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Sample records for campanian-early maastrichtian orbital

  1. Upper Cretaceous woods from the Olmos Formation (late Campanian-early Maastrichtian), Coahuila, Mexico.

    PubMed

    Estrada-Ruiz, Emilio; Martínez-Cabrera, Hugo I; Cevallos-Ferriz, Sergio R S

    2010-07-01

    The Olmos Formation was part of a system of deltas that existed in the southern portion of the Western Interior of North America during the Campanian-Maastrichtian. The paleofloristic composition from the northern portions of the Epicontinental Sea is relatively well known, but less intensive exploration in the south has precluded more detailed floristic comparison across the entire latitudinal span of the Sea. The Olmos Formation flora, with more than 100 different leaf morphotypes so far recognized and several wood types, has the most diverse Cretaceous fossil plant assemblage in Mexico and represents a valuable opportunity for comparative studies. • The fossil woods here described were collected in the Coahuila State, Mexico. The samples were studied using standard thin section technique and identified by comparison with fossil and extant material. • We described four new genera (Olmosoxylon, cf. Lauraceae; Coahuiloxylon, ?Anacardiaceae, ?Burseraceae; Muzquizoxylon, Cornaceae; and Wheeleroxylon, Malvaceae s.l.) and three xylotypes of angiosperms. • Some of the genera present in the Olmos Formation such as Javelinoxylon and Metcalfeoxylon have been described from geologic units in the USA (San Juan Basin, New Mexico and Big Bend National Park, Texas), suggesting similarity in the taxonomic composition of the floras that inhabited southern portions of the western margin of the Campanian-Maastrichtian Epicontinental Sea. Other species, however, have only been reported for the Olmos Formation, indicating some degree of local floristic differentiation among the assemblages that inhabited the southern portion of the Western Interior.

  2. Does ice drive early Maastrichtian eustasy?

    USGS Publications Warehouse

    Miller, K.G.; Barrera, E.; Olsson, R.K.; Sugarman, P.J.; Savin, S.M.

    1999-01-01

    A large (30-40 m), rapid (???1 m.y.), earliest Maastrichtian sealevel drop inferred from New Jersey sequence stratigraphic records correlates with synchronous ??18O increases in deep-water benthic and low-latitude surface-dwellin planktonic foraminifera. The coincidence of these events argues for the development of a moderate-sized ice sheet during the early Maastrichtian.

  3. The biostratigraphy and paleogeography of Maastrichtian inoceramids

    NASA Technical Reports Server (NTRS)

    Macleod, K. G.; Huber, B. T.; Ward, P. D.

    1994-01-01

    The global distribution of Maastrichtian inoceramids is now known in enough detail that the patterns of disappearance can be used to place first-order constraints on paleoceanographic changes that may have occurred during that age. The Inoceramidae is an excellent group to focus on in a study of Maastrichtian events for the following reasons: (1) they were globally distributed in the early Maastrichtian; (2) they did not survive the age (i.e., they undergo change during the interval); and (3) they have left a rich microfossil and macrofossil record. Some inoceramids grew to be very large; however, even the largest often passively disaggregated and are preserved as hundreds of millions of characteristic, columnar, polygonal prisms of calcite approximately 100 microns across. This taphonomic process has greatly increased the inoceramid fossil record and provides a means of objectively estimating changes in their standing population. In addition, because these prisms commonly occur in Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) cores, it is relatively easy to generate a truly global database. The existing macrofossil record of inoceramids has less temporal and spacial resolution but greater taxonomic resolution than the microfossil record. In concert the microfossil and macrofossil records of inoceramids demonstrate that important changes occurred during the Maastrichtian. These changes are distinct from the KT boundary catastrophe but are part of the larger KT transition.

  4. Sedimentary provenance of Maastrichtian oil shales, Central Eastern Desert, Egypt

    NASA Astrophysics Data System (ADS)

    Fathy, Douaa; Wagreich, Michael; Mohamed, Ramadan S.; Zaki, Rafat

    2017-04-01

    Maastrichtian oil shales are distributed within the Central Eastern Desert in Egypt. In this study elemental geochemical data have been applied to investigate the probable provenance of the sedimentary detrital material of the Maastrichtian oil shale beds within the Duwi and the Dakhla formations. The Maastrichtian oil shales are characterized by the enrichment in Ca, P, Mo, Ni, Zn, U, Cr and Sr versus post-Archean Australian shales (PAAS). The chondrite-normalized patterns of the Maastrichtian oil shale samples are showing LREE enrichment, HREE depletion, slightly negative Eu anomaly, no obvious Ce anomaly and typical shale-like PAAS-normalized patterns. The total REE well correlated with Si, Al, Fe, K and Ti, suggesting that the REE of the Maastrichtian oil shales are derived from terrigenous source. Chemical weathering indices such as Chemical Index of Alteration (CIA), Chemical Proxy of Alteration (CPA) and Plagioclase Index of Alteration (PIA) indicate moderate to strong chemical weathering. We suggest that the Maastrichtian oil shale is mainly derived from first cycle rocks especially intermediate rocks without any significant inputs from recycled or mature sources. The proposed data illustrated the impact of the parent material composition on evolution of oil shale chemistry. Furthermore, the paleo-tectonic setting of the detrital source rocks for the Maastrichtian oil shale is probably related to Proterozoic continental island arcs

  5. Stratigraphic assessment of the Santonian to Maastrichtian Postalm section (northwestern Tethyan realm, Austria)

    NASA Astrophysics Data System (ADS)

    Wolfgring, Erik; Wagreich, Michael

    2014-05-01

    The Postalm section in the Northern Calcareous Alps (Austria) covers an almost continuous succession of Santonian to Maastrichtian hemipelagic to pelagic sediments. Our detailed stratigraphic study starts with an in-depth evaluation of the R. calcarata total range zone. The implementation of a cyclostratigraphic model was followed by a high resolution assessment of foraminifera and nannoplankton communities of this interval (Wagreich et al., 2012). In the aim to expand the cyclostratigraphic framework for the Upper Cretaceous, a biostratigraphic sampling of the entire succession at Postalm was conducted. As cyclic sedimentation of marls and marly limestones prevails throughout the section, over 300 samples have been taken bed-by-bed. Foraminifera data suggest the outcrop covers an interval ranging from the uppermost Santonian Dicarinella asymetrica to the Maastrichtian Gansserina gansseri Zone (nannofossil zones CC17 to CC22). The lowermost part of the section displays a comparatively shallow shelf environment yielding high percentage of benthic foraminifera with a highly diverse community. However, we can observe a distinct deepening in the basal Campanian and towards the Maastrichtian. Stratigraphically younger parts (i.e. Upper Campanian and Maastrichtian) of the section are displaying a deeper palaeoenvironment. In this pelagic environment foraminifera packstones with marl intercalations dominate the lithology. The state of preservation of microfossils has to be considered as moderate to poor. Evidence for frequent turbidite events in the uppermost (Maastrichtian) part of the section was recorded. As isotope records of the previousely investigated calcarata interval at Postalm correlate well to other Campanian sections, we are confident to find a valuable proxy in the data from other subsections of this outcrop as well. The cyclostratigraphic evaluation of sedimentation cycles in combination with biostratigraphic data sheds light upon the duration of planktic

  6. Stratigraphy of Maastrichtian sediments, southeastern N. C

    SciTech Connect

    Laws, R.A.; Dockal, J.A.; Harris, W.B. . Dept. of Earth Sciences)

    1994-03-01

    The Martin-Marietta limestone quarry at Castle Hayne and a series of core-holes in northern New Hanover County expose a moderate to dark gray silty, dolomitic very fine to fine grained quartz sand that is paraconformable with the underlying Rocky Point member of the Peedee Formation and disconformable with the overlying Eocene Castle Hayne Limestone. The unit which has a maximum thickness of about 2 m is absent to the north and west, thickens to the south and east and is exposed on the east bank of the Northeast Cape Fear River at Hilton Park, Wilmington, NC. All traces of original bedding have been removed by extensive bioturbation. Thin sections indicate that the unit ranges from a very fine to fine argillaceous-dolomitic quartz sand to a sandy dolomitic clay. A moderately well-preserved, low diversity calcareous nannofossil assemblage including Arkhangelskiella cymbiformis, Ceratolithodes acculeus, Eiffellithus eximius, Microrhabdulus attenuatus, M. decoratus, Micula staurophora, Prediscosphaera cretacea, Quadrum trifdum, and Wartznauria biporta, indicates correlation to the Quadrum trifdum Zone (CC22b to CC23b) of latest Campanian to earliest Maastrichtian age. This correlation suggests that the unit is a lithofacies of the Rocky Point Member. Stable isotopic analyses of the dolomite indicates that [delta][sup 18]O varies between +2.16[per thousand] to +3.73[per thousand] and [delta][sup 13]C between [minus]0.43[per thousand] to +0.62[per thousand], and suggests two mechanisms to explain the origin of the dolomite: (1) dolomitization of calcite/aragonite bioclasts under marine aqueous conditions or (2) inorganic dolomite precipitation under anoxic marine aqueous conditions with light carbon enrichment.

  7. The Campanian - Maastrichtian (Late Cretaceous) climate transition linked to a global carbon cycle perturbation

    NASA Astrophysics Data System (ADS)

    Voigt, S.; Friedrich, O.; Gale, A. S.

    2009-04-01

    The Late Cretaceous was a period of long-term climate cooling succeeding the extreme warmth of the mid-Cretaceous greenhouse world. The cooling is mainly considered as a result of changes in ocean circulation due to plate movements resulting in progressive deep-water exchange between the deep oceanic basins and a parallel drop in atmospheric carbon dioxide concentrations. In Campanian - Maastrichtian times, pronounced climate cooling is documented between 71 - 69 Ma, when distinct changes in foraminiferal oxygen and carbon isotope data at a global scale indicate substantial deep-water cooling and reduced rates of organic carbon burial. The causal mechanisms of this cooling period, however, are poorly understood to date. While some authors suggest mainly oceanographic changes, others supposed an ephemeral glaciation related to a eustatic sea-level fall. Mainly, the relative timing of oceanic oxygen and carbon isotope changes to eustatic sea-level changes is not proven yet. Likewise, the influence of plate tectonic changes as the opening of gateways or the subduction of mid-ocean ridges and/or of orbital forcing is poorly understood. A principle objection beside the sparse available data is the low temporal resolution of biostratigraphic zonations. Here, we present carbon isotope stratigraphies from Campanian-Maastrichtian Boundary sites in the Boreal and Tethyan shelf seas of Europe and from Shatsky Rise in the tropical Pacific in order to improve the resolution of stratigraphic correlation. Prominent features at that time are two negative carbon isotope excursions (CIEs) in the late Campanian and earliest Maastrichtian, which are well documented in the Lägerdorf-Kronsmoor section in N-Germany and the Campanian-Maastrichtian Boundary Stratotype at Tercis in SW France. These new carbon isotope records correlate well with the carbon isotope reference curve from the English Chalk (Jarvis et al., 2002, 2006). The new carbon isotope record at Site 305 in the tropical

  8. Global climate change and planktic foraminiferal response in the Maastrichtian

    NASA Astrophysics Data System (ADS)

    Abramovich, Sigal; Yovel-Corem, Shlomit; Almogi-Labin, Ahuva; Benjamini, Chaim

    2010-04-01

    The lengthy warm, stable climate of the Cretaceous terminated in the Campanian with a cooling trend, interrupted in the early and latest Maastrichtian by two events of global warming, at ˜70-68 Ma and at 65.78-65.57 Ma. These climatic oscillations had a profound effect on pelagic ecosystems, especially on planktic foraminiferal populations. Here we compare biotic responses in the tropical-subtropical (Tethyan) open ocean and mesotrophic (Zin Valley, Israel) and oligotrophic (Tunisia) slopes, which correlate directly with global warming and cooling. The two warming events coincide with blooms of Guembelitria, an extreme opportunist genus best known as the main survivor of the Cretaceous-Paleogene (K-Pg) catastrophe. In the Maastrichtian, Guembelitria bloomed in the uppermost surface water above shelf and slope environments but failed to reach the open ocean as it did at K-Pg. The coldest interval of the late Maastrichtian (˜68-65.78 Ma) is marked by an acme of the otherwise rare species Gansserina gansseri, a deep-dwelling keeled globotruncanid. The G. gansseri acme event can be traced from the deep ocean even onto the Tethyan slope, marking copious production and circulation of cold intermediate water. This acme is abruptly terminated by extinction of the species, a dramatic reversal attributed to a short-term global warming episode. This extinction corresponds precisely with the second bloom of Guembelitria that began ˜300 kyr prior to the K-Pg event. The antithetical relationship between blooming of Guembelitria and the G. gansseri acme reflects planktic foraminiferal sensitivity to warm-cool-warm-cool climatic oscillations marking the end of the Cretaceous.

  9. Maastrichtian ammonites from the Hornerstown Formation in New Jersey

    USGS Publications Warehouse

    Kennedy, W.J.; Cobban, W.A.

    1996-01-01

    The base of the Paleocene Hornerstown Formation at the Inversand pit and certain other localities in New Jersey yields a diverse phosphatised fauna of Maastrichtian age, including the ammonites Pachydsicus (Neodesmoceras) mokotibensis Collignon, 1952, Sphenodiscus lobatus (Tuomey, 1854), Baculites spp., and Eubaculites carinatus (Morton, 1834). S. lobatus is known from the older Red Bank Sand and Tinton Sand in New Jersey; the other species are known only from the basal Hornerstown. Occurrences at the Inversand pit are regarded as either reworked or remainie, although details of Cretaceous/Paleocene boundary events have been destroyed by pervasive burrowing that pipes the Hornerstown down into the underlying Navesink Formation.

  10. Orbital

    NASA Astrophysics Data System (ADS)

    Hanson, Robert M.

    2003-06-01

    ORBITAL requires the following software, which is available for free download from the Internet: Netscape Navigator, version 4.75 or higher, or Microsoft Internet Explorer, version 5.0 or higher; Chime Plug-in, version compatible with your OS and browser (available from MDL).

  11. The Maastrichtian flora of the Amaam Lagoon area (Northeastern Russia)

    NASA Astrophysics Data System (ADS)

    Moiseeva, M. G.

    2012-12-01

    The Maastrichtian Koryak flora from the Amaam Lagoon area is comprehensively studied with reference to available data on the stratigraphy of the study area and age assessment of the flora-bearing deposits. In the Koryak flora 32 species of plant fossils are identified and systematically described in the work. The established traits of the Koryak floristic assemblage are used to correlate it with the other assemblages close in age from different localities of Northeastern RNortheastern Russiaussia and Alaska. The results of correlation and taxonomic revision of plant fossils from the upper part of the Prince Creek Formation, Northern Alaska show that in the Anadyr-Koryak and Northern Alaska circum-Pacific regions the Koryak stage of flora development and the respective phytostratigraphic horizon (upper Maastrichtian-Selandian), of key significance for interregional correlation of continental deposits, are distinguishable. Floristic changes recorded in the northern circum-Pacific regions across the Cretaceous-Paleogene boundary suggest that the evolution of vegetation was gradual, controlled by climatic change, evolutionary factors and plant migration. These results are inconsistent with the postulated global significance of the ecological crisis at that time.

  12. Late Maastrichtian and Danian ostracode faunas from northern Alaska: reconstructions of environment and paleogeography

    USGS Publications Warehouse

    Brouwers, E.M.; De Deckker, P.

    1993-01-01

    A 300-m sequence of well-exposed fossiliferous outcrops in bluffs along the Colville River, northern Aslaska, has yielded diverse, well-preserved Maastrichtian and Danian ostracode assemblages. The Maastrichtian strata are nonmarine flood-plain deposits and contain diverse terrestrial and aquatic fossils. The Danian strata are predominantly marginal-marine and shallow-marine and include an abundant and diverse invertebrate fauna. During the Maastrichtian and early Palaeocene, polar terrestrial and marine assemblages consisted predominantly of endemic organisms that were adapted to the cool temperatures, seasonal low light conditions, and geographic isolation characteristic of northern high-latitude environments. -from Authors

  13. Campanian-Maastrichtian radiolarians from the Malokuril'skaya Formation, the Shikotan Island

    NASA Astrophysics Data System (ADS)

    Palechek, T. N.; Terekhov, E. P.; Mozherovskii, A. V.

