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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.

  3. 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

  4. 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.

  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. 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.

  7. 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.

  8. 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.

  9. 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

  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. The role of groundwater in the origin of the indurated layered deposits of Arabia Terra, Mars

    NASA Astrophysics Data System (ADS)

    Andrews-Hanna, J. C.; Wiseman, S. M.; Arvidson, R. E.

    2008-12-01

    Indurated layered deposits of likely sedimentary origin are widely distributed across the Arabia Terra region of Mars. In situ observations by the MER Opportunity rover of one such deposit in Meridiani Planum have been interpreted to represent grains composed of dirty evaporites that have been extensively reworked by fluvial and aeolian processes in a playa environment and diagenetically modified by a fluctuating water table. Stratigraphic relationships, morphological similarities, and spectral evidence suggest a related origin for the many layered deposits throughout Arabia Terra. Isolated intra-crater deposits, erosional outliers, and pedestal craters suggest that the Arabia Terra deposits were once thicker and more widespread than their current extent. We investigate the origin of these sedimentary deposits using global and regional hydrological models, in which groundwater flow is driven by evaporation where the water table intersects the surface and redistribution of that water as low-latitude precipitation. These models predict focused groundwater upwelling and evaporation in Arabia Terra during the Late Noachian to Early Hesperian, driven by its unique topography relative to the adjacent southern highlands and northern lowlands. This hydrological cycle would have brought a steady flux of groundwater to the surface, which upon evaporation, would concentrate any dissolved solutes as a cementing salt that would indurate aeolian material and allow buildup of thick sedimentary deposits. Groundwater upwelling would first be limited to the large craters in the region, resulting in rapid sedimentary infilling by a combination of evaporites and evaporite-cemented clastic material. As the craters were filled, groundwater upwelling would spread out over broad regions of Arabia Terra, producing widespread deposits covering much of the inter-crater plains. The observed distribution and thickness of the deposits agrees with the predictions from the hydrological models

  13. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2011-10-01

    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.

  15. 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.

  16. 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

  17. 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.

  18. 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

  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. Implications for the Daily Variation and the Low Value of Thermal Inertia at Arabia Terra on Mars

    NASA Astrophysics Data System (ADS)

    Toyota, T.; Saruya, T.; Kurita, K.

    2010-12-01

    Active nature of the Martian surface is considered to be responsible for various styles of the atmosphere-surface interaction. Here, we propose an idea to interpret the daily variation and the low value of thermal inertia at Arabia Terra on Mars. Thermal inertia calculated with the surface temperature obtained by remote sensing exhibits daily variation and seasonal variation. Putzig and Mellon [1] suggested that horizontal or vertical heterogeneity may yield apparent thermal inertia which varies with time of day and season. However, their interpretation couldn’t completely explain the extent and the phase of the temporal variation of thermal inertia at Arabia Terra. We would like to propose another possibility to explain the characteristics of the thermal inertia at Arabia Terra. In addition, the value of thermal inertia is extremely low at Arabia Terra. Daytime thermal inertia at Arabia Terra is as low as 20 tiu [1,2], which is lower than the value of thermal inertia of 1 micron dust aggregates ( 61 tiu [3]). To explain these characteristics of Arabia Terra, we proposed an idea that condensation and sublimation of water ice at the granular surface cause the daily variation and the low value of the thermal inertia at Arabia Terra. At nighttime, water vapor condenses at the surface. Immediately after sunrise, water ice at the surface sublimates. Electric force and sublimating gas pressure could affect the porosity of the surface. We suppose that the daily variation of the thermal inertia is caused by presence of deposition/removal of water ice and the low value of the thermal inertia is caused by the higher value of the bulk porosity than random close packing. To substantiate the above model, there remain four main questions to be answered. 1) Is there sufficient water vapor at the atmosphere above Arabia Terra?, 2) Does the sufficient amount of water condense at the surface during the night?, 3) Can water vapor and other factors make the surface porosity higher

  5. Geologic map transecting the highland/lowland boundary zone, Arabia Terra, Mars; quadrangles 30332, 35332, 40332, and 45332

    USGS Publications Warehouse

    McGill, George E.

    2002-01-01

    Arabia Terra is a large region of cratered terrane extending from about 20° W. longitude eastward across the prime meridian to about 300° W. longitude for an average east-west width of about 5,000 km. The northern boundary ranges from 40° N. to 45° N.; the southern boundary is a poorly defined zone at about 0° N. Thus, the north-south width is about 2,500 km. Except for the westernmost part, Arabia Terra has an albedo higher than surrounding terranes. The four quadrangles mapped (30332, 35332, 40332, 45332) provide a north-south strip from highland terrane in the south to lowland terrane in the north. The northern portion of Arabia Terra is the type region for both fretted terrane and fretted valleys and, along with the immediately adjacent northern plains, is also the site of some of the best examples of putative flow deposits present as aprons around isolated knobs and mesas or as deposits on the floors of fretted valleys and on the lowland surface. Mass wasting, eolian erosion or deposition, glacial scouring, fluvial or shoreline erosion, deposition from an ocean, hydrovolcanism, plateau volcanism, and faulting have all been proposed to account for the topography and crater characteristics in northern Arabia Terra. Although underlain by what appears to be typical highland terrane, Arabia Terra is anomalously low, with elevations generally below the planetary reference. Probably the most important question concerning the global-scale tectonic history of Mars is the origin of the crustal dichotomy. The northern lowland is not only several kilometers lower than the southern highland, it also is surfaced by materials that are significantly younger than surface materials in the southern highland. The young surface materials in the lowland rest unconformably on basement material having an age comparable to the exposed ancient highland terrane to the south. The age of the dichotomy continues to be controversial, as does the mechanism for its formation, as reviewed

  6. 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.

  7. 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.

  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. 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).

  10. 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

  11. 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.

  12. 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

  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. 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.

  3. 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.

  4. Mars Express OMEGA Observations over Terra Meridiani

    NASA Technical Reports Server (NTRS)

    Arvidson, R. E.; Poulet, F.; Bibring, J.-P.; Wolff, M.; Gendrin, A.; Morris, R. V.; Freeman, J. J.; Bellucci, G.

    2005-01-01

    The OMEGA hyperspectral imager (0.35 to 5.08 micrometers) covered the hematite-bearing plains and underlying etched terrains of Terra Meridiani during several orbits with spatial resolutions ranging from several hundred meters to approximately 2 km. We extracted and analyzed surface reflectance spectra from OMEGA data for the approximately 864,000 square kilometers surrounding the Opportunity site. In this paper we focus on analysis of OMEGA orbit 485 data for the plains and etched terrains located to the northeast of the Opportunity landing site.

  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. Atlantis basin, Sirenum Terrae, Mars: geological setting and astrobiological implications

    NASA Astrophysics Data System (ADS)

    de Pablo, Miguel A.; Fairén, Alberto G.

    2004-07-01

    The accomplishment of detailed geomorphological studies is a prerequisite for the location of regions in which the prevailing conditions in the past, or at present, may allow the development of possible life forms. The Atlantis basin, located in Sirenum Terrae, Southern hemisphere of Mars, is one of these astrobiologically interesting regions, where the existence of geological features such as ancient volcanic edifices, sedimentary deposits of an ancient lake and recent gullies seem to indicate the long-term presence of a thermal source and a water reservoir deep and stable enough to sustain biological processes. Here we describe the most relevant topographic and geomorphologic features in the region, highlighting the possibility for liquid water to have been present in the basin and outskirts in different moments of Mars' history. We also apply this analysis to an initial discussion of the influence of the hydrogeological evolution of the region in the putative development and/or survival of life forms in Atlantis basin.

  9. Crater in Arabia

    NASA Technical Reports Server (NTRS)

    2004-01-01

    28 October 2004 This high resolution Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small meteor impact crater with bouldery ejecta in the Arabia Terra region of Mars. The image is located near 11.9oN, 342.2oW. The 300 meter scale bar is about 328 yards long. Sunlight illuminates the scene from the upper left.

  10. Cold-Climate Geomorphology of Tempe Terra, Mars

    NASA Astrophysics Data System (ADS)

    van Gasselt, Stephan; Hauber, Ernst; Rossi, Angelo-Pio; Dumke, Alexander; Neukum, Gerhard

    2010-05-01

    The fretted terrain at the Martian dichotomy boundary hosts an abundance of landforms related to the creep of mountain debris and ice which have become known as so-called lobate debris aprons and units of lineated valley fills and concentric crater fills. Although such features are related to different morphologic settings, there is a general consensus that these features are in principle genetically connected to the process of ice-assisted creep. We here investigate lobate debris aprons in the Tempe Terra/Mareotis Fossae region of Mars on the basis of high resolution imagery and topographic data and focus on the emplacement and degradational history and on a mantling deposit which indicates the past and/or present existence of near surface ice. According to our observations we propose a multi-stage model for landscape evolution in the Tempe Terra region, which needs further verification in other areas of the dichotomy boundary. We have currently no observational basis for assumptions on the formation of remnant massifs in the near-escarpment region of the highland-lowland boundary which means that all we can say about the emplacement and distribution of remnant massifs is that they are either autochthonous, i.e., erosional remnants of highland material or uplifted crustal material as suggested for the southern hemispheric circum-Hellas and Argyre Planitiae remnants. Remnants have undergone erosional processes, be it by fluvial erosion, or be it by gravitational processes, such as landsliding and mass wasting as well as deflation and denudation. Additionally, cyclic obliquity changes as proposed for Mars and cyclic loss and redeposition of volatiles and dust produced a record of ice-poor and ice-rich landforms, respectively, that subsequently intermixed through degradational processes where the ice/dust-rich mantling deposit either covered the remnant completely or was remobilized gravitationally by downslope movement and revealed the underlying topography. Apron

  11. 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

  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. Hydraulic Inferences for Mars From Geologic Mapping in Margaritifer Terra, Mars and Measurements of Terrestrial Analogs.

    NASA Astrophysics Data System (ADS)

    Fortezzo, C. M.; Williams, K. K.; Springer, A. E.

    2006-12-01

    Past hydrogeologic models of Mars have focused primarily on exploring a link between large scale groundwater systems and the Martian outflow channels. These groundwater models have generally given only slight consideration to the occurrence of smaller-scale valley network that dissect much of the southern highlands. Ongoing geologic and geomorphic mapping in 6 Mars Transverse Mercator 1:500K quadrangles (17.5ºS - 27.5ºS and 345ºE - 360ºE) in southeast Margaritifer Terra, Mars, shows valley networks are often associated with the internal and external slopes of the impact basin but are absent on the basin floor. We propose a sequence of ponding in the basin followed by infiltration into the subsurface, transmission down the regional slope and sapping valleys forming on the crater flanks. The Martian valley morphologies are analogous with morphologies of terrestrial spring-fed sapping processes (i.e., amphitheater-shaped heads, stubby tributaries, steep walls, and U-shaped valleys that maintain consistent width-depth ratios along their length). Flow measurements from spring-fed channels in the Navajo Sandstone near Escalante, Utah supply data from areas actively forming sapping valleys and provide insight into the interaction between surface-water and groundwater. Measurements taken during pre-monsoon and post-snow melt run-off and planned post- monsoonal measurements will provide a range of discharge values furnishing data to model the interaction of subsurface- and surface-water flow on Mars. Published stratigraphic models of Mars postulate that the upper kilometer of material is ejecta related well-mixed unsorted debris ranging from meter sized blocks down to dust sized particles overlying fractured bedrock. Detailed mapping using high resolution datasets allows for accurate characterization of surficial material properties on a local scale which will help to better understand influences on hydrologic variables (i.e. permeability, hydraulic conductivity, etc

  16. 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.

  17. 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.

  18. Geologic Map of the MTM-20272 and-25272 Quadrangles, Tyrrhena Terra Region of Mars

    USGS Publications Warehouse

    Mest, Scott C.; Crown, David A.

    2006-01-01

    Introduction Mars Transverse Mercator (MTM) -20272 and -25272 quadrangles (lat 17.5?-27.5? S., long 270?-275? W.) cover part of the highlands of Tyrrhena Terra north of Hellas Planitia. The surface of the Tyrrhena Terra region records a complex history of impact cratering and modification by fluvial and eolian activity. The map area consists primarily of intercrater plains, impact crater material, and crater floor material. An extensive valley network, Vichada Valles, as well as several smaller networks, dissects the northern part of the map area. The abundance and widespread nature of fluvial features within the map area have significant implications for past Martian environmental conditions. The degraded terrains surrounding Hellas Planitia provide constraints on the role and timing of volatile-driven activity in the evolution of the highlands. The geologic history of this area may have been influenced not only by the presence of Hellas Planitia but also by other buried impact basins.

  19. Implications for hydrologic processes on Mars from extensive bedrock outcrops throughout Terra Meridiani.

    PubMed

    Hynek, Brian M

    2004-09-01

    Grey haematite was recently detected in the Terra Meridiani region of Mars by the Thermal Emission Spectrometer onboard the Mars Global Surveyor spacecraft. The formation of haematite on Earth often requires liquid water to be present for long periods of time, making this an important target for deciphering the history of water on Mars. The Mars Exploration Rover Opportunity landed in Meridiani early in 2004 and has since discovered light-toned bedrock outcrops rich in chemical and textural signatures of long-term water interaction locally at the landing site. Here I use remote sensing data to show that the light-toned outcrops at the landing site are not a local phenomenon. Instead, they are observable throughout the haematite-bearing plains in both visible and thermal infrared remote sensing data. Moreover, the light-toned material outcrops around much of the margin and is mappable for hundreds of kilometres to the north, east and west of the plains. I infer that 3 x 10(5) km(2) of this material is exposed over 20 degrees of longitude, indicating the extended presence of surface or near-surface water over a large region of Mars.

  20. A cold-wet middle-latitude environment on Mars during the Hesperian-Amazonian transition: Evidence from northern Arabia valleys and paleolakes

    NASA Astrophysics Data System (ADS)

    Wilson, Sharon A.; Howard, Alan D.; Moore, Jeffrey M.; Grant, John A.

    2016-09-01

    The growing inventory of post-Noachian fluvial valleys may represent a late, widespread episode of aqueous activity on Mars, contrary to the paradigm that fluvial activity largely ceased around the Noachian-Hesperian boundary. Fresh shallow valleys (FSVs) are widespread from ~30 to 45° in both hemispheres with a high concentration in northern Arabia Terra. Valleys in northern Arabia Terra characteristically start abruptly on steeper slopes and terminate in topographic depressions at elevations corresponding to model-predicted lake levels. Longer valley systems flowed into and out of chains of paleolakes. Minimum discharges based on the dimensions of the incised channel assuming medium to coarse sand-size grains ranges from tens to hundreds of m3 s-1, respectively, consistent with formation via snowmelt from surface or sub-ice flows. Hydrologic calculations indicate the valleys likely formed in hundreds of years or less, and crater statistics constrain the timing of fluvial activity to between the Hesperian and middle Amazonian. Several craters with channels extending radially outward supports evidence for overflow of interior crater lakes possibly fed by groundwater. Most FSVs occur away from young impact craters which make an association with impact processes improbable. The widespread occurrence of FSVs along with their similar morphology and shared modest state of degradation is consistent with most forming during a global interval of favorable climate, perhaps contemporaneous with alluvial fan formation in equatorial and midlatitudes. Evidence for a snowmelt-based hydrology and considerable depths of water on the landscape in Arabia supports a cold, wet, and possibly habitable environment late in Martian history.

  1. Possible karst landforms in two unnamed craters in Tyrrhena Terra, Mars

    NASA Astrophysics Data System (ADS)

    Baioni, Davide; Tramontana, Mario

    2016-11-01

    Tyrrhena Terra, an area in the cratered highlands south of the Martian equator, contains two unnamed craters. The mineralogical composition of light-toned deposits (LTDs) within these craters is unknown. We performed morphologic and morphometric analyses of the surfaces of these LTDs through an integrated study of images available through the Reconnaissance Mars Orbiter High-Resolution Imaging Science Experiment. Our analysis revealed that the Martian landforms contain dolines of polygenetic origin. These dolines are similar to karst landforms observed in different karst terrains on Earth and other regions on Mars. The observed karst landforms might highlight the possible evaporitic origin of these materials, suggesting a climatic change and the presence of liquid water caused by ice melting during the Amazonian age.

  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. 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

  4. Amazonian-aged fluvial system and associated ice-related features in Terra Cimmeria, Mars

    NASA Astrophysics Data System (ADS)

    Adeli, Solmaz; Hauber, Ernst; Kleinhans, Maarten; Le Deit, Laetitia; Platz, Thomas; Fawdon, Peter; Jaumann, Ralf

    2016-10-01

    The Martian climate throughout the Amazonian is widely believed to have been cold and hyper-arid, very similar to the current conditions. However, ubiquitous evidence of aqueous and glacial activity has been recently reported, including channels that can be tens to hundreds of kilometres long, alluvial and fluvial deposits, ice-rich mantles, and glacial and periglacial landforms. Here we study a ∼340 km-long fluvial system located in the Terra Cimmeria region, in the southern mid-latitudes of Mars. The fluvial system is composed of an upstream catchment system with narrow glaciofluvial valleys and remnants of ice-rich deposits. We observe depositional features including fan-shaped deposits, and erosional features such as scour marks and streamlined islands. At the downstream section of this fluvial system is an outflow channel named Kārūn Valles, which displays a unique braided alluvial fan and terminates on the floor of the Ariadnes Colles basin. Our observations point to surface runoff of ice/snow melt as the water source for this fluvial activity. According to our crater size-frequency distribution analysis the entire fluvial system formed during early to middle Amazonian, between ∼ 1.8-0.2+0.2 Ga to 510-40+40 Ma. Hydraulic modelling indicates that the Kārūn Valles and consequently the alluvial fan formation took place in geologically short-term event(s). We conclude that liquid water was present in Terra Cimmeria during the early to middle Amazonian, and that Mars during that time may have undergone several episodic glacial-related events.

  5. 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.

  6. Extensive phyllosilicate-bearing layer identified in northwestern Noachis Terra, Mars

    NASA Astrophysics Data System (ADS)

    Buczkowski, D.; Seelos, K. D.; Murchie, S. L.; Seelos, F. P.; Malaret, E.; Hash, C.

    2009-12-01

    Noachis Terra is a highland cratered plain on Mars, extending from 20°S to 80°S latitude and 55°W to 30°E longitude. Evidence for a widespread phyllosilicate-bearing layer has been identified in a distinct region in northwest Noachis Terra, bound by Coprates and Eos Chasma to the north, Thaumasia Planum to the west and the Argyre basin to the south. Uzboi Vallis, a major Martian valley system, cuts through Noachis Terra and is the eastern boundary of our region of interest. In northwest Argyre a laterally extensive phyllosilicate-bearing deposit has been identified directly below a thin cap-rock. A layer of similar composition has been identified in the walls of eastern Coprates Chasma, although at significantly greater depth. It has been suggested that these outcrops represent the same material unit. If so, then the same phyllosilicate-bearing layer should be observable in the walls of valley systems and craters in the intervening Noachis Terra region, increasing with depth towards the north. Two small valley systems incise NW Noachis: Her Desher Vallis and Nirgal Vallis. Nirgal Vallis is a tributary of Uzboi Vallis, joining the larger system to the south of Holden crater. Her Desher Vallis is an isolated valley that does not seem to connect to any craters or larger valleys. CRISM multispectral mapping observations (mosaicked at ~230 m/pixel) indicate that a phyllosilicate-bearing layer is exposed along the length of both valley systems and in the interior rims of many craters in the region. Phyllosilicates have been positively identified in 20-40 m/pixel resolution CRISM hyperspectral targeted observations of the walls of Her Desher Valles and Nirgal Vallis; as indicated by the mapping data, there is a distinct phyllosilicate-bearing layer located only a few meters below the surface volcanics and extending laterally along the walls. A similar phyllosilicate-bearing layer is also identified running laterally in the interior walls of some nearby craters

  7. Geologic map of MTM -15027, -20027, -25027, and -25032 quadrangles, Margaritifer Terra region of Mars

    USGS Publications Warehouse

    Irwin, Rossman P.; Grant, John A.

