000,000 scale shaded relief maps of Mars originally compiled from Mariner 9 pictures are being upgraded by adding details visible on Viking Orbiter images. This work is done by modifying the original airbrush drawings; no attempt is made to reposition features according to the latest control nets. Thirteen of these maps have been published to date, two are in compilation, and two are in press. A hard cover atlas containing reduced scale versions of all Mars cartographic products will be published upon completion of the revisions of the 1:5,000,000 scale maps, the 1:2,000,000 scale photomosaics, and Mars color albedo mapping tasks. This atlas will supersede the existing Atlas of Mars prepared by Batson and others.

  15. Environment of Mars, 1988

    NASA Technical Reports Server (NTRS)

    Kaplan, David I. (Compiler)

    1988-01-01

    A compilation of scientific knowledge about the planet Mars is provided. Information is divided into three categories: atmospheric data, surface data, and astrodynamic data. The discussion of atmospheric data includes the presentation of nine different models of the Mars atmosphere. Also discussed are Martian atmospheric constituents, winds, clouds, and solar irradiance. The great dust storms of Mars are presented. The section on Mars surface data provides an in-depth examination of the physical and chemical properties observed at the two Viking landing sites. Bulk densities, dielectric constants, and thermal inertias across the planet are then described and related back to those specific features found at the Viking landing sites. The astrodynamic materials provide the astronomical constants, time scales, and reference coordinate frames necessary to perform flightpath analysis, navigation design, and science observation design.

  16. Mars Exploration Zones

    NASA Video Gallery

    This concept animation shows just one of many potential concepts for how the first human landing site on Mars might evolve throughout the course of multiple human expeditions to the Red Planet over...

  17. Walking on Mars

    NASA Astrophysics Data System (ADS)

    Cavagna, G. A.; Willems, P. A.; Heglund, N. C.

    1998-06-01

    Sometime in the near future humans may walk in the reduced gravity of Mars. Gravity plays an essential role in walking. On Earth, the body uses gravity to `fall forwards' at each step and then the forward speed is used to restore the initial height in a pendulum-like mechanism. When gravity is reduced, as on the Moon or Mars, the mechanism of walking must change. Here we investigate the mechanics of walking on Mars onboard an aircraft undergoing gravity-reducing flight profiles. The optimal walking speed on Mars will be 3.4 km h-1 (down from 5.5 km h-1 on Earth) and the work done per unit distance to move the centre of mass will be half that on Earth.

  18. Future Mars outpost architecture

    NASA Technical Reports Server (NTRS)

    Williams, T. D.; Owens, J.; Easter, R. W.; Mireles, O. R.; Ramsey, S. A.; Palko, C. W.

    2000-01-01

    This paper describes an outpost designed with the JPL Mars Long Range Planning Team's goals in mind. The design focuses on subsurface mapping and characterization, accomplished through seismic mapping and deep drilling.

  19. NASA's Mars Landings

    NASA Video Gallery

    This video shows the landing sites of all six NASA spacecraft to reachMars—Viking 1, Viking 2, Pathfinder, Spirit, Opportunity, Phoenix—and thetarget location where Curiosity will touch down ...

  20. Methane Plumes on Mars

    NASA Video Gallery

    Spectrometer instruments attached to several telescopes detect plumes of methane emitted from Mars during its summer and spring seasons. High levels of methane are indicated by warmer colors. The m...

  1. Mars Acoustic Anemometer

    NASA Astrophysics Data System (ADS)

    Banfield, D. J.

    2012-12-01

    We have developed a very high performance anemometer (wind gauge) for use at Mars. This instrument has great scientific as well as strategic reasons to be included on all future missions to the surface of Mars. We will discuss why we set out to develop this instrument, as well as why the previous wind sensors for Mars are insufficient to meet the scientific and strategic needs at Mars. We will also discuss how the instrument works, and how it differs from terrestrial counterparts. Additionally, we will discuss the current status of the instrument. Measuring winds at Mars is important to better understand the atmospheric circulation at Mars, as well as exchange between the surface and atmosphere. The main conduit of transport of water, and hence its current stability at any particular location on Mars is controlled by these atmospheric motions and the exchange between surface and atmosphere. Mars' large-scale winds are moderately well understood from orbital observations, but the interaction with the surface can only be addressed adequately in situ. Previous anemometers have been 2-D (with the exception of REMS on MSL) and slow response (typically <1Hz), and relatively low sensitivity/accuracy (>1 m/s). Our instrument is capable of fully 3-D measurements, with fast response (>20 Hz) and great sensitivity/accuracy (~3 cm/s). This significant step forward in performance is important for the surface-atmosphere exchanges of heat, momentum and volatiles. In particular, our instrument could directly measure the heat and momentum fluxes between surface and atmosphere using eddy-flux techniques proven terrestrially. When combined with a fast response volatile analysis instrument (e.g., a TLS) we can also measure eddy fluxes of volatile transport. Such a study would be nearly impossible to carry out with preceding anemometers sent to Mars with insufficient response time and sensitivity to adequately sample the turbulent eddies. Additionally, our instrument, using acoustics

  2. Mars Exploration Rover Mission

    NASA Technical Reports Server (NTRS)

    Cohen, Barbara A.

    2008-01-01

    This viewgraph presentation reviews the Mars Exploration Rover Mission. The design of the Rover along with the Athena science payload is also described. Photographs of the Gusev Crater and Meridiani rocks are also shown.

  3. Mars Express & Co

    NASA Astrophysics Data System (ADS)

    Borgeest, Ulf; Staude, Jakob; Kratzenber-Annies, Volker; Coradini, Marcello; Flury, Walter; Jaumann, Ralf; Neukum, Gerhard; Ongaro, Franco; Lemke, Dietrich; Althaus, Tilmann; Fuhrmeister, Birgit

    Contents: Europa und der übrige Kosmos. Der Weltraum und das öffentliche Interesse an ihm. Europa besucht Mars. INTEGRAL - Blick ins Herz der Galaxis. ISO - Von der Idee zum Instrument. Dienstreisen ins All. ENVISAT.

  4. Retrograde Motion of Mars.

    ERIC Educational Resources Information Center

    Knappenberger, Paul H.

    1979-01-01

    Presents an activity whereby students describe the path of Mars through a background starfield. Includes purpose, materials, pre-lab, and procedure. Also provides guidelines for making a dial-a-planet wheel. (MA)

  5. The conquest of Mars

    NASA Astrophysics Data System (ADS)

    David, L. W.

    1984-08-01

    Concepts for a manned mission to Mars have been examined as early as 1962. In 1969, NASA studies showed Apollo moon technology to be adequate for a 600-day flight with a proposed landing for 1982. However, financial drain, shifting economic priorities and a downgrading of the 'space race' in the late 1960s contributed to the downfall of the project. The successful Mariner and Viking missions of the 1970s have enhanced understanding of the planet, and in the wake of these flights, numerous studies have been made for future unmanned missions. Some suggested projects include a Mars Orbiter, sensor outposts, a mobile lander, A Mars' Air Force', and a return sample mission. Following a full unmanned reconnaissance of the planet, advances in space propulsion, refuelling and large scale construction, a manned voyage to Mars could be achieved.

  6. Environment of Mars, 1988

    SciTech Connect

    Kaplan, D.I.

    1988-10-01

    A compilation of scientific knowledge about the planet Mars is provided. Information is divided into three categories: atmospheric data, surface data, and astrodynamic data. The discussion of atmospheric data includes the presentation of nine different models of the Mars atmosphere. Also discussed are Martian atmospheric constituents, winds, clouds, and solar irradiance. The great dust storms of Mars are presented. The section on Mars surface data provides an in-depth examination of the physical and chemical properties observed at the two Viking landing sites. Bulk densities, dielectric constants, and thermal inertias across the planet are then described and related back to those specific features found at the Viking landing sites. The astrodynamic materials provide the astronomical constants, time scales, and reference coordinate frames necessary to perform flightpath analysis, navigation design, and science observation design.