    2008-12-01

    The results of radiolarian analysis confirm the Campanian-Maastrichtian age of the Malokuril’skaya Formation in the Shikotan Island. The Campanian-Maastrichtian age of the formation is implied simultaneously by radiolarians and inoceramids. The studied Campanian and Campanian-Maastrichtian radiolarian assemblages include abundant specimens representing genus Prunobrachium, characteristic of which was bipolar distribution in cold-water to temperate basins. The new occurrence site of prunobrachids is established at the latitude of 43°N, the Far East of Russia.

  14. Late Cretaceous base level lowering in Campanian and Maastrichtian depositional sequences, Kure Beach, North Carolina

    USGS Publications Warehouse

    Harris, W.B.; ,

    2006-01-01

    Campanian through Maastrichtian mixed carbonate and siliciclastic sediments in a 422 m continuous core drilled at Kure Beach, NC provide a record of sea-level change. Based on lithology and stratigraphy, depositional sequences are defined, and calcareous nannofossil zones and 87Sr/86Sr ratios and corresponding ages using the LOWESS Table determined. Campanian and Maastrichtian sediments comprise six depositional sequences. The oldest is Tar Heel 1 and contains calcareous nannofossils that indicate assignment to the upper part of Zones CC18a, CC18c and the lower part of CC19. 87Sr/86 Sr ratios indicate ages from 83.2 to 80.0 Ma or lower Campanian. Tar Heel II contains calcareous nannofossils that indicate assignment to the upper part of Zone CC 19 and CC20. 87Sr/86Sr ratios indicate ages from 78.0 to 76.3 Ma or middle Campanian. Donoho Creek I and II are thin and contain calcareous nannofossils referable to upper Zone CC21 and Zone CC22, and to CC23, respectively. The top of Donoho Creek II marks the Campanian-Maastrichtian boundary. Donoho Creek I 87Sr/86Sr ratios cluster into two groups, and provide ages from 78.0 to 76.2 Ma and 73.7 to 72.3 Ma, respectively. 87Sr/86Sr ratios in Donoho Creek II indicate ages from 71.4 to 69.6 Ma. Two Maastrichtian sequences are present; the lowermost Peedee I contains calcareous nannofossils that place it in Zones CC25a and CC25b. 87Sr/86Sr r ratios indicate an age from 69.3 to 66.9 Ma or late Maastrichtian. Peedee II is assigned to calcareous nannofossil Zone CC26a. 87Sr/86Sr ratios indicate ages from 66.4 to 65.2 Ma or late Maastrichtian. The four Campanian sequences correlate to three depositional sequences in New Jersey; the sequence boundary between upper Campanian Donoho Creek I and Donoho Creek II is not recognized in New Jersey. This boundary is interpreted to result from Gulf Stream impingement and subsequent erosion on the outer shelf. The two Maastrichtian sequences recognized in the Kure Beach core correlate to the two

  15. Calcareous nannofossil evidence for the existence of the Gulf Stream during the late Maastrichtian

    USGS Publications Warehouse

    Watkins, D.K.; ,

    2005-01-01

    Upper Maastrichtian calcareous nannofossil assemblages, from eight cores on the South Carolina Coastal Plain (onshore set) and three deep sea drilling sites from the continental slope and abyssal hills (offshore set), were analyzed by correlation and principal component analysis to examine the ancient surface water thermal structure. In addition, a temperature index derived from independently published paleobiogeographic information was applied to the sample data. All three methods indicate a strong separation of the samples into onshore and offshore sets, with the offshore data set exhibiting significantly warmer paleotemperatures. The great disparity between these two sample sets indicates that there was a strong thermal contrast between the onshore and offshore surface water masses that persisted throughout the late Maastrichtian despite evident shortterm changes in fertility, productivity, and community structure. This suggests the Gulf Stream was present as a major oceanographic feature during the late Maastrichtian. Copyright 2005 by the American Geophysical Union.

  16. Maastrichtian sedimentation and palaeoenvironments of the Saratov Volga region

    NASA Astrophysics Data System (ADS)

    Iakovishina, Elena; Blinova, Irina; Kopaevich, Ludmila; Vishnevskaya, Valentina; Bordunov, Sergey

    2016-04-01

    The Saratov Volga region was a shallow-marine epicontinental basin North-Eastern shelf zone of the Tethys Ocean in the Maastrichtian. The basis for the modeling conditions of sedimentation was the detection mineral composition of rocks, as well as the contents of various chemical elements in rocks in three reference sections: Lower Bannovka, quarries "Bolshevik" and "Kommunar". Rocks of quarries "Bolshevik" and "Kommunar" characterized by quartz-calcite mineral association. The main rock-forming mineral is calcite, small amounts in rocks contain quartz. Other mineral composition characterized section Lower Bannovka. At the base of the section in the rock marked the presence of the opal. The source of silica are radiolarians. Favorable conditions for the existence of which is cold deep water enriched with SiO2. Above the section marked authigenic glauconite, which are confined to zones of skip in sedimentation.Further up begins to dominate the accumulation of calcite with rich bentic foraminifera. Clay minerals in rocks of the section Lower Bannovka presented montmorillonite and illite. The relationship of chemical elements and their alkali modules allow to detail the conditions of sedimentation. The ratio of Fe/Mn in them varies from 44 to 5729. Higher values are characteristic of glauconite sandstones. Up the section marked decrease in the Ti/Zr, indicating that the increase in the distance from the source area to the place of deposition. The similarity values of the ratio Ti/Zr samples indicates a community source area. Sedimentation Model revealed the impact of the PreUral strait connecting Tethys and Paleoarktic. Through the Strait of deep cold water saturated with SiO2, penetrated into the of the Saratov Volga region, were accumulated clay. The closing of the PreUral Strait changed the conditions of sedimentation, the associated fall in sea levels due to global cooling reflected in the crisis of radiolarians, increase in the number of glauconite. Subsequent

  17. Maastrichtian ammonites chiefly from the Prairie Bluff Chalk in Alabama and Mississippi

    USGS Publications Warehouse

    Cobban, W.A.; Kennedy, W.J.

    1995-01-01

    The Prairie Bluff Chalk of Alabama and Mississippi yields a diverse ammonite fauna of Maastrichtian age. Twenty-eight species, of which three are new, are recorded. The bulk of the fauna can be referred to a Discoscaphites conradi assemblage zone, but some elements in the fauna are significantly older. -Authors

  18. Late Cretaceous (late Campanian-Maastrichtian) sea-surface temperature record of the Boreal Chalk Sea

    NASA Astrophysics Data System (ADS)

    Thibault, Nicolas; Harlou, Rikke; Schovsbo, Niels H.; Stemmerik, Lars; Surlyk, Finn

    2016-02-01

    The last 8 Myr of the Cretaceous greenhouse interval were characterized by a progressive global cooling with superimposed cool/warm fluctuations. The mechanisms responsible for these climatic fluctuations remain a source of debate that can only be resolved through multi-disciplinary studies and better time constraints. For the first time, we present a record of very high-resolution (ca. 4.5 kyr) sea-surface temperature (SST) changes from the Boreal epicontinental Chalk Sea (Stevns-1 core, Denmark), tied to an astronomical timescale of the late Campanian-Maastrichtian (74 to 66 Ma). Well-preserved bulk stable isotope trends and calcareous nannofossil palaeoecological patterns from the fully cored Stevns-1 borehole show marked changes in SSTs. These variations correlate with deep-water records of climate change from the tropical South Atlantic and Pacific oceans but differ greatly from the climate variations of the North Atlantic. We demonstrate that the onset and end of the early Maastrichtian cooling and of the large negative Campanian-Maastrichtian boundary carbon isotope excursion are coincident in the Chalk Sea. The direct link between SSTs and δ13C variations in the Chalk Sea reassesses long-term glacio-eustasy as the potential driver of carbon isotope and climatic variations in the Maastrichtian.

  19. Late Cretaceous (Late Campanian-Maastrichtian) sea surface temperature record of the Boreal Chalk Sea

    NASA Astrophysics Data System (ADS)

    Thibault, N.; Harlou, R.; Schovsbo, N. H.; Stemmerik, L.; Surlyk, F.

    2015-11-01

    The last 8 Myr of the Cretaceous greenhouse interval were characterized by a progressive global cooling with superimposed cool/warm fluctuations. The mechanisms responsible for these climatic fluctuations remain a source of debate that can only be resolved through multi-disciplinary studies and better time constraints. For the first time, we present a record of very high-resolution (ca. 4.5 kyr) sea-surface temperature (SST) changes from the Boreal epicontinental Chalk Sea (Stevns-1 core, Denmark), tied to an astronomical time scale of the late Campanian-Maastrichtian (74 to 66 Myr). Well-preserved bulk stable isotope trends and calcareous nannofossil palaeoecological patterns from the fully cored Stevns-1 borehole show marked changes in SSTs. These variations correlate with deep-water records of climate change from the tropical South Atlantic and Pacific oceans but differ greatly from the climate variations of the North Atlantic. We demonstrate that the onset and end of the early Maastrichtian cooling and of the large negative Campanian-Maastrichtian boundary carbon isotope excursion are coincident in the Chalk Sea. The direct link between SSTs and δ13C variations in the Chalk Sea reassesses long-term glacio-eustasy as the potential driver of carbon isotope and climatic variations in the Maastrichtian.

  20. A New Crocodylian from the Late Maastrichtian of Spain: Implications for the Initial Radiation of Crocodyloids

    PubMed Central

    Puértolas, Eduardo; Canudo, José I.; Cruzado-Caballero, Penélope

    2011-01-01

    Background The earliest crocodylians are known primarily from the Late Cretaceous of North America and Europe. The representatives of Gavialoidea and Alligatoroidea are known in the Late Cretaceous of both continents, yet the biogeographic origins of Crocodyloidea are poorly understood. Up to now, only one representative of this clade has been known from the Late Cretaceous, the basal crocodyloid Prodiplocynodon from the Maastrichtian of North America. Methodology/Principal Findings The fossil studied is a skull collected from sandstones in the lower part of the Tremp Formation, in Chron C30n, dated at −67.6 to 65.5 Ma (late Maastrichtian), in Arén (Huesca, Spain). It is located in a continuous section that contains the K/P boundary, in which the dinosaur faunas closest to the K/P boundary in Europe have been described, including Arenysaurus ardevoli and Blasisaurus canudoi. Phylogenetic analysis places the new taxon, Arenysuchus gascabadiolorum, at the base of Crocodyloidea. Conclusions/Significance The new taxon is the oldest crocodyloid representative in Eurasia. Crocodyloidea had previously only been known from the Palaeogene onwards in this part of Laurasia. Phylogenetically, Arenysuchus gascabadiolorum is situated at the base of the first radiation of crocodyloids that occurred in the late Maastrichtian, shedding light on this part of the cladogram. The presence of basal crocodyloids at the end of the Cretaceous both in North America and Europe provides new evidence of the faunal exchange via the Thulean Land Bridge during the Maastrichtian. PMID:21687705

  1. Morphology and size variation of a portunoid crab from the Maastrichtian of the Americas

    NASA Astrophysics Data System (ADS)

    Vega, Francisco J.; Phillips, George E.; Nyborg, Torrey; Flores-Ventura, José; Clements, Don; Espinosa, Belinda; Solís-Pichardo, Gabriela

    2013-11-01

    The portunoid crab OphthalmoplaxRathbun, 1935, is known from late Cretaceous deposits of Africa and the Americas. A review of 76 specimens from many localities in North and South America reveals that the genus is represented by only two species - one in Africa (recently described) and the other in the Americas. Ophthalmoplax brasiliana (Maury, 1930) was distributed along the Atlantic and Gulf coasts of the Americas throughout the Maastrichtian - from Brazil to North Carolina. In early Maastrichtian deposits of North America (˜69.0 Ma), the species is represented by local populations of medium-sized individuals, and by the late Maastrichtian (˜67.0 Ma), populations of larger individuals became abundant. This size increase may be related to a decrease in ocean water temperatures. Populations of medium-sized individuals are found again in the latest Maastrichtian (˜66.2 Ma), below strata with ejecta deposits in Coahuila, Mexico, and in the uppermost Owl Creek Formation, Mississippi. This size decrease is possibly linked to an increase in seawater temperature occurring just below the K/P boundary, when Ophthalmoplax became extinct.

  2. Upper Campanian-lower Maastrichtian planktonic foraminifers from Govorov Guyot (Magellan Seamounts, Pacific Ocean)

    NASA Astrophysics Data System (ADS)

    Korchagin, O. A.; Pletnev, S. P.; Mel'Nikov, M. E.

    2011-06-01

    The planktonic foraminiferal assemblage from foraminiferal limestone (ooze) dredged from the summit of one of guyots in the Magellan Seamount system of the Pacific is dominated by one-keeled species belonging to the genus Globotruncanita. The taxonomic composition of the assemblage correlates host rocks with the upper Campanian-lower Maastrichtian. One species and one subspecies are described as new taxa.

  3. Trends in late Maastrichtian calcareous nannofossil distribution patterns, Western North Atlantic margin

    USGS Publications Warehouse

    ,

    2002-01-01

    First and last occurrences of several Maastrichtian calcareous nannofossil species are shown to be diachronous across paleodepth and paleoenvironment using the graphic correlation method. Calcareous nannofossil assemblages examined from eleven cores from a deep- to shallow-water transect along the eastern United States Atlantic margin document that the first occurrence of Micula murus (Martini 1961) Bukry 1973 is diachronous, appearing 2.0 million years earlier in open ocean sites than in shallow marine sites. The first occurrence (FO) of Lithraphidites kennethii Perch-Nielsen 1984 is also nonsynchronous, appearing in the deep ocean before its FO in neritic waters. The last occurrence (LO) of L. praequadratus Roth 1978 is diachronous across paleodepth, going locally extinct first in deeper water. The LO of Watznaueria bybelliae Self-Trail 1999 is also diachronous, going locally extinct first in shallow-water settings. Ceratolithoides amplector Burnett 1997, C. pricei Burnett 1997, C. self-trailiae Burnett 1997, C. ultimus Burnett 1997, Cribrocorona gallica (Stradner 1963) Perch-Nielsen 1973. Micula praemurus (Bukry 1973) Stradner and Steinmetz 1984, Pseudomicula quadratus Perch-Nielsen et al. 1978, and Semihololithus spp. are present consistently in common to frequent abundances in ODP holes 1050C and 1052E on the Blake Nose, but they are rare or absent from neritic sections in Coastal Plain cores. It is apparent that these species flourished in an open ocean setting, suggesting that differences in assemblage abundance and diversity between deep ocean and nearshore areas were controlled by paleoceanographic factors. These species are not used for biostratigraphy, but may be useful indicators of open ocean conditions. The line of correlation (LOC) for nine Coastal Plain cores clearly defines the Cretaceous-Tertiary (K/T) boundary unconformity at the top of the Maastrichtian section (Peedee Formation) and the Campanian-Maastrichtian (C/M) unconformity at the base of

  4. Changes in floral diversities, floral turnover rates, and climates in Campanian and Maastrichtian time, North Slope of Alaska

    USGS Publications Warehouse

    Frederiksen, N.O.

    1989-01-01

    One-hundred-and-ten angiosperm pollen taxa have been found in upper Campanian to Masstrichtian rocks of the Colville River region, North Slope of Alaska. These are the highest paleolatitude Campanian and Maastrichtian floras known from North America. Total angiosperm pollen diversity rose during the Campanian and declined toward the end of the Maastrichtian. However, anemophilous porate pollen of the Betulaceae-Myricaceae-Ulmaceae complex increased gradually in diversity during the late Campanian and Maastrichtian and into the Paleocene. Turnover of angiosperm taxa was active throughout most of late Campanian and Maastrichtian time; rapid turnover affected mainly the taxa of zoophilous herbs, representing an bundant but ecologically subordinate element of the vegetation. Last appearances of pollen taxa during the late Campanian and Maastrichtian probably represented mainly extinctions rather than emigrations; end- Cretaceous angiosperm extinctions in the North American Arctic began well before the Cretaceous-Tertiary boundary event. The last appearances in the late Maastrichtian took place in bursts; they appear to represent stepwise rather than gradual events, which may indicate the existence of pulses of climatic change particularly in late Maastrichtian time. ?? 1989.