    2013-01-01

    Mars Transverse Mercator (MTM) quadrangles −15027, −20027, −25027, and −25032 (lat 12.5°−28° S., long 330°−335° E. and lat 22.5°−28° S., long 324.5°−330° E.) in southwestern Margaritifer Terra include diverse erosional landforms, sedimentary deposits, and tectonic structures that record a long geologic and geomorphic history. The northeastern regional slope of the pre-Noachian crustal dichotomy (as expressed along the Chryse trough) and structures of the informally named Middle Noachian or older Holden and Ladon impact basins dominate the topography of the map area. A series of mesoscale outflow channels, Uzboi, Ladon, and Morava Valles, integrated these formerly enclosed basins by overflow and incision around the Noachian/Hesperian transition, although some flooding may have occurred earlier. The area includes excellent examples of Late Noachian to Hesperian valley networks, dissected crater rims, alluvial fans, deltas, and light-toned layered deposits, particularly in Holden and Eberswalde craters. Structural forms include Tharsis-radial grabens, Hesperian wrinkle ridges, floor-fractured impact craters, and severely disrupted chaotic terrains. These well-preserved landforms and sedimentary deposits represent multiple erosional epochs and discrete flooding events, which provide significant insight into the geomorphic processes and climate change on early Mars.

  8. 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.

  9. 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.

  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. 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

  12. A possible synoptic source of water for alluvial fan formation in southern Margaritifer Terra, Mars

    NASA Astrophysics Data System (ADS)

    Grant, John A.; Wilson, Sharon A.

    2012-11-01

    The morphometry and occurrence of crater-bound fans in southern Margaritifer Terra that were active from around the Hesperian-Amazonian boundary into the Early Amazonian is consistent with emplacement related to synoptic precipitation. Precipitation, possibly occurring as snow, may have been locally influenced by topography and (or) orbital variations. It is not known how much of the total sediment inventory in the fans relates to this late activity versus possible earlier events where water may have been available from alternate sources such as impact-related melting of ground ice. Winds may have concentrated late occurring precipitation into existing relief and (or) preexisting alcoves that facilitated physical weathering to produce fine sediments later incorporated into fans. Two of the craters containing fan deposits, Holden and Eberswalde, were finalists for the MSL landing site. Results suggest that exposed and accessible fan sediments at both crater sites may record a late period of colder, drier conditions relative to early Mars that was punctuated by ephemeral water-driven activity.

  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. 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.

  18. 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.

  19. 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

  20. 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.

  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. Using Remote Sensing Techniques to Assess the Geologic Context of Olivine-Bearing Materials within Terra Sirenum, Mars

    NASA Astrophysics Data System (ADS)

    Anderson, M.; Osterloo, M. M.

    2015-12-01

    Understanding olivine-bearing materials in Terra Sirenum provides insight into the magmatic and hydrologic processes that shaped the Southern Highlands of Mars. Our study addresses two questions: "What is the geologic context of olivine compositions in the study area?" and "What does olivine abundance, composition, and geologic context suggest about the magmatic and weathering processes in our study area?" To answer these questions, we mapped olivine deposits within a region of Terra Sirenum using JMARS [1]. We used Thermal Emission Imaging System (THEMIS) data to map the extent of olivine deposits and to understand their degree of consolidation. To investigate olivine composition, we used the Thermal Emission Spectrometer (TES) global maps of Forsterite/Fayalite compositions [2]. We found that the olivine compositions vary from most iron-rich types (Fo01) to the most magnesium-rich (Fo91), with the vast majority identified as Fo68. The results of our study are consistent with those implied by the magma overturn model [3], which explains the compositional changes in Martian magmas over time. In addition, the extent of olivine-bearing deposits within our study area suggests that mechanical weathering (e.g., aeolian and gravity-driven processes) is more likely to dominate the sedimentary record in recent geologic time over water-driven processes. We will present our results, which detail the present-day surface geology of our study area in Terra Sirenum. Our results have implications for Martian magma evolution as well as the extent water has played in shaping the surface of the planet. [1] Gorelick, N., et al. (2003), Lunar and Planetary Science, XXXIV. [2] Koeppen, W.C., et al. (2008), Journal of Geophysical Research, 113, E002984. [3] Elkins-Tanton, L.T., et al. (2003), Meteorites & Planetary Science, 38, tb00013.

  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. 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.

  7. 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

  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. 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.

  10. Synoptic snowfall as a possible source of water for late alluvial fan activity in southern Margaritifer Terra, Mars

    NASA Astrophysics Data System (ADS)

    Grant, J. A.; Wilson, S. A.

    2012-12-01

    Alluvial deposits on Mars provide an important record of the environmental conditions enabling their formation. A recent study of alluvial fans within large craters in southern Margaritifer Terra showed that deposition of exposed surfaces occurred late in Martian history, within the latest Hesperian or well into the early Amazonian. These fans typically display well developed alcoves and fan surfaces preserve distributary channels standing ~10-15 m in relief (via inversion of topography). Understanding whether the water responsible for fan emplacement was related to a local source (e.g., impact-related melting of ground ice) versus regional or global synoptic climatic events has implications for the nature of late water activity and potential habitability of Mars. Water released during and after impact events may be sufficient to cause runoff within and around newly formed craters and could contribute to late valley and fan formation without requiring changes in climate. For example, the impact forming the Amazonian-aged Hale crater (35.7S, 323.6E) produced valleys, but was not likely responsible for the alluvial fans because 1) alluvial fans occur in craters up to 700-800 km away from Hale; 2) craters with fans occur at a range of azimuths from Hale (and may not be consistent with downwind transport of volatiles under prevailing winds); and 3) many craters bearing older floor deposits and mantling deposits are closer to Hale than those containing fans. The impact forming the Hesperian-aged Holden crater (26.1S, 326E) is another possible local source of water, but like Hale, craters hosting fans occur at a range of azimuths and up to hundreds of km away from Holden. Moreover, at least six degraded craters on the relatively high relief rim of Holden suggest a gap in time between the Holden impact and the fluvial modification of these near-rim craters and the simultaneous fan activity within Holden. Fans within Holden also record evidence for multiple periods of

  11. 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.

  12. 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

  13. 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).

  14. 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.

  15. 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

  16. Testing Multivariate Adaptive Regression Splines (MARS) as a Method of Land Cover Classification of TERRA-ASTER Satellite Images.

    PubMed

    Quirós, Elia; Felicísimo, Angel M; Cuartero, Aurora

    2009-01-01

    This work proposes a new method to classify multi-spectral satellite images based on multivariate adaptive regression splines (MARS) and compares this classification system with the more common parallelepiped and maximum likelihood (ML) methods. We apply the classification methods to the land cover classification of a test zone located in southwestern Spain. The basis of the MARS method and its associated procedures are explained in detail, and the area under the ROC curve (AUC) is compared for the three methods. The results show that the MARS method provides better results than the parallelepiped method in all cases, and it provides better results than the maximum likelihood method in 13 cases out of 17. These results demonstrate that the MARS method can be used in isolation or in combination with other methods to improve the accuracy of soil cover classification. The improvement is statistically significant according to the Wilcoxon signed rank test. PMID:22291550

  17. 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.

  18. 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.

  19. Mars

    NASA Technical Reports Server (NTRS)

    Kieffer, Hugh H. (Editor); Jakosky, Bruce M. (Editor); Snyder, Conway W. (Editor); Matthews, Mildred S. (Editor)

    1992-01-01

    The present volume on Mars discusses visual, photographic and polarimetric telescopic observations, spacecraft exploration of Mars, the origin and thermal evolution of Mars, and the bulk composition, mineralogy, and internal structure of the planet. Attention is given to Martian gravity and topography, stress and tectonics on Mars, long-term orbital and spin dynamics of Mars, and Martian geodesy and cartography. Topics addressed include the physical volcanology of Mars, the canyon system on planet, Martian channels and valley networks, and ice in the Martian regolith. Also discussed are Martian aeolian processes, sediments, and features, polar deposits of Mars, dynamics of the Martian atmosphere, and the seasonal behavior of water on Mars.

  20. Internal structure and early thermal evolution of Mars from Mars Global Surveyor topography and gravity.

    PubMed

    Zuber, M T; Solomon, S C; Phillips, R J; Smith, D E; Tyler, G L; Aharonson, O; Balmino, G; Banerdt, W B; Head, J W; Johnson, C L; Lemoine, F G; McGovern, P J; Neumann, G A; Rowlands, D D; Zhong, S

    2000-03-10

    Topography and gravity measured by the Mars Global Surveyor have enabled determination of the global crust and upper mantle structure of Mars. The planet displays two distinct crustal zones that do not correlate globally with the geologic dichotomy: a region of crust that thins progressively from south to north and encompasses much of the southern highlands and Tharsis province and a region of approximately uniform crustal thickness that includes the northern lowlands and Arabia Terra. The strength of the lithosphere beneath the ancient southern highlands suggests that the northern hemisphere was a locus of high heat flow early in martian history. The thickness of the elastic lithosphere increases with time of loading in the northern plains and Tharsis. The northern lowlands contain structures interpreted as large buried channels that are consistent with northward transport of water and sediment to the lowlands before the end of northern hemisphere resurfacing. PMID:10710301

  1. Winds drive dune movement on Mars

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-01-01

    Sand dunes, a common feature on the surface of Mars, can provide a record of recent and past changes. Some dunes near Mars's polar areas have recently been observed to change due to carbon dioxide ice sublimation, but it has not been confirmed whether dunes are still active all over Mars. Winds contribute to dune movement on Earth, but wind tunnel and atmospheric computer simulations have suggested that strong winds would be rare in the current Martian atmosphere. In a new study, Silvestro et al. observe recent dune movement in Mars's tropical regions, which are not affected by seasonal changes in carbon dioxide frost. Focusing on the Arabia Terra and Meridiani regions on Mars, the researchers analyzed images from the High Resolution Science Experiment (HiRISE) camera on board the Mars Reconnaissance Orbiter as well as other sources of data. They measured migration rates of two groups of ripples in the sand in a dune field in Meridiani Planum and found that dunes advanced about 0.4-1 meter in a Martian year.

  2. 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.

  3. 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.

  4. 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.

  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. 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

  7. Age of the Mars Global Northerly Slope: Evidence From Utopia Planitia

    NASA Technical Reports Server (NTRS)

    McGill, George E.

    2002-01-01

    Recent results from the Mars Orbiter Laser Altimeter (MOLA) experiment on Mars Global Surveyor (MGS) indicate that most of Mars is characterized by a very gentle, roughly northerly slope. Detailed mapping in north-central Arabia Terra combined with superposition relations and crater counts indicate that, in that region at least, this northerly slope must have been formed no later than Late Hesperian, with the most likely time of formation being Late Hesperian. Current research in Utopia Planitia intended as a test of extant models for the formation of giant polygons has turned up good evidence for a Late Hesperian age for the northerly tilt in this region as well, as will be discussed.

  8. 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.

  9. Mars

    NASA Astrophysics Data System (ADS)

    McSween, H. Y., Jr.; McLennan, S. M.

    Of all the planets, Mars is the most Earthlike, inviting geochemical comparisons. Geochemical data for Mars are derived from spacecraft remote sensing, surface measurements and Martian meteorites. These analyses of exposed crustal materials enable estimates of bulk planet composition and inferences about its iron-rich mantle and core, as well as constraints on planetary differentiation and crust-mantle evolution. Mars probably had an early magma ocean, but there is no evidence for plate tectonics or crustal recycling any time in its history. The crust is basaltic in composition and lithologically heterogeneous, with radiometric crystallization ages ranging from ~4 billion years to within the last several hundred million years. Mantle sources for magmas vary considerably in incompatible element abundances. Although Mars is volatile element-rich, estimations of the amount of water delivered to the surface by volcanism are controversial. Low-temperature aqueous alteration affected the ancient Martian surface, producing clay minerals, sulfates, and other secondary minerals. Weathering and diagenetic trends are distinct from terrestrial chemical alteration, indicating different aqueous conditions. Organic matter has been found in Martian meteorites, but no geochemical signal of life has yet been discovered. Dynamic geochemical cycles for some volatile elements are revealed by stable isotope measurements. Long-term secular changes in chemical and mineralogical compositions of igneous rocks and sediments have been documented but are not well understood.

  10. Mars

    NASA Astrophysics Data System (ADS)

    Spohn, Tilman; Sohl, Frank; Breuer, Doris

    Mars is the fourth planet out from the sun. It is a terrestrial planet with a density suggesting a composition roughly similar to that of the Earth. Its orbital period is 687 days, its orbital eccentricity is 0.093 and its rotational period is about 24 hours. Mars has two small moons of asteroidal shapes and sizes (about 11 and 6 km mean radius), the bigger of which, Phobos, orbits with decreasing semimajor orbit axis. The decrease of the orbit is caused by the dissipation of tidal energy in the Martian mantle. The other satellite, Deimos, orbits close to the synchronous position where the rotation period of a planet equals the orbital period of its satellite and has hardly evolved with time. Mars has a tenous atmosphere composed mostly of CO2 with strong winds and with large scale aeolian transport of surface material during dust storms and in sublimation-condensation cycles between the polar caps. The planet has a small magnetic field, probably not generated by dynamo action in the core but possibly due to remnant magnetization of crustal rock acquired earlier from a stronger magnetic field generated by a now dead core dynamo. A dynamo powered by thermal power alone would have ceased a few billions of years ago as the core cooled to an extent that it became stably stratified. Mars' topography and its gravity field are dominated by the Tharsis bulge, a huge dome of volcanic origin. Tharsis was the major center of volcanic activity, a second center is Elysium about 100° in longitude away. The Tharsis bulge is a major contributor to the non-hydrostaticity of the planet's figure. The moment of inertia factor together with the mass and the radius presently is the most useful constraint for geophysical models of the Martian interior. It has recently been determined by Doppler range measurements to the Mars Pathfinder Lander to be 0.3662 +/- 0.0017 (Folkner et al. 1997). In addition, models of the interior structure use the chemistry of the SNC meteorites which are

  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. Ancient geodynamics and global-scale hydrology on Mars.

    PubMed

    Phillips, R J; Zuber, M T; Solomon, S C; Golombek, M P; Jakosky, B M; Banerdt, W B; Smith, D E; Williams, R M; Hynek, B M; Aharonson, O; Hauck, S A

    2001-03-30

    Loading of the lithosphere of Mars by the Tharsis rise explains much of the global shape and long-wavelength gravity field of the planet, including a ring of negative gravity anomalies and a topographic trough around Tharsis, as well as gravity anomaly and topographic highs centered in Arabia Terra and extending northward toward Utopia. The Tharsis-induced trough and antipodal high were largely in place by the end of the Noachian Epoch and exerted control on the location and orientation of valley networks. The release of carbon dioxide and water accompanying the emplacement of approximately 3 x 10(8) cubic kilometers of Tharsis magmas may have sustained a warmer climate than at present, enabling the formation of ancient valley networks and fluvial landscape denudation in and adjacent to the large-scale trough.

  13. 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.

  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. 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.; 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.

  16. 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.

  17. 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/

  18. 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

  19. Quasi-periodic bedding in the sedimentary rock record of Mars.

    PubMed

    Lewis, Kevin W; Aharonson, Oded; Grotzinger, John P; Kirk, Randolph L; McEwen, Alfred S; Suer, Terry-Ann

    2008-12-01

    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 approximately 10 meters thick, and one site contains hundreds of meters of strata bundled into larger units at a approximately 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.

  20. 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.

  1. 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.

  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. Terra Harvest software architecture

    NASA Astrophysics Data System (ADS)

    Humeniuk, Dave; Klawon, Kevin

    2012-06-01

    Under the Terra Harvest Program, the DIA has the objective of developing a universal Controller for the Unattended Ground Sensor (UGS) community. The mission is to define, implement, and thoroughly document an open architecture that universally supports UGS missions, integrating disparate systems, peripherals, etc. The Controller's inherent interoperability with numerous systems enables the integration of both legacy and future UGS System (UGSS) components, while the design's open architecture supports rapid third-party development to ensure operational readiness. The successful accomplishment of these objectives by the program's Phase 3b contractors is demonstrated via integration of the companies' respective plug-'n'-play contributions that include controllers, various peripherals, such as sensors, cameras, etc., and their associated software drivers. In order to independently validate the Terra Harvest architecture, L-3 Nova Engineering, along with its partner, the University of Dayton Research Institute, is developing the Terra Harvest Open Source Environment (THOSE), a Java Virtual Machine (JVM) running on an embedded Linux Operating System. The Use Cases on which the software is developed support the full range of UGS operational scenarios such as remote sensor triggering, image capture, and data exfiltration. The Team is additionally developing an ARM microprocessor-based evaluation platform that is both energy-efficient and operationally flexible. The paper describes the overall THOSE architecture, as well as the design decisions for some of the key software components. Development process for THOSE is discussed as well.

  4. 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

  5. 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

  6. EOS Terra Terra Constellation Exit/Future Maneuver Plans Update

    NASA Technical Reports Server (NTRS)

    Mantziaras, Dimitrios

    2016-01-01

    This EOS Terra Constellation Exit/Future Maneuver Plans Update presentation will discuss brief history of Terra EOM work; lifetime fuel estimates; baseline vs. proposed plan origin; resultant exit orbit; baseline vs. proposed exit plan; long term orbit altitude; revised lifetime proposal and fallback options.

  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. Investigating the Cause of Moving Albedo Boundaries in the Oxia Palus Region of Mars

    NASA Astrophysics Data System (ADS)

    Mukherjee, P.; Geissler, P. E.

    2010-12-01

    Recent imagery from the MARCI camera on Mars Reconnaissance Orbiter (MRO) in addition to previous analyses of Mars Global Surveyor MOC data reveals a variety of large scale changes in the appearance of the Martian surface (Geissler and Mukherjee, this meeting). The MOC and MARCI data revealed a surprising range of behavior in various regions of Mars. Our area of focus is a region featuring such albedo changes in Oxia Palus in western Arabia Terra. The albedo boundary between dark and bright terrain at western Oxia Palus moved 26 km eastwards between a MOC mosaic from September 2005 and a MARCI mosaic from July 2009. The goal of this project is to understand what is causing this albedo boundary to move. A distinctive feature of the Oxia Palus albedo boundary is a narrow (~25 km wide) fringe of locally high albedo that shifts as the boundary advances from the dark region (Acidalia) towards the bright terrain (Oxia). High resolution images from MRO’s CTX and HiRISE cameras will be used to test the hypothesis that the high albedo fringe is a coating of bright dust that is stripped by the winds from the advancing dark terrain and deposited ahead of the moving boundary.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. TERRA and the state of the telomere.