  7. Mars' Inner Core

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This figure shows a cross-section of the planet Mars revealing an inner, high density core buried deep within the interior. Dipole magnetic field lines are drawn in blue, showing the global scale magnetic field that one associates with dynamo generation in the core. Mars must have one day had such a field, but today it is not evident. Perhaps the energy source that powered the early dynamo has shut down. The differentiation of the planet interior - heavy elements like iron sinking towards the center of the planet - can provide energy as can the formation of a solid core from the liquid.

    The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. JPL is an operating division of California Institute of Technology (Caltech).

  8. Internal constitution of Mars.

    NASA Technical Reports Server (NTRS)

    Anderson, D. L.

    1972-01-01

    Models of the internal structure of Mars consistent with the mass, radius and moment of inertia of the planet are constructed. The models assume that the radius of the core is between 0.36 and 0.60 of the radius of the planet, that the zero-pressure density of the mantle is between 3.54 and 3.49 g/cu cm, and that the planet contains 25 to 28% iron. Meteorite models of Mars containing 25 wt % iron and 12 wt % core are also proposed. It is maintained that Mars in contrast to the earth is an incompletely differentiated planet with a core substantially richer in sulfur than the core of the earth. The absence of a magnetic field on Mars is possibly linked with lack of lunar precessional torque and the small size and high resistivity of the Martian core.

  9. Explore Mars With Curiosity

    NASA Video Gallery

    This animation shows the approximate true position of NASA’s Curiosityrover on Mars. A 3-D virtual model of Curiosity is shown inside GaleCrater, near Mount Sharp, Curiosity’s ultimate destin...

  10. The Cruise to Mars

    NASA Video Gallery

    The long journey to Mars through the harsh environment of spaceconfronts the Curiosity navigation team with a long list of challengesto get the spacecraft safely to its destination.› Mission site

  11. Mars Express - Over 10 Years in Orbit Around Mars

    NASA Astrophysics Data System (ADS)

    Chicarro, Agustin; Svedhem, Hakan

    2014-05-01

    The ESA Mars Express mission was launched more than a decade ago, reaching its working orbit around Mars in January 2004. All the instruments and subsystems onboard the spacecraft are still in working order. As the first European planetary mission, Mars Express has been providing exciting new scientific results on all fields of Mars science, including the interior structure of the planet, its surface mineralogy and geological processes, its atmospheric dynamics and chemistry, the interaction of its upper atmosphere with the solar wind, as well as the geodesy of its satellite Phobos. Also, Mars Express has contributed to pave the way for future European Mars Exploration, including the Trace Gas Orbiter to be launched in 2016, the ExoMars rover in 2018 and further exploration in 2020 and beyond. Among the abundant Mars Express scientific results, the Top-10 scientific highlights of the mission will be presented, addressing all areas of Mars investigation from orbit.

  12. Status of MARS Code

    SciTech Connect

    N.V. Mokhov

    2003-04-09

    Status and recent developments of the MARS 14 Monte Carlo code system for simulation of hadronic and electromagnetic cascades in shielding, accelerator and detector components in the energy range from a fraction of an electronvolt up to 100 TeV are described. these include physics models both in strong and electromagnetic interaction sectors, variance reduction techniques, residual dose, geometry, tracking, histograming. MAD-MARS Beam Line Build and Graphical-User Interface.

  13. A Mars 1984 mission

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Mission objectives are developed for the next logical step in the investigation of the local physical and chemical environments and the search for organic compounds on Mars. The necessity of three vehicular elements: orbiter, penetrator, and rover for in situ investigations of atmospheric-lithospheric interactions is emphasized. A summary report and committee recommendations are included with the full report of the Mars Science Working Group.

  14. 2001 Mars Odyssey Mission

    NASA Technical Reports Server (NTRS)

    Varghese, Philip

    2008-01-01

    This viewgraph presentation reviews the 2001 Mars Odyssey Mission. The contents include: 1) Mission Overview; 2) Current Scope of Work: 3) Facilities; 4) Critical Role of DSN; 5) Relay as Mission Supplement; 6) Current Mars Telecom Infrastructure; 7) PHX EDL Comm Overview; 8) EDL Geometry (Entry through Landing); 9) Phoenix Support; 10) Preparations for Phoenix; 11) EDL Support Timeline; 12) One Year Rolling Schedule; 13) E3 Rationale; and 14) Spacecraft Status.

  15. Mars Pathfinder [foldout].

    PubMed

    1997-12-01

    The following foldout present images and analysis from the Mars Pathfinder Mission that are discussed in seven subsequent Reports. The center is a four-page panorama of the surface of Mars around the lander (Plate 1). The back of the foldout contains surface images (Plate 7), a different perspective of the landing site (Plate 2), rover targets (Plate 3), locations of rocks and other features (Plate 6) and data analysis (Plates 4, 4, 8, 9, and 10). PMID:9411794

  16. Salt weathering on Mars

    NASA Technical Reports Server (NTRS)

    Malin, M. C.

    1974-01-01

    Mariner 9 photographs of Mars indicate that significant erosion has occurred on that planet. Although several possible erosion mechanisms have been proposed, most terrestrial weathering mechanisms cannot function in the present Martian environment. Salt weathering, believed to be active in the Antarctic dry valleys, is especially suited to Mars, given the presence of salts and small amounts of water. Volcanic salts are probably available, and the association of salts and water is likely from both thermodynamic and geologic considerations.

  17. Discovery concepts for Mars

    NASA Technical Reports Server (NTRS)

    Luhmann, J. G.; Russell, C. T.; Brace, L. H.; Nagy, A. F.; Jakosky, B. M.; Barth, C. A.; Waite, J. H.

    1992-01-01

    Two focused Mars missions that would fit within the guidelines for the proposed Discovery line are discussed. The first mission would deal with the issue of the escape of the atmosphere (Mars') to space. A complete understanding of this topic is crucial to deciphering the evolution of the atmosphere, climate change, and volatile inventories. The second mission concerns the investigation of remanent magnetization of the crust and its relationship to the ionosphere and the atmosphere.

  18. Why exobiology on Mars?

    NASA Astrophysics Data System (ADS)

    Brack, A.

    1996-11-01

    Processing of organic molecules by liquid water was probably an essential requirement towards the emergence of terrestrial primitive life. According to Oparin's hypothesis, organic building blocks required for early life were produced from simple organic molecules formed in a primitive reducing atmosphere. Geochemists favour now a less reducing atmosphere dominated by carbon dioxide. In such an atmosphere very few building blocks are formed. Import of extra-terrestrial organic molecules may represent an alternative supply. Experimental support for such an alternative scenario is examined in comets, meteorites and micrometeorites. The early histories of Mars and Earth clearly show similarities. Liquid water was once stable on the surface of Mars attesting the presence of an atmosphere capable of deccelerating C-rich micrometeorites. Therefore, primitive life may have developed on Mars as well. Liquid water disappeared from the surface of Mars very early, about 3.8 Ga ago. The Viking missions did not find, at the surface of the Martian soil, any organic molecules or clear-cut evidence for microbial activities such as photo-synthesis, respiration or nutrition. The results can be explained referring to an active photochemistry of Martian soil driven by the high influx of solar UV. These experiments do not exclude the existence of organic molecules and fossils of micro-organisms which developed on early Mars until liquid water disappeared. Mars may store below its surface some well preserved clues of a still hypothetical primitive life.

  19. Paleolakes on Mars

    NASA Technical Reports Server (NTRS)

    Wharton, R. A. Jr; Crosby, J. M.; McKay, C. P.; Rice, J. W. Jr; Wharton RA, ,. J. r. (Principal Investigator)

    1995-01-01

    Observational evidence such as outflow channels and valley networks suggest that in the past there was flowing water on Mars. The images of fluvial features on Mars logically suggest that there must exist downstream locations in which the water pooled and the sediment load deposited (i.e. lakes). Sediments and morphological features associated with the martian paleolakes are believed to occur in Valles Marineris, and several large basins including Amazonis, Chryse and Elysium planitia. As Mars became progressively colder over geological time, any lakes on its surface would have become seasonally, and eventually perennially ice-covered. We know from polar lakes on Earth that ice-covered lakes can persist even when the mean annual temperature falls below freezing. Thus, the most recent lacustrine sediments on Mars were probably deposited in ice-covered lakes. While life outside of the Earth's atmosphere has yet to be observed, there is a general consensus among exobiologists that the search for extraterrestrial life should be based upon liquid water. The inference that there was liquid water on Mars during an earlier epoch is the primary motivation for considering the possibility of life during this time. It would be of enormous interest from both an exobiological and paleolimnological perspective to discover lakes or the evidence of former lakes on another planet such as Mars. Limnology would then become an interplanetary science.