  5. Campanian to Maastrichtian pollen biostratigraphy and floral turnover rates, Colville River region, north slope of Alaska

    SciTech Connect

    Frederiksen, N.O.; Schindler, K.S.

    1987-05-01

    This study is based on occurrence data for 104 angiosperm pollen taxa from 83 pollen-bearing outcrop and core samples taken along the Colville River and stratigraphically distributed from the base of the Sentinel Hill Member of the Schrader Bluff Formation to the top of the Cretaceous section. Many of the pollen taxa are highly useful for intraregional correlations because they have remarkably short stratigraphic ranges and are consistently present within these ranges. Important similarities are present between North Slope pollen assemblages and those of western Canada, Siberia, and China. The Campanian-Maastrichtian boundary is approximately marked by the range bases of Wodehouseia edmontonicola and Senipites drummhellerensis and is nearly as far south (downsection) as Sentinel Hill core test 1. Based on pollen correlations with Alberta, the marine beds at Ocean Point are probably within the middle part of the Maastrichtian, and strata north of Ocean Point that contain Aquilapollenites conatus are uppermost Maastrichtian. Thus, if the Cretaceous-Tertiary boundary in the study area is represented by an unconformity as their data suggest, the lowermost Paleocene is missing, not the uppermost Cretaceous. Maximum diversities of species of the stratigraphically significant Triprojectacites and Expressipollis groups are in the upper Campanian. Major turnovers of angiosperm taxa occurred late in the Campanian and in the Maastrichtian, but high rates of first appearances coincided with high rates of last appearances. Thus, once a fairly high overall angiosperm diversity was established in the middle(.) Campanian, the diversity remained relatively constant until at or near the end of the Maastrichtian.

  6. The Upper Campanian - lower Maastrichtian cephalopod fauna of Botellos, Nuevo León: a key to understand faunal turnover across the Campanian-Maastrichtian boundary in NE Mexico

    NASA Astrophysics Data System (ADS)

    Ifrim, Christina; De La Cerda, Jacobo Edgar Lara; Peña Ponce, Victor Hugo; Stinnesbeck, Wolfgang

    2017-03-01

    A new cephalopod collection from the Campanian-Maastrichtian boundary interval of NE Mexico, consisting of 1076 individuals assigned to 29 species and 22 genera is presented. This collection is a mix of ammonoids, one coleoid and one nautilid, which originate from at least three ammonoid biozones: The upper Campanian Exiteloceras jenneyi and Nostoceras (Nostoceras) hyatti zones, and the lower Maastrichtian Pachydiscus (Pachydiscus) neubergicus Zone. The age of the collection is thus middle late Campanian to late early Maastrichtian, and it closes a stratigraphic gap between faunas described formerly from this region. The specimens are nuclei collected from the desert pavement. The abundance of specimens allows for a comparison to other Campanian-Maastrichtian ammonoid records from Mexico, North America and Europe.

  7. An age-calibrated record of upper Campanian - Maastrichtian climate change in the Boreal Realm

    NASA Astrophysics Data System (ADS)

    Thibault, N.; Schovsbo, N.; Harlou, R.; Stemmerik, L.; Surlyk, F.

    2011-12-01

    The latest Cretaceous climate of the Boreal Realm was recorded through high-resolution bulk carbon- and oxygen-stable isotopes and a nannofossil temperature index (NTI) on the Stevns-1 core (Denmark) which recovered 456 m of upper Campanian to basal Danian chalk with ~100% recovery and an excellent continuity. Carbon isotope stratigraphy and nannofossil biostratigraphy were used to correlate Stevns-1 to two sites that bear an excellent magnetostratigraphic record: DSDP Site 525A and ODP Site 762C. The correlation of δ13C trends between the three sites and the use of the recent astronomical calibration of upper Campanian - Maastrichtian magnetochrons (Husson et al., 2011; K-Pg boundary at 66 Ma) led to the establishment of a precise age-model for Stevns-1. The good correlation between bulk δ18O and the NTI (R=-0.81) allows the use of oxygen stable isotopes to estimate past variations of sea surface temperatures (SSTs) in the Boreal Realm. Three warming events punctuate the overall cooling trend of the latest Cretaceous: (1) the late Campanian climatic optimum (73.9-71.6 Ma) is characterized by maximum SSTs of 20°C, (2) the mid-Maastrichtian warming (69.7-68 Ma) is characterized by stable SSTs around 17°C and (3) the end-Maastrichtian warming (66.37-66.03) is characterized by increasing SSTs up to 18°C. The two cooling events of the early (71.6-69.7 Ma) and late Maastrichtian (68-66.37 Ma) are both characterized by stable SSTs around 16°C. This Boreal record of SSTs derived from the δ18O of bulk nannofossil chalk is in agreement with planktic biotic events of the latest Cretaceous and matches well with climatic trends of intermediate- and deep-waters from other oceanic basins recorded through benthic foraminiferal δ18O (Barrera and Savin, 1999). However, most planktic foraminiferal δ18O data do not record well the mid- and end-Maastrichtian warmings. This suggests that the influence of changes in seawater pH and depth habitats of Campanian-Maastrichtian

  8. Maastrichtian-aged lithostratigraphic patterns in the European tethys: Implications for sea level change and end-Cretaceous extinction patterns

    SciTech Connect

    Ward, P.; Macleod, K.G. . Dept. of Geological Sciences)

    1992-01-01

    Thirteen Maastrichtian-aged stratigraphic sections from a variety of sites spanning the ancient Tethys ocean in Western and Eastern Europe and Northern Africa have been measured in this study. The similarity in lithologies between even geographically separated localities allows refined lithostratigraphic correlation; individual members first defined from Bay of Biscay sections can now be recognized through all sections. The sections are found in the Bay of Biscay and Basque region of France and Spain (Sopelana, Zumaya, Hendaye, Bidart, Tercis, Pamplona;) southern Spain (Caravaca, Agost); northern Africa (El Kef); and Eastern Europe (Georgia). All of the sections are dominated by limestones in the Lower Maastrichtian, and marls or limestone-marl rhythmites in the Upper Maastrichtian. A conspicuous, massive limestone, usually 10 to 15 m thick, is found in all sections at the top of the Lower Maastrichtian; it is invariably overlain by a thicker unit composed entirely of marl. The thick limestone contains the last body fossils of the genus Inoceramus, and occurs just beneath the first occurrence of foraminifera diagnostic of the Abathomphalus mayaroensis Zone of Late Maastrichtian age. The dramatic shift in lithology lies at or just beneath the boundary between the Lower and Upper Maastrichtian, and may have been caused by one of the most rapid and profound sea level changes of the Cretaceous Period. The sea-level change may be a causal factor in the mid-Maastrichtian extinction which affected the Inoceramidae and other mollusks, such as the rudistid bivalves and ammonites, and certainly is one of the dominant factors in forming the sequence of lithologies found in the Maastrichtian Stage of Tethys.

  9. The impact of the Maastrichtian cooling on the marine nutrient regime -- Evidence from midlatitudinal calcareous nannofossils

    NASA Astrophysics Data System (ADS)

    Linnert, Christian; Engelke, Julia; Wilmsen, Markus; Mutterlose, Jörg

    2016-06-01

    The latest Campanian-earliest Maastrichtian interval is well known as a period of intense climate cooling. This cooling caused a distinctive bipolar biogeographic distribution of calcareous nannofossil assemblages: High-latitude settings were dominated by newly evolving endemic taxa, former cosmopolitan species disappeared at the same time, and equatorial communities experienced an invasion of cool water taxa. The impact of this cooling on northern midlatitude assemblages is, however, less well known. In order to overcome this gap we studied the Kronsmoor section (northwest Germany). This section provides a continuous upper Campanian -- lower Maastrichtian succession with moderately to well preserved nannofossils. Uppermost Campanian assemblages are dominated by Prediscosphaera cretacea; other common taxa include Prediscosphaera stoveri, Watznaueria barnesiae, and Micula staurophora. The lower Maastrichtian is characterized by lower numbers of P. cretacea and frequent Kamptnerius magnificus, Arkhangelskiella cymbiformis, and Cribrosphaerella ehrenbergii. These changes reflect, in part, the Campanian-Maastrichtian boundary cooling since some successful taxa (e.g., K. magnificus) are related to cool surface waters. Other shifts in the nannofossil communities were perhaps the result of a changing nutrient regime. Stronger latitudinal gradients may have increased wind velocities and thus the eolian input of ferruginous dust required by N-fixing bacteria. The enhanced high-latitude deep water formation probably changed the bottom water environment in disfavor of denitrificating organisms. A decline of chemical weathering and fluviatile transport may have reduced the amount of bioavailable phosphate. These processes led to an increased nitrate and a decreased phosphate content shifting the nutrient regime from nitrate toward phosphate limitation.

  10. Two unusual new dinoflagellate cyst genera from the Bunde Borehole, Maastrichtian type area, southern Netherlands.

    PubMed

    Brinkhuis; Klinkenberg; Williams; Fensome

    2000-06-01

    Maastrichtian and Danian deposits from the Bunde Borehole in the Maastrichtian type area contain the morphologically unusual dinoflagellate species Spumadinium felderorum gen. et sp. nov. and Lasagniella herngreenii gen. et sp. nov., both of which have archeopyles formed by the loss of several paraplates. In S. felderorum the paraplates forming the operculum or opercular pieces appear to be the third and fourth precingulars (3"-4") plus the first and second anterior intercalaries (1a-2a). This suggests that Spumadinium, although having a wall resembling some cribroperidinioids, is a cladopyxiinean. L. herngreenii is unique in having up to eight wall layers, separated and supported by buttresses. The archeopyle is also a combination type but formed by loss of one apical (3'), three anterior intercalary (1a-3a) and three precingular (3"-5") paraplates. Thus, Lasagniella is assignable to the Peridiniales. The distinctive morphology and restricted ranges of the two genera make them useful stratigraphic markers for the Upper Maastrichtian-Danian.

  11. Inoceramid stratigraphy and depositional architecture of the Campanian and Maastrichtian of the Miechów Synclinorium (southern Poland)

    NASA Astrophysics Data System (ADS)

    Jurkowska, Agata

    2016-03-01

    Dynamic evolution of the Campanian and Maastrichtian (Upper Cretaceous) of the Miechow Synclinorium is presented. Through chronostratigraphic analysis, the geometry of the Campanian and Maastrichtian of the area is interpreted, while microfacies analysis allowed determination of some of the paleoenvironmental parameters (rate of sedimentation, bottom condition and terrigenous input). The chronostratigraphy is based on inoceramid biostratigraphy. Nine inoceramid zones are recognized: Sphenoceramus patootensiformis, Sphaeroceramus sarumensis-Cataceramus dariensis and `Inoceramus' azerbaydjanensis-`Inoceramus' vorhelmensis, `Inoceramus' tenuilineatus, Sphaeroceramus pertenuiformis, `Inoceramus' inkermanensis and `Inoceramus' costaecus- `Inoceramus' redbirdensis (Campanian); Endocostea typica and Trochoceramus radiosus (Maastrichtian). Five unconformities (isochronous in the study area) represented by horizons of slower sedimentation rate, were recognized. They correlate with eustatic sea-level changes, well recorded in European successions (Jarvis et al. 2002, 2006; Niebuhr et al. 2011). Unconformity horizons allow six alloformations to be distinguished. The thickness of particular chronostratigraphic units within the Campanian and Lower Maastrichtian increases progressively toward the axis of the Danish-Polish Trough, which indicates that the inversion of the trough could not have started before the Late Maastrichtian.

  12. Upper Maastrichtian ammonite biostratigraphy of the Gulf Coastal Plain (Mississippi Embayment, southern USA)

    USGS Publications Warehouse

    Larina, Ekaterina; Garb, Matthew P.; Landman, Neil H.; Dastas, Natalie; Thibault, Nicolas; Edwards, Lucy E.; Phillips, George; Rovelli, Remy; Myers, Corinne; Naujokaityte, Jone

    2016-01-01

    The Cretaceous outcrop belt of the Mississippi Embayment in the Gulf Coastal Plain (GCP) spans the Cretaceous/Paleogene (K/Pg) boundary. A detailed reconstruction of this time interval is critical for understanding the nature of biotic and environmental changes preceding the end-Cretaceous Mass Extinction event and for deciphering the likely extinction mechanism (i.e., bolide impact versus volcanism). Eight sections encompassing the K/Pg succession across the Mississippi Embayment were analyzed using biostratigraphic sampling of ammonites, dinoflagellates, and nannofossils. An upper Maastrichtian ammonite zonation is proposed as follows, from oldest to youngest:Discoscaphites conradi Zone, D. minardi Zone, and D. iris Zone. Our study documents that the ammonite zonation established in the Atlantic Coastal Plain (ACP) extends to the GCP. This zonation is integrated with nannofossil and dinoflagellate biostratigraphy to provide a framework to more accurately determine the age relationships in this region. We demonstrate that ammonites and dinoflagellates are more reliable stratigraphic indicators in this area than nannofossils because age-diagnostic nannofossils are not consistently present within the upper Maastrichtian in the GCP. This biostratigraphic framework has the potential to become a useful tool for correlation of strata both within the GCP and between the GCP, Western Interior, and ACP. The presence of the uppermost Maastrichtian ammonite D. iris, calcareous nannofossil Micula prinsii, and dinoflagellates Palynodinium grallator and Disphaerogena carposphaeropsis suggests that the K/Pg succession in the GCP is nearly complete. Consequently, the GCP is an excellent setting for investigating fine scale temporal changes across the K/Pg boundary and ultimately elucidating the mechanisms causing extinction.

  13. Volcanism and related Environmental changes linked to Late Maastrichtian High Stress and KT Mass Extinction

    NASA Astrophysics Data System (ADS)

    Keller, Gerta; Adatte, Thierry

    2010-05-01

    Near the end of the Maastrichtian Earth was hit by a confluence of catastrophes ranging from impacts to some of the most devastating volcanic eruptions coupled with major changes in climate, sea level and ocean chemistry that ultimately led to the Cretaceous-Tertiary boundary (KTB) mass extinction. For three decades this mass extinction has been commonly attributed to the sole kill-effect of the Chicxulub impact on Yucatan. Multi-disciplinary evidence (paleontologic, stratigraphic, sedimentologic geochemical) from the Yucatan impact crater to sections in Mexico and Texas revealed that this impact predates the KTB and caused no mass extinction. Recent studies reveal that the most devastating Deccan volcanic eruptions in India occurred near the end of the Maastrichtian and ended coincident with the KT mass extinction (Keller et al., 2008). Examination of biotic stress in the marine realm leading up to the KT mass extinction reveals times of environmental stresses associated with volcanism, greenhouse warming, mesotrophic basins and shallow marginal settings from the Tethys Ocean to the South Atlantic and Indian Oceans (Keller and Abramovich, 2009). Biotic stress conditions vary with the degree of environmental change and range from intraspecies size reduction, to loss of diversity and ultimately mass extinction. No significant biotic stress was observed in assemblages before and after the Chicxulub impact identified by a layer of impact spherules in late Maastrichtian sediments of zone CF1 predating the KTB in Mexico and Texas (Keller et al., 2009b,c). Maximum biotic stress leading to the KT mass extinction is associated with Deccan volcanism in India near the end of the Maastrichtian. This suggests that the mass extinction was likely a direct cause of Deccan volcanism, although the presence of a major Ir anomaly at the KTB does not rule out the possibility of a second major bolide impact exacerbating already catastrophic conditions. Keller, G., Adatte, T., Gardin, S

  14. Sphenodiscus pleurisepta (Conrad, 1857) from the Maastrichtian La Tabla Formation in the Upper Magdalena Valley, Tolima, Colombia

    NASA Astrophysics Data System (ADS)

    Patarroyo, Pedro; Bengtson, Peter; Guerrero, Javier

    2010-11-01

    The La Tabla Formation is an important petroleum reservoir in the Upper Magdalena Valley of Colombia. It was deposited in regressive and lowstand systems tracts and comprises a succession of lower shoreface to coastal plain deposits. A section in the Talora Creek, near the village of Piedras, Department of Tolima, exposes 90 m of a progradational to aggradational succession composed of very fine sandstones to medium-grained pebble conglomerates, with abundant planktic and benthic foraminifers as well as bivalves and ammonites. A few well-preserved phragmocones of the ammonite Sphenodiscus pleurisepta ( Conrad, 1857), collected from a level 63 m above the base of the formation, are here described and the chronostratigraphic position of the species discussed. In the Western Interior Basin of North America, S. pleurisepta ranges from the upper lower Maastrichtian Baculites clinolobatus Zone through the upper Maastrichtian Jeletzkytes nebrascensis Zone. The present findings support previous datings of the La Tabla Formation as Maastrichtian on the basis of foraminifers.