    PubMed

    Rippe, Karsten; Luke, Brian

    2015-11-01

    Long noncoding telomeric repeat-containing RNA (TERRA) has been implicated in telomere maintenance in a telomerase-dependent and a telomerase-independent manner during replicative senescence and cancer. TERRA's proposed activities are diverse, thus making it difficult to pinpoint the critical roles that TERRA may have. We propose that TERRA orchestrates different activities at chromosome ends in a manner that depends on the state of the telomere.

  16. 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

  17. 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.

  18. 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.

  19. Mars Global Surveyor Approach Image

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image is the first view of Mars taken by the Mars Global Surveyor Orbiter Camera (MOC). It was acquired the afternoon of July 2, 1997 when the MGS spacecraft was 17.2 million kilometers (10.7 million miles) and 72 days from encounter. At this distance, the MOC's resolution is about 64 km per picture element, and the 6800 km (4200 mile) diameter planet is 105 pixels across. The observation was designed to show the Mars Pathfinder landing site at 19.4 N, 33.1 W approximately 48 hours prior to landing. The image shows the north polar cap of Mars at the top of the image, the dark feature Acidalia Planitia in the center with the brighter Chryse plain immediately beneath it, and the highland areas along the Martian equator including the canyons of the Valles Marineris (which are bright in this image owing to atmospheric dust). The dark features Terra Meridiani and Terra Sabaea can be seen at the 4 o`clock position, and the south polar hood (atmospheric fog and hazes) can be seen at the bottom of the image. Launched on November 7, 1996, Mars Global Surveyor will enter Mars orbit on Thursday, September 11 shortly after 6:00 PM PDT. After Mars Orbit Insertion, the spacecraft will use atmospheric drag to reduce the size of its orbit, achieving a circular orbit only 400 km (248 mi) above the surface in early March 1998, when mapping operations will begin.

    The Mars Global Surveyor is operated by the Mars Surveyor Operations Project managed for NASA by the Jet Propulsion Laboratory, Pasadena CA. The Mars Orbiter Camera is a duplicate of one of the six instruments originally developed for the Mars Observer mission. It was built and is operated under contract to JPL by an industry/university team led by Malin Space Science Systems, San Diego, CA.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. Day And Night In Terra Meridiani

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 11 June 2004 This pair of images shows part of the Terra Meridiani region.

    Day/Night Infrared Pairs

    The image pairs presented focus on a single surface feature as seen in both the daytime and nighttime by the infrared THEMIS camera. The nighttime image (right) has been rotated 180 degrees to place north at the top.

    Infrared image interpretation

    Daytime: Infrared images taken during the daytime exhibit both the morphological and thermophysical properties of the surface of Mars. Morphologic details are visible due to the effect of sun-facing slopes receiving more energy than antisun-facing slopes. This creates a warm (bright) slope and cool (dark) slope appearance that mimics the light and shadows of a visible wavelength image. Thermophysical properties are seen in that dust heats up more quickly than rocks. Thus dusty areas are bright and rocky areas are dark.

    Nighttime: Infrared images taken during the nighttime exhibit only the thermophysical properties of the surface of Mars. The effect of sun-facing versus non-sun-facing energy dissipates quickly at night. Thermophysical effects dominate as different surfaces cool at different rates through the nighttime hours. Rocks cool slowly, and are therefore relatively bright at night (remember that rocks are dark during the day). Dust and other fine grained materials cool very quickly and are dark in nighttime infrared images.

    Image information: IR instrument. Latitude 1.3, Longitude 0.5 East (359.5 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

  8. Breaking new ground: digging into TERRA function.

    PubMed

    Maicher, André; Lockhart, Arianna; Luke, Brian

    2014-05-01

    Despite the fact that telomeres carry chromatin marks typically associated with silent heterochromatin, they are actively transcribed into TElomeric Repeat containing RNA (TERRA). TERRA transcription is conserved from yeast to man, initiates in the subtelomeric region and proceeds through the telomeric tract of presumably each individual telomere. TERRA levels are increased in yeast survivors and in cancer cells employing ALT as a telomere maintenance mechanism (TMM). Thus, TERRA may be a promising biomarker and potential target in anti-cancer therapy. Interestingly, several recent publications implicate TERRA in regulatory processes including telomere end protection and the establishment of the heterochromatic state at telomeres. A picture is emerging whereby TERRA acts as a regulator of telomere length and hence the associated onset of replicative senescence in a cell. In this review we will summarize the latest results regarding TERRA transcription, localization and related function. A special focus will be set on the potential role of TERRA in the regulation of telomere length and replicative senescence. Possible implications of increased TERRA levels in yeast survivors and in ALT cancer cells will be discussed.

  9. 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.

  10. 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.

  11. Tabanidae (Diptera) of Saudi Arabia

    PubMed Central

    Al Dhafer, H.M.; Dawah, H.A.; Abdullah, M.A.

    2009-01-01

    Samples were collected from southern, central and eastern regions of Saudi Arabia using Malaise traps and sweep nets. Nine species of Tabanidae were identified, two for the first time from Saudi Arabia, Hybomitra peculiaris (Szilády) and Atylotus pulchellus (Loew). Therefore, the total number of Tabanidae in Saudi Arabia is 31 species. Remarks of the species recorded in this study were given. A key to the genera of Tabanidae occurring in the Arabian Peninsula is also provided. Available literature for Saudi Arabian Tabanidae is summarized and provided. It is concluded that the tabanid fauna of Saudi Arabia is more similar to that of the Palaearctic region than to the Afrotropical region. PMID:23961046

  12. 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.

  13. Telomere elongation chooses TERRA ALTernatives.

    PubMed

    Arora, Rajika; Azzalin, Claus M

    2015-01-01

    Alternative Lengthening of Telomeres (ALT) mechanisms allow telomerase-negative immortal cells to buffer replicative telomere shortening. ALT is naturally active in a number of human cancers and might be selected upon telomerase inactivation. ALT is thought to operate through homologous recombination (HR) occurring between telomeric repeats from independent chromosome ends. Indeed, suppression of a number of HR factors impairs ALT cell proliferation. Yet, how HR is initiated at ALT telomeres remains elusive. Mounting evidence suggests that the long noncoding telomeric RNA TERRA renders ALT telomeres recombinogenic by forming RNA:DNA hybrids with the telomeric C-rich strand. TERRA and telomeric hybrids act in concert with a number of other factors, including the RNA endoribonuclease RNaseH1 and the single stranded DNA binding protein RPA. The functional interaction network built upon these different players seems indispensable for ALT telomere maintenance, and digging into the molecular details of this previously unappreciated network might open the way to novel avenues for cancer treatments.

  14. Telomere functions grounding on TERRA firma.

    PubMed

    Azzalin, Claus M; Lingner, Joachim

    2015-01-01

    Long noncoding telomeric repeat-containing RNAs - TERRAs - are transcribed in a regulated manner from telomeres throughout eukaryotes. TERRA molecules consist of chromosome end-specific subtelomeric sequences and telomeric repeats at their 3' ends. Recent work suggests that TERRA sustains several important functions at chromosome ends. TERRA can regulate telomere length through modulation of exonuclease 1 and telomerase, it may promote recruitment of chromatin modifiers to damaged telomeres and thereby enable DNA end-processing, and it may promote telomere protein composition changes during cell cycle progression. Furthermore, telomere transcription regulates chromosome-end mobility within the nucleus. We review how TERRA, by regulated expression and by providing a molecular scaffold for various protein enzymes, can support a large variety of vital functions.

  15. Outflow channel sources, reactivation, and chaos formation, Xanthe Terra, Mars

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Sasaki, S.; Kuzmin, R.O.; Dohm, J.M.; Tanaka, K.L.; Miyamoto, H.; Kurita, K.; Komatsu, G.; Fairen, A.G.; Ferris, J.C.

    2005-01-01

    The undulating, warped, and densely fractured surfaces of highland regions east of Valles Marineris (located north of the eastern Aureum Chaos, east of the Hydraotes Chaos, and south of the Hydaspis Chaos) resulted from extensional surface warping related to ground subsidence, caused when pressurized water confined in subterranean caverns was released to the surface. Water emanations formed crater lakes and resulted in channeling episodes involved in the excavation of Ares, Tiu, and Simud Valles of the eastern part of the circum-Chryse outflow channel system. Progressive surface subsidence and associated reduction of the subsurface cavernous volume, and/or episodes of magmatic-driven activity, led to increases of the hydrostatic pressure, resulting in reactivation of both catastrophic and non-catastrophic outflow activity. Ancient cratered highland and basin materials that underwent large-scale subsidence grade into densely fractured terrains. Collapse of rock materials in these regions resulted in the formation of chaotic terrains, which occur in and near the headwaters of the eastern circum-Chryse outflow channels. The deepest chaotic terrain in the Hydaspis Chaos region resulted from the collapse of pre-existing outflow channel floors. The release of volatiles and related collapse may have included water emanations not necessarily linked to catastrophic outflow. Basal warming related to dike intrusions, thermokarst activity involving wet sediments and/or dissected ice-enriched country rock, permafrost exposed to the atmosphere by extensional tectonism and channel incision, and/or the injection of water into porous floor material, may have enhanced outflow channel floor instability and subsequent collapse. In addition to the possible genetic linkage to outflow channel development dating back to at least the Late Noachian, clear disruption of impact craters with pristine ejecta blankets and rims, as well as preservation of fine tectonic fabrics, suggest that plateau subsidence and chaos formation may have continued well into the Amazonian Period. The geologic and paleohydrologic histories presented here have important implications, as new mechanisms for outflow channel formation and other fluvial activity are described, and new reactivation mechanisms are proposed for the origin of chaotic terrain as contributors to flooding. Detailed geomorphic analysis indicates that subterranean caverns may have been exposed during chaos formation, and thus chaotic terrains mark prime locations for future geologic, hydrologic, and possible astrobiologic exploration. ?? 2004 Elsevier Inc. All rights reserved.

  16. 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

  17. 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

  18. ES4 Terra-Xtrk Ed3

    Atmospheric Science Data Center

    2016-10-12

    ... Temporal Resolution:  Monthly, Daily, Monthly Hourly File Format:  HDF Tools:  ... for Terra and Aqua; Edition2 for TRMM) are approved for science publications.  Additional Info:  b SCAR-B ...

  19. EOS Terra: Mission Status Constellation MOWG

    NASA Technical Reports Server (NTRS)

    Mantziaras, Dimitrios

    2016-01-01

    This EOS Terra Mission Status Constellation MOWG will discuss mission summary; spacecraft subsystems summary, recent and planned activities; inclination adjust maneuvers, conjunction history, propellant usage and lifetime estimate; and end of mission plan.

  20. Mapping of statistical characteristics of topography on Mars with MOLA data

    NASA Astrophysics Data System (ADS)

    Kreslavsky, M. A.; Head, J. W.

    2003-04-01

    Mars Orbiter Laser Altimeter (MOLA) produced a huge set of precise measurements of Mars surface elevation with uniform 0.3 km spacing along tracks. We use this data set to study statistical characteristics of the martian topography at the scale from hundreds meters to tens of kilometers. Here we give a summary of our published and new results on mapping of statistical characteristics of topography for the purposes of geomorphology and understanding of surface formation and alteration processes. The interquartile widths of the differential-slope- or curvature-frequency distributions are used as measures of the surface roughness at a series of scales. The Hurst exponent quantifies the scale dependence of roughness. The normalized median curvature characterizes the prevalence of concave or convex topography. The normalized median differential slope being a measure of the asymmetry of the slope-frequency distribution, characterizes the north - south slope asymmetry. All maps clearly show the latitudinal trend. High-latitude areas (from the polar deposits edges to 60 deg latitude) are characterized by lower subkilometer-scale roughness, higher Hurst exponent and stronger prevalence of concave topography than the equatorial zone (within 30 deg). The transitional zones (from 30 to 60 deg) are characterized by transitional values of roughness and Hurst exponent, by prevalence of convex topography, and by noticeable slope asymmetry: the equator-facing slopes are steeper. The roughness and Hurst exponent also shows obvious correlation with geological units. The maps shows also some anomalous regions related to distribution of specific surficial deposits. For example, convex topography prevails for giant polygons; eastern part of Daedalia Planum has anomalous prevalence of concave topography and strong slope asymmetry; south-eastern part of Arabia Terra has slope asymmetry and prevalence of convex topography; the hematite deposit has an anomalous signature in all maps.

  1. 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)

  2. 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…

  3. 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

  4. 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

  5. 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.

  6. Wet Mars, Dry Mars

    NASA Astrophysics Data System (ADS)

    Fillingim, M. O.; Brain, D. A.; Peticolas, L. M.; Yan, D.; Fricke, K. W.; Thrall, L.

    2012-12-01

    The magnetic fields of the large terrestrial planets, Venus, Earth, and Mars, are all vastly different from each other. These differences can tell us a lot about the interior structure, interior history, and even give us clues to the atmospheric history of these planets. This poster highlights the third in a series of presentations that target school-age audiences with the overall goal of helping the audience visualize planetary magnetic field and understand how they can impact the climatic evolution of a planet. Our first presentation, "Goldilocks and the Three Planets," targeted to elementary school age audiences, focuses on the differences in the atmospheres of Venus, Earth, and Mars and the causes of the differences. The second presentation, "Lost on Mars (and Venus)," geared toward a middle school age audience, highlights the differences in the magnetic fields of these planets and what we can learn from these differences. Finally, in the third presentation, "Wet Mars, Dry Mars," targeted to high school age audiences and the focus of this poster, the emphasis is on the long term climatic affects of the presence or absence of a magnetic field using the contrasts between Earth and Mars. These presentations are given using visually engaging spherical displays in conjunction with hands-on activities and scientifically accurate 3D models of planetary magnetic fields. We will summarize the content of our presentations, discuss our lessons learned from evaluations, and show (pictures of) our hands-on activities and 3D models.

  7. Wet Mars, Dry Mars

    NASA Astrophysics Data System (ADS)

    Fillingim, Matthew; Brain, D.; Peticolas, L.; Yan, D.; Fricke, K.; Thrall, L.

    2012-10-01

    The magnetic fields of the large terrestrial planets, Venus, Earth, and Mars, are all vastly different from each other. These differences can tell us a lot about the interior structure, interior history, and even give us clues to the atmospheric history of these planets. This poster highlights the third in a series of presentations that target school-age audiences with the overall goal of helping the audience visualize planetary magnetic field and understand how they can impact the climatic evolution of a planet. Our first presentation, "Goldilocks and the Three Planets," targeted to elementary school age audiences, focuses on the differences in the atmospheres of Venus, Earth, and Mars and the causes of the differences. The second presentation, "Lost on Mars (and Venus)," geared toward a middle school age audience, highlights the differences in the magnetic fields of these planets and what we can learn from these differences. Finally, in the third presentation, "Wet Mars, Dry Mars," targeted to high school age audiences and the focus of this poster, the emphasis is on the long term climatic affects of the presence or absence of a magnetic field using the contrasts between Earth and Mars. These presentations are given using visually engaging spherical displays in conjunction with hands-on activities and scientifically accurate 3D models of planetary magnetic fields. We will summarize the content of our presentations, discuss our "lessons learned" from formative evaluation, and show (pictures of) our hands-on activities and 3D models.

  8. 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 ...

  9. 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.

  10. 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.

  11. Two geologic systems providing terrestrial analogues for the exploration of sulfate deposits on Mars: Initial spectral characterization

    NASA Astrophysics Data System (ADS)

    Sgavetti, M.; Pompilio, L.; Roveri, M.; Manzi, V.; Valentino, G. M.; Lugli, S.; Carli, C.; Amici, S.; Marchese, F.; Lacava, T.

    2009-05-01

    We present the Messinian evaporite suite (Mediterranean region) and the Solfatara hydrothermal system (Phlegraean Fields volcanic province, Italy), discuss their implications for understanding the origin of sulfates on Mars and show preliminary sets of VNIR laboratory and in situ reflectance spectra of rocks from these geologic systems. The choice was based on a number of evidence relative to Mars: (1) the chemistry of the Martian sulfates, suggesting fluid interactions with possibly alkali-basaltic rocks and/or regolith; (2) close range evidence of sulfates within sedimentary formations on Mars; (3) sulfate spectral signatures associated to large-scale layered patterns interpreted as thick depositional systems on Mars. The Messinian evaporites comprise three units: primary shallow-water sulfates (primary lower gypsum: PLG), shallow- to deep-water mixed sulfates and clastic terrigenous deposits (resedimented lower gypsum: RLG), and shallow-water associations of primary sulfates and clastic fluvio-deltaic deposits (upper evaporites: UE). The onset of the Messinian evaporites records the transition to negative hydrologic budget conditions associated with the Messinian Salinity Crisis, which affected the entire Mediterranean basin and lasted about 640 kyr. The Solfatara is a still evolving hydrothermal system that provides epithermal deposits precipitated from the interaction of fluids and trachybasaltic to phonolitic rocks. Thermal waters include alkali-chloride, alkali-carbonate and alkali-sulfate endmembers. The wide spectrum of sedimentary gypsum facies within the Messinian formation includes some of the depositional environments hitherto identified on Mars and others not found on Mars. The PLG unit includes facies associations correlated over long distances, that could be a possible analog of the stratified rock units exposed from Arabia Terra at least as far as Valles Marineris. The facies cycles within the UE unit can be compared to the sequences of strata

  12. TERRA: Building New Communities for Advanced Biofuels

    ScienceCinema

    Cornelius, Joe; Mockler, Todd; Tuinstra, Mitch

    2016-07-12

    ARPA-E’s Transportation Energy Resources from Renewable Agriculture (TERRA) program is bringing together top experts from different disciplines – agriculture, robotics and data analytics – to rethink the production of advanced biofuel crops. ARPA-E Program Director Dr. Joe Cornelius discusses the TERRA program and explains how ARPA-E’s model enables multidisciplinary collaboration among diverse communities. The video focuses on two TERRA projects—Donald Danforth Center and Purdue University—that are developing and integrating cutting-edge remote sensing platforms, complex data analytics tools and plant breeding technologies to tackle the challenge of sustainably increasing biofuel stocks.

  13. 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

  14. 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

  15. Terra Nova breaks new ground for alliances

    SciTech Connect

    Ghiselin, D.

    1996-08-01

    This paper reviews the development of alliances to help develop the Terra Nova oil and gas field in the offshore Atlantic areas of Canada. Largely attributed to BP, the strategic alliance concept got its start in the North Sea and on the North Slope of Alaska. BP saw it as the best way to take advantage of economy-of-scale, mitigate risk, and achieve outsourcing goals while retaining their core competencies. This paper reviews the methods of developing the alliances, the developing of a development plan for the Terra Nova field, and how the alliance plans to maximize the profittability of the operation for all involved.

  16. Radar Observations of Recent Mars Landing Sites

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    The Mars Exploration Rovers Spirit and Opportunity will arrive at their respective landing sites of Gusev Crater and Terra Meridiani in January 2004. During the 2001 and 2003 Mars Oppositions both landing sites were targeted for a series of radar observations using the telescopes of the Goldstone Deep Space Communications Complex (GDSCC). This paper will present results of terrestrial delay- Doppler radar observations of the landing sites, predictions for the surface properties that will be encountered, and, after successful landings, correlation between the predicted and observed surface properties. The in-situ observations made by both missions serve as ground truth for the validation of the high resolution radar mapping results.