  20. The Mars Observer database

    NASA Technical Reports Server (NTRS)

    Albee, Arden L.

    1988-01-01

    Mars Observer will study the surface, atmosphere, and climate of Mars in a systematic way over an entire Martian year. The observations of the surface will provide a database that will be invaluable to the planning of a future Mars sample return mission. Mars Observer is planned for a September 1992 launch from the Space Shuttle, using an upper-stage. After the one year transit the spacecraft is injected into orbit about Mars and the orbit adjusted to a near-circular, sun-synchronous low-altitude, polar orbit. During the Martian year in this mapping orbit the instruments gather both geoscience data and climatological data by repetitive global mapping. The scientific objectives of the mission are to: (1) determine the global elemental and mineralogical character of the surface material; (2) define globally the topography and gravitational field; (3) establish the nature of the magnetic field; (4) determine the time and space distribution, abundance, sources, and sinks of volatile material and dust over a seasonal cycle; and (5) explore the structure and aspects of the circulation of the atmosphere. The science investigations and instruments for Mars Observer have been chosen with these objectives in mind. These instruments, the principal investigator or team leader and the objectives are discussed.

  1. Transportation: Destination Mars

    NASA Technical Reports Server (NTRS)

    Eoff, Bill

    1998-01-01

    As the agency space transportation lead center, Marshall Space Flight Center has been conducting transportation assessments for future robotic and human Mars missions to identify critical technologies. Five human Mars options are currently under assessment with each option including all transportation requirements from Earth to Mars and return. The primary difference for each option is the propulsion source from Earth to Mars. In case any of the options require heavy launch capability that is not currently projected as available, an in-house study has been initiated to determine the most cost effective means of providing such launch capability. This assessment is only considering launch architectures that support the overall human Mars mission cost goal of $25B. The guidelines for the launch capability study included delivery of 80 metric ton (176 KLB) payloads, 25 feet diameter x 92 feet long, to 220 nmi orbits at 28.5 degrees. The launch vehicle concept of the study was designated "Magnum" to differentiate from prior heavy launch vehicle assessments. This assessment along with the assessment of options for all transportation phases of a Mars mission are on-going.

  2. Life on Mars

    NASA Technical Reports Server (NTRS)

    McKay, Christopher P.; Cuzzi, Jeffrey (Technical Monitor)

    1996-01-01

    Although the Viking results may indicate that Mars has no life today, the possibility exists that Mars may hold the best record of the events that led to the origin of life. There is direct geomorphological evidence that in the past Mars had large amounts of liquid water on its surface. Atmospheric models would suggest that this early period of hydrological activity was due to the presence of a thick atmosphere and the resulting warmer temperatures. From a biological perspective the existence of liquid water, by itself motivates the question of the origin of life on Mars. From studies of the Earth's earliest biosphere we know that by 3.5 Gyr. ago, life had originated on Earth and reached a fair degree of biological sophistication. Surface activity and erosion on Earth make it difficult to trace the history of life before the 3.5 Gyr timeframe. If Mars did maintain a clement environment for longer than it took for life to originate on Earth, then the question of the origin of life on Mars follows naturally.

  3. Mars Rover RTG Study

    SciTech Connect

    Schock, Alfred

    1989-11-27

    This report summarizes the results of a Radioisotope Thermoelectric Generator (RTG) design study conducted by Fairchild Space Company at the direction of the U.S. Department of Energy's Office of Special Applications, in support of the Mars Rover and Sample Return mission under investigation at NASA's Jet Propulsion Laboratory. Presented at the 40th Congress of the IAF, Oct. 7-13, 1989 in Torremolinos, Malaga-Spain. The paper describes the design and analysis of Radioisotope Thermoelectric Generators (RTGs) for powering the Mars Rover vehicle, which is a critical element of the unmanned Mars Rover and Sample Return mission (MRSR). The RTG design study was conducted by Fairchild Space for the U.S. DOE in support of the JPL MRSR Project. The paper briefly describes a reference mission scenario, an illustrative Rover design and activity pattern on Mars, and its power system requirements and environmental constraints, including the RTG cooling requirements during transit to Mars. It summarizes the baseline RTG's mass breakdown, and presents a detailed description of its thermal, thermoelectric, and electrical analysis. The results presented show the RTG performance achievable with current technology, and the performance improvements that would be achievable with various technology developments. It provides a basis for selecting the optimum strategy for meeting the Mars Rover design goals with minimal programmatic risk and cost. Cross Reference CID #7135 dated 10/1989. There is a duplicate copy. This document is not relevant to the OSTI Library. Do not send.

  4. Retrieval of Aerosol Properties from MODIS Terra, MODIS Aqua, and VIIRS SNPP: Calibration Focus

    NASA Technical Reports Server (NTRS)

    Levy, Robert C.; Mattoo, Shana; Sawyer, Virginia; Kleidman, Richard; Patadia, Falguni; Zhou, Yaping; Gupta, Pawan; Shi, Yingxi; Remer, Lorraine; Holz, Robert

    2016-01-01

    MODIS-DT Collection 6 - Aqua/Terra level 2, 3; entire record processed - "Trending" issues reduced - Still a 15% or 0.02 Terra vs Aqua offset. - Terra/Aqua convergence improved with C6+, but bias remains. - Other calibration efforts yield mixed results. VIIRS-­-DT in development - VIIRS is similar, yet different then MODIS - With 50% wider swath, VIIRS has daily coverage - Ensures algorithm consistency with MODIS. - Currently: 20% NPP vs Aqua offset over ocean. - Only small bias (%) over land (2012-­-2016) - Can VIIRS/MODIS create aerosol CDR? Calibration for MODIS - VIIRS continues to fundamentally important. It's not just Terra, or just Aqua, or just NPP-­-VIIRS, I really want to push synergistic calibration.

  5. NASA's Terra Spacecraft Eyes Smoke Plumes from Massive Rim Fire Near Yosemite

    Atmospheric Science Data Center

    2014-05-15

    ... NASA's Terra Spacecraft Eyes Smoke Plumes from Massive Rim Fire Near Yosemite     View ... Image (TIFF)   This visible image of California's Rim Fire was acquired Aug. 23, 2013 by the Multi-angle Imaging ...

  6. Official portrait of STS-44 Terra Scout payload specialist Thomas J. Hennen

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Official portrait of STS-44 Atlantis, Orbiter Vehicle (OV) 104, Terra Scout payload specialist Thomas J. Hennen wearing blue flight suit, holding space shuttle model, and seated in front of flag backdrop.

  7. Technology Demonstration Summary: Terra Vac In Situ Vacuum Extraction System, Groveland, Massachusetts

    EPA Science Inventory

    Terra Vac Inc's vacuum extraction system was demonstrated at the Valley Manufactured Products Company, Inc., site in Groveland, Massachusetts. The property is part of the Groveland Wells Superfund site and is contaminated mainly by trichloroethylene (TCE). Vacuum extraction...

  8. Development of Terra Harvest compliant plug-ins for McQ Unattended Ground Sensors (UGS)

    NASA Astrophysics Data System (ADS)

    Roeder, Brent W.; Fish, Robert C.

    2013-05-01

    The Army Research Lab (ARL), in collaboration with the Defense Intelligence Agency (DIA) and representatives from industry, recently validated the feasibility of the Terra Harvest architecture by successfully integrating dozens of Intelligence, Surveillance, and Reconnaissance (ISR) assets at the Trident Spectre 12 (TS12) exercise in Fort Story, VA. Based on the exercise, it is evident that Terra Harvest will greatly simplify the process of integrating disparate ISR systems. By reducing this complexity, Terra Harvest will increase the variety of devices U.S. soldiers have at their disposal giving them a greater technological advantage over their adversaries than ever before. This paper describes McQ's effort to develop Terra Harvest compliant plug-ins for its UGS along with lessons learned from their demonstration at TS12.