  15. Evidence for large-scale reworking of Campanian sediments into the Upper Maastrichtian Peedee formation at Burches Ferry, South Carolina

    USGS Publications Warehouse

    ,; Christopher, R.A.; Prowell, D.C.

    2002-01-01

    A 44-ft-deep corehole (FLO-311) was drilled at Burches Ferry, Florence County, S.C., in order to document the lithologic and paleontologic characteristics of the boundary between the upper Campanian Donoho Creek Formation and the upper Maastrichtian Peedee Formation. Palynomorph and calcareous nannofossil data provide detailed age control for these sediments. Examination of calcareous nannofossil assemblages shows that sediments from the type locality of the Peedee Formation consist largely of reworked Campanian materials. Robust Campanian species such as Reinhardtites anthophorus, Reinhardtites levis, and Stoverius asymmetricus commonly are found reworked into the Maastrichtian Peedee Formation in its entirety. Therefore, identification of lower upper Maastrichtian sediments is based on the presence of background assemblages rather than on the more traditional marker species. The presence of species restricted to the latest Campanian at the Donoho Creek-Peedee contact in outcrop indicates that the entire sedimentary package represented by calcareous nannofossil Zones CC23 and CC24 has been removed.

  16. New bio- and magnetostratigraphic data on Campanian‒Maastrichtian deposits of the classical Nizhnyaya Bannovka section (Volga river right bank, southern Saratov region)

    NASA Astrophysics Data System (ADS)

    Guzhikov, A. Yu.; Baraboshkin, E. Yu.; Beniamovsky, V. N.; Vishnevskaya, V. S.; Kopaevich, L. F.; Pervushov, E. M.; Guzhikova, A. A.

    2017-01-01

    The integral investigation of the upper Campanian‒Maastrichtian section near the settlement of Nizhnyaya Bannovka (Krasnoarmeiskii district, Saratov oblast) included its detailed lithological description and the study of different organic remains (belemnites, benthic and planktonic foraminifers, radiolarian, calcareous nannofossils, dinocysts) with the analysis of their taxonomic composition and stratigraphic distribution and magnetostratigraphic (magnetic polarity and petromagnetic) properties. The belemnite findings indicate the presence of the upper Campanian Belemnitella langei Zone in the section, which comprises sediments previously attributed to the lower Maastrichtian Belemnitella lanceolata Zone. The analogs of magnetic polarity chrons 33n, 32r, and 31n (probably superposed chrons 31n and 30) are established. It is assumed that radiolarians offer the opportunity to define the middle Campanian substage by analogy with the standard (international) stratigraphic scale. On the basis of benthic foraminifers, calcareous dinocysts, and paleomagnetic data, the late Maastrichtian age of sediments previously dated back to the early Maastrichtian is substantiated. A large hiatus corresponding to the terminal Campanian‒early Maastrichtian is revealed in the section. The succession of sedimentological, biotic, and paleogeographic events is outlined for the late Campanian‒Maastrichtian interval. The obtained data make it possible to disclose paleobiogeographic connections between microfaunal communities of the Campanian and late Maastrichtian seas on the East European and West Siberian plates. It is established that the uppermost Maastrichtian sediments are enriched in extraterrestrial matter.

  17. First evidence of Hadrosauropodus in Gondwana (Yacoraite Formation, Maastrichtian-Danian), northwestern Argentina

    NASA Astrophysics Data System (ADS)

    Díaz-Martínez, Ignacio; de Valais, Silvina; Cónsole-Gonella, Carlos

    2016-10-01

    Uppermost Cretaceous (Campanian-Maastrichtian) large ornithopod tracks are scarce in Gondwana. This record is limited to few citations in the northern Argentina, Peru and possibly Bolivia, although their ichnological affinities are still under discussion. Recently, a new vertebrate tracksite with large ornithopod tracks has been found in the Maimará locality, Jujuy province, Argentina, from the Yacoraite Formation (Maastrichtian-Danian). The best preserved track is characterized by having large and bilobed heel impression and wide and short digit impressions with blunt claw marks. This record represents the unambiguous record of large ornithopod tracks in Gondwana in the Uppermost Cretaceous, and its features allow classifying it as Hadrosauropodus. Previously, this ichnotaxon had exclusively Laurasian distribution. Therefore, this record is the first evidence of Hadrosauropodus from Gondwana expanding the geographic range of this ichnogenus. A member of Hadrosauridae is reinforced as possible trackmaker of the Hadrosauropodus tracks. Uppermost Cretaceous hadrosaurid dinosaurs are scarce in Gondwana, being the record limited to Patagonia, La Pampa province and Antarctica. Therefore, the Maimará tracks increase the knowledge of this kind of dinosaur from Gondwana.

  18. Soft sediment deformation structures in the Maastrichtian Ajali Formation Western Flank of Anambra Basin, Southern Nigeria

    NASA Astrophysics Data System (ADS)

    Olabode, Solomon Ojo

    2014-01-01

    Soft sediment deformation structures were recognized in the Maastrichtian shallow marine wave to tide influenced regressive sediments of Ajali Formation in the western flank of Anambra basin, southern Nigerian. The soft sediment deformation structures were in association with cross bedded sands, clay and silt and show different morphological types. Two main types recognised are plastic deformations represented by different types of recumbent folds and injection structure represented by clastic dykes. Other structures in association with the plastic deformation structures include distorted convolute lamination, subsidence lobes, pillars, cusps and sand balls. These structures are interpreted to have been formed by liquefaction and fluidization mechanisms. The driving forces inferred include gravitational instabilities and hydraulic processes. Facies analysis, detailed morphologic study of the soft sediment deformation structures and previous tectonic history of the basin indicate that the main trigger agent for deformation is earthquake shock. The soft sediment deformation structures recognised in the western part of Anambra basin provide a continuous record of the tectonic processes that acted on the regressive Ajali Formation during the Maastrichtian.

  19. Campano-Maastrichtian foraminifera from onshore sediments in the Rio del Rey Basin, Southwest Cameroon

    NASA Astrophysics Data System (ADS)

    Njoh, Oliver Anoh; Victor, Obiosio; Christopher, Agyingi

    2013-03-01

    Campanian-Maastrichtian marine sediments outcrop in five genetically linked sedimentary basins along the West African coast in the Gulf of Guinea, from the Douala Basin in Cameroon to the Anambra Basin in Nigeria. These sediments in the more centrally located Rio del Rey Basin have been the least studied. Therefore, the geologic history of this region has merely been speculative. The Rio del Rey Basin like the adjacent Niger Delta is producing hydrocarbon from the offshore Tertiary sedimentary interval in which all studies have been focused, neglecting the onshore Cretaceous sediments. Outcrops in the basin are rare, small and highly weathered. Samples from some of these sediments have yielded a few Planktonic and dominantly benthonic foraminiferal assemblages. The long-ranging heterohelix and hedbergellids characterized the planktics while the species Afrobolivina afra which is a well known diagnostic taxon for Campanian-Maastrichtian sediments in West African basins clearly dominate the benthic assemblage. Its occurrence in association with other Upper Cretaceous forms such as Bolivina explicata, Praebulimina exiqua, Gabonita lata, Ammobaculites coprolithiformis amongst others, formed the basis on which this age was assigned to the sediments sampled from the Rio del Rey Basin. Hence, this work has undoubtedly established the much needed link in this regional geologic history and correlates these sediments with the Logbaba and Nkporo Formations in the Douala Basin in Cameroon and the southeastern Nigerian Sedimentary Basins. Thus, these units were all deposited during this same geologic period and probably controlled by the same geologic event.

  20. Integrated biostratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland

    NASA Astrophysics Data System (ADS)

    Walaszczyk, Ireneusz; Dubicka, Zofia; Olszewska-Nejbert, Danuta; Remin, Zbigniew

    2016-09-01

    The biostratigraphic importance, current zonations, and potential for the recognition of the standard chronostratigraphic boundaries of five palaeontological groups (benthic foraminifers, ammonites, belemnites, inoceramid bivalves and echinoids), critical for the stratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland, are presented and discussed. The summary is based on recent studies in selected sections of southern Poland (Nida Synclinorium; Puławy Trough including the Middle Vistula River composite section; and Mielnik and Kornica sections of south-eastern Mazury-Podlasie Homocline) and of western Ukraine (Dubivtsi). The new zonation based on benthic forams is presented for the entire interval studied. Zonations for ammonites, belemnites and inoceramid bivalves are compiled. All stage boundaries, as currently defined or understood, may easily be constrained or precisely located with the groups discussed: the base of the Santonian with the First Occurrence (FO) of the inoceramid Cladoceramus undulatoplicatus; the base of the Campanian with the Last Occurrence (LO) of the crinoid Marsupites testudinarius and approximated by the range of the foraminifer Stensioeina pommerana; and the base of the Maastrichtian approximated by the FO of the inoceramid bivalve Endocostea typica and the FO of the belemnite Belemnella vistulensis. The positions of substage boundaries, as currently understood, are constrained in terms of the groups discussed.

  1. Calcareous nannofossil turnover dynamics across the late Campanian-Maastrichtian of the tropical South Atlantic

    NASA Astrophysics Data System (ADS)

    Thibault, Nicolas

    2017-04-01

    A detailed record of late Campanian-Maastrichtian calcareous nannofossil bio-events is presented for the South Atlantic reference DSDP Site 525A. The combination with magnetostratigraphy, chemostratigraphy and planktic foraminifer biostratigraphy allows for global correlations to other Tethyan and Boreal reference sections for that interval. A new time scale with a tie of Tethyan and Boreal nannofossil zonations is proposed. Cumulative first and last occurrences are used to delineate the turnover dynamics of calcareous nannoplankton which highlights 6 major events. Five of these events are related to major changes in sea-surface temperatures whereas the sixth event appears to be the expression of a global decrease in primary productivity in the late Maastrichtian. Surprisingly, the turnover dynamics in calcareous nannoplankton does not fit observations in planktic foraminiferal assemblages where only 4 major events were demonstrated with timings that differ from the 6 intervals of major change portrayed in the nannofossil assemblage. Regarding turnover, the two groups thus seem to have responded very differently to environmental pressure.

  2. Is Torosaurus Triceratops? Geometric Morphometric Evidence of Late Maastrichtian Ceratopsid Dinosaurs

    PubMed Central

    Maiorino, Leonardo; Farke, Andrew A.; Kotsakis, Tassos; Piras, Paolo

    2013-01-01

    Background Recent assessments of morphological changes in the frill during ontogeny hypothesized that the late Maastrichtian horned dinosaur Torosaurus represents the “old adult” of Triceratops, although acceptance of this finding has been disputed on several lines of evidence. Methodology/Principal Findings Examining the cranial morphology of 28 skulls in lateral view and 36 squamosals of Nedoceratops hatcheri, Triceratops spp. and Torosaurus spp. by means of landmark-based geometric morphometrics, we compared ontogenetic trajectories among these taxa. Principal Component Analysis and cluster analysis confirmed different cranial morphologies. Torosaurus shape space is well separated from Triceratops, whereas Triceratops horridus and Triceratops prorsus partially overlap within Triceratops shape space. Linear regressions between shape and size suggest different ontogenetic trajectories among these taxa. Results support the “traditional” taxonomic status of Torosaurus. We hypothesize that ontogeny drives cranial morphology with different patterns between Torosaurus and Triceratops. Conclusions/Significance Torosaurus is a distinct and valid taxon. Whether looking at entire skulls, skulls without the frill, frills alone, or squamosals, Torosaurus has different morphologies and distinct allometric trajectories compared to Triceratops. This new approach confirms the taxonomic status of Torosaurus as well as the comparatively low diversity of ceratopsids at the end of the Maastrichtian in North America. PMID:24303058

  3. Hydrologically Correct, Global Paleo-Digital Elevation Models (DEMs): a Maastrichtian (Late Cretaceous) Example

    NASA Astrophysics Data System (ADS)

    Markwick, P. J.

    2001-12-01

    The past surface relief of the Earth is an essential boundary condition for computer-based atmosphere and ocean modeling. It also provides the geographic context for understanding surface processes and biotic distributions and interactions. However, with increased model resolution and the addition of vegetation, soil (weathering) and chemical modules, there is now a need for more robust, detailed paleo-topographies and bathymetries that are fully integrated with the processes being modeled, especially the hydrological system (hydrologically correct). Here I present a new GIS-based, hydrologically correct, paleo-DEM for the Maastrichtian (Late Cretaceous). This project was initiated in 1995 while the author was a graduate at the University of Chicago using the plate reconstructions of Rowley (1995, unpublished). The Maastrichtian paleogeography used in this study is one of a series of 27 global maps, representing the Cretaceous and Cenozoic, being compiled simultaneously to ensure continuity between each time interval. Each map is generated at a scale of 1:30 million in ArcView GIS and ArcInfo, using data from the author's own databases of lithologic, tectonic and fossil information, the lithologic databases of the Paleogeographic Atlas Project (The University of Chicago), a survey of published literature, and DSDP / ODP data. Interpretations of elevation are derived following the methods outlined in Ziegler et al (1985), an understanding of the tectonic regime and evolution of each geographic feature, and the age-depth relationship for the ocean. The Maastrichtian has been completed first to provide the boundary conditions for a coupled atmosphere-ocean experiment. The hydrologically correct global DEM was derived using the elevation contours from the paleogeography and the suite of hydrological tools now available in ArcInfo GRID. The DEM has been constrained by defining areas of paleo-internal drainage, paleo-river mouths and known paleo-river courses. When

  4. Coupled Climate Model Simulations of a Late Cretaceous (Maastrichtian) Greenhouse Climate: Comparison with Proxy Data

    NASA Astrophysics Data System (ADS)

    Upchurch, G. R.; Kiehl, J. T.; Shields, C. A.; Scotese, C.

    2009-12-01

    Earth’s future climate is expected to warm considerably due to increased atmospheric carbon dioxide. Paleoclimate records indicate that pre-Quaternary time periods provide the best possible view of Earth under warm greenhouse conditions. Thus, past warm greenhouse climates provide an important tool to evaluate fully coupled climate models that are currently used to study future climate change. In this study, we use the Community Climate System Model (CCSM3) to investigate the climate of the latest Cretaceous (Maastrichtian). CCSM3 is a fully coupled three-dimensional global model that includes atmospheric, oceanic, sea-ice and terrestrial processes. The CCSM3 simulations employ slight modifications of the paleogeographic and global vegetation reconstructions used in earlier simulations of the late Maastrichtian with the GENESIS Earth System Model (Upchurch, Otto-Bliesner, and Scotese, 1999). CCSM3 simulations include two levels of atmospheric carbon dioxide (2XPAL and 6XPAL), best estimates of atmospheric methane, changes to low level liquid cloud properties based on the hypothesis of Kump and Pollard (2008), and different paleoelevations for the interior of Siberia. A coupled simulation of multi-century length is carried out to study steady state conditions for the surface ocean. For terrestrial regions, model mean annual temperatures and seasonality are compared with data from angiosperm leaf physiognomy, plant life form distribution, and other climatic indicators to determine how well the model represents high latitude warmth on a zonal and regional basis. Model precipitation is compared with a database of climatically restricted sediments and angiosperm leaf physiognomy for specific sites. For oceanic regions, the CCSM3 simulations are compared to marine proxies of surface and benthic temperatures, especially the δ18O of exceptionally preserved carbonate. Our simulations reproduce many features of Maastrichtian climate, such as the latitudinal gradient of

  5. Mosasaurs (Reptilia) from the late Maastrichtian (Late Cretaceous) of northern Patagonia (Río Negro, Argentina)

    NASA Astrophysics Data System (ADS)

    Fernández, Marta; Martin, James; Casadío, Silvio

    2008-03-01

    A diverse assemblage of mosasaurs was recently recovered from the Jagüel Formation (late Maastrichtian) exposed at three localities of northern Patagonia (Río Negro, Argentina). Four taxa (three mosasaurines and a plioplatecarpine) have been identified, and three of these marine reptiles can be identified at lower taxonomic levels: Mosasaurus sp. aff. M. hoffmanni, Plioplatecarpus sp., and Prognathodon sp. These occurrences are significant because they represent the first diagnostic material at generic level exhumed from Patagonia and include one of the youngest mosasaurs found worldwide. One of the specimens described herein was found only 1.5 m below the Cretaceous/Tertiary boundary. Only mosasaurs from Antarctica found within a meter of the boundary are known to occur higher in the geologic section.