  17. 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.

  18. Searching for Pedogenic Phyllosilicates in Ancient Soils on Mars

    NASA Astrophysics Data System (ADS)

    Horgan, B.; Christensen, P. R.; Bell, J. F.

    2011-12-01

    On Earth, vast deposits rich in phyllosilicates are commonly created during soil formation, or pedogenesis. When soils are preserved in the stratigraphic record as paleosols, they become valuable resources for terrestrial geologists because paleosol isotopes, mineralogy, and chemical weathering profiles can be used to reconstruct ancient surface environments and to provide quantitative constraints on regional paleo-climate. Thus, paleosol sequences developed in sedimentary settings can record millions of years of surface and climatic evolution. Ancient paleosols on Earth also have excellent organic and biosignature preservation potential, and therefore harbor some of the oldest known (2-3 Ga) non-marine organics, biosignatures, and fossils. On Mars, pedogenesis in the ancient past may be responsible for some of the phyllosilicate-bearing units observed today, especially for regionally extensive deposits and those in clear sedimentary settings (e.g., Arabia Terra/Mawrth Vallis, Gale Crater, Noctis Labyrinthus). Many of these possibly pedogenic deposits exhibit compositional layering (e.g., interbedded kaolinites, smectites, and sulfates), which may have formed due to episodic sediment deposition under changing environmental conditions. Such deposits represent excellent targets for in situ investigation, as finding and characterizing paleosols on Mars would allow us to place constraints on the extent and duration of past surface and near-surface habitability, and may even provide preserved samples of ancient martian organics. We are currently investigating a broad range of methods for identifying and characterizing paleosols on Mars from orbit and in situ with Mars Science Laboratory, based on analysis of phyllosilicate-rich (30-95 wt.%) Eocene-Oligocene paleosols in the Painted Hills of the John Day Fossil Beds National Monument in Eastern Oregon. These paleosols were formed under a wide range of environmental conditions, and include highly weathered soils rich in

  19. 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

  20. 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.

  1. Complete Genome Sequence of Gordonia terrae 3612

    PubMed Central

    Russell, Daniel A.; Guerrero Bustamante, Carlos A.; Garlena, Rebecca A.

    2016-01-01

    Here, we report the complete genome sequence of Gordonia terrae 3612, also known by the strain designations ATCC 25594, NRRL B-16283, and NBRC 100016. The genome sequence reveals it to be free of prophage and clustered regularly interspaced short palindromic repeats (CRISPRs), and it is an effective host for the isolation and characterization of Gordonia bacteriophages. PMID:27688316

  2. Terra--A School's Venture into Interdependence.

    ERIC Educational Resources Information Center

    Tashjian, Michi; And Others

    1979-01-01

    To create a feeling of school unity and to reinforce the concept of human interdependence, the teachers of Friends' Central School planned Project Terra, a six-week school-wide activity. With the school viewed as a mythical planet, classes designed their own cultures and interacted as nations. (SJL)

  3. Complete Genome Sequence of Gordonia terrae 3612.

    PubMed

    Russell, Daniel A; Guerrero Bustamante, Carlos A; Garlena, Rebecca A; Hatfull, Graham F

    2016-01-01

    Here, we report the complete genome sequence of Gordonia terrae 3612, also known by the strain designations ATCC 25594, NRRL B-16283, and NBRC 100016. The genome sequence reveals it to be free of prophage and clustered regularly interspaced short palindromic repeats (CRISPRs), and it is an effective host for the isolation and characterization of Gordonia bacteriophages. PMID:27688316

  4. 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.

  5. 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

  6. 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...

  7. 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

  8. Mars Pathfinder

    NASA Technical Reports Server (NTRS)

    Dubov, D.

    1995-01-01

    Mars Pathfinder, launching in December 1996 and landing on Mars on July 4, 1997, will demonstrate a low-cost delivery system to the surface of Mars for follow-on landers. Objectives are the return of engineering data, panoramic images of the Martian surface, microrover experiments, etc. A technical mission description is included.

  9. 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.

  10. 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.

  11. 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.

  12. 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).

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Antimicrobial resistance in Saudi Arabia

    PubMed Central

    Zowawi, Hosam M.

    2016-01-01

    Antimicrobial resistance (AMR) is increasingly being highlighted as an urgent public and animal health issue worldwide. This issue is well demonstrated in bacteria that are resistant to last-line antibiotics, suggesting a future with untreatable infections. International agencies have suggested combating strategies against AMR. Saudi Arabia has several challenges that can stimulate the emergence and spread of multidrug-resistant bacteria. Tackling these challenges need efforts from multiple sectors to successfully control the spread and emergence of AMR in the country. Actions should include active surveillance to monitor the emergence and spread of AMR. Infection prevention and control precautions should also be optimized to limit further spread. Raising awareness is essential to limit inappropriate antibiotics use, and the antibiotic stewardship programs in hospital settings, outpatients, and community pharmacies, should regulate the ongoing use of antimicrobials. PMID:27570847

  1. Rheumatoid arthritis in Saudi Arabia

    PubMed Central

    Almoallim, Hani M.; Alharbi, Laila A.

    2014-01-01

    The status of rheumatoid arthritis (RA) in Saudi Arabia (SA) was examined from various perspectives based on a systematic literature review and the authors’ personal experiences. In this regard, database and journal search were conducted to identify studies on RA in SA, yielding a total of 43 articles. Although efforts have been made to promote RA research in SA, current studies mostly represent only a few centers and may not accurately portray the national status of RA care. Notably, biological therapies were introduced early for almost all practicing rheumatologists in SA (government and private). However, no national guidelines regarding the management of RA have been developed based on local needs and regulations. Also, while efforts were made to establish RA data registries, they have not been successful. Taken together, this analysis can contribute to the planning of future guidelines and directives for RA care in SA. PMID:25491208

  2. Celebrating Saudi Arabia: Using the Five Fundamental Themes of Geography in Order to Discover Saudi Arabia

    ERIC Educational Resources Information Center

    Fitzhugh, William

    2006-01-01

    The Kingdom of Saudi Arabia is a large Arab, Muslim country in the Middle East. It has been an economic and political partner of the United States for many years. This unit, designed for elementary students, provides a text, questions, mapping skills, and fun activities. Students read about Saudi Arabia to gain insights and an appreciation of…

  3. 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.

  4. Flood surge through the Lunae Planum Outflow Complex, Mars

    NASA Technical Reports Server (NTRS)

    De Hon, R. A.; Pani, E. A.

    1992-01-01

    It is shown that the Maja outflow on Mars was released as a catastrophic outburst from Juventae Chasma. The flood surge traveled the first two-thirds of its length as a semiconfined sheetflood in a broad trough formed by the eastward-sloping Lunae Planum surface and the Xanthe Terra highlands to the east. At its northernmost extent, the flow ponded on the northern Lunae Planum surface. As the flow impounded on the upper Maja lake, waters rose to spill over the Xanthe Terra revetment onto the lower Chryse Planitia surface. The initial spillover crossed Xanthe Terra as sheetflood flow that muted topography over which it passed. The sheetflood was rapidly broken by the irregular topography to cut a complex series of anastomosing channels. A few main channels on eventually captured most of the drainage and local ponds formed in breached craters and irregular basins. The Maja Valles canyon eventually captured the remaining flow at the expense of all other channels.

  5. Recent ice ages on Mars.

    PubMed

    Head, James W; Mustard, John F; Kreslavsky, Mikhail A; Milliken, Ralph E; Marchant, David R

    2003-12-18

    A key pacemaker of ice ages on the Earth is climatic forcing due to variations in planetary orbital parameters. Recent Mars exploration has revealed dusty, water-ice-rich mantling deposits that are layered, metres thick and latitude dependent, occurring in both hemispheres from mid-latitudes to the poles. Here we show evidence that these deposits formed during a geologically recent ice age that occurred from about 2.1 to 0.4 Myr ago. The deposits were emplaced symmetrically down to latitudes of approximately 30 degrees--equivalent to Saudi Arabia and the southern United States on the Earth--in response to the changing stability of water ice and dust during variations in obliquity (the angle between Mars' pole of rotation and the ecliptic plane) reaching 30-35 degrees. Mars is at present in an 'interglacial' period, and the ice-rich deposits are undergoing reworking, degradation and retreat in response to the current instability of near-surface ice. Unlike the Earth, martian ice ages are characterized by warmer polar climates and enhanced equatorward transport of atmospheric water and dust to produce widespread smooth deposits down to mid-latitudes.

  6. Arabia and Memnonia Equatorial Regions with High Content of Water: Data from HEND/Odyssey

    NASA Technical Reports Server (NTRS)

    Mitrofaov, I. G.; Litvak, M. L.; Kozyrev, A. S.; Sanin, A. B.; Tretyakov, V. I.; Boynton, W. V.; Hamara, D. K.; Shinohara, C.; Saunders, R. S.

    2004-01-01

    After one martian year of neutron mapping measurements by the High Energy Neutron Detector (HEND) onboard the Mars Odyssey spacecraft, a map of the planet was produced showing the summer season in each hemisphere when winter deposition of CO2 on the surface is absent. The data for northern and southern poleward water-rich regions are presented. Here we discuss the HEND results for two equatorial regions, Arabia and Memnonia, which were found to be associated with a rather strong depression of epithermal and high energy neutrons.

  7. 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.

  8. 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.

  9. Paleotectonism in the Noachis-Sabaea region, Southern Highlands of Mars; Preliminary Modelling and Reconstruction of Events

    NASA Astrophysics Data System (ADS)

    Ruj, T.; Komatsu, G.; Dohm, J. M.; Miyamoto, H.; Salese, F.

    2015-10-01

    Paleotectonism of Mars has been investigated at global to local scales [1], with particular focus on Tharsis and its components [1], [2]. Such examples include the southern and eastern margins of the Thaumasia plateau, namely the Thaumasia highlands and Coprates rise mountain ranges respectively [3], and structurally-controlled basins and associated highly -degraded massifs that are interpreted to be volcanoes such as in the extremely ancient provinces like Terra Sirenum [4] and Terra Cimmeria [5].

  10. Water and methane maps overlap on Mars: a new clue?

    NASA Astrophysics Data System (ADS)

    2004-09-01

    PFS observed that, at 10-15 kilometres above the surface, water vapour is well mixed and uniform in the atmosphere. However, it found that, close to the surface, water vapour is more concentrated in three broad equatorial regions: Arabia Terra, Elysium Planum and Arcadia-Memnonia. Here, the concentration is two to three times higher than in other regions observed. These areas of water vapour concentration also correspond to the areas where NASA’s Odyssey spacecraft has observed a water ice layer a few tens of centimetres below the surface, as Dr Vittorio Formisano, PFS principal investigator, reports. New in-depth analysis of PFS data also confirms that methane is not uniform in the atmosphere, but concentrated in some areas. The PFS team observed that the areas of highest concentration of methane overlap with the areas where water vapour and underground water ice are also concentrated. This spatial correlation between water vapour and methane seems to point to a common underground source. Initial speculation has taken the underground ice layer into account. This could be explained by the ‘ice table’ concept, in which geothermal heat from below the surface makes water and other material move towards the surface. It would then freeze before getting there, due to the very low surface temperature (many tens of degrees Celsius below zero). Further investigations are needed to fully understand the correlation between the ice table and the presence and distribution of water vapour and methane in the atmosphere. In other words, can the geothermal processes which ‘feed’ the ice table also bring water vapour and other gases, like methane, to the surface? Can there be liquid water below the ice table? Can forms of bacterial life exist in the water below the ice table, producing methane and other gases and releasing them to the surface and then to the atmosphere? The PFS instrument has also detected traces of other gases in the Martian atmosphere. A report on these

  11. 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.

  12. 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

  13. Results of Statewide TerraNova Testing, Fall 1998.

    ERIC Educational Resources Information Center

    La Marca, Paul M.

    This summary provides key findings about state, district, and school level performance on the TerraNova examinations (CTB/McGraw Hill) in Nevada in 1998-1999. The TerraNova tests are used to assess students in grades 4, 8, and 10 as stipulated by Nevada law. Within this summary, a description of performance as measured by national percentile…

  14. 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

  15. Role of TERRA in the regulation of telomere length.

    PubMed

    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.

  16. 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.

  17. 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.

  18. Hydrogeology of Basins on Mars

    NASA Astrophysics Data System (ADS)

    Arvidson, Raymond E.

    2001-06-01

    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.

  19. 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 ...

  20. 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".

  1. 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 ...

  2. Mars resources

    NASA Astrophysics Data System (ADS)

    Duke, Michael B.

    1986-05-01

    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.

  3. 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.

  4. KREEP Components in the Dense Ferruginous Basic Mantle of the Subsided Northern Hemisphere of Mars

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2014-11-01

    Lowland basaltic hemispheres of Earth and Moon contain "anomalous" areas of KREEP-like lithologies. Mars is no exception. In the Acidalia Pl. NE of Tempe Terra geochemical mapping reveals K-Th enriched area. It is confined to NE end of areoid bulge.

  5. 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.

  6. Mars crustal magnetism, plate tectonics, and more

    NASA Astrophysics Data System (ADS)

    Connerney, J.; Acuna, M.; Ness, N.

    Mars 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 or TRM). The Mars crust is at least an order of magnitude more intensely magnetized than that of the Earth. The apparent lack of magnetization associated with major impact basins suggests that the crust acquired magnetic remanence early in its history, about 4 billion years ago. A new map of the magnetic field of Mars, compiled at ˜ 400 km mapping altitude by Mars Global Surveyor, is presented here. The spatial resolution and sensitivity of this global map is unprecedented, inviting geologic interpretation heretofor reserved for aeromagnetic and ship surveys on Earth. These data provide new insight into the origin and evolution of the Mars crust. The apparent lack of magnetization associated with volcanic provinces may indicate that the magnetic layer resides within a few km of the surface, requiring magnetization intensity of order few 100 A/m, almost unthinkable. 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 describe the relative motion of two ancient Mars plates on the surface of a sphere. The magnetic imprint in Meridiani is consistent with that observed above a mid-ocean ridge on Earth. It is a relic of an era of plate tectonics on Mars, an era of crustal spreading, rifting, plate motions, and widespread volcanism following the demise of the dynamo. We present this new data in the context of the early development of plate tectonics on Earth, as advanced by the Vine-Matthews hypothesis and the work of W. Jason Morgan and others. Finally, we discuss the next logical steps in Mars exploration: magnetic surveys on global and regional scales.

  7. 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.

  8. 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…

  9. 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…

  10. 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.

  11. 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

  12. Mars Topography

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These maps are global false-color topographic views of Mars at different orientations from the Mars Orbiter Laser Altimeter (MOLA). The maps are orthographic projections that contain over 200,000,000 points and about 5,000,000 altimetric crossovers. The spatial resolution is about 15 kilometers at the equator and less at higher latitudes. The vertical accuracy is less than 5 meters. The right hand image view features the Hellas impact basin (in purple, with red annulus of high standing material). The left hand features the Tharsis topographic rise (in red and white). Note also the subtle textures associated with resurfacing of the northern hemisphere lowlands in the vicinity of the Utopia impact basin. These data were compiled by the Mars Orbiter Laser Altimeter (MOLA) Team led by David Smith at the Goddard Space Flight Center in Greenbelt, MD.

  13. Cracky Mars

    NASA Technical Reports Server (NTRS)

    2006-01-01

    21 September 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows cracked, layered plains-forming material in the western part of Utopia Planitia, Mars. Investigators have speculated that ice might be -- or might once have been -- present in the ground, and changes in temperature and the amount of ice over time may have led to the formation of these cracks. But no one is certain just how these features formed.

    Location near: 45.0oN, 276.1oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

  14. 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.

  15. Detail of terra cotta ornament on southwest corner pier, first ...

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

    Detail of terra cotta ornament on southwest corner pier, first story. Photograph taken 1973. - Scarritt Building & Arcade, Ninth Street & Grand Avenue, & 819 Walnut Street, Kansas City, Jackson County, MO

  16. 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

  17. Detail of secondstory bay with terra cotta ornament on east ...

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

    Detail of second-story bay with terra cotta ornament on east façade. Photograph taken April 1973 - Scarritt Building & Arcade, Ninth Street & Grand Avenue, & 819 Walnut Street, Kansas City, Jackson County, MO

  18. 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.

  19. 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

  20. 4. VIEW NORTH, DETAIL SHOWING TERRA COTTA ROUND ARCH AND ...

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

    4. VIEW NORTH, DETAIL SHOWING TERRA COTTA ROUND ARCH AND STRING COURSE AT FOURTH FLOOR LEVEL AND FRIEZE AT FIFTH FLOOR LEVEL - West Lexington Street, Number 308 (Commercial Building), 308 West Lexington Street, Baltimore, Independent City, MD

  1. Identification of chromatin marks at TERRA promoter and encoding region.

    PubMed

    Negishi, Yutaka; Kawaji, Hideya; Minoda, Aki; Usui, Kengo

    2015-11-27

    TERRA is a long non-coding RNA that is essential for telomere integrity. Although it is transcribed from subtelomeres and telomeres, how it is expressed in heterochromatic region is currently unknown. In this study, we focused our analysis on TERRA-encoding region TelBam3.4 and TelBam3.4-like sequences, and determined their transcription start sites, as well as enrichment of RNA polymerase II and histone modifications. We found that H3K4me3 and H3K9me3 are present at TERRA promoters, whereas H3K27ac and H3K9me3 are present at telomeric repeats. Consistently, we show that presence of active histone modifications H3K4me3 and H3K27ac are correlated to TERRA expression. These results mark an important step towards understanding telomere maintenance and transcription.

  2. 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

  3. 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

  4. Functional characterization of the TERRA transcriptome at damaged telomeres.

    PubMed

    Porro, Antonio; Feuerhahn, Sascha; Delafontaine, Julien; Riethman, Harold; Rougemont, Jacques; Lingner, Joachim

    2014-10-31

    Telomere deprotection occurs during tumorigenesis and aging upon telomere shortening or loss of the telomeric shelterin component TRF2. Deprotected telomeres undergo changes in chromatin structure and elicit a DNA damage response (DDR) that leads to cellular senescence. The telomeric long noncoding RNA TERRA has been implicated in modulating the structure and processing of deprotected telomeres. Here, we characterize the human TERRA transcriptome at normal and TRF2-depleted telomeres and demonstrate that TERRA upregulation is occurring upon depletion of TRF2 at all transcribed telomeres. TRF2 represses TERRA transcription through its homodimerization domain, which was previously shown to induce chromatin compaction and to prevent the early steps of DDR activation. We show that TERRA associates with SUV39H1 H3K9 histone methyltransferase, which promotes accumulation of H3K9me3 at damaged telomeres and end-to-end fusions. Altogether our data elucidate the TERRA landscape and defines critical roles for this RNA in the telomeric DNA damage response.

  5. 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

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

    PubMed

    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

    2015-11-17

    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.

  7. 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

  8. 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.