  9. Stigmatization of persons with HIV/AIDS in Saudi Arabia.

    PubMed

    Badahdah, Abdallah M

    2010-10-01

    Data about the stigmatization of persons living with HIV/AIDS in Saudi Arabia are scarce. Recent statistics from Saudi Ministry of Health showed that 77% of HIV-positive Saudis were males. The present study analyzed data from 162 Saudi male college students. The findings suggest that students who knew less about HIV/AIDS were more likely to stigmatize persons living with HIV/AIDS than those who knew more. Neither degree of religiosity nor worry about HIV infection was related to AIDS stigma. However, AIDS-related shame was the best predictor of AIDS stigma. The findings of this study point to important suggestions for AIDS prevention programs in Saudi Arabia. PMID:20592063

  10. Electronic Lab Information Exchange (ELIE) in Saudi Arabia.

    PubMed

    Al Saleem, Nouf; El Metwally, Ashraf; Househ, Mowafa

    2014-01-01

    The purpose of this paper is to discuss the Saudi experience in implementing Electronic Lab Information Exchange (ELIE) within healthcare organizations in Saudi Arabia. This paper reviews the benefits, challenges and achievements that Saudi Arabia has gone through over the last five years in implementing ELIE. Data sources included academic literature, websites, and informant interviews. Results show that various Saudi healthcare organizations are participating in ELIE and improvements in laboratory department workflow and patient care have been reported. Future work includes projects to be implemented in different laboratories within the Kingdom to link the various laboratory information systems to Electronic Health Records. Various challenges stand in the way of implementing ELIE including weakness of the information infrastructure, staff resistance, recruiting qualified staff to develop and implement ELIE, producing clear policy and procedures to ensure staff compliance with the data entry, ensuring the privacy and integrity of patient data, and the lack of awareness on the importance of ELIE. PMID:25000034

  11. Factors that influence women's nutrition knowledge in Saudi Arabia.

    PubMed

    Mansour, A A; Hassan, S A

    1994-01-01

    We studied knowledge of nutritional needs during pregnancy and lactation in 150 pregnant Saudi women at three primary health care centers in Riyadh, Saudi Arabia. We used an interview schedule to collect data regarding the women's knowledge and to determine the effects of certain independent variables on the knowledge scores. Green et al.'s (1980) PRECEDE model provided the theoretical framework for the study. Descriptive statistics, t test, and chi-square methods were used to analyze the data. The majority of the women had poor nutrition knowledge scores, with no significant differences among the three centers. A positive relationship was found between knowledge score and educational level. Negative relationships were found between knowledge score and number of pregnancies, number of deliveries, and number of living children. The findings have several implications for efforts to improve the health status of women in Saudi Arabia. PMID:8002417

  12. Katabatic wind forcing of the Terra Nova Bay polynya

    NASA Astrophysics Data System (ADS)

    Bromwich, David H.; Kurtz, Dennis D.

    The Terra Nova Bay polynya is a perennial winter feature in the western Ross Sea, Antarctica, which occupies roughly 1000 km2, it is formed and maintained by the combined influence of persistent katabatic winds, which advect newly formed bay ice eastward, and the Drygalski Ice Tongue, which prevents northward drifting pack ice from entering Terra Nova Bay. Existence of anomalously strong katabatic drainage along this coast is predicted by Parish's (1982) simulation of wintertime airflow which reveals a pronounced confluence of surface winds upslope from the Reeves Glacier where the winds are further focused by local topography. The simulation is strongly supported by regional sastrugi orientations. Average wintertime atmospheric conditions and ice sheet topography which control surface air drainage are stable on a climatic time scale; therefore, persistent wintertime katabatic winds should be an annual phenomenon. Further evidence comes from multi-year Landsat images which consistently show windswept, snowfree areas on the Reeves Glacier. In marked contrast to typical Antarctic katabatic winds, strong persistent winter winds are observed at sea level ˜25 km beyond the coastal slope break. Air probably descends as bora-type winds and is likely to be significantly denser than the air at sea level; conditions are not favorable for hydraulic jumps apparently typical of other katabatic regimes. The horizontal density difference is maintained during airflow across the Nansen Ice Sheet because relatively little air mass modification occurs there in contrast to situations where air moves over an ice-laden ocean. Observations thus suggest that katabatic winds maintain their identity for some distance seaward of the coast; qualitative trajectory calculations indicate that for representative geostrophic conditions this distance is on the order of the observed polynya width. Estimated ice freezing rates are ˜20 cm day-1, but wind-generated waves and currents prevent ice from

  13. TerraFERMA: Harnessing Advanced Computational Libraries in Earth Science

    NASA Astrophysics Data System (ADS)

    Wilson, C. R.; Spiegelman, M.; van Keken, P.

    2012-12-01

    Many important problems in Earth sciences can be described by non-linear coupled systems of partial differential equations. These "multi-physics" problems include thermo-chemical convection in Earth and planetary interiors, interactions of fluids and magmas with the Earth's mantle and crust and coupled flow of water and ice. These problems are of interest to a large community of researchers but are complicated to model and understand. Much of this complexity stems from the nature of multi-physics where small changes in the coupling between variables or constitutive relations can lead to radical changes in behavior, which in turn affect critical computational choices such as discretizations, solvers and preconditioners. To make progress in understanding such coupled systems requires a computational framework where multi-physics problems can be described at a high-level while maintaining the flexibility to easily modify the solution algorithm. Fortunately, recent advances in computational science provide a basis for implementing such a framework. Here we present the Transparent Finite Element Rapid Model Assembler (TerraFERMA), which leverages several advanced open-source libraries for core functionality. FEniCS (fenicsproject.org) provides a high level language for describing the weak forms of coupled systems of equations, and an automatic code generator that produces finite element assembly code. PETSc (www.mcs.anl.gov/petsc) provides a wide range of scalable linear and non-linear solvers that can be composed into effective multi-physics preconditioners. SPuD (amcg.ese.ic.ac.uk/Spud) is an application neutral options system that provides both human and machine-readable interfaces based on a single xml schema. Our software integrates these libraries and provides the user with a framework for exploring multi-physics problems. A single options file fully describes the problem, including all equations, coefficients and solver options. Custom compiled applications are

  14. Automated inundation monitoring using TerraSAR-X multitemporal imagery

    NASA Astrophysics Data System (ADS)

    Gebhardt, S.; Huth, J.; Wehrmann, T.; Schettler, I.; Künzer, C.; Schmidt, M.; Dech, S.

    2009-04-01

    The Mekong Delta in Vietnam offers natural resources for several million inhabitants. However, a strong population increase, changing climatic conditions and regulatory measures at the upper reaches of the Mekong lead to severe changes in the Delta. Extreme flood events occur more frequently, drinking water availability is increasingly limited, soils show signs of salinization or acidification, species and complete habitats diminish. During the Monsoon season the river regularly overflows its banks in the lower Mekong area, usually with beneficial effects. However, extreme flood events occur more frequently causing extensive damage, on the average once every 6 to 10 years river flood levels exceed the critical beneficial level X-band SAR data are well suited for deriving inundated surface areas. The TerraSAR-X sensor with its different scanning modi allows for the derivation of spatial and temporal high resolved inundation masks. The paper presents an automated procedure for deriving inundated areas from TerraSAR-X Scansar and Stripmap image data. Within the framework of the German-Vietnamese WISDOM project, focussing the Mekong Delta region in Vietnam, images have been acquired covering the flood season from June 2008 to November 2008. Based on these images a time series of the so called watermask showing inundated areas have been derived. The product is required as intermediate to (i) calibrate 2d inundation model scenarios, (ii) estimate the extent of affected areas, and (iii) analyze the scope of prior crisis. The image processing approach is based on the assumption that water surfaces are forward scattering the radar signal resulting in low backscatter signals to the sensor. It uses multiple grey level thresholds and image morphological operations. The approach is robust in terms of automation, accuracy, robustness, and processing time. The resulting watermasks show the seasonal flooding pattern with inundations starting in July, having their peak at the end