  6. Depositional facies and eustatic effects in Upper Cretaceous (Maastrichtian) Ripley Formation, central and eastern Alabama

    SciTech Connect

    Skotnicki, M.C.; King, D.T. Jr. )

    1989-09-01

    In eastern and central Alabama, the Upper Cretaceous Ripley Formation (40-175 m thick) is comprised of five depositional facies. Facies 1 (barrier-island shoreface and tidal-inlet fill) is a medium to coarse, intraclastic quartzose sand that is planar and trough cross-stratified and has abundant Ophiomorpha traces. Facies 2 (back-barrier lagoon or marsh) is a bioturbated, micaceous, carbonaceous silt that contains macerated plant debris and bivalve molds and impressions. Interbedded with facies 2 is facies 3 (storm-washover deposits), a hummocky cross-stratified, micaceous fine sand. Facies 4 (back-barrier tidal flat) is a micaceous silty clay lacking body fossils and plant debris. Facies 5 (lower shoreface) is a glauconitic, clayey and micaceous, fine to medium sand that is highly bioturbated and commonly has abundant marine macrofauna. The Ripley is divided into two genetic packages of facies; the genetic packages are bounded by stratigraphic breaks or discontinuities. The package-bounding breaks are correlated biostratigraphically with discrete third-order eustatic drops on the world sea level curve. The basal Ripley break is correlated with the end of Campanian (about 74 Ma) eustatic drop, and the middle Ripley break (separating the two genetic packages) marks the mid-Maastrichtian (71 Ma) sea level drop. The basal and middle Ripley breaks are low-relief surfaces marked by sharp facies discontinuities (correlatable across 130 km) and terminal coarsening-upward cycles (5 m thick); the estimated eustatic sea level fall in both instances was about 50 m. The break at the top of the Ripley has 70 m of erosional relief and a bone bed up to 80 cm thick. This break represents a late Maastrichtian (about 68 Ma) sea level fall estimated to have been nearly 95 m. Facies of the superjacent Prairie Bluff Chalk and Providence Sand overlie the erosional surface.

  7. Natural gas accumulations in low-permeability Tertiary, and Cretaceous (Campanian and Maastrichtian) rock, Uinta Basin, Utah

    SciTech Connect

    Fouch, T.D.; Wandrey, C.J.; Pitman, J.K.; Nuccio, V.F.; Schmoker, J.W.; Rice, D.D.; Johnson, R.C.; Dolton, G.L.

    1992-02-01

    This report characterizes Upper Cretaceous Campanian and Maastrichtian, and lower Tertiary gas-bearing rocks in the Uinta Basin with special emphasis on those units that contain gas in reservoirs that have been described as being tight. The report was prepared for the USDOE whose Western Tight Gas Sandstone Program cofunded much of this research in conjunction with the US Geological Survey's Evolution of Sedimentary Basins, and Onshore Oil and Gas Programs. (VC)

  8. Natural gas accumulations in low-permeability Tertiary, and Cretaceous (Campanian and Maastrichtian) rock, Uinta Basin, Utah. Final report

    SciTech Connect

    Fouch, T.D.; Wandrey, C.J.; Pitman, J.K.; Nuccio, V.F.; Schmoker, J.W.; Rice, D.D.; Johnson, R.C.; Dolton, G.L.

    1992-02-01

    This report characterizes Upper Cretaceous Campanian and Maastrichtian, and lower Tertiary gas-bearing rocks in the Uinta Basin with special emphasis on those units that contain gas in reservoirs that have been described as being tight. The report was prepared for the USDOE whose Western Tight Gas Sandstone Program cofunded much of this research in conjunction with the US Geological Survey`s Evolution of Sedimentary Basins, and Onshore Oil and Gas Programs. (VC)

  9. Geodynamic Evolution of Northeastern Tunisia During the Maastrichtian-Paleocene Time: Insights from Integrated Seismic Stratigraphic Analysis

    NASA Astrophysics Data System (ADS)

    Abidi, Oussama; Inoubli, Mohamed Hédi; Sebei, Kawthar; Amiri, Adnen; Boussiga, Haifa; Nasr, Imen Hamdi; Salem, Abdelhamid Ben; Elabed, Mahmoud

    2017-05-01

    The Maastrichtian-Paleocene El Haria formation was studied and defined in Tunisia on the basis of outcrops and borehole data; few studies were interested in its three-dimensional extent. In this paper, the El Haria formation is reviewed in the context of a tectono-stratigraphic interval using an integrated seismic stratigraphic analysis based on borehole lithology logs, electrical well logging, well shots, vertical seismic profiles and post-stack surface data. Seismic analysis benefits from appropriate calibration with borehole data, conventional interpretation, velocity mapping, seismic attributes and post-stack model-based inversion. The applied methodology proved to be powerful for charactering the marly Maastrichtian-Paleocene interval of the El Haria formation. Migrated seismic sections together with borehole measurements are used to detail the three-dimensional changes in thickness, facies and depositional environment in the Cap Bon and Gulf of Hammamet regions during the Maastrichtian-Paleocene time. Furthermore, dating based on their microfossil content divulges local and multiple internal hiatuses within the El Haria formation which are related to the geodynamic evolution of the depositional floor since the Campanian stage. Interpreted seismic sections display concordance, unconformities, pinchouts, sedimentary gaps, incised valleys and syn-sedimentary normal faulting. Based on the seismic reflection geometry and terminations, seven sequences are delineated. These sequences are related to base-level changes as the combination of depositional floor paleo-topography, tectonic forces, subsidence and the developed accommodation space. These factors controlled the occurrence of the various parts of the Maastrichtian-Paleocene interval. Detailed examinations of these deposits together with the analysis of the structural deformation at different time periods allowed us to obtain a better understanding of the sediment architecture in depth and the delineation of

  10. Geodynamic Evolution of Northeastern Tunisia During the Maastrichtian-Paleocene Time: Insights from Integrated Seismic Stratigraphic Analysis

    NASA Astrophysics Data System (ADS)

    Abidi, Oussama; Inoubli, Mohamed Hédi; Sebei, Kawthar; Amiri, Adnen; Boussiga, Haifa; Nasr, Imen Hamdi; Salem, Abdelhamid Ben; Elabed, Mahmoud

    2016-12-01

    The Maastrichtian-Paleocene El Haria formation was studied and defined in Tunisia on the basis of outcrops and borehole data; few studies were interested in its three-dimensional extent. In this paper, the El Haria formation is reviewed in the context of a tectono-stratigraphic interval using an integrated seismic stratigraphic analysis based on borehole lithology logs, electrical well logging, well shots, vertical seismic profiles and post-stack surface data. Seismic analysis benefits from appropriate calibration with borehole data, conventional interpretation, velocity mapping, seismic attributes and post-stack model-based inversion. The applied methodology proved to be powerful for charactering the marly Maastrichtian-Paleocene interval of the El Haria formation. Migrated seismic sections together with borehole measurements are used to detail the three-dimensional changes in thickness, facies and depositional environment in the Cap Bon and Gulf of Hammamet regions during the Maastrichtian-Paleocene time. Furthermore, dating based on their microfossil content divulges local and multiple internal hiatuses within the El Haria formation which are related to the geodynamic evolution of the depositional floor since the Campanian stage. Interpreted seismic sections display concordance, unconformities, pinchouts, sedimentary gaps, incised valleys and syn-sedimentary normal faulting. Based on the seismic reflection geometry and terminations, seven sequences are delineated. These sequences are related to base-level changes as the combination of depositional floor paleo-topography, tectonic forces, subsidence and the developed accommodation space. These factors controlled the occurrence of the various parts of the Maastrichtian-Paleocene interval. Detailed examinations of these deposits together with the analysis of the structural deformation at different time periods allowed us to obtain a better understanding of the sediment architecture in depth and the delineation of

  11. A multidisciplinary approach to reservoir subdivision of the Maastrichtian chalk in the Dan field, Danish North Sea

    SciTech Connect

    Kristensen, L.; Dons, T.; Schioler, P.

    1995-11-01

    Correlation of wireline log data from the North Sea chalk reservoirs is frequently hampered by rather subtle log patterns in the chalk section due to the apparent monotonous nature of the chalk sediments, which may lead to ambiguous correlations. This study deals with a correlation technique based on an integration of biostratigraphic data, seismic interpretation, and wireline log correlation; this technique aims at producing a consistent reservoir subdivision that honors both the well data and the seismic data. This multidisciplinary approach has been used to subdivide and correlate the Maastrichtian chalk in the Dan field. The biostratigraphic subdivision is based on a new detailed dinoflagellate study of core samples from eight wells. Integrating the biostratigraphic results with three-dimensional seismic data allows recognition of four stratigraphic units within the Maastrichtian, bounded by assumed chronostratigraphic horizons. This subdivision is further refined by adding a seismic horizon and four horizons from wireline log correlations, establishing a total of nine reservoir units. The approximate chronostratigraphic nature of these units provides an improved interpretation of the depositional and structural patterns in this area. The three upper reservoir units pinch out and disappear in a northeasterly direction across the field. We interpret this stratal pattern as reflecting a relative sea level fall or regional basinal subsidence during the latest Maastrichtian, possibly combined with local synsedimentary uplift due to salt tectonics. Isochore maps indicate that the underlying six non-wedging units are unaffected by salt tectonics.

  12. Maastrichtian-Early Eocene litho-biostratigraphy and palægeography of the northern Gulf of Suez region, Egypt

    NASA Astrophysics Data System (ADS)

    Scheibner, C.; Marzouk, A. M.; Kuss, J.

    2001-02-01

    The Maastrichtian-Lower Eocene sediments on both sides of the northern Gulf of Suez can be subdivided into eight formal formations (including one group) and one informal formation that are described in detail. These lithostratigraphic units reflect three different environmental regimes of deposition or non-deposition. The first regime is characterised by uplift and erosion or non-deposition resulting mostly from the uplift of the Northern Galala/Wadi Araba structure, a branch of the Syrian Arc Foldbelt. The shallow water carbonate platform and slope deposits of the Late Campanian-Maastrichtian St Anthony Formation and the Paleocene-Lower Eocene Southern Galala and Garra Formations represent the second regime and are found north and south of the Northern Galala/Wadi Araba High. The third regime is represented by basinal chalks, marls and shales of the Maastrichtian Sudr Formation and of the Paleocene-Eocene Dakhla, Tarawan and Esna Formations, the Dakhla/Tarawan/Esna informal formation and the Thebes Group. The distribution and lateral interfingering of the above mentioned environmental regimes reflect different vertical movements, changing basin morphology, sea level changes and progradation of shallow water sediments and is illustrated on 11 palæogeographic maps.

  13. A dromaeosaur from the Maastrichtian of James Ross Island and the Late Cretaceous Antarctic dinosaur fauna

    USGS Publications Warehouse

    Case, Judd A.; Martin, James E.; Reguero, Marcelo

    2007-01-01

    The recovery of material of a small theropod from the Early Maastrichtian, Cape Lamb Member of the Snow Hill Island Formation is an unusual occurrence from primarily marine sediments. The pedal morphology of the specimen that includes a Metatarsal II with a lateral expansion caudal to Metatarsal III, a third metatarsal that is proximally narrow and distally wide, a Metatarsal III with a distal end that is incipiently ginglymoidal and a second pedal digit with sickle-like ungual are all diagnostic of a theropod that belongs to the family of predatory dinosaurs, the Dromaeosauridae. Yet this Antarctic dromaeosaur retains plesiomorphic features in its ankle and foot morphology. As new dromaeosaur species are being recovered from the mid-Cretaceous of South America and the retention of primitive characters in the Antarctic dromaeosaur, a new biogeographic hypothesis on dromaeosaur distribution has been generated. Gondwanan dromaeosaurs are not North America immigrants into South America and Antarctica; rather they are the relicts of a cosmopolitan dromaeosaur distribution, which has been separated by the vicariant break up of Pangea and created an endemic clade of dromaeosaurs in Gondwana.

  14. Occurrence of a young elasmosaurid plesiosaur skeleton from the Late Cretaceous (Maastrichtian) of Antarctica

    USGS Publications Warehouse

    Martin, James E.; Sawyer, J. Foster; Reguero, Marcelo; Case, Judd A.

    2007-01-01

    The most completely articulated fossil skeleton heretofore found on the continent of Antarctica is represented by a juvenile plesiosaur. The specimen was found in the Sandwich Bluff area of Vega Island east of the Antarctic Peninsula from Late Cretaceous (Maastrichtian) marine deposits from the upper Snow Hill Island Formation. The plesiosaur skeleton is represented by a nearly complete torso, partial paddles, and neck and tail sections. Along the ventral margin of the torso are articulated gastralia, some that are unusual in being forked. Numerous small gastroliths are associated within the trunk cavity, indicating that even juveniles ingest gastroliths. Coupled with other known specimens, the skeleton indicates shallow marine environment may have been an area where marine reptiles had their young, and the young remained until reaching maturity prior to facing open marine environments. The morphology of the specimen suggests the skeleton represents a juvenile Mauisaurus, an elasmosaurid plesiosaur taxon originally described from New Zealand and endemic to the Weddellian Province of the austral region.

  15. Carbon and oxygen isotopes of Maastrichtian Danian shallow marine carbonates: Yacoraite Formation, northwestern Argentina

    NASA Astrophysics Data System (ADS)

    Marquillas, Rosa; Sabino, Ignacio; Nobrega Sial, Alcides; Papa, Cecilia del; Ferreira, Valderez; Matthews, Stephen

    2007-04-01

    The Maastrichtian-Danian limestones of the Yacoraite Formation (northwestern Argentina) show carbon and oxygen isotopic values consistent with shallow marine conditions. The members of the formation respond to different sedimentary environments and are characterised by distinctive stable isotopes and geochemistry. The basal Amblayo Member is composed of high-energy dolomitic limestones and limestones with positive isotopic values (+2‰ δ 13C, +2‰ δ 18O). The top of the member reveals an isotopic shift of δ 13C (-5‰) and δ 18O (-10‰), probably related to a descent in the sea level. The sandy Güemes Member has isotopically negative (-2‰ δ 13C, -1‰ δ 18O) limestones, principally controlled by water mixing, decreased organic productivity, and compositional changes in the carbonates. The isotopically lighter limestones are calcitic, with a greater terrigenous contribution and different geochemical composition (high Si-Mn-Fe-Na, low Ca-Mg-Sr). These isotopic and lithological changes relate to the Cretaceous-Palaeogene transition. The Alemanía Member, composed of dolomitic limestones and pelites, represents a return to marine conditions and shows a gradual increase in isotopic values, reaching values similar to those of the Amblayo Member. The Juramento Member, composed of stromatolite limestones, shows isotopic variations that can be correlated with the two well-defined, shallowing-upward sequences of the member.