  9. Acidic Conditions During Open System Weathering on Late Noachian/Early Hesperian Mars? Newly Identified Outcrops of Alunite and Jarosite from Orbital CRISM Data

    NASA Astrophysics Data System (ADS)

    Ehlmann, Bethany; Dundar, Murat

    2016-10-01

    Sequences of Al-phyllosilicates atop Fe,Mg-phylloslicates occur in multiple regions of Mars, including Mawrth Vallis/northern Arabia Terra, Nili Fossae/Northeast Syrtis Major, Terra Sirenum/Eridania basin, northern Hellas, and portions of Valles Marineris. The sequences are exposed beneath unaltered capping materials with Early Hesperian surface ages, thus implying phyllosilicate formation occurred earlier. Because of the presence of clay minerals, the sequences are certainly a product of water interactions with rocks and sediments, but key questions remain about the environmental conditions implied. Are Al-phyllosilicates simply a result of alteration of a silicic precursor? Or do they represent the end product of substantial open system leaching of a basaltic protolith? Was open system leaching substantial because of high water throughput, long cumulative duration, acidity, or some combination? Each scenario leads to Al-phyllosilicate formation but with different accompanying mineral phases in response to pH, Eh, and chemical species concentrations in the fluids. Key to further progress in constraining the environmental conditions of alteration is more sophisticated spectral analyses to identify intermixed phases and isolate rare spectral classes within the Al phyllosilicate units.Here, we employ a newly developed, non-parametric Bayesian algorithm [1] for semi-automatic identification of rare spectral classes. We employ this algorithm on 139 CRISM images in areas with reported regional-scale occurrences of Al-phyllosilicates that were compiled from the literature [e.g. 2, 3]. Dozens of detections of the minerals alunite and jarosite were made with the algorithm and then verified by manual analysis. These sulfate hydroxides form only at low pHs, and thus their presence tightly constrains water chemistry. Crucial for understanding whether the alunite and jarosite deposits are contemporaneous with the Al phyllosilicates or later overprinting deposits is study of

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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…

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

    ERIC Educational Resources Information Center

    Alquraini, Turki

    2010-01-01

    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…

  20. 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... networking reception. U.S. participants will be counseled before and after the mission by the domestic...; Meetings with CS Saudi Arabia's ICT industry specialists in Riyadh and Jeddah; and Networking reception...

  1. 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.

  2. 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.

  3. Evidences for a Noachian Hesperian orogeny in Mars

    NASA Astrophysics Data System (ADS)

    Anguita, Francisco; Fernández, Carlos; Cordero, Guadalupe; Carrasquilla, Sandra; Anguita, Jorge; Núñez, Andrés; Rodríguez, Sergio; García, Judit

    2006-12-01

    A number of tectonic structures have been located at the Thaumasia Plateau, Daedalia Planum and Aonia Terra, Mars. They include isolated folds with axial traces up to 200 km long, trains of tightly folded structures tens of km long, and thrusts. Their size and geometry are similar to those on Earth, and the direction of compression seems to have varied amply with time, suggesting a complex tectonic evolution. Crater counts on the deformed terrain point to Noachian to Early Hesperian ages. On the basis of the geometry and geological relations of these structures, we propose that they form part of an old martian orogen, the Thaumasia-Aonia Orogen, which embraced not only the Thaumasia Plateau, but areas of Daedalia Planum, Aonia Terra and Nereidum Montes as well. A regional coherent layering is previous to the deformation and could represent the trace of even older stresses on the martian lithosphere.

  4. 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.

  5. Sol-Terra - AN Operational Space Weather Forecasting Model Framework

    NASA Astrophysics Data System (ADS)

    Bisi, M. M.; Lawrence, G.; Pidgeon, A.; Reid, S.; Hapgood, M. A.; Bogdanova, Y.; Byrne, J.; Marsh, M. S.; Jackson, D.; Gibbs, M.

    2015-12-01

    The SOL-TERRA project is a collaboration between RHEA Tech, the Met Office, and RAL Space funded by the UK Space Agency. The goal of the SOL-TERRA project is to produce a Roadmap for a future coupled Sun-to-Earth operational space weather forecasting system covering domains from the Sun down to the magnetosphere-ionosphere-thermosphere and neutral atmosphere. The first stage of SOL-TERRA is underway and involves reviewing current models that could potentially contribute to such a system. Within a given domain, the various space weather models will be assessed how they could contribute to such a coupled system. This will be done both by reviewing peer reviewed papers, and via direct input from the model developers to provide further insight. Once the models have been reviewed then the optimal set of models for use in support of forecast-based SWE modelling will be selected, and a Roadmap for the implementation of an operational forecast-based SWE modelling framework will be prepared. The Roadmap will address the current modelling capability, knowledge gaps and further work required, and also the implementation and maintenance of the overall architecture and environment that the models will operate within. The SOL-TERRA project will engage with external stakeholders in order to ensure independently that the project remains on track to meet its original objectives. A group of key external stakeholders have been invited to provide their domain-specific expertise in reviewing the SOL-TERRA project at critical stages of Roadmap preparation; namely at the Mid-Term Review, and prior to submission of the Final Report. This stakeholder input will ensure that the SOL-TERRA Roadmap will be enhanced directly through the input of modellers and end-users. The overall goal of the SOL-TERRA project is to develop a Roadmap for an operational forecast-based SWE modelling framework with can be implemented within a larger subsequent activity. The SOL-TERRA project is supported within

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

    PubMed

    Abdel-Razek, Moheb M; Fathy, Hanan

    2015-10-16

    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.

  7. Atypical presentations of terra firma-forme dermatosis.

    PubMed

    Thomas, Richard Scott; Collins, Jeffrey; Young, Russel John; Bohlke, Angela

    2015-01-01

    Terra firma-forme dermatosis is a benign dermatologic condition that presents as dirt-colored patches and plaques, mainly affecting children and adolescents. It is resistant to conventional washing with soap and water but is easily treated with isopropyl alcohol. Clinical awareness of this condition provides a quick, simple resolution. Here we present two cases involving 14-year-old girls with uncommon presentations of terra firma-forme dermatosis. One case involved an upper extremity and the other presented with a history of knee brace occlusion. After diagnosis, both patients were successfully treated with weekly isopropyl alcohol applications.

  8. An observational search for carbonates on Mars

    NASA Astrophysics Data System (ADS)

    Blaney, Diana L.; McCord, Thomas B.

    1989-08-01

    Results are presented from a search for carbonates and other salts on the surface of Mars, using the 2.2-m telescope at the Mauna Kea Observatory (Hawaii) for observations, in the 2.6 to 4.2 micron spectral region, within four Mars areas, including Syrtis Major, Hellas, Arabia, and an area northeast of Hellas. Shallow depressions in the reflectance spectra of two partially overlapping areas (the overlap of which contains Syrtis Planum) were observed between 3.8 and 3.9 microns (i.e., in the region where carbonate absorptions appear), the strength of which is consistent with the presence of 5 to 10 wt pct magnesium carbonate in the upper few millimeters of Mars soil. However, the depressions are slightly shorter in wavelength and broader in shape than the magnesium carbonate band. The depressions are too short in wavelength to be caused by calcium carbonate. Results of these and earlier observations do not rule out carbonates below the surface in other locations, or in concentrations of less than 3 to 5 percent in the areas observed.

  9. California and Saudi Arabia: geologic contrasts

    SciTech Connect

    Alexander, R.G. Jr.

    1984-09-01

    Assessing hydrocarbon futures in unexplored basins involves geology by analogy. Through 1978, approximately 265 fields were discovered in California containing 22 billion bbl of oil, 53% being in the 10 largest fields, ranging in size from 0.6 to 2.4 billion bbl. Through 1978, about 50 fields were found in Saudi Arabia containing 206 billion bbl of oil, 78% in the 10 largest fields, ranging in size from 7 to 83 billion bbl. The contrasts in field size distribution and in the total amount of oil present are explained by the dramatically different geology and geologic histories. California's surface geology is characterized by rare Precambrian, isolated Paleozoic, and widespread Mesozoic accreted terranes and intrusions, and by highly uplifted and depressed Tertiary sedimentary prisms bounded by widespread high-angle thrusting and strike-slip and normal faulting. Numerous families of medium to small anticlines and fault traps, commonly involving moderately dipping to overturned beds, have resulted from Tertiary tectonism, which segmented California dramatically. Saudi Arabia is characterized by a broad Precambrian shield area, flanked on the east by very long, gently dipping cuestas of Paleozoic and Mesozoic sediments, with an upper thin veneer of nearly flat Tertiary strata. Most structures involving the Mesozoic and Cenozoic are large, but gentle and unfaulted, representing a passive reaction of the sediments to underlying mild basement distortion and/or movement of Cambrian salt, all occurring while the arabian plate continued to subside and tip to the northeast. The contrasts between California and Saudi Arabia oil field and geology result from contrasting plate-tectonic settings and history.

  10. 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.

  11. Geologic Map of MTM 35337, 40337, and 45337 Quadrangles, Deuteronilus Mensae Region of Mars

    USGS Publications Warehouse

    Chuang, Frank C.; Crown, David A.

    2009-01-01

    Deuteronilus Mensae, first defined as an albedo feature at lat 35.0 deg N., long 5.0 deg E., by U.S. Geological Survey (USGS) and International Astronomical Union (IAU) nomenclature, is a gradational zone along the dichotomy boundary in the northern mid-latitudes of Mars. The boundary in this location includes the transition from the rugged cratered highlands of Arabia Terra to the northern lowland plains of Acidalia Planitia. Within Deuteronilus Mensae, polygonal mesas are prominent along with features diagnostic of Martian fretted terrain, including lobate debris aprons, lineated valley fill, and concentric crater fill. Lobate debris aprons, as well as the valley and crater fill deposits, are geomorphic indicators of ground ice, and their concentration in Deuteronilus Mensae is of great interest because of their potential association with Martian climate change. The paucity of impact craters on the surfaces of debris aprons and the presence of ice-cemented mantle material imply young (for example, Amazonian) surface ages that are consistent with recent climate change in this region of Mars. North of Deuteronilus Mensae are the northern lowlands, a potential depositional sink that may have had large standing bodies of water or an ocean in the past. The northern lowlands have elevations that are several kilometers below the ancient cratered highlands with significantly younger surface ages. The morphologic and topographic characteristics of the Deuteronilus Mensae region record a diverse geologic history, including significant modification of the ancient highland plateau and resurfacing of low-lying regions. Previous studies of this region have interpreted a complex array of geologic processes, including eolian, fluvial and glacial activity, coastal erosion, marine deposition, mass wasting, tectonic faulting, effusive volcanism, and hydrovolcanism. The origin and age of the Martian crustal dichotomy boundary are fundamental questions that remain unresolved at the

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

    PubMed

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

    2013-12-01

    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.

  13. Terra Vac In Situ Vacuum Extraction System: Applications Analysis Report

    EPA Science Inventory

    This document is an evaluation of the Terra Vac in situ vacuum extraction system and its applicability as a treatment method for waste site cleanup. This report analyzes the results from the Superfund Innovative Technology Evaluation (SITE) Program’s 56-day demonstration at t...

  14. 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

    2016-08-18

    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.

  15. 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...

  16. Telomeric Repeat Containing RNA (TERRA): Aging and Cancer.

    PubMed

    Sinha, Sonam; Shukla, Samriddhi; Khan, Sajid; Farhan, Mohammad; Kamal, Mohammad Amjad; Meeran, Syed Musthapa

    2015-01-01

    Telomeric repeat containing RNAs (TERRA) are small RNA molecules synthesized from telomeric regions which were previously considered as silent genomic domains. In normal cells, these RNAs are transcribed in a direction from subtelomeric region towards the chromosome ends, but in case of cancer cells, their expression remains limited or absent. Telomerase is a rate limiting enzyme for cellular senescence, cancer and aging. Most of the studies deal with the manipulation of telomerase enzyme in cancer and aging either by synthetic oligonucleotide or by natural phytochemicals. Here, we collected evidences and discussed intensely about the bio-molecular structure of TERRA, naturally occurring ligands of telomerase, and their genetic and epigenetic regulations in aging associated diseases. Due to their capability to act as naturally occurring ligands of telomerase, these RNAs can overcome the limitations possessed by synthetic oligonucleotides, which are aimed against telomerase. Drugs specifically targeting TERRA molecules could modulate telomerase-mediated telomere lengthening. Thus, targeting TERRA-mediated regulation of telomerase would be a promising therapeutic strategy against cancer and age-associated diseases.

  17. Bilateral topographic symmetry patterns across Aphrodite Terra, Venus

    SciTech Connect

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

    1988-01-10

    Western Aphrodite Terra, Venus, is characterized by a series of parallel linear structural discontinuities 2000--4000 km in length and 100--200 km wide, which strike at high angles to the general topographic trend of the Aphrodite Terra highlands. The broad chracteristics of the cross-strike discontinuities (CSDs) are similar to both strike-slip fault zones and terrestrial oceanic fracture zones. In an effort to distinguish between these two hypotheses, topographic profiles were taken 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 observed within domains between linear discontinuities in directions generally parallel to the strike of the discontinuities. In addition, within a domain the centers of symmetry of several profiles define a linear rise crest that is oriented normal to the bounding CSDs and terminates against them.

  18. 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

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. MarsSat: assured communication with Mars.

    PubMed

    Gangale, Thomas

    2005-12-01

    The author developed the MarsSat concept during the 1990s. For this task, he designed a class of orbits to solve the problem of communicating with crews on Mars when the planet is in solar conjunction as seen from Earth, a planetary configuration that occurs near the midpoint of a conjunction class mission to Mars. This type of orbit minimizes the distance between Mars and the communications satellite; thus, minimizing the size, weight, and power requirements, while providing a simultaneous line-of-sight to both Earth and Mars. The MarsSat orbits are solar orbits that have the same period as Mars, but are inclined a few degrees out of the plane of the Mars orbit and also differ in eccentricity from the orbit of Mars. These differences cause a spacecraft in this orbit to rise North of Mars, then fall behind Mars, then drop South of Mars, and then pull ahead of Mars, by some desired distance in each case-typically about 20 million kilometers-in order to maintain an angular separation of a couple of degrees as seen from a point in the orbit of Earth on the opposite side of the Sun. A satellite in this type of orbit would relay communications between Earth and Mars during the period of up to several weeks, when direct communication is blocked by the Sun. These orbits are far superior for this purpose when compared to stationing a satellite at one of the Sun-Mars equilateral Lagrangian points, L(4) or L(5), for two reasons. First, L(4) and L(5) are 228 million kilometers from Mars, about 10 times the distance of a spacecraft in one of the MarsSat orbits, and by virtue of the inverse-square law, all other things being equal, the signal strength received at L(4) or L(5) would be one percent of the signal strength received by a spacecraft in one of the MarsSat orbits. Thus, a relay satellite stationed at L(4) or L(5) would have to be that much more powerful to receive data at the same rate, with concomitant increases in spacecraft size and weight. Second, a number of

  6. Telomeric noncoding RNA TERRA is induced by telomere shortening to nucleate telomerase molecules at short telomeres.

    PubMed

    Cusanelli, Emilio; Romero, Carmina Angelica Perez; Chartrand, Pascal

    2013-09-26

    Elongation of a short telomere depends on the action of multiple telomerase molecules, which are visible as telomerase RNA foci or clusters associated with telomeres in yeast and mammalian cells. How several telomerase molecules act on a single short telomere is unknown. Herein, we report that the telomeric noncoding RNA TERRA is involved in the nucleation of telomerase molecules into clusters prior to their recruitment at a short telomere. We find that telomere shortening induces TERRA expression, leading to the accumulation of TERRA molecules into a nuclear focus. Simultaneous time-lapse imaging of telomerase RNA and TERRA reveals spontaneous events of telomerase nucleation on TERRA foci in early S phase, generating TERRA-telomerase clusters. This cluster is subsequently recruited to the short telomere from which TERRA transcripts originate during S phase. We propose that telomere shortening induces noncoding RNA expression to coordinate the recruitment and activity of telomerase molecules at short telomeres.

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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

  13. 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

  14. Mars Global Surveyor: Cruising to Mars

    NASA Technical Reports Server (NTRS)

    Cunningham, Glenn E.

    1997-01-01

    The Mars Global Surveyor spacecraft was launched on November 7, 1996, and is now cruising to Mars. While the launch was excellent, and the spacecraft and its science payload are in perfect operating condition, a broken deployment damper on one of the two solar arrays has posed some concern relative to the use of that solar array as a drag surfae during aerobraking operations at Mars.

  15. 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.

  16. 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

  17. Assisted reproductive technology in Saudi Arabia.

    PubMed

    Abduljabbar, Hassan S; Amin, Rubina

    2009-04-01

    This paper aims at presenting details of the application of assisted reproductive technology and the impact of the Islamic law (Sharia) on its practice in the Kingdom of Saudi Arabia (KSA). Analysis of the data sourced from manual searches of bibliographies from key articles showed that this technology in KSA is practiced in a strictly religious manner and certain aspects of the technology are completely forbidden. It further showed that lack of an official government in-vitro fertilization (IVF) registry to gather information on the activities of IVF clinics has limited the data available for international comparisons. Sharing information internationally could allow religiously concerned infertile couples to have access to the reproductive services in the Kingdom. It would further improve the quality of care, enhance certain techniques like in-vitro maturation and experimentation on embryos, by providing resources that are currently unavailable, keeping in view the religious beliefs and avoiding conflicts. PMID:19370268

  18. Assisted reproductive technology in Saudi Arabia.

    PubMed

    Abduljabbar, Hassan S; Amin, Rubina

    2009-04-01

    This paper aims at presenting details of the application of assisted reproductive technology and the impact of the Islamic law (Sharia) on its practice in the Kingdom of Saudi Arabia (KSA). Analysis of the data sourced from manual searches of bibliographies from key articles showed that this technology in KSA is practiced in a strictly religious manner and certain aspects of the technology are completely forbidden. It further showed that lack of an official government in-vitro fertilization (IVF) registry to gather information on the activities of IVF clinics has limited the data available for international comparisons. Sharing information internationally could allow religiously concerned infertile couples to have access to the reproductive services in the Kingdom. It would further improve the quality of care, enhance certain techniques like in-vitro maturation and experimentation on embryos, by providing resources that are currently unavailable, keeping in view the religious beliefs and avoiding conflicts.

  19. 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.

  20. Mars exploration mission

    NASA Astrophysics Data System (ADS)

    Matsuda, Seiji

    1991-07-01

    Mars exploration scenarios are reviewed. An emphasis is placed on scientific exploration. The review and evaluation results are reported for the following items: (1) orbit plans for Mars surface exploration missions that begin in Low Earth Orbit (LEO); (2) powered and aerodynamic capturing payloads from the transfer orbit to a Mars revolving orbit; and (3) a penetrator system as a Mars landing vehicle. Proposed Mars transfer orbits have the following advantages over Hohmann orbits: (1) transfer time and angle are less; (2) the inclination between the orbital planes of Earth and Mars is considered; and (3) velocity variations are not required to change orbit plane.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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...

  12. Mars Airborne Prospecting Spectrometer

    NASA Astrophysics Data System (ADS)

    Steinkraus, J. M.; Wright, M. W.; Rheingans, B. E.; Steinkraus, D. E.; George, W. P.; Aljabri, A.; Hall, J. L.; Scott, D. C.

    2012-06-01

    One novel approach towards addressing the need for innovative instrumentation and investigation approaches is the integration of a suite of four spectrometer systems to form the Mars Airborne Prospecting Spectrometers (MAPS) for prospecting on Mars.

  13. Mars Meteorolgical Network

    NASA Technical Reports Server (NTRS)

    Justh, H. L.; Spann, J. F.