  15. Radiometric cross-calibration of Terra ASTER and MODIS

    NASA Astrophysics Data System (ADS)

    Yuan, Karen; Thome, Kurt; McCorkel, Joel

    2015-09-01

    Calibration and validation play an essential role during the acquisition and processing of satellite data for Earth Observing System satellites in addition to being an integral part of maintaining scientific values of archived satellite data. The Advanced Spaceborne Thermal Emission and Reflection and Radiometer (ASTER) and Moderate Resolution Imaging Spectroradiometer (MODIS) are two of five sensors onboard the Terra platform. ASTER has a swath width of 60 km with 8 spectral bands in the visible and near infrared (VNIR) and thermal infrared (TIR) spectral range with a spatial resolution of 15-m (bands 1-3) and 90-m (bands 10-14), respectively while MODIS has a swath width of 2300 km with 36 spectral bands from visible to infrared spectral range with a spatial resolution of 250 m (bands 1-2), 500 m (bands 3-7), and 1 km (bands 8-36). ASTER is the `zoom' lens and MODIS is the `keystone' instrument for Terra; they provide quantitative measurements of various earth system variables to the scientific and to the broader community. The simultaneous view of the sensors simplifies the intercomparison between them and the current work relies on the use of the Railroad Valley Playa test site to reduce uncertainties caused by spatial heterogeneity and spectral differences in the sensors. The fact that Railroad Valley is a calibration test site for ASTER ensures that ASTER was tasked at a higher rate over this area providing more scenes for an intercomparison. The study compares ASTER L1B data for the three VNIR bands reprocessed with recent calibration updates and MODIS 02 Collection 6 data products for the similar bands. No correction for geometry angle is needed and coincident 3-km by 3-km regions are used to reduce the impact of spatial heterogeneity. A correction for spectral differences between the sensors is applied based on seasonal averages of EO-1 Hyperion spectral range. Results indicate that the calibrated radiance products from the two sensors agree to within the

  16. Molecular epidemiology of adenoviral keratoconjunctivitis in Saudi Arabia

    PubMed Central

    Omar, Nazri; Hammouda, Ehab; Akanuma, Masataka; Ohguchi, Takeshi; Ariga, Toshihide; Tagawa, Yoshitsugu; Kitaichi, Nobuyoshi; Ishida, Susumu; Aoki, Koki; Ishiko, Hiroaki; Ohno, Shigeaki

    2010-01-01

    Purpose Adenoviral keratoconjunctivitis is a major cause of ocular morbidity and may lead to visual loss. Adenovirus types 8, 19, and 37 may cause epidemic keratoconjunctivitis. The main objective of this study was to determine the types of adenoviruses causing keratoconjunctivitis in Saudi Arabia. Methods We conducted a non-interventional observational clinical study. Seventy three eyes from 65 patients who presented to The Eye Center in Riyadh, Saudi Arabia with clinical features of acute adenoviral keratoconjunctivitis were included. Each patient underwent complete clinical examination and features such as membranous reaction, conjunctival hemorrhage, subepithelial corneal infiltrates, and preauricular lymph node enlargement were recorded. Conjunctival swabs were obtained from patients with presumed acute viral conjunctivitis. Immunochromatography (IC) and restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) were performed on the conjunctival swabs obtained from each eye. Serotype identification was performed using direct sequencing technique. Results Forty-nine (67.1%) were adenovirus type 8, 8 (11.0%) were adenovirus type 3, 6 (8.2%) type 37, 5 (6.8%) were adenovirus type 4, and 2 (2.3%) type 19. The remaining 5 were types 14, 19, and 22. The prevalence of membranous conjunctivitis was highest (83%) among eyes with adenovirus type 37 while subepithelial corneal opacities were most commonly seen among eyes with adenovirus type 8 (47%). Immunochromatography tests were positive for adenovirus in 48 (65.7%) out of 73 eyes. Conclusions This study determined the types of adenoviruses causing keratoconjunctivitis at one center in Saudi Arabia. Direct sequencing techniques is an efficient, accurate, and rapid means of diagnosing adenoviral keratoconjunctivitis. The most common causes of adenoviral keratoconjunctivitis in Saudi Arabia were adenovirus types 8, 3, and 37. Membranous conjunctivitis and subepithelial opacities had the highest

  17. Geological mapping in northwestern Saudi Arabia using LANDSAT multispectral techniques

    NASA Technical Reports Server (NTRS)

    Blodget, H. W.; Brown, G. F.; Moik, J. G.

    1975-01-01

    Various computer enhancement and data extraction systems using LANDSAT data were assessed and used to complement a continuing geologic mapping program. Interactive digital classification techniques using both the maximum-likelihood and thresholding statistical approaches achieve very limited success in areas of highly dissected terrain. Computer enhanced imagery developed by color compositing stretched MSS ratio data was constructed for a test site in northwestern Saudi Arabia. Initial results indicate that several igneous and sedimentary rock-types can be discriminated.

  18. Geological mapping in northwestern Saudi Arabia using LANDSAT multispectral techniques

    NASA Technical Reports Server (NTRS)

    Blodget, H. W.; Brown, G. F.; Moik, J. G.

    1975-01-01

    Various computer enhancement and data extraction systems using LANDSAT data were assessed and used to complement a continuing geologic mapping program. Interactive digital classification techniques using both the parallel-piped and maximum-likelihood statistical approaches achieve very limited success in areas of highly dissected terrain. Computer enhanced imagery developed by color compositing stretched MSS ratio data was constructed for a test site in northwestern Saudi Arabia. Initial results indicate that several igneous and sedimentary rock types can be discriminated.

  19. Desert Wadis and Smoke from Kuwait Oil Fires, Saudi Arabia

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Smoke from the Kuwait Oil Fires obscures the view of the desert wadis, Saudi Arabia (29.5N, 42.5E). During the brief Gulf war between Iraq and the Allied forces, many of the oil wells in Kuwait were destroyed and set afire. For several months, those fires burned out of control, spewing smoke and ash for hundreds of miles in many directions depending on the altitude, time of year and the prevailing winds.

  20. An Increase of Intelligence in Saudi Arabia, 1977-2010

    ERIC Educational Resources Information Center

    Batterjee, Adel A.; Khaleefa, Omar; Ali, Khalil; Lynn, Richard

    2013-01-01

    Normative data for 8-15 year olds for the Standard Progressive Matrices in Saudi Arabia were obtained in 1977 and 2010. The 2010 sample obtained higher average scores than the 1977 sample by 0.78d, equivalent to 11.7 IQ points. This represents a gain of 3.55 IQ points a decade over the 33 year period. (Contains 1 table.)

  1. Developmental oral anomalies among schoolchildren in Gizan region, Saudi Arabia.

    PubMed

    Salem, G; Holm, S A; Fattah, R; Basset, S; Nasser, C

    1987-06-01

    The present report gives prevalence values for some developmental oral anomalies in 1932 schoolchildren aged 6-12 yr in Gizan region, Saudi Arabia. The developmental oral anomalies identified in this study were: torus palatinus (1.4%), fissured tongue (0.8%), geographic tongue (0.2%), and tongue tie (0.1%). None of the following developmental oral anomalies were observed: lip pits, cleft lip and/or palate, torus mandibularis, microglossia, macroglossia or median rhomboid glossitis. PMID:3474099

  2. Hubble Captures A Full Rotation Of Mars

    NASA Technical Reports Server (NTRS)

    1997-01-01

    impact basin, Hellas (near bottom of right-hand image), but a diffuse haze covers much of the Martian tropics as well.

    The familiar bright and dark markings on the Martian surface are most obvious in images taken through red and near-infrared filters. These images clearly reveal the large, dark, circular 'sea' of sand dunes (Olympia Planitia) that surrounds the north pole, as well a number of other familiar features, including the giant Tharsis volcanos. The 16-mile (27 km) high Olympus Mons is near the center of the left-hand image, with Arsia, Povonis, and Ascraeus Mons forming a south-west to north-east line just to its right. The volcano, Elysium Mons is near the center of the middle image. The prominent dark feature just below the center on the disk on the rightmost image is Syrtis Major Planitia.