  16. Stable isotope distribution in continental Maastrichtian vertebrates from the Haţeg Basin, South Carpathians

    NASA Astrophysics Data System (ADS)

    Bojar, Ana-Voica; Csiki, Zoltan; Grigorescu, Dan

    2010-05-01

    The oxygen isotopic compositions of biogenic apatite from crocodiles, turtles and dinosaurs, and their relationship to climate and physiology have been evidenced by several studies (Barrick and Showers, 1995; Kolodny et al., 1996; Barrick et al., 1999; Fricke and Rogers, 2000; Stoskopf et al., 2001; Straight et al., 2004; Amiot et al., 2007). To date, few attempts have been made to correlate the enamel d13C to dietary resources of dinosaurs (Bocherens et al., 1988; Stanton Thomas and Carlson, 2004; Fricke and Pearson, 2008; Fricke, et al., 2008). One additional complication is that for dinosaurs, the d18O of enamel phosphate depends on both body water and variations in body temperature. Several studies addressed the issue of endothermy vs. ectothermy of fossil vertebrates by studying inter- and intra-bone and enamel isotopic variability (Barrick and Showers, 1994, 1995; Barrick et al., 1996; 1998; Fricke and Rogers, 2000). More recent investigations provided evidence for inter-tooth temporal variations and related them to seasonality and/or changes in physiology (Straight et al., 2004; Stanton Thomas and Carlson, 2004). The main objectives of this study are to extract palaeoclimatic information considering, beside lithofacial characteristics and the isotopic distribution of carbonates formed in paleosols, the stable isotope composition of vertebrate remains from the Haţeg Basin. We also sampled several teeth along their growth axis in order to get further information about growth rates and the amplitude of isotopic variation. Located in the South Carpathians in Romania, the Haţeg Basin contains a thick sequence of Maastrichtian continental deposits yielding a rich dinosaur and mammalian fauna. Stable isotope analyses of both calcretes and dinosaur, crocodilian and turtle remains from two localities (Tuştea and Sibişel) were integrated in order to reconstruct environmental conditions during the Maastrichtian time and to gain further insights into the metabolism

  17. Paleoenvironmental signals and paleoclimatic condition of the Early Maastrichtian oil shales from Central Eastern Desert, Egypt

    NASA Astrophysics Data System (ADS)

    Fathy, Douaa; Wagreich, Michael; Zaki, Rafat; Mohamed, Ramadan S. A.

    2016-04-01

    Early Maastrichtian oil shales are hosted in the Duwi Formation of the Central Eastern Desert, Egypt. The examined member represents up to 20% of the total Duwi Formation. This interval is mainly composed of siliciclastic facies, phosphorites facies and carbonate facies. Oil shales microfacies is mainly composed of smectite, kaolinite, calcite, fluorapatite, quartz and pyrite. They are enriched in a number of major elements and trace metals in particular Ca, P, V, Ni, Cr, Sr, Zn, Mo, Nb, U and Y compared to the post-Archaean Australian shale (PAAS). Chondrite-normalized REEs patterns of oil shales for the studied area display light rare earth elements enrichment relatively to heavy rare earth elements with negative Ce/Ce* and Eu/Eu* anomalies. The most remarkable indicators for redox conditions are enrichments of V, Mo, Ni, Cr, U content and depletion of Mn content. Besides, V/V+Ni, V/Ni, U/Th, Ni/Co, authigentic uranium ratios with presence of framboidal shape of pyrite and its size are reflecting the deposition of these shales under marine anoxic to euxinic environmental conditions. Additionally, the ratio of Strontium (Sr) to Barium (Ba) Sr/Ba reflected highly saline water during deposition. Elemental ratios critical to paleoclimate and paleoweathering (Rb /Sr, Al2O3/TiO2), CIA values, binary diagram between (Al2O3+K2O+Na2O) and SiO2 and types of clay minerals dominated reflect warm to humid climate conditions prevailing during the accumulation of these organic-rich petroleum source rocks.

  18. Biogeochemial Cycling and Ocean Climate in the Maastrichtian: a Coupled Ecosystem-Physical Climate Simulation Study

    NASA Astrophysics Data System (ADS)

    Williams, J.; Valdes, P. J.

    2014-12-01

    Paleoclimate simulations of the Latest Cretaceous are presented, specifically for the Maastrichtian stage using the UK Met Office model HadCM3L. The vast majority of traditional paleoclimate simulation studies using General Circulation Models include representations of the atmosphere and ocean as well as a dynamic sea ice model. In this we study new presents model results from a GCM that also includes a detailed ocean biogeochemical scheme HadOCC. HadOCC is an ecosystem model, meaning it contains an explicit representation of planktonic species (both autotrophic phytoplankton and heterotrophic zooplankton) and is an NZPD model (Nutrient, Phytoplankton, Zooplankton, Detritus). It is also able to simulate air-sea gas exchange and primary productivity in the surface and near-surface as well as full ecosystem interaction throughout the water column. Compared to the present day, the Latest Cretaceous represents a very different world, both in terms of its atmospheric composition and in the configuration of the continents. It also offers the prospect of studying a past warm climate with significantly enhanced CO2 levels compared to the preindustrial era. For the simulations presented here, atmospheric CO2 levels are set to be four times their preindustrial values (290 parts per million). The combination of a very different continental configuration and hugely enhanced atmospheric CO2 levels results in a very different climate from what we know today. To first order, ocean temperatures are significantly higher and circulation patterns are very different. The combination of these fundamentally important ocean properties means that the resulting biological activity (which will be shown in an annual mean and seasonal sense) is able to provide clues as to which oceanic areas were more biologically active than others. Because of the fully dynamic and coupled nature of the biology and physics of this modelling framework, surface and benthic processes (and their interactions

  19. Late Maastrichtian chalk mounds, Stevns Klint, Denmark — Combined physical and biogenic structures

    NASA Astrophysics Data System (ADS)

    Anderskouv, Kresten; Damholt, Tove; Surlyk, Finn

    2007-08-01

    Upper Maastrichtian chalk exposed at the Sigerslev quarry, Stevns Klint, Denmark is characterized by wavy and mound-like bedding geometries outlined by bands of black flint nodules. Four morphological elements are recognized, although bedding geometries are highly variable: southward migrating mounds, eastward migrating mounds, chalk waves and evenly bedded chalk. The mounds are interpreted as having been formed by currents carrying fine-grained suspended sediment which was primarily deposited on the up-current mound flanks. Bryozoans were prolific on the up-current flanks and mound summits, which stabilized the mounds, increased bed roughness and the overall accumulation rate. However, accumulation thicknesses do not correlate consistently with bryozoan density. The bryozoans were therefore important for the formation of the mounds, but the distribution of bryozoans did not solely determine depositional thickness across a mound and thus mound growth pattern. Relatively long wavelength wavy-bedded chalk show gentle convex-up geometries and would probably be described as sediment waves if recognized in seismic sections. The chalk waves were deposited under weaker current velocities than those active during mound formation. The exposed succession is topped by more evenly bedded chalk which was deposited by quiet pelagic fall-out of fine-grained material. The whole succession was deposited on the upper part of the northern flank of a large WNW-ESE trending 3 km wide depositional ridge with an amplitude of 35-40 m formed by contour-parallel WNW-ward flowing bottom currents. The mounds may have been deposited by regional bottom currents, or by spill-over currents from the valley south of the large ridge. The succession was deposited during varying bottom current intensities and the depositional architecture indicates a complex and dynamic environment. The depositional style seems to be controlled by the interplay and relative importance of two end-member processes

  20. The benthic macrofauna from the Lower Maastrichtian chalk of Kronsmoor (northern Germany, Saturn quarry): taxonomic outline and palaeoecologic implications

    NASA Astrophysics Data System (ADS)

    Engelke, Julia; Esser, Klaus J. K.; Linnert, Christian; Mutterlose, Jörg; Wilmsen, Markus

    2016-12-01

    The benthic macroinvertebrates of the Lower Maastrichtian chalk of Saturn quarry at Kronsmoor (northern Germany) have been studied taxonomically based on more than 1,000 specimens. Two successive benthic macrofossil assemblages were recognised: the lower interval in the upper part of the Kronsmoor Formation (Belemnella obtusa Zone) is characterized by low abundances of macroinvertebrates while the upper interval in the uppermost Kronsmoor and lowermost Hemmoor formations (lower to middle Belemnella sumensis Zone) shows a high macroinvertebrate abundance (eight times more than in the B. obtusa Zone) and a conspicuous dominance of brachiopods. The palaeoecological analysis of these two assemblages indicates the presence of eight different guilds, of which epifaunal suspension feeders (fixo-sessile and libero-sessile guilds), comprising approximately half of the trophic nucleus of the lower interval, increased to a dominant 86% in the upper interval, including a considerable proportion of rhynchonelliform brachiopods. It is tempting to relate this shift from the lower to the upper interval to an increase in nutrient supply and/or a shallowing of the depositional environment but further data including geochemical proxies are needed to fully understand the macrofossil distribution patterns in the Lower Maastrichtian of Kronsmoor.

  1. Upper Cretaceous (Maastrichtian) Charophyte Gyrogonites from the Lameta Formation of Jabalpur, Central India: Palaeobiogeographic and Palaeoecological Implications

    NASA Astrophysics Data System (ADS)

    Khosla, Ashu

    2014-12-01

    A charophyte gyrogonite assemblage consisting of Platychara cf. sahnii, Nemegtichara grambastii and Microchara sp. is reported herein from two localities (Bara Simla Hill and Chui Hill sections) of the Lameta Formation at Jabalpur. he Lameta Formation locally underlying the Deccan traps has been shown to be pedogenically modified alluvial plain deposits containing one of the most extensive dinosaur nesting sites in the world. They are associated with dinosaur bones and freshwater ostracod assemblages that suggest a Late Cretaceous (Maastrichtian) age. This is the first detailed systematic account of charophyte gyrogonites from the Lameta Formation. This charophyte assemblage is compatible with the biostratigraphic attribution provided by the ostracods. From a biogeographic viewpoint, it exhibits considerable similarity to other infratrappean assemblages of the Nand, Dongargaon, and Dhamni-Pavna sections (Maharashtra), and some intertrappean assemblages of Kora in Gujarat, Rangapur in Andhra Pradesh and Gurmatkal in South India. Globally, the genus Microchara is well distributed throughout Eurasia, whereas the genus Platychara occurs richly in the Upper Cretaceous deposits of Europe, Asia, America and Africa. However, at the specific level, Platychara cf. sahnii shows close affinities with charophytes from the Maastrichtian of Iran whilst Nemegtichara grambastii shows distinct affinities with two species of Early Palaeogene deposits of China and Mongolia. The presence of charophyte gyrogonites in the Lameta sediments is attributed to local lacustrine and palustrine conditions within a flood plain environment.

  2. Coryphoid palm leaf fossils from the Maastrichtian-Danian of Central India with remarks on phytogeography of the Coryphoideae (Arecaceae).

    PubMed

    Srivastava, Rashmi; Srivastava, Gaurav; Dilcher, David L

    2014-01-01

    A large number of fossil coryphoid palm wood and fruits have been reported from the Deccan Intertrappean beds of India. We document the oldest well-preserved and very rare costapalmate palm leaves and inflorescence like structures from the same horizon. A number of specimens were collected from Maastrichtian-Danian sediments of the Deccan Intertrappean beds, Ghughua, near Umaria, Dindori District, Madhya Pradesh, India. The specimens are compared with modern and fossil taxa of the family Arecaceae. Sabalites dindoriensis sp. nov. is described based on fossil leaf specimens including basal to apical parts. These are the oldest coryphoid fossil palm leaves from India as well as, at the time of deposition, from the Gondwana- derived continents. The fossil record of coryphoid palm leaves presented here and reported from the Eurasian localities suggests that this is the oldest record of coryphoid palm leaves from India and also from the Gondwana- derived continents suggesting that the coryphoid palms were well established and wide spread on both northern and southern hemispheres by the Maastrichtian-Danian. The coryphoid palms probably dispersed into India from Europe via Africa during the latest Cretaceous long before the Indian Plate collided with the Eurasian Plate.

  3. An unrecognized development of retro-arc foreland basin system in northeast China during late Cretaceous (Campanian-Maastrichtian)

    NASA Astrophysics Data System (ADS)

    Zhang, F. Q., Sr.; Chen, H.; Dilek, Y.; Yang, S.; Meng, Q. A.

    2016-12-01

    Regional variations of stratigraphy, internal structures and infill architecture defined an unrecognized Campanian-Maastrichtian retro-arc foreland basin system in northeast China. In the most proximal part of this foreland basin system, the discrete Upper Cretaceous of the eastern zone suffered multi-stage intense folding-thrusting deformation before early Cenozoic extension. The continuous Cretaceous Songliao Basin of the central zone, almost occupied the main position of the foredeep depozone, where the round accumulating infill system was abruptly changed to westward fluvial-delta drainage system with the synchronous occurrence of an NNE-trending elongate trough since the early Campanian. The NNE-strike Great Xing'an Range acted as the forebulge uplift, missing the Upper Cretaceous. A thin saucer-shaped sag basin developed in the Hailar and Erlian basins during the late Campanian-Maastrichtian represents a back-bulge subsidence. Compressive deformation both in the western and central zones almost formed at the latest Cretaceous and weakened westward. Ancient counterparts of these four depozones can be identified in northeast China suggest that a foreland basin system was coupled with the coastal orogeny under a retro-arc setting during the Campanian-Maatrichtian of late Cretaceous, which is inferred to be the response of tectonic switch from West Pacific-type to Andean-type subduction along northeastern Asia.

  4. A CHARACEAN THALLUS WITH ATTACHED GYROGONITES AND ASSOCIATED FOSSIL CHAROPHYTES FROM THE MAASTRICHTIAN OF THE EASTERN PYRENEES (CATALONIA, SPAIN)(1).

    PubMed

    Villalba-Breva, Sheila; Martín-Closas, Carles

    2011-02-01

    The new species Clavatoraxis microcharophorus is described from the Lower Maastrichtian of the Eastern Pyrenees (Catalonia, Spain). Microchara sp. gyrogonites were found in anatomical connection with this thallus, attached to bract-cell rosettes and coated by a structural tunica, formed by an expanded bract cell. This is a feature unknown in extant characeans, which only display lime incrustations similar to tunicae in extremely alkaline and well-illuminated environments. This is the first time that a complete fossil characean is described. The attribution of characean vegetative remains to the genus Clavatoraxis shows that this genus is not exclusive of clavatoraceans as previously thought. The taphonomic study of C. microcharophorus sp. nov. and associated fossil charophytes, along with sedimentological and microfacies analyses, has enabled us to characterize the habitat of this species in the Maastrichtian lake of Vallcebre. They grew forming meadows, and their remains were deposited in the poorly oxygenated lake bottom, where they were well preserved. A number of other characeans and porocharaceans were living in shallower belts. This was the case for Peckichara sp. and Munieria grambasti in the freshwater lacustrine meadows. Another species, Feistiella malladae, was found parautochthonous in brackish lakes.

  5. The chronostratigraphic framework of the South-Pyrenean Maastrichtian succession reappraised: Implications for basin development and end-Cretaceous dinosaur faunal turnover

    NASA Astrophysics Data System (ADS)

    Fondevilla, Víctor; Dinarès-Turell, Jaume; Oms, Oriol

    2016-05-01

    The evolution of the end-Cretaceous terrestrial ecosystems and faunas outside of North America is largely restricted to the European Archipelago. The information scattered in this last area can only be integrated in a chronostratigraphic framework on the basis of robust age constraints and stratigraphy. Therefore, we have revisited the puzzling age calibration of the sedimentary infilling from the Isona sector in the Tremp syncline (South-Central Pyrenees), an area renowned for its rich Maastrichtian dinosaur fossil record. Aiming to shed light to existing controversial age determinations, we carried out a new magnetostratigraphic study along the ~ 420 m long Orcau and Nerets sections of that area. Our results reveal that most of the succession correlates to the early Maastrichtian (mostly chron C31r) in accordance to ages proposed by recent planktonic foraminifera biostratigraphy. The resulting chronostratigraphic framework of the entire Maastrichtian basin recorded in the Tremp syncline shows that a significant sedimentary hiatus of about 3 My characterizes most of the late Maastrichtian in the study area. This hiatus, related to an abrupt migration of the basin depocenter, is temporally close to similar hiatuses, decreases in sedimentary rates and facies shifts recorded in other southwestern European areas. The present chronologic framework sets the basis for a thorough assessment of end-Cretaceous terrestrial faunal turnover and extinction patterns, and the establishment of a more rigorous Pyrenean basin evolution analysis.

  6. Migrated hydrocarbons in exposure of Maastrichtian nonmarine strata near Saddle Mountain, lower Cook Inlet, Alaska

    USGS Publications Warehouse

    LePain, D.L.; Lillis, P.G.; Helmold, K.P.; Stanley, R.G.