    2012-01-01

    Exploring and ultimately establishing a permanent presence on the surface of Mars will necessitate an understanding the weather conditions and the ability to forecast its dynamic behavior. The meteorology of Mars will need to be developed. This abstract puts forth a concept for a Mars Meteorological Network that will be used to investigate the Mars atmosphere behavior, explore the surface environment, and prepare for operational activities. It is proposed that the long term and the dynamic nature of the lower atmosphere and surface of Mars be observed with a distributed global array of simple automated surface nodes. The data would be ingested into the Mars Global Reference Atmospheric Model (Mars-GRAM) and other research tools for analyses to gain a better understanding of the atmospheric conditions on Mars.

  14. 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...

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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…

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. Mantle plumes and associated flow beneath Arabia and East Africa

    NASA Astrophysics Data System (ADS)

    Chang, Sung-Joon; Van der Lee, Suzan

    2011-02-01

    We investigate mantle plumes and associated flow beneath the lithosphere by imaging the three-dimensional S-velocity structure beneath Arabia and East Africa. This image shows elongated vertical and horizontal low-velocity anomalies down to at least mid mantle depths. This three-dimensional S-velocity model is obtained through the joint inversion of teleseismic S- and SKS-arrival times, regional S- and Rayleigh waveform fits, fundamental-mode Rayleigh-wave group velocities, and independent Moho constraints from receiver functions, reflection/refraction profiles, and gravity measurements. In the resolved parts of our S-velocity model we find that the Afar plume is distinctly separate from the Kenya plume, showing the Afar plume's origin in the lower mantle beneath southwestern Arabia. We identify another quasi-vertical low-velocity anomaly beneath Jordan and northern Arabia which extends into the lower mantle and may be related to volcanism in Jordan, northern Arabia, and possibly southern Turkey. Comparing locations of mantle plumes from the joint inversion with fast axes of shear-wave splitting, we confirm horizontal mantle flow radially away from Afar. Low-velocity channels in our model support southwestward flow beneath Ethiopia, eastward flow beneath the Gulf of Aden, but not northwestwards beneath the entire Red Sea. Instead, northward mantle flow from Afar appears to be channeled beneath Arabia.

  7. 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.

  8. Northern Saudi Arabia as seen from STS-62

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Great numbers of circular, center-pivot irrigation plots appear in this west-looking view of northern Saudi Arabia (center to lower left). The entire country between the shifting sands of the Ad Dahna Sand Sea (light colors center and right) and the almost soilless Nejd Plateau (left) has been darkened by thousands of these agricultural fields. The Nejd Plateau is a mass of dark rocks, some volcanic, in northwest Saudi Arabia. The sweep of the Ad Dahna Sand Sea is one of the major features of Saudi Arabia (center and right) as seen from the orbiter. The dunes follow the trend of regional winds (northwesterly in the center of the view) which circulates around the Nejd plateau. The north end of the Red Sea can be seen top left with the Sinai Peninsula and Mediterranean are just visible center top. Iraq is under clouds top right.

  9. The respiratory care profession in Saudi Arabia: Past and present

    PubMed Central

    Al-Otaibi, Hajed M.; AlAhmari, Mohammed Dhafer

    2016-01-01

    The respiratory care (RC) profession in Saudi Arabia is over 40-year-old. Although there have been major advancements in the profession, no history and enough information are available about its development and evolvement at current. This paper describes the history and development of the field of RC and future prospects for the profession in Saudi Arabia. A comprehensive review and assessment were conducted through direct contact, interviews, and a review of existing documents in the Medical Services Division of the Ministry of Defense, the Ministry of Health, The Ministry of Civil Services, representative hospitals, academic institutions, and other relevant texts. The data obtained were evaluated for its relevance and grouped on a thematic basis. This is currently the first paper about the history and development of the RC profession in Saudi Arabia over the last 45 years. PMID:27803748

  10. Rabies in Saudi Arabia: a need for epidemiological data.

    PubMed

    Memish, Ziad A; Assiri, Abdullah M; Gautret, Philippe

    2015-05-01

    Rabies is endemic in animals in the Arabian Peninsula. Although Saudi Arabia is the largest country in the Peninsula, little has been published about the rabies situation in the country. A total of 11,069 animal bites to humans were reported during 2007-2009, and 40 animals suspected of rabies were examined for rabies infection from 2005 through 2010. Results suggest that animal-related injuries in Saudi Arabia remain a public health problem, with feral dogs accounting for the majority of bites to humans and for the majority of animals found to be rabid. Over the last 10 years, no confirmed human rabies case has been reported. More detailed information about the epidemiology of animal bites and that of animal rabies in Saudi Arabia would be of great interest, notably to provide a basis on which vaccination recommendations could be made for the numerous international travellers visiting the country.

  11. 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

  12. Barriers to Peritoneal Dialysis in Saudi Arabia: Nephrologists' Perspectives.

    PubMed

    Dahlan, Randah; Qureshi, Mohammad; Akeely, Fatmah; Al Sayyari, Abdullah A

    In Saudi Arabia, only 9% of dialysis patients are on peritoneal dialysis (PD), and this has been the case for years. A number of centers around the world have sought to understand the underutilization of PD by asking nephrologists directly. In this study, we aimed to gather information that will answer the question "Why is PD underutilized in Saudi Arabia?" hoping that a roadmap may be developed to overcome the hurdles the study underscores, allowing for more patients to utilize this valuable modality. PMID:27659929

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Spacecraft exploration of Mars

    NASA Technical Reports Server (NTRS)

    Snyder, Conway W.; Moroz, Vasilii I.

    1992-01-01

    Soviet and American spacecraft exploration of Mars over the past quarter century is reviewed. Data on the earliest Soviet attempts to send spacecraft to observe the planet are presented. Of the series of spacecraft that were announced (designated Mars 1 to Mars 7), none fulfilled all its scientific goals, but some good photographs and other important data were obtained. Of the six spacecraft in the Mariner series, two failed, but Mariner 4 first revealed the cratered surface of Mars, and Mariner 9 discovered all the major geologic features. The Viking mission, with its two Orbiters, two Landers, and its 6-yr duration, surpassed in quantity and variety of data all other missions combined. The Phobos mission ended in two failures, but the second of the two spacecraft acquired significant new data about Mars and Phobos. An appendix listing special issues of journals containing collections of papers about Mars is provided.

  20. 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...

  1. 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...

  2. Mechanochemical properties of individual human telomeric RNA (TERRA) G-quadruplexes.

    PubMed

    Yangyuoru, Philip M; Zhang, Amy Y Q; Shi, Zhe; Koirala, Deepak; Balasubramanian, Shankar; Mao, Hanbin

    2013-10-11

    Potential functions: By following the unfolding and refolding of individual human RNA telomeric (TERRA) G-quadruplexes (GQs) in laser tweezers, the mechanical stability and transition kinetics of RNA GQs are obtained. Comparison between TERRA and DNA GQs suggests their different regulatory capacities for processes associated with human telomeres.

  3. 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

  4. 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.

  5. Identification of TERRA locus unveils a telomere protection role through association to nearly all chromosomes.

    PubMed

    López de Silanes, Isabel; Graña, Osvaldo; De Bonis, Maria Luigia; Dominguez, Orlando; Pisano, David G; Blasco, Maria A

    2014-09-03

    Telomeric RNAs (TERRAs) are UUAGGG repeat-containing RNAs that are transcribed from the subtelomere towards the telomere. The precise genomic origin of TERRA has remained elusive. Using a whole-genome RNA-sequencing approach, we identify novel mouse transcripts arising mainly from the subtelomere of chromosome 18, and to a lesser extend chromosome 9, that resemble TERRA in several key aspects. Those transcripts contain UUAGGG-repeats and are heterogeneous in size, fluctuate in abundance in a TERRA-like manner during the cell cycle, are bound by TERRA RNA-binding proteins and are regulated in a manner similar to TERRA in response to stress and the induction of pluripotency. These transcripts are also found to associate with nearly all chromosome ends and downregulation of the transcripts that originate from chromosome 18 causes a reduction in TERRA abundance. Interestingly, downregulation of either chromosome 18 transcripts or TERRA results in increased number of telomere dysfunction-induced foci, suggesting a protective role at telomeres.

  6. 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.

  7. NASA's Terra Spacecraft Eyes Smoke Plumes from Massive Rim Fire Near Yosemite

    Atmospheric Science Data Center

    2014-05-15

    article title:  NASA's Terra Spacecraft Eyes Smoke Plumes from Massive Rim Fire Near Yosemite ... Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra spacecraft, showing extensive, brownish smoke. The imaged area ... Center. JPL is a division of the California Institute of Technology. Image Credit: NASA/GSFC/LaRC/JPL, MISR Team ...

  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. 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.

  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. 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.

  12. 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

  13. Why did Arabia separate from Africa ?

    NASA Astrophysics Data System (ADS)

    Bellahsen, N.; Faccenna, C.; Funiciello, F.; Daniel, J. M.; Jolivet, L.

    2003-04-01

    We have performed 3-D scaled lithospheric experiments to investigate the role of the gravitational force exerted by subduction slab on the deformation of the subducting plate itself. Experiments have been constructed using a dense silicone putty plate, to simulate a thin viscous lithosphere, floated in glucose syrup, simulating the upper mantle. We show different plate configuration: (i) subduction of a uniform oceanic plate, (ii) subduction of oceanic-continental plate system, and (iii) subduction of a more complex oceanic-continental system simulating the asymmetric Africa-Eurasia system at the beginning of the Tertiary. Each model has been performed including or not the presence of circular weak zone inside the subducting plate simulating the near-surface weakening effect of a plume activity. Our results show that a subducting plate can deform in its interior only if the velocity field generated by the slab varies laterally along the subduction zone, i.e. by the asymmetrical entrance of continental material at trench. The result of this study can be used to analyze the formation of the Arabian plate. We found that intraplate stresses, similar to the one that generated the Africa-Arabia break-up, can be related to the Neogene evolution of the northern convergent margin of the African plate where a lateral change from collision (Mediterranean and Bitlis) to active subduction (Makran) has been described. Second, intraplate stress and strain localization are favored by the presence of a weakness zone, such as the one generated by the Afar plume, producing a pattern of extensional deformation belts resembling to the Red Sea-Gulf of Aden rift system.

  14. 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…

  15. 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.

  16. 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

  17. Mars Atmospheric Dynamics

    NASA Technical Reports Server (NTRS)

    Haberle, Robert; DeVincenzi, Donald (Technical Monitor)

    1998-01-01

    The Martian atmosphere is dynamically similar to the Earth's. Its spin-axis rotation rate is only minutes longer than Earth's so the Coriolois force is nearly identical to Earth's. The inclination of its spin axis is also similar to Earth's giving it similarity in seasonal change. And the Martian atmosphere is nearly transparent to solar radiation (except during dust periods) such that it is heated primarily by upwelling infrared radiation from the surface. These characteristics make Mars an ideal laboratory for studying the dynamics of rapidly rotating differentially heated atmospheres. This talk reviews what we have learned about Mars atmospheric dynamics and how if compares with Earth. The source of information to make such a comparison comes from observations and models. The former are sparse and that the latter have played a major role in shaping our thinking about the general circulation on Mars. However, the models need validation. Fortunately, the first two orbiters in NASA's Mars Surveyor Program have instrumentation to address many of the issues related to the general circulation and climate of Mars. The first, Mars Global Surveyor, is already at Mars gathering data. The second, the Mars 98 Orbiter to be launched later this year, carries a dedicated atmospheric sounder. Thus, much will be learned about Mars' atmosphere in the next few years.

  18. 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.

  19. Mars - Destination and challenge

    NASA Technical Reports Server (NTRS)

    Aldrich, Arnold D.

    1992-01-01

    A general evaluation is conducted of the challenges associated with prospective Mars exploration efforts. The technical challenge posed stems from the unforgiving physical environment of space travel, and such peculiarities of Mars as its great orbital eccentricity and 15-year cyclic variation in transfer energy. Additional considerations arise from the 'architecture' of NASA's Space Exploration Initiative, encompassing the determination of a Mars exploration effort's purpose, scope, and schedule. Finally, numerous unresolved issues arise from the definition of detailed scientific experimentation that is to be done for the sake of the greatest long-term benefit to an understanding of Mars, and the rallying of political support behind a major new exploration initiative.

  20. 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.

  1. 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.

  2. Mars Museum Visualization Alliance

    NASA Astrophysics Data System (ADS)

    Sohus, A. M.; Viotti, M. A.; de Jong, E. M.

    2004-11-01

    The Mars Museum Visualization Alliance is a collaborative effort funded by the Mars Public Engagement Office and supported by JPL's Informal Education staff and the Solar System Visualization Project to share the adventure of exploration and make Mars a real place. The effort started in 2002 with a small working group of museum professionals to learn how best to serve museum audiences through informal science educators. By the time the Mars Exploration Rovers landed on Mars in January 2004, over 100 organizations were partners in the Alliance, which has become a focused community of Mars educators. The Alliance provides guaranteed access to images, information, news, and resources for use by the informal science educators with their students, educators, and public audiences. Thousands of people have shared the adventure of exploring Mars and now see it as a real place through the efforts of the Mars Museum Visualization Alliance partners. The Alliance has been lauded for "providing just the right inside track for museums to do what they do best," be that webcasts, live presentations with the latest images and information, high-definition productions, planetarium shows, or hands-on educational activities. The Alliance is extending its mission component with Cassini, Genesis, Deep Impact, and Stardust. The Mars Exploration and Cassini Programs, as well as the Genesis, Deep Impact, and Stardust Projects, are managed for NASA by the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California.

  3. Climatic change on Mars.

    NASA Technical Reports Server (NTRS)

    Sagan, C.; Toon, O. B.; Gierasch, P. J.

    1973-01-01

    It is pointed out that Mars is the only known planet with a major atmospheric constituent condensable at typical surface temperatures. The temperatures range from 290 K at equatorial noon to a temperature at the cold pole of 145 K in polar winter. There may be three different periods of climatic variation on Mars. Aspects of reversible climatic instability might possibly explain the channels and other features suggestive of the extensive occurrence of liquid water on Mars. An aqueous epoch on Mars would have important biological and other geological implications. Putative Martian organisms which flourish in the aqueous epoch may now be in cryptobiotic repose.

  4. 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.

  5. 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

  6. 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

  7. 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…

  8. 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

  9. 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…

  10. 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)

  11. 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…

  12. 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…

  13. 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…

  14. 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.

  15. 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…

  16. 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

  17. 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

  18. 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…

  19. 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…

  20. 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.

  1. 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…

  2. Seroprevalence of Alkhurma and other hemorrhagic fever viruses, Saudi Arabia.

    PubMed

    Memish, Ziad A; Albarrak, Ali; Almazroa, Mohammad A; Al-Omar, Ibrahim; Alhakeem, Rafat; Assiri, Abdullah; Fagbo, Shamsudeen; MacNeil, Adam; Rollin, Pierre E; Abdullah, Nageeb; Stephens, Gwen

    2011-12-01

    A 2009 deployment of military units from several Saudi Arabian provinces to Jazan Province, Saudi Arabia, enabled us to evaluate exposure to Alkhurma, Crimean-Congo, dengue, and Rift Valley hemorrhagic fever viruses. Seroprevalence to all viruses was low; however, Alkhurma virus seroprevalence was higher (1.3%) and less geographically restricted than previously thought.

  3. 75 FR 21598 - Energy and Infrastructure Mission to Saudi Arabia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-26

    ... construction materials and products from leading international suppliers. Mission Goals The short term goals of... related to the petrochemical industry. Construction At a time when some Middle Eastern countries are... projects awarded, the Saudi construction sector is rolling forward. Saudi Arabia's ambitious rail plans...

  4. 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)

  5. 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.

  6. 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.

  7. 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…

  8. 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.

  9. 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.

  10. Mars' grand finale

    NASA Astrophysics Data System (ADS)

    Parker, D. C.; Beish, J. D.; Hernandez, C. E.

    1989-04-01

    Results are presented from observations of the 1988 Mars apparition. Consideration is given to observations of the Martian south polar cap, meteorological activity on the planet, and changes in the surface features of Mars during the apparition. Also, the Martian dust storms observed in November 1988 are described.

  11. Dust devils on Mars.

    PubMed

    Thomas, P; Gierasch, P J

    1985-10-11

    Columnar, cone-shaped, and funnel-shaped clouds rising 1 to 6 kilometers above the surface of Mars have been identified in Viking Orbiter images. They are interpreted as dust devils, confirming predictions of their occurrence on Mars and giving evidence of a specific form of dust entrainment.

  12. 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.

  13. 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…

  14. 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.

  15. Mars ice caps.

    PubMed

    Leovy, C

    1966-12-01

    Minimum atmospheric temperatures required to prevent CO(2) condensatio in the Mars polar caps are higher than those obtained in a computer experiment to simulate the general circulation of the Mars atmosphere. This observation supports the view that the polar caps are predominantly solid CO(2). However, thin clouds of H(2)0 ice could substantially reduce the surface condensation rate.

  16. 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.

  17. 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.

  18. Surface Drainage on Mars

    NASA Technical Reports Server (NTRS)

    Banerdt, W. B.; Vidal, A.

    2001-01-01

    The role of water on Mars bears directly on investigations crossing a wide range of disciplines, including geomorphology, geochemistry, and biology. We have calculated the potential flow patterns of water using Mars Orbiter Laser Altimeter (MOLA) topographic data. Additional information is contained in the original extended abstract.

  19. 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

  20. 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.

  1. 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.

  2. Mars landing exploration mission

    NASA Astrophysics Data System (ADS)

    Suzaki, Megumi

    1991-07-01

    The overall concept for Mars observation missions and the systems to implement the missions are reviewed. Reviews are conducted on the following items: (1) profiles of the candidate missions; (2) aerodynamic capture deceleration estimates; (3) prospective Mars orbit decisions; (4) landing methods as the prerequisites for mission accomplishment; and (5) explorer systems to accomplish the missions. The major processes involved in the mission, from the launch to the beginning of observation of the surface, are outlined. Reviews of possible orbits taken by the explorer from Mars transfer orbit (Hohmann orbit) to Mars revolving orbit are presented. Additionally, the possible orbits for the landing vehicle from departing from the revolving orbit through landing are presented. Transportation and landing module design concepts concerning the structure, weight, and electric power balances of the explorer system are presented. Critical Mars mission technologies are cited as follows: (1) inter-planet navigation; (2) aerodynamic capture; (3) automatic and autonomous operation; and (4) landing technology.

  3. 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.

  4. Tests of crustal divergence models for Aphrodite Terra, Venus

    NASA Astrophysics Data System (ADS)

    Grimm, Robert E.; Solomon, Sean C.

    1989-09-01

    This paper discusses the characteristics of Aphrodite Terra, the highland region of Venus which is considered to be a likely site of mantle upwelling, active volcanism, and extensional tectonics, and examines the relation of these features to three alternative kinematic models for the interaction of mantle convection with the surface. These the 'vertical tectonics' model, in which little horizontal surface displacement results from mantle flow; the 'plate divergence' model, in which shear strain from large horizontal displacements is accommodated only in narrow zones of deformation; and the 'distributed deformation' model, in which strain from large horizontal motions is broadly accommodated. No convincing observational evidence was found to support the rigid-plate divergence, while the evidence of large-scale horizontal motions of Aphrodite argues against purely vertical tectonics. A model is proposed, involving a broad disruption of a thin lithosphere. In such a model, lineaments are considered to be surface manifestations of mantle convective flow.