    Hubble is being used to monitor dust storm activity to support the Mars Pathfinder and Mars Global Surveyor Orbiter Missions, which are currently en route to Mars. Airborne dust is most easily seen in WFPC2's red and near-infrared images. Weather reports derived from these observations are particularly valuable for Mars Pathfinder, which is scheduled for a July 4, 1997 landing on the red planet. A preliminary analysis of these HST data reveals enhanced dust activity over the dark Vastitas Borealis region in the northern hemisphere, and over the Noachis Terra and Terra Tyrrhena regions just south of the Martian equator. There is also evidence for airborne dust and ice clouds in the Hellas basin. However, these images show no evidence for large-scale dust storm activity.

    This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  3. Tectonics and volcanism of Eastern Aphrodite Terra, Venus - No subduction, no spreading

    NASA Technical Reports Server (NTRS)

    Hansen, Vicki L.; Phillips, Roger J.

    1993-01-01

    Eastern Aphrodite Terra, a deformed region with high topographic relief on Venus, has been interpreted as analogous to a terrestrial extensional or convergent plate boundary. However, analysis of geological and structural relations indicates that the tectonics of eastern Aphrodite Terra is dominated by blistering of the crust by magma diapirs. The findings imply that, within this region, vertical tectonism dominates over horizontal tectonism and, consequently, that this region is neither a divergent nor a convergent plate boundary.

  4. The MARS2013 Mars analog mission.

    PubMed

    Groemer, Gernot; Soucek, Alexander; Frischauf, Norbert; Stumptner, Willibald; Ragonig, Christoph; Sams, Sebastian; Bartenstein, Thomas; Häuplik-Meusburger, Sandra; Petrova, Polina; Evetts, Simon; Sivenesan, Chan; Bothe, Claudia; Boyd, Andrea; Dinkelaker, Aline; Dissertori, Markus; Fasching, David; Fischer, Monika; Föger, Daniel; Foresta, Luca; Fritsch, Lukas; Fuchs, Harald; Gautsch, Christoph; Gerard, Stephan; Goetzloff, Linda; Gołebiowska, Izabella; Gorur, Paavan; Groemer, Gerhard; Groll, Petra; Haider, Christian; Haider, Olivia; Hauth, Eva; Hauth, Stefan; Hettrich, Sebastian; Jais, Wolfgang; Jones, Natalie; Taj-Eddine, Kamal; Karl, Alexander; Kauerhoff, Tilo; Khan, Muhammad Shadab; Kjeldsen, Andreas; Klauck, Jan; Losiak, Anna; Luger, Markus; Luger, Thomas; Luger, Ulrich; McArthur, Jane; Moser, Linda; Neuner, Julia; Orgel, Csilla; Ori, Gian Gabriele; Paternesi, Roberta; Peschier, Jarno; Pfeil, Isabella; Prock, Silvia; Radinger, Josef; Ramirez, Barbara; Ramo, Wissam; Rampey, Mike; Sams, Arnold; Sams, Elisabeth; Sandu, Oana; Sans, Alejandra; Sansone, Petra; Scheer, Daniela; Schildhammer, Daniel; Scornet, Quentin; Sejkora, Nina; Stadler, Andrea; Stummer, Florian; Taraba, Michael; Tlustos, Reinhard; Toferer, Ernst; Turetschek, Thomas; Winter, Egon; Zanella-Kux, Katja

    2014-05-01

    We report on the MARS2013 mission, a 4-week Mars analog field test in the northern Sahara. Nineteen experiments were conducted by a field crew in Morocco under simulated martian surface exploration conditions, supervised by a Mission Support Center in Innsbruck, Austria. A Remote Science Support team analyzed field data in near real time, providing planning input for the management of a complex system of field assets; two advanced space suit simulators, four robotic vehicles, an emergency shelter, and a stationary sensor platform in a realistic work flow were coordinated by a Flight Control Team. A dedicated flight planning group, external control centers for rover tele-operations, and a biomedical monitoring team supported the field operations. A 10 min satellite communication delay and other limitations pertinent to human planetary surface activities were introduced. The fields of research for the experiments were geology, human factors, astrobiology, robotics, tele-science, exploration, and operations research. This paper provides an overview of the geological context and environmental conditions of the test site and the mission architecture, in particular the communication infrastructure emulating the signal travel time between Earth and Mars. We report on the operational work flows and the experiments conducted, including a deployable shelter prototype for multiple-day extravehicular activities and contingency situations. PMID:24823799

  5. Indoor Radon Concentration Levels in Najran Region, Saudi Arabia

    SciTech Connect

    Alyami, S. H.; Al-Ghamdi, S. S.; Baig, M. R.; Al-Garawi, M.S.

    2010-07-07

    Measurement of indoor radon concentration was performed in Najran region in the south west of Saudi Arabia, using CR-39 dosimeter. Despite many previous studies on indoor radon concentrations in Saudi Arabia, the data available are still limited. The objective of this study, which is the first of its kind in the region, is to have preliminary data of radon in this region. Such measurement will contribute towards further studies in this region of Saudi Arabia. The indoor radon concentration was measured in the villages of Fara Al-Jabal and Badr Al-Janoob (about 2000 m above sea level), Hadadah and Al-Khanig (about 1700 m above sea level). It was found that radon distribution in these villages is normal skewed to the right, with a range of 9{+-}5 to 163{+-}32 Bqm{sup -3} and an average of 49{+-}2 Bqm{sup -3}. It was also found that the average radon concentration is independent of altitude. Our findings show that the values are below the safe limit of 150 Bqm{sup -3} set by the Environmental Protection Agency (EPA) of the USA

  6. Smartphone addiction among university students in Riyadh, Saudi Arabia

    PubMed Central

    Alosaimi, Fahad D.; Alyahya, Haifa; Alshahwan, Hatem; Mahyijari, Nawal Al; Shaik, Shaffi A.

    2016-01-01

    Objectives: To investigate the prevalence and correlates of smartphone addiction among university students in Saudi Arabia. Methods: This cross-sectional study was conducted in King Saud University, Riyadh, Kingdom of Saudi Arabia between September 2014 and March 2015. An electronic self administered questionnaire and the problematic use of mobile phones (PUMP) Scale were used. Results: Out of 2367 study subjects, 27.2% stated that they spent more than 8 hours per day using their smartphones. Seventy-five percent used at least 4 applications per day, primarily for social networking and watching news. As a consequence of using the smartphones, at least 43% had decrease sleeping hours, and experienced a lack of energy the next day, 30% had a more unhealthy lifestyle (ate more fast food, gained weight, and exercised less), and 25% reported that their academic achievement been adversely affected. There are statistically significant positive relationships among the 4 study variables, consequences of smartphone use (negative lifestyle, poor academic achievement), number of hours per day spent using smartphones, years of study, and number of applications used, and the outcome variable score on the PUMP. The mean values of the PUMP scale were 60.8 with a median of 60. Conclusion: University students in Saudi Arabia are at risk of addiction to smartphones; a phenomenon that is associated with negative effects on sleep, levels of energy, eating habits, weight, exercise, and academic performance. PMID:27279515

  7. New Seismicity Map for Central Part of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Bin Fayez, A. A.

    2007-05-01

    Riyadh city and central part of Saudi Arabia are located in the Arabian Plat which is known as a relativity stable platform. However, we have been able to determine some events that were caused by local faults. In addition, we have been able to record some regional Earthquakes that cussed by tectonic movements. Most of these local events are not felt. The Institute of Astronomy and Geophysics Research at King Abdulaziz City for Science and Technology installed nine earthquake portable stations in central part of Saudi Arabia around Riyadh city to record local and micro- seismicty events. We are using digital recorders (RefTek 72A) for data acquisition, and SAISAN, HYPOINVERSE software for analyses. Currently, I am using different types of velocity models, and I am developing a map that shows some micro-earthquake events for that region. In addition, it includes some regional events. The objective of this study is to define the active faults in central part of Saudi Arabia, and this study will not only yield additional information regarding the tectonic setting, but also revised hazard assessments for the region.