    2012-01-01

    Magoon and others (1980) described an 83-meter- (272-foot-) thick succession of Maastrichtian (Upper Cretaceous) conglomerate, sandstone, mudstone, and coal exposed on the south side of an unnamed drainage, approximately 3 kilometers (1.8 miles) east of Saddle Mountain in lower Cook Inlet (figs. 1 and 2). The initial significance of this exposure was that it was the first reported occurrence of nonmarine rocks of this age in outcrop in lower Cook Inlet, which helped constrain the Late Cretaceous paleogeography of the area and provided important information on the composition of latest Mesozoic sandstones in the basin. The Saddle Mountain section is thought to be an outcrop analog for Upper Cretaceous nonmarine strata penetrated in the OCS Y-0097 #1 (Raven) well, located approximately 40 kilometers (25 miles) to the south–southeast in Federal waters (fig. 1). Atlantic Richfield Company (ARCO) drilled the Raven well in 1980 and encountered oil-stained rocks and moveable liquid hydrocarbons between the depths of 1,760 and 3,700 feet. Completion reports on file with the Bureau of Ocean Energy Management (BOEM; formerly Bureau of Ocean Energy Management, Regulation and Enforcement, and prior to 2010, U.S. Minerals Management Service) either show flow rates of zero or do not mention flow rates. A fluid analysis report on file with BOEM suggests that a wireline tool sampled some oil beneath a 2,010-foot diesel cushion during the fl ow test of the 3,145–3,175 foot interval, but the recorded fl ow rate was still zero (Kirk Sherwood, written commun., January 9, 2012). Further delineation and evaluation of the apparent accumulation was never performed and the well was plugged and abandoned. As part of a 5-year comprehensive evaluation of the geology and petroleum systems of the Cook Inlet forearc basin, the Alaska Division of Geological & Geophysical Surveys obtained a research permit from the National Park Service to access the relatively poorly understood

  7. The end-Cretaceous in the southwestern Tethys (Elles, Tunisia): orbital calibration of paleoenvironmental events before the mass extinction

    NASA Astrophysics Data System (ADS)

    Thibault, Nicolas; Galbrun, Bruno; Gardin, Silvia; Minoletti, Fabrice; Le Callonnec, Laurence

    2016-04-01

    An integrated study of magnetic mass susceptibility (MS), bulk stable isotopes and calcareous nannofossil paleoecological changes is undertaken on the late Maastrichtian of the Elles section, Tunisia, spanning the last ca. 1 Myr of the Cretaceous. A cyclostratigraphic analysis reveals the presence of Milankovitch frequencies and is used for proposal of two distinct orbital age models and to provide ages of important stratigraphic horizons, relative to the age of the Cretaceous-Paleogene boundary (K-PgB). Principal component analysis (PCA) performed on the nannofossil assemblage reveal two main factors, PCA1, mostly representing fluctuations of D. rotatorius, P. stoveri, Lithraphidites spp., Retecapsa spp., Staurolithites spp., Micula spp., and PCA2, mostly representing fluctuations of A. regularis, C. ehrenbergii, Micula spp., Rhagodiscus spp., W. barnesiae and Zeugrhabdotus spp. Variations in PCA1 and PCA2 match changes in bulk δ13C and δ18O, respectively, and suggest changes in surface-water fertility and temperatures and associated stress. The variations in abundances of high-latitude taxa and the warm-water species Micula murus and in bulk δ18O delineate fast changes in sea-surface paleotemperatures. As in many other sites, an end-Maastrichtian greenhouse warming is highlighted, followed by a short cooling and an additional warm pulse in the last 30 kyr of the Maastrichtian which has rarely been documented so far. Orbital tuning of the delineated climatic events is proposed following the two different age models. Calcareous nannofossil assemblages highlight a decrease in surface-water nutriency, but their species richness remains high through the latest Maastrichtian, indicating, in Tunisia, a weak impact of Deccan volcanism on calcareous nannoplankton diversity before the mass extinction.

  8. The Blake Nose Cretaceous-Paleogene (Florida Atlantic margin, ODP Leg 171B): an exemplar record of the Maastrichtian-Danian transition

    USGS Publications Warehouse

    Bellier, J.-P.; Marca, S.; Norris, R.D.; Kroon, D.; Klaus, A.; Alexander, I.T.; Bardot, L.P.; Barker, C.E.; Blome, C.D.; Clarke, L.J.; Erbacher, J.; Faul, K.L.; Holmes, M.A.; Huber, B.T.; Katz, M.E.; MacLeod, K.G.; Martinez-Ruiz, F. C.; Mita, I.; Nakai, M.; Ogg, James G.; Pak, D.K.; Pletsch, T.K.; ,; Shackleton, N.J.; Smit, J.; Ussler, W.; Watkins, D.K.; Widmark, J.; Wilson, P.A.

    1997-01-01

    During ODP Leg 171B, devoted to the analysis of the Blake Plateau margin in front of Florida, 16 holes have been drilled in 5 distinct sites. The sites have documented a sedimentary succession ranging in age from Aptian to Eocene. Emphasis has been put on critical periods, comprising the Paleocene-Eocene transition, the Cretaceous-Tertiary boundary which has been cored in excellent conditions, the middle Maastrichtian extinctions and the Albian anoxic episodes.

  9. The benthic fauna from the lower Maastrichtian chalk of Kronsmoor (Saturn quarry, northern Germany): composition and palaeoecologic implications

    NASA Astrophysics Data System (ADS)

    Engelke, Julia; Linnert, Christian; Mutterlose, Jörg; Wilmsen, Markus

    2017-04-01

    The Saturn quarry near Kronsmoor (northern Germany) offers an undisturbed section of upper Campanian to lower Maastrichtian chalks. The target interval of the DFG project "Biodiversity and plankton-benthos coupling: an integrated ecosystem analysis from the Late Cretaceous Chalk" is focused on the lower Maastrichtian Belemnella obtusa Zone to mid-Belemnella sumensis Zone, i.e. to the uppermost Kronsmoor and lowermost Hemmoor formations. In this interval, a conspicuous increase in macrofossil abundance without apparent lithofacies changes has been observed and the project intends to integrate planktic, benthic and geochemical proxies for a comprehensive understanding of the Chalk Sea ecosystem. The aim of this study is the analysis of the benthic community. In a first step, the benthic body fossils of the c. 25-m-thick section were semi-quantitatively studied based on a collection of more than 1,000 specimens. Two successive benthic macrofossil assemblages were recognised: the lower interval (upper part of the Kronsmoor Formation, B. obtusa Zone) is characterized by low abundances, only about 100 macroinvertebrates were collected, mostly irregular and regular echinoids, brachiopods and crinoids. The upper interval (B. sumensis Zone) shows an eight times higher macroinvertebrate abundance and a conspicuous dominance of brachiopods, increasing from only 30 to over 500 specimens. In order to quantify the observed qualitative palaeoecological changes, 33 bulk samples of about 6 kg each were retrieved in a distance of c. 0.75 m. The bulk samples were frozen and thawed, washed and sieved in different sizes. The fraction 500 μm-1 mm and >1 mm were picked, sorted and counted. A diverse assemblage of bryozoans, foraminifers, shell fragments of brachiopods and bivalves, spines and test fragments of different echinoid taxa, parts of asteroids and ophiuroids, sponge debris, crinoids and small serpulids, is present. Reduced abundances in the lower part and generally higher

  10. Geochemistry and petrology of altered peridotite overlain by Maastrichtian to Miocene sediments in the SE Samail Ophiolite, Oman

    NASA Astrophysics Data System (ADS)

    de Obeso, J. C.; Kelemen, P. B.

    2015-12-01

    In the southeastern Oman Mountains the mantle section of the Samail ophiolite is unconformably capped by large units of Maastrichtian to Miocene, shallow marine limestones. Oceanic crust and upper mantle were thrust onto the Arabian continental margin from ca 96 to 80 Ma. Subaerial erosion locally removed the crustal section and exposed peridotite to weathering. A Maastrichtian transgression led to deposition of Late Cretaceous to Miocene, shallow marine limestones and shales above the unconformity. Near the town of Fins, a deep canyon exposes the unconformity and underlying, altered mantle peridotite. A striking series of clastic dikes of grey, micritic limestone extends across the unconformity, up to 10 meters down into the peridotite. Tips of these dikes are choked with angular peridotite blocks. Deeper, the peridotite is cut by a spectacular grid of carbonate-serpentine veins with abundant vugs. The peridotite matrix has high concentrations of calcium and small enrichments of silica compared to the Oman protolith, resulting from reaction with a hydrous fluid derived from seawater equilibrated with the overlying sediments. δ13C from -1.3-0.61 per mil (VPDB) and δ18O between 22.2 to 28 per mil (SMOW) are similar to values in the overlying sediments (Schluter et al., Facies 2008). Clumped isotope thermometry on calcite crystals in veins cutting the peridotite outcrops indicate crystallization at 25-60 °C. Sediment thickness reconstructions place the pressure of alteration between 300-600 bars. 87Sr/86Sr values of 0.7078 and 0.7079 correspond to seawater Sr isotope ratios at the Cretaceous-Tertiary boundary, which is present in the overlying limestones about 50 meters above the unconformity. This suggests that the veins in the peridotite formed at about 60 Ma, or that their parental fluid was in Sr isotope exchange equilibrium with 60 Ma sediments. Reaction path modeling of carbonated saturated seawater and peridotite reproduces the observed vein mineral

  11. Kepler's Orbit

    NASA Image and Video Library

    Kepler does not orbit the Earth, rather it orbits the Sun in concert with the Earth, slowly drifting away from Earth. Every 61 Earth years, Kepler and Earth will pass by each other. Throughout the ...

  12. Orbital cellulitis

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/001012.htm Orbital cellulitis To use the sharing features on this page, please enable JavaScript. Orbital cellulitis is an infection of the fat and muscles ...

  13. The genus Krithe (Ostracoda) from the Campanian and Maastrichtian (Upper Cretaceous) of the northern US Gulf Coastal Plain

    USGS Publications Warehouse

    Puckett, T.M.

    1997-01-01

    The ostracode genus Krithe is one of the most common genera in the Upper Cretaceous (late Santonian to Maastrichtian) deposits of the northern Gulf Coastal Plain of North America. Although it is never abundant, the genus occurs in sediments that were deposited under a wide range of palaeoenvironments, including nearshore sandy marls to offshore, nearly pure, chalk. The taxonomy of this taxon has been problematical, and what is herein considered to be a single species, K. cushmani, has been referred to in the literature under five different names. Two morphotypes were observed: relatively large individuals with 'mushroom'-shaped vestibules collected from chalk, and smaller individuals with pocket-shaped vestibules collected from nearshore deposits. Species of Krithe have been hypothesized to be useful in estimating dissolved oxygen concentration in ancient ocean floors, based on details of their morphology. Whereas the relationship between size and environment corroborates with previous predictions (larger individuals live in deeper water), the morphology of the vestibules contradicts predictions (the larger vestibules occur in the nearshore deposits and the smaller, more constricted vestibules occur in the chalk). A causal relationship between environment and morphology is discussed.

  14. A new ceratopsian dinosaur from the Javelina Formation (Maastrichtian) of West Texas and implications for chasmosaurine phylogeny.

    PubMed

    Wick, Steven L; Lehman, Thomas M

    2013-07-01

    Bravoceratops polyphemus gen. et sp. nov. is a large chasmosaurine ceratopsid from the lowermost part of the Javelina Formation (early Maastrichtian) of Big Bend National Park, TX, USA. B. polyphemus has a distinctive narrow snout, a long fenestrate frill, and a fan-shaped median parietal bar with a midline epiparietal on its posterior margin, as well as a symmetrical depression on its dorsal surface at the nexus of the parietal rami. This depression is interpreted to be the attachment point for a second midline epiparietal. This parietal morphology is distinct from that exhibited by Anchiceratops or Pentaceratops. The posterior midline epiparietal in B. polyphemus and its bifurcated quadratojugal-squamosal joint are features shared with the most derived chasmosaurines, Torosaurus and Triceratops. The combination of primitive and derived traits exhibited by B. polyphemus, and its stratigraphic position, is compatible with the gradual transition from basal, to intermediate, to derived chasmosaurines observed throughout the western interior of North America, and with phylogenetic analysis, which suggests that Bravoceratops may be closely related to Coahuilaceratops.

  15. A new ceratopsian dinosaur from the Javelina Formation (Maastrichtian) of West Texas and implications for chasmosaurine phylogeny

    NASA Astrophysics Data System (ADS)

    Wick, Steven L.; Lehman, Thomas M.

    2013-07-01

    Bravoceratops polyphemus gen. et sp. nov. is a large chasmosaurine ceratopsid from the lowermost part of the Javelina Formation (early Maastrichtian) of Big Bend National Park, TX, USA. B. polyphemus has a distinctive narrow snout, a long fenestrate frill, and a fan-shaped median parietal bar with a midline epiparietal on its posterior margin, as well as a symmetrical depression on its dorsal surface at the nexus of the parietal rami. This depression is interpreted to be the attachment point for a second midline epiparietal. This parietal morphology is distinct from that exhibited by Anchiceratops or Pentaceratops. The posterior midline epiparietal in B. polyphemus and its bifurcated quadratojugal-squamosal joint are features shared with the most derived chasmosaurines, Torosaurus and Triceratops. The combination of primitive and derived traits exhibited by B. polyphemus, and its stratigraphic position, is compatible with the gradual transition from basal, to intermediate, to derived chasmosaurines observed throughout the western interior of North America, and with phylogenetic analysis, which suggests that Bravoceratops may be closely related to Coahuilaceratops.

  16. A Comparison of "Ice-House" (Modern) and "Hot-House" (Maastrichtian) Drainage Systems: the Implications of Large-Scale Changes in the Surface Hydrological Scheme

    NASA Astrophysics Data System (ADS)

    Markwick, P. J.; Crossley, R.; Valdes, P. J.

    2002-12-01

    A GIS analysis of modern and Maastrichtian (Late Cretaceous) drainage systems has been made in order to investigate the potential differences between the surface hydrology of "ice-house" and "hot-house" worlds and how this might be reflected in the geological record. Because of the importance of CO2 concentrations for generating "hot-house" climates this study also has implications for potential future changes in the climate system. For the modern system we have utilized global maps of observed river systems, the Hydro1K digital dataset, observations of freshwater and sediment fluxes from recording stations, and modern day climate models and observations. For the Maastrichtian we have compiled a detailed global paleogeographic map and geological database (based on earlier work by the Paleogeographic Atlas Project, University of Chicago) that has been used to generate a paleo-DEM using the suite of hydrological tools in ArcGIS, complete with reconstructed river systems and drainage basins. This forms the primary boundary condition for a coupled ocean-atmosphere experiment using the HadCM3 model, with atmospheric CO2 set at 4 x pre-industrial levels. The results indicate a Maastrichtian world dominated by high sea surface temperatures (as high as 30-35 C in the tropics), and a consequently greatly enhanced hydrological cycle when compared with the Present. Globally, modeled Maastrichtian precipitation and evaporation are 1.5x that for the Present, with a 2.5x increase in total runoff. These changes are not evenly distributed, either spatially or seasonally, and therefore a detailed consideration of the paleogeography and paleo-drainage is essential, as these changes have a major influence on the distribution of vegetation and freshwater and sediment fluxes. For example, the Maastrichtian Tethyan monsoon, though less intense than noted for other modeled Mesozoic intervals, nonetheless dominates the seasonal distribution of precipitation and runoff over Saharan and

  17. Paleocene and Maastrichtian calcareous nannofossils from clasts in Pleistocene glaciomarine muds from the northern James Ross Basin, western Weddell Sea, Antarctica

    USGS Publications Warehouse

    Kulhanek, D.K.

    2007-01-01

    Site NBP0602A-9, drilled during the SHALDRIL II cruise of the RV/IB Nathaniel B. Palmer, includes two holes located in the northern James Ross Basin in the western Weddell Sea, very close to the eastern margin of the Antarctic Peninsula. Sediment from both holes consists of very dark grey, pebbly, sandy mud, grading to very dark greenish grey, pebbly, silty mud in the lower 2.5 m of the second hole. In addition to abundant pebbles found throughout the cores, both holes contain numerous sedimentary clasts. Biostratigraphic analysis of diatom assemblages from the glaciomarine muds yields rare to few, poorly preserved diatoms. The mixed assemblage consists mostly of extant species, but also includes reworked taxa that range to the Miocene. The absence of Rouxia spp., however, suggests the sediment is late Pleistocene in age. The sedimentary clasts, on the other hand, are nearly barren of diatoms, but contain rare, moderately to well-preserved calcareous nannofossils. The clasts contain three distinct assemblages. Two clasts are assigned an early Maastrichtian age based on the presence of Biscutum magnum and Nephrolithus corystus, while one clast yields a late Maastrichtian age based on the presence of Nephrolithus frequens. These samples also contain other characteristic Late Cretaceous species, including Biscutum notaculum, Cribrosphaerella daniae, Eiffellithus gorkae, Kamptnerius magnificus, and Prediscosphaera bukryi. Two samples yield an early Paleocene assemblage dominated by Hornibrookina teuriensis. The Maastrichtian assemblages are similar to those found in the López de Bertodano Formation on Seymour and Snow Hill Islands, making it the likely source area for the Cretaceous clast material. Although no calcareous nannofossils have been reported from Paleocene formations on these islands, the occurrence of calcareous foraminifers suggests other calcareous plankton may be present; thus the Paleocene clasts likely also originated from the Seymour Island area.