  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. 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.

  7. 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.

  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. Four Views of Mars in Northern Summer

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Four faces of Mars as seen on March 30, 1997 are presented in this montage of NASA Hubble Space Telescope images. Proceeding in the order upper-left, upper-right, lower-left, lower-right, Mars has rotated about ninety degrees between each successive time step. For example the Tharsis volcanoes, which are seen (between 7:30 and 9 o'clock positions) in mid-morning in the UPPER-RIGHT view, are seen near the late afternoon edge of the planet (about 3 o'clock position) in the lower-left image. All of these color images are composed of individual red (673 nanometers), green (502 nm), and blue (410 nm) Planetary Camera exposures.

    Upper left: This view is centered on Ares Valles, where Pathfinder will land on July 4, 1997; the Valles Marineris canyon system stretches to the west across the lower left portion of the planet, while the bright, orangish desert of Arabia Planitia is to the east. The bright polar water-ice cap, surrounded by a dark ring of sand dunes, is obvious in the north; since it is northern summer and the pole is tilted toward us, the residual north polar cap is seen in its entirety in all four images. Acidalia Planitia, the prominent dark area fanning southward from the polar region, is thought to have a surface covered with dark sand. Numerous 'dark wind streaks' are visible to the south of Acidalia, resulting from wind-blown sand streaming out of the interiors of craters.

    Upper right: The Tharsis volcanos and associated clouds are prominent in the western half of this view. Olympus Mons, spanning 340 miles (550 km) across its base and reaching an elevation of 16 miles (25 km), extends through the cloud deck near the western limb, while (from the south) Arsia Mons, Pavonis Mons, and Ascraeus Mons are to the west of center. Valles Marineris stretches to the east, and the Pathfinder landing site is shrouded in clouds near the afternoon limb.

    Lower left: This relatively featureless sector of Mars stretches from the Elysium volcanic region in the

  10. 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

  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. 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).

  13. 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

  14. ExoMars 2016 arrives at Mars

    NASA Astrophysics Data System (ADS)

    Svedhem, Hakan; Vago, Jorge L.; ExoMars Team

    2016-10-01

    The Trace Gas Orbiter (TGO) and the Schiaparelli Entry, descent and landing Demonstrator Model (EDM) will arrive at Mars on 19 October 2016. The TGO and the EDM are part of the first step of the ExoMars Programme. They will be followed by a Rover and a long lived Surface Platform to be launched in 2020.The EDM is attached to the TGO for the full duration of the cruise to Mars and will be separated three days before arrival at Mars. After separation the TGO will perform a deflection manoeuvre and, on 19 October (during the EDM landing), enter into a highly elliptical near equatorial orbit. TGO will remain in this parking orbit until January 2017, when the orbital plane inclination will be changed to 74 degrees and aerobraking to the final 400 km near circular orbit will start. The final operational orbit is expected to be reached at the end of 2017.The TGO scientific payload consists of four instruments. These are: ACS and NOMAD, both infrared spectrometers for atmospheric measurements in solar occultation mode and in nadir mode, CASSIS, a multichannel camera with stereo imaging capability, and FREND, an epithermal neutron detector for search of subsurface hydrogen. The mass of the TGO is 3700 kg, including fuel. The EDM, with a mass of 600 kg, is mounted on top of the TGO as seen in its launch configuration. The main objective of the EDM is to demonstrate the capability of performing a safe entry, descent and landing on the surface, but it does carry a descent camera and a small battery powered meteorological package that may operate for a few days on the surface.The ExoMars programme is a joint activity by the European Space Agency(ESA) and ROSCOSMOS, Russia. ESA is providing the TGO spacecraft and Schiaparelli (EDM) and two of the TGO instruments and ROSCOSMOS is providing the launcher and the other two TGO instruments. After the arrival of the ExoMars 2020 mission at the surface of Mars, the TGO will handle the communication between the Earth and the Rover and

  15. Mars Aerobot Validation Program

    NASA Technical Reports Server (NTRS)

    Kerzhanovich, V. V.; Cutts, J.; Bachelder, A.; Cameron, J.; Patzold, J.; Quadrelli, M.; Yavrouian, A.; Cantrell, J.; Lachenmeier, T.; Smith, M.

    1999-01-01

    The Mars Balloon Validation Program (MABVAP) was initiated in August 1997 to develop and validate key technologies needed for aerobot missions on Mars. The major elements of the program are the development of balloons for flight on Mars, robust techniques for deployment and inflation and modeling and simulation of balloon flight paths. selection, development and tests of available balloon materials, design and fabrication of balloons (both superpressure and solar- heated), design and fabrication of deployment and inflation systems for aerial deployment, design and fabrication of avionics to control deployment/inflation process and to get telemetry and video data. Modeling of main processes during deployment and actual flight is also a part of MABVAP. In order to validate deployment and inflation, MABVAP applies experience from previous Mars balloon development or study activities the Russian-French Mars Aerostat Project (1988-1995), Mars Aerial Platform Study (1994) and Mars Aerobot/Balloon Study (1996). The program includes laboratory, wind tunnel, vacuum chamber tests of the system components and a number of tropospheric and stratospheric flight tests of deployment and inflation of lightfilm balloons in a simulated Martian environment.

  16. Global climatic change on Mars.

    PubMed

    Kargel, J S; Strom, R G

    1996-11-01

    The authors examine evidence from Mariner and Viking probes of the Martian environment to support theories of a global climate change on Mars. Similarities between some geographical features on Earth and Mars are used to suggest a warmer climate on Mars in the past. An overview of planned Mars exploration missions is included.

  17. 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.

  18. 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.

  19. 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.

  20. Mars surface transportation options

    NASA Technical Reports Server (NTRS)

    Leitner, Jeffrey M.; Alred, John W.

    1986-01-01

    As the number of scientific experiments for the surface of Mars grows, the need for effective surface transportation becomes critical. Because of the diversity of the experiments proposed, as well as the desire to explore Mars from the equator to the poles, the optimum surface vehicle configuration is not obvious. Five candidate vehicles are described, with an estimate of their size and performance. In order to maximize the success of a manned Mars mission, it appears that two vehicles should be designed for surface transportation: an advanced long-range rover, and a remotely-piloted airplane.

  1. Human exploration of Mars

    NASA Technical Reports Server (NTRS)

    Gwynne, Owen; Mckay, Chris; Zubrin, Robert

    1991-01-01

    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.

  2. 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.

  3. Exploring Mars in 1988

    NASA Astrophysics Data System (ADS)

    Beish, J. D.; Parker, D. C.

    1988-04-01

    During September 19-26, 1988, Mars will be 23.8 arcsec wide; this is fully 95 percent as large as Mars can ever possibly become, and only 1 arcsec smaller than it attained during the last very favorable apparition, in 1971. In the case of the 1988 apparition, Mars will be 20 deg higher in the sky than in either 1971 or 1986, offering observers in the Northern Hemisphere a much better view. The south polar cap is discussed as well as clouds and hazes, yellow dust storms, and seasonable trends.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Tempe Fossae, Mars: A planetary analogon to a terrestrial continental rift?

    NASA Astrophysics Data System (ADS)

    Hauber, Ernst; Kronberg, Peter

    2001-09-01

    Tempe Terra, the northeastern part of the Tharsis Region on Mars, is characterized by several extensional structures differing in style and age. The Tempe Fossae, a particularly well-developed system of graben striking N45°E, have been studied for the first time in detail on the basis of Viking Orbiter imagery and Mars Observer Laser Altimeter (MOLA) topographic data. The graben system appears to be unique in the whole region because of its extent, the remarkable width and depth of the graben, the varying graben pattern, and the associated volcanism. Single graben can be up to 35 km wide and 120 km long, while their depth can reach nearly 3000 m. They typically show an asymmetric architecture, often in halfgraben or step fault style. The graben system widens and changes its style along strike from NE to SW from a single, very deep, and narrow graben to a complex set of several shallower, sinuous graben and halfgraben. Crustal extension was measured in the northeastern part from the observable throw and amounts to 2.5-3.1 km. Volcanic structures can be found at several locations along the graben. In the SW the graben system seems to be connected with the Tempe Terra volcanic province marked by flood basalts and plains volcanism. Craters were counted on volcanic units unaffected by extensional tectonics. Crater statistics indicate an absolute crater model age for the upper end of the extensional deformation of ~3.5 Ga. The dimensions and the characteristics of the mapped graben system resemble those of terrestrial continental rifts, and a comparison between them and the Kenya Rift reveals striking similarities. Therefore the Tempe Fossae are interpreted as a Martian analog to a continental rift associated with an underlying mantle plume. This hypothesis seems to be supported by recent geophysical models based on topography and gravity data from Mars Global Surveyor which indicate regional uplift for Tempe Terra.

  10. 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...

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

    Atmospheric Science Data Center

    2014-05-15

    ... Terra Spacecraft Measures Height of California Rim Fire Smoke Plumes     View Larger Image ... This unique design allows it to measure the height of smoke plumes using stereoscopic techniques. This MISR image, acquired Aug. 23, ...

  12. 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.

  13. Provenance determination of Vinica terra cotta icons using self-organising maps.

    PubMed

    Tanevska, Vinka; Kuzmanovski, Igor; Grupce, Orhideja

    2007-07-01

    In the Vinica Fortress, Republic of Macedonia, 50 undamaged terra cotta icons and 100 fragments, all dated 6th-7th century, were found. In order to determine the provenance of these unique terra cotta icons, the mass fractions of 19 different chemical elements were previously determined in ten fragments of the terra cotta icons and thirty three samples of clays from eight different sites from the region. Due to the dimensionality and complexity of the experimental data, the archaeometric results were treated with self-organising maps (SOM). The results obtained using SOM were compared with the ones obtained using principal component analysis. Both chemometric methods revealed that Vinica terra cotta icons were made from clay from Grncarka, 2.5 km South-East from the Vinica Fortress.

  14. Telomeric repeat-containing RNA (TERRA) and telomerase are components of telomeres during mammalian gametogenesis.

    PubMed

    Reig-Viader, Rita; Vila-Cejudo, Marta; Vitelli, Valerio; Buscà, Rafael; Sabaté, Montserrat; Giulotto, Elena; Caldés, Montserrat Garcia; Ruiz-Herrera, Aurora

    2014-05-01

    Telomeres are ribonucleoprotein structures at the end of chromosomes composed of telomeric DNA, specific-binding proteins, and noncoding RNA (TERRA). Despite their importance in preventing chromosome instability, little is known about the cross talk between these three elements during the formation of the germ line. Here, we provide evidence that both TERRA and the telomerase enzymatic subunit (TERT) are components of telomeres in mammalian germ cells. We found that TERRA colocalizes with telomeres during mammalian meiosis and that its expression progressively increases during spermatogenesis until the beginning of spermiogenesis. While both TERRA levels and distribution would be regulated in a gender-specific manner, telomere-TERT colocalization appears to be regulated based on species-specific characteristics of the telomeric structure. Moreover, we found that TERT localization at telomeres is maintained throughout spermatogenesis as a structural component without affecting telomere elongation. Our results represent the first evidence of colocalization between telomerase and telomeres during mammalian gametogenesis.

  15. 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...

  16. 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...

  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. The Mars Observer Mission

    NASA Technical Reports Server (NTRS)

    Palluconi, F. D.

    1985-01-01

    The Mars Observer Mission is to be the first in a series of modest-cost inner-planet missions. Launch is planned for the August/September 1990 Mars opportunity with arrival at Mars one year later. The geoscience/climatology objectives are to be met during a mapping mission over the course of one Mars year (687 days). The mapping orbit will be near-polar (93 degree orbital inclination), sun-synchronous (2 PM sunward equator crossing), and near-circular (350 km orbit altitude, 116 minute period). The spacecraft, to be selected in late 1985, will be a modified version of an existing commercial design which, in the mapping orbit, will maintain a nadir orientation. Experiments and instruments will be selected through an Announcement of Opportunity (AO) process with release of the AO in April 1985, and selection in early 1986. A description of current planning for this mission, with emphasis on climatology, is presented here.

  19. Atmospheric Electricity on Mars

    NASA Astrophysics Data System (ADS)

    Delory, G.; Farrell, W.

    2011-10-01

    The atmosphere of Mars is one compelling example in our solar system that should possess active electrical processes, where dust storms are known to occur on local, regional, and global scales. Laboratory experiments and simulations all indicate that these events are expected to generate substantial quasi-static electric fields via triboelectric (i.e., frictional) charging, perhaps up to the breakdown potential of the Martian atmosphere. However current observations of potential electrical activity on Mars from both ground-based and orbital platforms have yielded conflicting results. If present, significant atmospheric electricity could be an important source of atmospheric chemistry on Mars, and thus impact our understanding of the evolution of the atmosphere and its past or present astrobiological potential. Here we review the current state of understanding regarding atmospheric electricity on Mars, and discuss its implications pending the results of future measurements.

  20. 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)

  1. 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).

  2. From Siberia to Mars

    PubMed

    McKay, C P; Friedmann, E I; Meyer, M A

    1991-01-01

    Because Mars is so similar to Earth, planetary scientists looking for answers to questions like these often use analogous environments on Earth to help them design future Mars missions. Such terrestrial sites, however remote, are still much more accessible than Mars. Field studies in such places give us a chance to test and refine instruments and procedures, develop overall concepts and collect baseline data to compare with actual results from Mars. Perhaps the best terrestrial analogue to the martian permafrost lies in northeastern Siberia. Freezing conditions have persisted here for over 3 million years. Although young by martian standards, these are among the oldest continuously frozen localities on Earth. They also hold something remarkable: not only organic residues, but also large numbers of viable bacteria (up to 100 million per gram of frozen soil), preserved for 3 million years in ice.

  3. 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

  4. 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.

  5. Mars' core and magnetism.

    PubMed

    Stevenson, D J

    2001-07-12

    The detection of strongly magnetized ancient crust on Mars is one of the most surprising outcomes of recent Mars exploration, and provides important insight about the history and nature of the martian core. The iron-rich core probably formed during the hot accretion of Mars approximately 4.5 billion years ago and subsequently cooled at a rate dictated by the overlying mantle. A core dynamo operated much like Earth's current dynamo, but was probably limited in duration to several hundred million years. The early demise of the dynamo could have arisen through a change in the cooling rate of the mantle, or even a switch in convective style that led to mantle heating. Presently, Mars probably has a liquid, conductive outer core and might have a solid inner core like Earth.

  6. 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

  7. 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.

  8. The atmosphere of Mars.

    NASA Astrophysics Data System (ADS)

    Irwin, P. G. J.; Calcutt, S. B.; Taylor, F. W.; McCleese, D. J.

    Mars, one of the most Earth-like of the planets, is today a cold, dry and barren world. However, there is good evidence that it may have been much warmer and wetter in the past and perhaps even supported life. The public interest aroused by these findings and by recent studies of `SNC' meteorites, believed to have come from Mars, with their claims of the evidence of ancient Martian life, has focused attention on the ambitious programme of Mars Exploration currently being undertaken by NASA and ESA and has provided additional impetus. Improved measurements of the conditions on Mars' surface and in its atmosphere are central to both agencies' plans, and current atmospheric missions are reviewed in this paper together with possible future designs.

  9. Bringing Life to Mars

    NASA Technical Reports Server (NTRS)

    McKay, C. P.

    1999-01-01

    A suitable long-term goal for human exploration of Mars is the determination of whether or not a self-sustainable bio-sphere could be constructed on Mars, a process called Terraforming. Preliminary considerations of the conditions on a habitable Mars suggest that there are two potentially habitable states: one -characterized by an atmosphere of 1-3 bars of CO2 - would be habitable for plants and microorganisms and another which would be habitable by humans. It may be possible to warm the planet by selective introduction of trace gases to enhance the greenhouse effect. Energy balance considerations suggest that warming Mars would take on the order of 100 years with a much longer time required to produce a breathable atmosphere.

  10. 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.

  11. Wind abrasion on Mars

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald

    1991-01-01

    Aeolian activity was predicted for Mars from earth based observations of changing surface patterns that were interpreted as dust storms. Mariner 9 images showed conclusive evidence for aeolian processes in the form of active dust storms and various aeolian landforms including dunes and yardangs. Windspeeds to initiate particle movement are an order of magnitude higher on Mars than on Earth because of the low atmospheric density on Mars. In order to determine rates of abrasion by wind blown particles, knowledge of three factors is required: (1) particle parameters such as numbers and velocities of windblown grains as functions of windspeeds at various heights above the surface; (2) the susceptibility to abrasion of various rocks and minerals; and (3) wind frequencies and speeds. For estimates appropriate to Mars, data for the first two parameters can be determined through lab and wind tunnel tests; data for the last two factors are available directly from the Viking Lander meteorology experiments for the two landing sites.

  12. The climate of Mars

    NASA Technical Reports Server (NTRS)

    Haberle, R. M.

    1986-01-01

    The composition of the primitive Martian atmosphere and its development into the present environment are described. The primitive atmosphere consisted of water vapor, carbon dioxide, and nitrogen released from rocks; the greenhouse effect which maintained the surface temperature above the frost point of water is examined. Volcanic activity reduced the greenhouse effect and along with CO2 removal from the atmosphere caused a lowering of the planet temperature. The global circulation patterns on earth and Mars are compared; the similarities in the circulation patterns and Mars' seasonal variations are studied. The carbon dioxide and water cycles on Mars are analyzed; the carbon dioxide cycle determines seasonal variations in surface pressure and the behavior of the water cycle. The behavior of the atmospheric dust and the relationship between the seasonal dust cycle and Hadley circulation are investigated. The periodic variations in the three orbital parameters of Mars, which affect the climate by changing the seasonal and latitudinal distribution of incoming solar energy are discussed

  13. 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.

  14. 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...

  15. 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 ...

  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. Geologic map of MTM -30247, -35247, and -40247 quadrangles, Reull Vallis region of Mars

    USGS Publications Warehouse

    Mest, Scott C.; Crown, David A.

    2014-01-01

    Mars Transverse Mercator (MTM) –30247, –35247, and –40247 quadrangles cover a portion of southern Hesperia Planum and the highlands of eastern Promethei Terra, east of the Hellas basin. The map area (lat 27.5–42.5° S., long 110–115° E.) consists of cratered ancient highland materials of moderate relief, isolated knobs and massifs of rugged mountainous materials, extensive tracts of plains, and surficial deposits. Waikato and Reull Valles extend through plains and highland terrains. Regional slopes are generally to the southwest toward the Hellas basin, but local slopes (for example, highlands to plains) dominate the landscape.

  18. 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.

  19. 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.

  20. Mars Observer Press Conference

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Footage shows Bob MacMillin, NASA's Public Information Office, as he introduces the Mars Observer Project Manager, Glen Cunningham. Glen is shown addressing the current status of the Mars Observer communication system, the inability of NASA to establish contact, and the action that is currently being taken to establish contact with the spacecraft. Glen is also seen answering questions from both the audience as well as other NASA Centers.

  1. North Polar Layers, Mars

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view shows the basal layers of Mars' north polar layered deposits. The floor of Chasma Boreale is at the bottom of the image. This is a sub-image of a larger view imaged by the High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter on Oct. 1, 2006. The resolution is 64 centimeters (25 inches) per pixel, and the scene is 568 meters (621 yards) wide.