  8. Challenges in building health surveillance systems in saudi arabia.

    PubMed

    Al Saleem, Nouf; Househ, Mowafa; El Metwally, Ashraf

    2014-01-01

    This paper is aiming to briefly discuss the role of health surveillance system in strengthening public health at both the local and global level and the use of health informatics in effectively creating a database of health status for the population of Saudi Arabia. This review will specifically focus on the challenges that face the Kingdom of Saudi Arabia in order to effectively implement surveillance programs making use of advances in health information technology. Data collection was performed through a web-based retrieval of reports and articles and via an interview with an epidemiologist in the Saudi Ministry of Health Surveillance unit. Based on the results of this research, it was found that the use of technology has led to an improvement in communication between various stakeholders (e.g. clinicians, epidemiologists, and decision makers) by providing timely and accurate information needed for informed decision making. However, implementing an ideal model of surveillance systems in Saudi Arabia faces many challenges particularly in training healthcare providers to be qualified and competent enough to ensure the successful implementation of a disease surveillance system. PMID:25000066

  9. Mantle Flow beneath Arabia Offset from the Opening Red Sea

    NASA Astrophysics Data System (ADS)

    Stein, S. A.; Chang, S.; Merino, M.; van der Lee, S.; Stein, C. A.

    2010-12-01

    The rifting of continents involves a complex and poorly understood sequence of lithospheric stretching, volcanism, and mantle flow that eventually gives rise to seafloor spreading that forms a new ocean basin. The Red Sea, forming as the Arabian plate diverges from Africa, is a classic area for studying this process. Here, we present new insight from joint inversion of seismic wave travel times and waveforms to map velocity structure beneath Arabia and its surroundings. We find the low velocities expected for hot upwelling mantle material centered beneath the southern Red Sea and Gulf of Aden, consistent with the active spreading there. However, this hot material extends not below the northern Red Sea, but is instead offset to the east beneath Arabia, showing northward upper mantle flow from the Afar hotspot. The location of this low velocity channel beneath volcanic rocks erupted since rifting began 30 million years ago indicates that although the flow originates from the hotspot that is essentially fixed in the upper mantle, the channel moves with the Arabian plate. We thus propose that the absence of seafloor spreading in the northern Red Sea reflects the offset mantle flow. Because this offset has existed for millions of years, it is unclear whether it will evolve into seafloor spreading, rifting of Arabia above the channel, or both. This situation has aspects of the end-member models of rifting initiated by either mantle flow or lithospheric extension, and thus shows that the two can occur somewhat independently in different places before coalescing to seafloor spreading.

  10. Mars Telecommunications Orbiter, Artist's Concept

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This illustration depicts a concept for NASA's Mars Telecommunications Orbiter in flight around Mars. The orbiter is in development to be the first spacecraft with a primary function of providing communication links while orbiting a foreign planet. The project's plans call for launch in September 2009, arrival at Mars in August 2010 and a mission of six to 10 years while in orbit. Mars Telecommunication Orbiter would serve as the Mars hub for an interplanetery Internet, greatly increasing the information payoff from other future Mars missions. The mission is designed to orbit Mars more than 10 times farther from the planet than orbiters dedicated primarily to science. The high-orbit design minimizes the time that Mars itself blocks the orbiter from communicating with Earth and maximizes the time that the orbiter is above the horizon -- thus capable of communications relay -- for rovers and stationary landers on Mars' surface.

  11. Mars - Pathway to the stars

    NASA Astrophysics Data System (ADS)

    Angelo, J. A., Jr.; Buden, D.

    Mars has and will continue to play a key role in our exploration and conquest of the Solar System. Within the context of the creation of humanity's extraterrestrial civilization, the major technical features of the following Mars programs are reviewed: the Mars Geoscience/Climatology Orbiter; the Mars Aeronomy Orbiter; the Mars airplane; the Mars Penetrator Network; Mars surface rovers and mobility systems; human exploration of Mars; and permanent Martian bases and settlements. Mars properly explored and utilized opens the way to the resources of the asteroid belt and the outer planets; supports the creation of smart machines for space exploration and exploitation; and encourages the creation of autonomous niches of intelligent life within heliocentric space. All of these developments, in turn, establish the technological pathway for the first interstellar missions.

  12. Examining Mars with SPICE

    NASA Technical Reports Server (NTRS)

    Acton, Charles H.; Bachman, Nathaniel J.; Bytof, Jeff A.; Semenov, Boris V.; Taber, William; Turner, F. Scott; Wright, Edward D.

    1999-01-01

    The International Mars Conference highlights the wealth of scientific data now and soon to be acquired from an international armada of Mars-bound robotic spacecraft. Underlying the planning and interpretation of these scientific observations around and upon Mars are ancillary data and associated software needed to deal with trajectories or locations, instrument pointing, timing and Mars cartographic models. The NASA planetary community has adopted the SPICE system of ancillary data standards and allied tools to fill the need for consistent, reliable access to these basic data and a near limitless range of derived parameters. After substantial rapid growth in its formative years, the SPICE system continues to evolve today to meet new needs and improve ease of use. Adaptations to handle landers and rovers were prototyped on the Mars pathfinder mission and will next be used on Mars '01-'05. Incorporation of new methods to readily handle non-inertial reference frames has vastly extended the capability and simplified many computations. A translation of the SPICE Toolkit software suite to the C language has just been announced. To further support cartographic calculations associated with Mars exploration the SPICE developers at JPL have recently been asked by NASA to work with cartographers to develop standards and allied software for storing and accessing control net and shape model data sets; these will be highly integrated with existing SPICE components. NASA specifically supports the widest possible utilization of SPICE capabilities throughout the international space science community. With NASA backing the Russian Space Agency and Russian Academy of Science adopted the SPICE standards for the Mars 96 mission. The SPICE ephemeris component will shortly become the international standard for agencies using the Deep Space Network. U.S. and European scientists hope that ESA will employ SPICE standards on the Mars Express mission. SPICE is an open set of standards, and

  13. Deucalionis Regio, Mars: Evidence for a unique mineralogic endmember and a crusted surface

    NASA Astrophysics Data System (ADS)

    Merenyi, E.; Edgett, K. S.; Singer, R. B.

    1993-03-01

    A small equatorial region south of Sinus Meridiani, Deucalionis Regio, has been found spectrally distinct from other regions as seen in a high spectral resolution telescopic image of the meridian hemisphere of Mars. Analysis of Viking IRTM and other related data suggest that Deucalionis Regio has a crusted surface. The crust-bonding minerals may contribute to the spectral uniqueness of this region. Two independent analyses of spectral images, linear spectral mixing and supervised classification based on the spectral shapes, showed that in addition to the well-known spectral endmember regions in this image (western Arabia, south Acidalia, and Sinus Meridiani), Deucalionis Regio has spectral properties that are unique enough to make it a principle endmember unit. In those earlier works, Deucalionis Regio was referred to as 'Meridiani Border.' Analysis of thermal inertia, rock abundance, and albedo information derived from Viking images and Infrared Thermal Mapper (IRTM) data obtained 1977-80 also indicate that Deucalionis Regio has a surface of distinctly different physical properties when compared to Arabia, Sinus Meridiani, and Acidalia. Deucalionis Regio has a thermal inertia equivalent to the Martian average, a low rock abundance (less than 5 percent), and an intermediate albedo and color. Considerable effort by previous investigators has revealed a consistent model for the surface (upper few cm) properties of the endmember reigons Arabia, Sinus Meridiani, and Acidalia. Compared with these regions, we consider that Deucalionis Regio is not a region of either (1) unconsolidated, fine bright dust like Arabia, (2) considerable windblown unconsolidated sand like Sinus Meridiani, or (3) a rocky-and-sandy surface like Acidalia. Thus, we are forced to consider that either the surface of Deucalionis Regio is made of unconsolidated fine to medium sand (about 250 microns) of an unusual and previously unreported color and albedo, or that the surface is crusted, fine

  14. Electronic crosstalk characterization of Terra MODIS long wave infrared channels

    NASA Astrophysics Data System (ADS)

    Madhavan, Sriharsha; Xiong, Xiaoxiong; Sun, Junqiang; Chiang, Kwofu; Wu, Aisheng

    2015-09-01

    Terra (T) MODerate-resolution Imaging Spectroradiometer (MODIS), a heritage Earth observing sensor has completed 15 years of operation as of December 18 2014. T-MODIS has 36 spectral channels designed to monitor the land, ocean, and atmosphere. The long term climate data record from T-MODIS is an important dataset for global change monitoring. Sixteen of the spectral channels fall in the Mid (M) (3.7-4.5μm) to Long (L) (6.7-14.1μm)Wave InfraRed (M/LWIR) wavelengths, which are also referred to as the Thermal Emissive Bands (TEBs). To date the TEBs have very satisfactory performance which is attributed to the scan-by-scan calibration using an on-board BlackBody whose temperature is traceable to the NIST temperature standards. However, with an aging instrument, it was observed from 2010 onwards that the Photo Voltaic LWIR channels (Bands 27-30) have suffered significantly from electronic crosstalk. This is mainly due to the deterioration of the electronic circuits of the relevant bands in the LWIR Focal Plane Array (FPA). In this paper, we report the characterization of the electronic crosstalk in the above-mentioned bands using the well characterized test site such as Dome Concordia (C). Such characterization can be used to reduce the effects of crosstalk when implemented in the future Level 1B reprocessing and thereby increasing the radiometric fidelity of the concerned bands.

  15. Atmospheric correction for the ASTER visible data on Terra satellite

    NASA Astrophysics Data System (ADS)

    Takashima, T.; Masuda, K.; Sano, I.; Mukai, S.

    2001-01-01

    An atmospheric correction algorithm over the heterogeneous surface on the emergent radiation from the top of the atmosphere is proposed. This is an atmospheric correction code for the ASTER visible channels on Terra satellite, which have a spatial resolution of 15m. Therefore, interactions of atmospheric radiation with radiation reflected by the heterogeneous surface should be accounted for in this atmospheric correction. The surface is simulated by a checkerboard type terrain composed of land or ocean pixels. To investigate the contribution of adjacent pixels, two additional parameters based on the diffuse transmission(α) and reflection(β) function of the atmosphere are introduced. These parameters are independent of the surface reflection properties and thus may be used for any surface. The present method was developed with reference to existing numerical results based on one-dimensional radiative transfer code. Furthermore, as vicarious calibration, skylight polarization measurements were taken by a spectro-polarimeter over the Nevada desert. The measurements indicate little absorption by aerosols in the atmosphere at wavelengths from 550nm to 700nm. Furthermore the aerosols could not be spherical particles in a poly-dispersion.

  16. Multispectral Cloud Retrievals from MODIS on Terra and Aqua

    NASA Technical Reports Server (NTRS)

    King, Michael D.; Platnick, Steven; Ackerman, Steven A.; Menzel, W. Paul; Gray, Mark A.; Moody, Eric G.

    2002-01-01

    The Moderate Resolution Imaging Spectroradiometer (MODIS) was developed by NASA and launched onboard the Terra spacecraft on December 18, 1999 and the Aqua spacecraft on April 26, 2002. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from each polar-orbiting, sun-synchronous, platform at an altitude of 705 km, and provides images in 36 spectral bands between 0.415 and 14.235 microns with spatial resolutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). In this paper we will describe the various methods being used for the remote sensing of cloud properties using MODIS data, focusing primarily on the MODIS cloud mask used to distinguish clouds, clear sky, heavy aerosol, and shadows on the ground, and on the remote sensing of cloud optical properties, especially cloud optical thickness and effective radius of water drops and ice crystals. Additional properties of clouds derived from multispectral thermal infrared measurements, especially cloud top pressure and emissivity, will also be described. Results will be presented of MODIS cloud properties both over the land and over the ocean, showing the consistency in cloud retrievals over various ecosystems used in the retrievals. The implications of this new observing system on global analysis of the Earth's environment will be discussed.

  17. Terra and Aqua: new data for epidemiology and public health

    PubMed Central

    Tatem, Andrew J.; Goetz, Scott J.; Hay, Simon I.

    2012-01-01

    Earth-observing satellites have only recently been exploited for the measurement of environmental variables of relevance to epidemiology and public health. Such work has relied on sensors with spatial, spectral and geometric constraints that have allowed large-area questions associated with the epidemiology of vector-borne diseases to be addressed. Moving from pretty maps to pragmatic control tools requires a suite of satellite-derived environmental data of higher fidelity, spatial resolution, spectral depth and at similar temporal resolutions to existing meteorological satellites. Information derived from sensors onboard the next generation of moderate-resolution Earth-observing sensors may provide the key. The MODIS and ASTER sensors onboard the Terra and Aqua platforms provide substantial improvements in spatial resolution, number of spectral channels, choices of bandwidths, radiometric calibration and a much-enhanced set of pre-processed and freely available products. These sensors provide an important advance in moderate-resolution remote sensing and the data available to those concerned with improving public health. PMID:22545030

  18. Estimating terra MODIS polarization effect using ocean data

    NASA Astrophysics Data System (ADS)

    Wald, Andrew; Brinkmann, Jake; Wu, Aisheng; Xiong, Jack

    2016-05-01

    Terra MODIS has been known since pre-launch to have polarization sensitivity, particularly in shortest-wavelength bands 8 and 9. On-orbit reflectance trending of pseudo-invariant sites show a variation in reflectance as a function of band and scan mirror angle of incidence consistent with time-dependent polarization effects from the rotating doublesided scan mirror. The MODIS Characterization Support Team [MCST] estimates the Mueller matrix trending from this variation as observed from a single desert site, but this effect is not included in Collection 6 [C6] calibration. Here we extend the MCST's current polarization sensitivity monitoring to two ocean sites distributed over latitude to help estimate the uncertainties in the derived Mueller matrix. The Mueller matrix elements derived for polarization-sensitive Band 8 for a given site are found to be fairly insensitive to surface brdf modeling. The site-to-site variation is a measure of the uncertainty in the Mueller estimation. Results for band 8 show that the polarization correction reduces mirror-side striping by up to 50% and reduces the instrument polarization effect on reflectance time series of an ocean target.

  19. Geology of Terra Nova oil field, Grand Banks, Newfoundland

    SciTech Connect

    Dwyer, J.D.; Sullivan, G.W.; Park, J.

    1986-05-01

    Oil was discovered at the Petro-Canada et al Terra Nova K-08 well in May 1984. The well was drilled in the Jeanne d'Arc subbasin, 340 km east of St. John's, Newfoundland, and 35 km southeast of the giant Hibernia oil field. Follow-up wells provided log correlations and core data that have been used with a three-dimensional seismic survey to construct a geologic model. Mapping the field demonstrated a combination structural-stratigraphic trap. The reservoir is within the lower part of the Jeanne d'Arc sequence (Upper Jurassic). This conglomeratic sandstone is interpreted as having been deposited in a nearshore to fluvial setting by basinward, northward progradation of fan-delta systems. The reservoir has a depositional limit updip to the south, and is overstepped and sealed by transgressive shales of the upper Jeanne d'Arc. Oil source is from the underlying Egret (Oxfordian-Kimmeridgian) argillaceous limestones. The geologic model and seismic interpretation have been tested by appraisal drilling.

  20. Vicarious calibration of Terra ASTER, MISR, and MODIS

    NASA Astrophysics Data System (ADS)

    Thome, Kurtis J.; Biggar, Stuart F.; Choi, Hyun J.

    2004-10-01

    The Advanced Spaceborne Thermal Emission and Reflection and Radiometer (ASTER), Multi-angle Imaging Spectroradiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) are all onboard the Terra platform. An important aspect of the use of MODIS, and other Earth Science Enterprise sensors, has been the characterization and calibration of the sensors and validation of their data products. The Remote Sensing Group at the University of Arizona has been active in this area through the use of ground-based test sites. This paper presents the results from the reflectance-base approach using the Railroad Valley Playa test site in Nevada for ASTER, MISR, and MODIS and thus effectively a cross-calibration between all three sensors. The key to the approach is the measurement of surface reflectance over a 1-km2 area of the playa and results from this method shows agreement with MODIS to better than 5%. The paper examines biases between ASTER and the other two sensors in the VNIR due to uncertainties in the onboard calibrator for ASTER and in the SWIR due to an optical crosstalk effect.