  2. Mars Exploration Architecture

    NASA Technical Reports Server (NTRS)

    Jordan, James F.; Miller, Sylvia L.

    2000-01-01

    The architecture of NASA's program of robotic Mars exploration missions received an intense scrutiny during the summer months of 1998. We present here the results of that scrutiny, and describe a list of Mars exploration missions which are now being proposed by the nation's space agency. The heart of the new program architecture consists of missions which will return samples of Martian rocks and soil back to Earth for analysis. A primary scientific goal for these missions is to understand Mars as a possible abode of past or present life. The current level of sophistication for detecting markers of biological processes and fossil or extant life forms is much higher in Earth-based laboratories than possible with remotely deployed instrumentation, and will remain so for at least the next decade. Hence, bringing Martian samples back to Earth is considered the best way to search for the desired evidence. A Mars sample return mission takes approximately three years to complete. Transit from Earth to Mars requires almost a single year. After a lapse of time of almost a year at Mars, during which orbital and surface operations can take place, and the correct return launch energy constraints are met, a Mars-to-Earth return flight can be initiated. This return leg also takes approximately one year. Opportunities to launch these 3-year sample return missions occur about every 2 years. The figure depicts schedules for flights to and from Mars for Earth launches in 2003, 2005, 2007 and 2009. Transits for less than 180 deg flight angle, measured from the sun, and more than 180 deg are both shown.

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. 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.)

  8. Southern Mars: It's Spring!

    NASA Technical Reports Server (NTRS)

    1999-01-01

    August 2, 1999, marks the spring equinox for the martian southern hemisphere. It is also the start of autumn for regions north of the equator. Winter in the south has finally come to a close, and the seasonal frosts of the wintertime south polar cap are retreating. Small, local dust storms frequently occur along the margins of the polar cap, as the colder air blowing off the cap moves northward into warmer regions.

    The wide angle camera view of Mars shown here was obtained by the Mars Global Surveyor Mars Orbiter Camera in late July 1999, about 1 week before the start of southern spring. The frosty, retreating south polar cap (white) is seen in the lower quarter of the image, and wisps of dust storm clouds (grayish-orange in this view) occur just above the cap at the lower left. The southern most of the large environmental changes volcanoes, Arsia Mons, is seen at the upper left. Arsia Mons is about 350 kilometers(220 miles) across.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. 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.

  9. 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.

  10. Why exobiology on Mars?

    PubMed

    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 extraterrestrial 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 decelerating C-rich micro-meteorites. 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 photosynthesis, 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. A three-state model for the regulation of telomerase by TERRA and hnRNPA1.

    PubMed

    Redon, Sophie; Zemp, Ivo; Lingner, Joachim

    2013-10-01

    Telomeres, the physical ends of eukaryotic chromosomes, are transcribed into telomeric repeat-containing RNA (TERRA), a large non-coding RNA, which forms an integral part of telomeric heterochromatin. In vitro, naked TERRA molecules are efficient inhibitors of human telomerase, base-pairing via their 5'-UUAGGG-3' repeats with the template sequence of telomerase RNA, in addition to contacting the telomerase reverse transcriptase protein subunit. In vivo, however, TERRA-mediated inhibition of telomerase can be prevented by unknown mechanisms. Also, heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) has been implicated in telomere length control. In vivo, TERRA is partially associated with hnRNPA1, and hnRNPA1 is also detected at telomeres. We demonstrate that on binding of TERRA, hnRNPA1 can alleviate the TERRA-mediated inhibition of telomerase. However, when in excess over TERRA, hnRNPA1 becomes itself an inhibitor of telomere extension, on binding of the telomeric DNA substrate. Yet, hnRNPA1 has no notable direct effects on the telomerase catalysis. Our in vitro results suggest that TERRA-mediated telomerase inhibition may be prevented by hnRNPA1 in vivo. Telomere extension by telomerase may require balanced levels of TERRA and hnRNPA1 at telomeres. Thus, TERRA and hnRNPA1 can function as a bimolecular regulator to turn telomerase and the telomere on and off.

  16. From Soup to Nuts: How Terra has enabled the growth of NASA Earth science communication

    NASA Astrophysics Data System (ADS)

    Ward, K.; Carlowicz, M. J.; Allen, J.; Voiland, A.; Przyborski, P.

    2014-12-01

    The birth of NASA's Earth Observatory website in 1999 closely mirrored the launch of Terra and over the years its growth has paralleled that of the Earth Observing System (EOS) program. With the launch of Terra, NASA gained an extraordinary platform that not only promised new science capabilities but gave us the data and imagery for telling the stories behind the science. The Earth Observatory Group was founded to communicate these stories to the public. We will present how we have used the capabilities of all the Terra instruments over the past 15 years to expand the public's knowledge of NASA Earth science. The ever-increasing quantity and quality of Terra data, combined with technological improvements to data availability and services has allowed the Earth Observatory and, as a result, the greater science-aware media, to greatly expand the visibility of NASA data and imagery. We will offer thoughts on best practices in using these multi-faceted instruments for public communication and we will share how we have worked with Terra science teams and affiliated systems to see the potential stories in their data and the value of providing the data in a timely fashion. Terra has allowed us to tell the stories of our Earth today like never before.

  17. Telomeric repeat-containing RNA TERRA: a noncoding RNA connecting telomere biology to genome integrity.

    PubMed

    Cusanelli, Emilio; Chartrand, Pascal

    2015-01-01

    Telomeres are dynamic nucleoprotein structures that protect the ends of chromosomes from degradation and activation of DNA damage response. For this reason, telomeres are essential to genome integrity. Chromosome ends are enriched in heterochromatic marks and proper organization of telomeric chromatin is important to telomere stability. Despite their heterochromatic state, telomeres are transcribed giving rise to long noncoding RNAs (lncRNA) called TERRA (telomeric repeat-containing RNA). TERRA molecules play critical roles in telomere biology, including regulation of telomerase activity and heterochromatin formation at chromosome ends. Emerging evidence indicate that TERRA transcripts form DNA-RNA hybrids at chromosome ends which can promote homologous recombination among telomeres, delaying cellular senescence and sustaining genome instability. Intriguingly, TERRA RNA-telomeric DNA hybrids are involved in telomere length homeostasis of telomerase-negative cancer cells. Furthermore, TERRA transcripts play a role in the DNA damage response (DDR) triggered by dysfunctional telomeres. We discuss here recent developments on TERRA's role in telomere biology and genome integrity, and its implication in cancer.

  18. Structure of human telomeric RNA (TERRA): stacking of two G-quadruplex blocks in K(+) solution.

    PubMed

    Martadinata, Herry; Phan, Anh Tuân

    2013-04-01

    Telomeric repeat-containing RNAs (TERRA) are transcription products of the telomeres. Human TERRA sequences containing UUAGGG repeats can form parallel-stranded G-quadruplexes. The stacking interaction of such structures was shown to be important for ligand targeting and higher-order arrangement of G-quadruplexes in long TERRA sequences. Here we report on the first high-resolution structure of a stacked G-quadruplex formed by the 10-nucleotide human TERRA sequence r(GGGUUAGGGU) in potassium solution. This structure comprises two dimeric three-layer parallel-stranded G-quadruplex blocks, which stack on each other at their 5'-ends. The adenine in each UUA loop is nearly coplanar with the 5'-end G-tetrad forming an A·(G·G·G·G)·A hexad, thereby increasing the stacking contacts between the two blocks. Interestingly, this stacking and loop conformation is different from all structures previously reported for the free human TERRA but resembles the structure previously determined for a complex between a human TERRA sequence and an acridine ligand. This stacking conformation is a potential target for drugs that recognize or induce the stacking interface.

  19. Current studies on human papillomavirus in Saudi Arabia.

    PubMed

    Alhamlan, Fatimah Saeed; Al-Qahtani, Ahmed A; Al-Ahdal, Mohammed N

    2015-07-04

    Human papillomavirus (HPV) infection is a significant etiological factor and an important prognosticator in cervical cancer. Indeed, researchers worldwide have confirmed these roles for high-risk HVPs in over 70% of cervical cancer cases. According to the World Health Organization, approximately 561,200 new cancer cases (5.2% of all new cancers) are attributed to HPV infection. Over 120 types of HPV are classified further as either low-risk HPV (LR-HPV) or high-risk HPV (HR-HPV) based on their oncological potential of transforming cells. The LR-HPV types cause benign hyperproliferative lesions (i.e. genital warts) while the HR-HPV types are strongly associated with premalignant and malignant cervical lesions. Data on the prevalence of HPV, survival of infected patients, and mortality rate are scarce in Saudi Arabia. The unsubstantiated assumption of a low prevalence of HPV in Saudi Arabia has contributed to limiting HPV research in this conservative country. Therefore, the goal of this review is to shed light on the current HPV research being conducted and the prevalence of HPV in Saudi Arabia.

  20. Indoor Radon Concentration Levels in Najran Region, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Alyami, S. H.; Al-Ghamdi, S. S.; Baig, M. R.; Al-Garawi, M. S.

    2010-07-01

    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-3 and an average of 49±2 Bqm-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-3 set by the Environmental Protection Agency (EPA) of the USA

  1. 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

  2. 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

  3. Magnetically inferred basement structure in central Saudi Arabia

    USGS Publications Warehouse

    Johnson, P.R.; Stewart, I.C.F.

    1995-01-01

    A compilation of magnetic data acquired during the past three decades for a region in central Saudi Arabia where Precambrian basement is partly exposed on the Arabian shield and partly concealed by overlying Phanerozoic strata, shows a central sector of conspicuous N-S-trending anomalies, a heterogeneous western sector of short-wavelength, high-intensity anomalies, and an eastern sector of low- to moderate-intensity broad-wavelength anomalies. Anomalies in the western and central sectors correlate with Neoproterozoic metavolcanic, metasedimentary, and intrusive rocks of the Arabian shield and are interpreted as delineating extensions of shield-type rocks down-dip beneath Phanerozoic cover. These rocks constitute terranes making up part of a Neoproterozoic orogenic belt that underlies Northeast Africa and western Arabia and it is proposed that their magnetically indicated easternmost extent marks the concealed eastern edge of the orogenic belt in central Arabia. The flat magnetic signature of the eastern sector, not entirely accounted for as an effect of deep burial, may reflect the presence of a crustal block different in character to the terranes of the orogenic belt and, speculatively, may outline a continental block that, according to some tectonic models of the region, collided with the Neoproterozoic terranes and thereby caused their deformation and tectonic accretion.

  4. The demographic and clinical characteristics of leprosy in Saudi Arabia.

    PubMed

    Alotaibi, Mohammad H; Bahammam, Salman A; Ur Rahman, Saeed; Bahnassy, Ahmed A; Hassan, Imad S; Alothman, Adel F; Alkayal, Abdulkareem M

    2016-01-01

    Leprosy is a chronic disease caused by Mycobacterium leprae. Although the occurrence of leprosy has declined in Saudi Arabia, it has not yet been eradicated. To our knowledge, this descriptive retrospective study is the first to assess the clinical presentation of leprosy at the time of diagnosis in Saudi Arabia. All study subjects were leprosy patients admitted to Ibn Sina hospital, the only referral hospital for leprosy in Saudi Arabia, between January 2000 and May 2012. A total of 164 subjects, the majority of whom (65%) were between 21 and 50 years of age, were included, and the male-to-female ratio was 2.8:1. Of these 164 patients, 63% were Saudis, and 77% of all admitted patients were from the western region. Lepromatous leprosy was observed most frequently (33%), and 31% of cases had a positive history of close contact with leprosy. At the time of diagnosis, 84% of all subjects presented with skin manifestation. The prevalence of neurological deficit at the time of diagnosis was 87%. Erythema nodosum leprosum (E.N.L.) developed in only 10% of all subjects. Further studies are needed to determine the clinical characteristics pertaining to each type of leprosy in the region, and training courses in caring for and diagnosing patients with leprosy should be organized for health workers.

  5. Magnetically inferred basement structure in central Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Johnson, Peter R.; Stewart, Ian C. F.

    1995-05-01

    A compilation of magnetic data acquired during the past three decades for a region in central Saudi Arabia where Precambrian basement is partly exposed on the Arabian shield and partly concealed by overlying Phanerozoic strata, shows a central sector of conspicuous N-S-trending anomalies, a heterogeneous western sector of short-wavelength, high-intensity anomalies, and an eastern sector of low- to moderate-intensity broad-wavelength anomalies. Anomalies in the western and central sectors correlate with Neoproterozoic metavolcanic, metasedimentary, and intrusive rocks of the Arabian shield and are interpreted as delineating extensions of shield-type rocks down-dip beneath Phanerozoic cover. These rocks constitute terranes making up part of a Neoproterozoic orogenic belt that underlies Northeast Africa and western Arabia and it is proposed that their magnetically indicated easternmost extent marks the concealed eastern edge of the orogenic belt in central Arabia. The flat magnetic signature of the eastern sector, not entirely accounted for as an effect of deep burial, may reflect the presence of a crustal block different in character to the terranes of the orogenic belt and, speculatively, may outline a continental block that, according to some tectonic models of the region, collided with the Neoproterozoic terranes and thereby caused their deformation and tectonic accretion.

  6. Real Time Mars Approach Navigation Aided by the Mars Network

    NASA Technical Reports Server (NTRS)

    Ely, Todd A.; Duncan, Courtney; Lightsey, E. Glenn; Mogensen, Andreas

    2006-01-01

    A NASA Mars technology project is described that is building a prototype embedded real time Mars approach navigation capability which can be hosted on the Mars Network's Electra transceiver. The paper motivates the reason for doing real time Mars approach navigation via a set of analyses demonstrating its utility for enabling Mars pin-point landing (< 1-km landing error). The development approach, software design, and test results are discussed. Finally, the way forward towards a flight demonstration on the Mars Science Laboratory is presented.

  7. Real Time Mars Approach Navigation Aided by the Mars Network

    NASA Technical Reports Server (NTRS)

    Ely, Todd A.; Duncan, Courtney; Lightsey, E. Glenn; Mogensen, Andreas

    2006-01-01

    A NASA Mars technology project is described that is building a prototype embedded real time Mars approach navigation capability which can be hosted on the Mars Network's Electra transceiver. The paper motivates the reason for doing real time Mars approach navigation via a set of analyses demonstrating its utility for enabling Mars pin-point landing (less than 1-km landing error). The development approach, software design, and test results are discussed. Finally, the way forward towards a flight demonstration on the Mars Science Laboratory (MSL) is presented.

  8. 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.

  9. 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

  10. Mars at Ls 211o

    NASA Technical Reports Server (NTRS)

    2005-01-01

    31 May 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 211o during a previous Mars year. This month, Mars looks similar, as Ls 211o occurred in mid-May 2005. The picture shows the south polar region of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

    Season: Northern Autumn/Southern Spring

  11. 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.

  12. Mars at Ls 357o

    NASA Technical Reports Server (NTRS)

    2006-01-01

    31 January 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 357o during a previous Mars year. This month, Mars looks similar, as Ls 357o occurred in mid-January 2006. The picture shows the south polar region of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

    Season: Northern Winter/Southern Summer

  13. Mars at Ls 324o

    NASA Technical Reports Server (NTRS)

    2005-01-01

    29 November 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 324o during a previous Mars year. This month, Mars looks similar, as Ls 324o occurred in mid-November 2005. The picture shows the south polar region of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn.

    Season: Northern Winter/Southern Summer

  14. 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.

  15. Surface Current Measurements In Terra Nova Bay By Hf Radar

    NASA Astrophysics Data System (ADS)

    Flocco, D.; Falco, P.; Wadhams, P.; Spezie, G.

    We present the preliminary results of a field experiment carried out within frame- work of the CLIMA project of the Italian National Programme for Antarctic Research (PNRA) and in cooperation with the Scott Polar Research Institute of Cambridge. Dur- ing the second period (02/12/1999-23/01/2000) of the XV Italian expedition a coastal radar was used to characterize the current field in the area of Terra Nova Bay (TNB). One of the aims of the CLIMA (Climatic Long-term Interactions for the Mass balance in Antarctica) project is to determine the role of the polynya in the sea ice mass bal- ance, water structure and local climate. The OSCR-II experiment was planned in order to provide surface current measurements in the area of TNB polynya, one of the most important coastal polynya of the Ross Sea. OSCR (Ocean Surface Current Radar) is a shore based, remote sensing system designed to measure sea surface currents in coastal waters. Two radar sites (a master and a slave) provide with radial current mea- surements; data combined from both sites yield the total current vector. Unfortunately the master and slave stations did not work together throughout the whole period of the experiment. A description of the experiment and a discussion of the results, will be proposed.

  16. Variations in effective compensation depth across Aphrodite Terra, Venus

    SciTech Connect

    Herrick, R.R.; Hall, S.A. ); Bills, B.G.

    1989-06-01

    Aphrodite Terra is the largest elevated terrain on Venus and it serves as a focal point in current discussions of global tectonic style. Using the topography and gravity data acquired by the Pioneer Venus Orbiter (PVO) the authors have estimated an effective depth of Airy compensation for each of 75 orbital arcs that provide fairly uniform areal coverage of the entire province. The most pronounced pattern that emerges is a general increase in compensation depth to the east. The most rapid change occurs near 135{degree}; the average west of there is 70 km, while the average to the east is 230 km. Superimposed on this larger trend are five distinctive regional patterns, four well defined peaks and one interval of widely scattered and poorly constrained depths. The maxima in compensation depth are well correlated with regional topographic highs. While these observations are easily reconciled with the general notion that Aphrodite is a region of crustal divergence, the great depth of compensation is difficult to accord with the more specific suggestion that Aphrodite is a terrestrial type divergent plate margin. The alternative suggestion that Aphrodite, and the other equatorial highlands on Venus, are surface manifestations of hot upwelling mantle plumes is consistent both with the great depths of compensation and with the pattern of regional peaks and intervening troughs. The broader scale increase in effective depth of compensation from west to east is more enigmatic, but it might reflect an age progression of the plumes.

  17. 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.

  18. 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.

  19. Aoutomatic Oil Spill Detection Using TerraSAR-X Data

    NASA Astrophysics Data System (ADS)

    Zulipiye, Kaiyoumu; Balik Sanli, Fusun

    2016-07-01

    Oil release into the ocean may affect marine ecosystems and cause environmental pollution. Thus, oil spill detection and identification becomes critical important. Characterized by synoptic view over large regions, remote sensing has been proved to be a reliable tool for oil spill detection. Synthetic Aperture Radar (SAR) imagery shows returned signal that clearly distinguish oil from oil-free surface under optimal wind conditions, which makes it the most frequent used remote sensing technique in oil spill detection. Algorithms of automatic oil spill detection has already been developed for different SAR sensors, including RADARSAT and ENVISAT. In this study, we want to apply automatic oil spill detection algorithms on TerraSAR-X data which is previously developed for ASAR data. The applied methodology includes two steps as segmentation and classification. First segmentation algorithms compiled by C# have been applied under a Bayesian framework adopting a multi-level logistic. After segmentation different classification methods such as feature selection, filter, and embedded selection have been applied. As a result the used classifiers for oil spill detection will be compared, and the complete processing chain will be evaluated.

  20. Terra and Aqua: new data for epidemiology and public health.

    PubMed

    Tatem, Andrew J; Goetz, Scott J; Hay, Simon I

    2004-11-01

    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.