  18. The Hot Orbit: Orbital Cellulitis

    PubMed Central

    Chaudhry, Imtiaz A.; Al-Rashed, Waleed; Arat, Yonca O.

    2012-01-01

    Orbital cellulitis is an uncommon condition previously associated with severe complications. If untreated, orbital cellulitis can be potentially sight and life threatening. It can affect both adults and children but has a greater tendency to occur in the pediatric age group. The infection most commonly originates from sinuses, eyelids or face, retained foreign bodies, or distant soources by hematogenous spread. It is characterized by eyelid edema, erythema, chemosis, proptosis, blurred vision, fever, headache, and double vision. A history of upper respiratory tract infection prior to the onset is very common especially in children. In the era prior to antibiotics, vision loss from orbital cellulitis was a dreaded complication. Currently, imaging studies for detection of orbital abcess, the use of antibiotics and early drainage have mitigated visual morbidity significantly. The purpose of this review is to describe current investigative strategies and management options in the treatment of orbital cellulitis, establish their effectiveness and possible complications due to late intervention. PMID:22346113

  19. Inflammation of the Orbit

    MedlinePlus

    ... Cavernous Sinus Thrombosis Inflammation of the Orbit Orbital Cellulitis Preseptal Cellulitis Tumors of the Orbit Any or all of ... Cavernous Sinus Thrombosis Inflammation of the Orbit Orbital Cellulitis Preseptal Cellulitis Tumors of the Orbit NOTE: This ...

  20. A new species of Allodaposuchus (Eusuchia, Crocodylia) from the Maastrichtian (Late Cretaceous) of Spain: phylogenetic and paleobiological implications

    PubMed Central

    Blanco, Alejandro; Fortuny, Josep; Vicente, Alba; Luján, Àngel H.; García-Marçà, Jordi Alexis

    2015-01-01

    Background. The Late Cretaceous is a keystone period to understand the origin and early radiation of Crocodylia, the group containing all extant lineages of crocodilians. Among the taxa described from the latest Cretaceous of Europe, the genus Allodaposuchus is one of the most common but also one of the most controversial. However, because of its fragmentary record, several issues regarding its phylogenetic emplacement and its ecology remain unsolved or unknown. The discovery of a single specimen attributed to Allodaposuchus, represented by both cranial and postcranial remains, from the Casa Fabà site (Tremp Basin, NE Spain) in the lower red unit of the Tremp Fm. (early Maastrichtian, Late Cretaceous) offers a unique opportunity to deepen in the phylogenetic relationships of the group and its ecological features. Methods. The specimen is described in detail, and CT scan of the skull is performed in order to study the endocranial morphology as well as paratympanic sinuses configuration. In addition, myological and phylogenetic analyses are also carried out on the specimen for to shed light in ecological and phylogenetic issues, respectively. Results. The specimen described herein represents a new species, Allodaposuchus hulki sp. nov., closely related to the Romanian A. precedens. The CT scan of the skull revealed an unexpected paratympanic sinuses configuration. Allosaposuchus hulki exhibits an “anterodorsal tympanic sinus” not observed in any other extant or extinct crocodilian. The caudal tympanic recesses are extremely enlarged, and the expanded quadratic sinus seems to be connected to the middle-ear channel. Phylogenetic analyses confirm the emplacement of the informal taxonomic group ‘Allodaposuchia’ at the base of Crocodylia, being considered the sister group of Borealosuchus and Planocraniidae. Discussion. Although this is a preliminary hypothesis, the unique paratympanic configuration displayed by A. hulki suggests that it could possess a high

  1. A new species of Allodaposuchus (Eusuchia, Crocodylia) from the Maastrichtian (Late Cretaceous) of Spain: phylogenetic and paleobiological implications.

    PubMed

    Blanco, Alejandro; Fortuny, Josep; Vicente, Alba; Luján, Àngel H; García-Marçà, Jordi Alexis; Sellés, Albert G

    2015-01-01

    Background. The Late Cretaceous is a keystone period to understand the origin and early radiation of Crocodylia, the group containing all extant lineages of crocodilians. Among the taxa described from the latest Cretaceous of Europe, the genus Allodaposuchus is one of the most common but also one of the most controversial. However, because of its fragmentary record, several issues regarding its phylogenetic emplacement and its ecology remain unsolved or unknown. The discovery of a single specimen attributed to Allodaposuchus, represented by both cranial and postcranial remains, from the Casa Fabà site (Tremp Basin, NE Spain) in the lower red unit of the Tremp Fm. (early Maastrichtian, Late Cretaceous) offers a unique opportunity to deepen in the phylogenetic relationships of the group and its ecological features. Methods. The specimen is described in detail, and CT scan of the skull is performed in order to study the endocranial morphology as well as paratympanic sinuses configuration. In addition, myological and phylogenetic analyses are also carried out on the specimen for to shed light in ecological and phylogenetic issues, respectively. Results. The specimen described herein represents a new species, Allodaposuchus hulki sp. nov., closely related to the Romanian A. precedens. The CT scan of the skull revealed an unexpected paratympanic sinuses configuration. Allosaposuchus hulki exhibits an "anterodorsal tympanic sinus" not observed in any other extant or extinct crocodilian. The caudal tympanic recesses are extremely enlarged, and the expanded quadratic sinus seems to be connected to the middle-ear channel. Phylogenetic analyses confirm the emplacement of the informal taxonomic group 'Allodaposuchia' at the base of Crocodylia, being considered the sister group of Borealosuchus and Planocraniidae. Discussion. Although this is a preliminary hypothesis, the unique paratympanic configuration displayed by A. hulki suggests that it could possess a high

  2. Extraterrestrial chromite in latest Maastrichtian and Paleocene pelagic limestone at Gubbio, Italy: The flux of unmelted ordinary chondrites

    NASA Astrophysics Data System (ADS)

    Cronholm, Anders; Schmitz, Birger

    The distribution of sediment-dispersed extraterrestrial (ordinary chondritic) chromite (EC) grains (>63 μm) has been studied across the latest Maastrichtian and Paleocene in the Bottaccione Gorge section at Gubbio, Italy. This section is ideal for determining the accumulation rate of EC because of its condensed nature and well-constrained sedimentation rates. In a total of 210 kg of limestone representing eight samples of 14-28 kg distributed across 24 m of the Bottaccione section, only 6 EC grains were found (an average of 0.03 EC grains kg-1). In addition, one probable pallasitic chromite grain was found. No EC grains could be found in two samples at the Cretaceous-Tertiary (K-T) boundary, which is consistent with the K-T boundary impactor being a carbonaceous chondrite or comet low in chromite. The average influx of EC to Earth is calculated to ˜0.26 grain m-2 kyr-1. This corresponds to a total flux of ˜200 tons of extraterrestrial matter per year, compared to ˜30,000 tons per year, as estimated from Os isotopes in deep-sea sediments. The difference is explained by the EC grains representing only unmelted ordinary chondritic matter, predominantly in the size range from ˜0.1 mm to a few centimeters in diameter. Sedimentary EC grains can thus give important information on the extent to which micrometeorites and small meteorites survive the passage through the atmosphere. The average of 0.03 EC grain kg-1 in the Gubbio limestone contrasts with the up to ˜3 EC grains kg-1 in mid-Ordovician limestone that formed after the disruption of the L chondrite parent body in the asteroid belt at ˜470 Ma. The two types of limestone were deposited at about the same rate, and the difference in EC abundance gives support for an increase by two orders of magnitude in the flux of chondritic matter directly after the asteroid breakup.

  3. Geology and taphonomy of the L'Espinau dinosaur bonebed, a singular lagoonal site from the Maastrichtian of South-Central Pyrenees

    NASA Astrophysics Data System (ADS)

    Fondevilla, V.; Vicente, A.; Battista, F.; Sellés, A. G.; Dinarès-Turell, J.; Martín-Closas, C.; Anadón, P.; Vila, B.; Razzolini, N. L.; Galobart, À.; Oms, O.

    2017-06-01

    The L'Espinau site is a dinosaur bonebed from the Upper Cretaceous of the South-Central Pyrenees (north-eastern Spain) that have provided hundreds of bone remains attributed to hadrosauroids, together with a rich assemblage of herpetofauna, fish and microflora. Magnetostratigraphy calibrated the site with the early late Maastrichtian, and the combined sedimentology, stable isotope geochemistry and palaeoecology revealed that this fossil site formed in a lagoon, in which a mixed freshwater-brackish palaeoenvironment was developed. This setting displays a south-north charophyte zonation from freshwater (Clavator brachycerus-dominated assemblage) to brackish or eurihaline conditions (Feistiella malladae-dominated assemblage), revealing a palaeoenvironment change towards the coast. Sedimentology and taphonomy (bidirectional arrangement of long bones, abrasion and disarticulation) indicate that the L'Espinau site is the result of a cohesive mass flow event originated very close to the sea. This process entrained and mixed fauna from both the terrestrial and the brackish/marine environment of a lagoon. An increasing of the water runoff (e.g. by intense rainfall) reworking poorly consolidated sediments is considered here as the most probable triggering mechanism. Mass flow-hosted bonebeds are commonly linked to fluvial palaeoenvironments, so our study case is a rare example of bones accumulating near the sea. This study adds evidence that hadrosauroids inhabited littoral environments during the Maastrichtian in the southern Pyrenean area.

  4. Orbital pseudotumor

    MedlinePlus

    ... Goodlick TA, Kay MD, Glaser JS, Tse DT, Chang WJ. Orbital disease and neuro-ophthalmology. In: Tasman ... 423. Review Date 8/20/2016 Updated by: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La ...

  5. Orbital Myiasis

    PubMed Central

    Khataminia, Gholamreza; Aghajanzadeh, Roja; Vazirianzadeh, Babak; Rahdar, Mahmoud

    2011-01-01

    Purpose To present a case of massive orbital myiasis. Case Report An 87-year-old debilitated woman suffering from left ocular pain of four days’ duration presented with a severely necrotized left orbit and several attached live larvae. The upper and lower eyelids and the eyeball were completely destroyed. She had history of eyelid surgery in the same eye due to a skin lesion, apparently some type of skin cancer, 15 years before. The larvae were identified as Chrysomya bezziana (Diptera: Calliphoridae) or old world screwworm fly. Conclusion Infestation of ocular and orbital tissues by fly larvae (ophthalmomyiasis) progresses rapidly and can completely destroy orbital tissues within days, especially in patients with poor general health. Treatment consists of removal of the larvae and surgical debridement. PMID:22454736

  6. Orbiter's Skeleton

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The structure of NASA's Mars Reconnaissance Orbiter spacecraft is constructed from composite panels of carbon layers over aluminum honeycomb, lightweight yet strong. This forms a basic structure or skeleton on which the instruments, electronics, propulsion and power systems can be mounted. The propellant tank is contained in the center of the orbiter's structure. This photo was taken at Lockheed Martin Space Systems, Denver, during construction of the spacecraft.

  7. Orbital Debris

    NASA Technical Reports Server (NTRS)

    Kessler, D. J. (Compiler); Su, S. Y. (Compiler)

    1985-01-01

    Earth orbital debris issues and recommended future activities are discussed. The workshop addressed the areas of environment definition, hazards to spacecraft, and space object management. It concluded that orbital debris is a potential problem for future space operations. However, before recommending any major efforts to control the environment, more data are required. The most significant required data are on the population of debris smaller than 4 cm in diameter. New damage criteria are also required. When these data are obtained, they can be combined with hypervelocity data to evaluate the hazards to future spacecraft. After these hazards are understood, then techniques to control the environment can be evaluated.

  8. Nuclear orbiting

    SciTech Connect

    Shapira, D.

    1988-01-01

    Nuclear orbiting following collisions between sd and p shell nuclei is discussed. The dependence of this process on the real and imaginary parts of the nucleus-nucleus potential is discussed, as well as the evolution of the dinucleus toward a fully equilibrated fused system. 26 refs., 15 figs.

  9. Mineralogy and Geochemistry of Upper Maastrichtian-Middle Eocene Clay - Rich Volcano - Sedimentary Units from South-Eastern of Elazıg Basin (Eastern Turkey)

    NASA Astrophysics Data System (ADS)

    Akkoca, Dicle Bal; Daş, Burhan

    2017-04-01

    Clay-rich Hazar-Maden volcano-sediments were deposited along the southern branch of the Neotethys Ocean margin during Upper Maastrichtian - Middle Eocene times. Mineralogy and geochemistry of Hatunkoy section from the south - easthern of Elazıg were studied by X-ray powder diffraction (XRD), ICP-AES, ICP-MS. The Upper Jurassic - Lower Cretaceous Guleman Ophiolites, Upper Maastrichtian - Middle Eocene Hazar Group, the Middle Eocene Maden Group, Pliocene-Quaternary alluvial deposits are situated in the study area. The Guleman Ophiolites are composed of dunite, harzburgite with podiform chromite, alternating dunite-wherlite, clinopyroxenite banded gabbro, quartz gabbro/diorite or plagiogranite and volcanites. The Hazar Group consists of limestone and interbedded shale and sandstone. The Maden Group has a complex lithology consisting of limestones, red-green clayey limestones, sandstone, agglomerate, tuffs, reddish mudstone and basaltic-andesitic pillow lavas. Mineralogy and geochemistry of Hazar and Maden Group samples are similar in Hatunkoy section. All samples consist of clay minerals (chlorite, illite), calcite, quartz, and feldspar. SiO2, Al2O3, Fe2O3, K2O contents show that samples are convenient with Fe shales and shales. The ratios of Zr/TiO2, Th/Sc, Zr/Sc, Y/Ni-Cr/V, Al/(Al+Fe+Mn) show dominance of neutral-basic volcanism in the area. Rare earth elements (REE) concentrations of samples are normalized to chondrite values and it is determined that low light rare earth elements (LREEs) are enriched in comparison to high rare earth elements (HREEs), and the absence of Eu anomalies shows that our samples are generally neutral-basic in composition. REE of samples were compared with North American shale composite (NASC), European shale (ES) and Post-Archean Australian shale (PAAS). Elements are not in concurrence with these compositions. Key Words:Mineralogy, Geochemistry, Volcano sedimentary Units, Eastern Turkey.

  10. Eye and orbit ultrasound

    MedlinePlus

    Echography - eye orbit; Ultrasound - eye orbit; Ocular ultrasonography; Orbital ultrasonography ... ophthalmology department of a hospital or clinic. Your eye is numbed with medicine (anesthetic drops). The ultrasound ...

  11. Orbit analysis

    SciTech Connect

    Michelotti, L.

    1995-01-01

    The past fifteen years have witnessed a remarkable development of methods for analyzing single particle orbit dynamics in accelerators. Unlike their more classic counterparts, which act upon differential equations, these methods proceed by manipulating Poincare maps directly. This attribute makes them well matched for studying accelerators whose physics is most naturally modelled in terms of maps, an observation that has been championed most vigorously by Forest. In the following sections the author sketchs a little background, explains some of the physics underlying these techniques, and discusses the best computing strategy for implementing them in conjunction with modeling accelerators.

  12. Orbital Winch

    NASA Technical Reports Server (NTRS)

    Hoyt, Robert (Inventor); Slostad, Jeffrey T. (Inventor); Frank, Scott (Inventor); Barnes, Ian M. (Inventor)

    2016-01-01

    Orbital winch having: lower and upper frames; spool having upper and lower flanges with lower flange attached to lower frame; axial tether guide mounted to upper frame; secondary slewing ring coaxial with spool and rotatably mounted to upper frame, wherein secondary slewing ring's outer surface has gearing; upper tether guide mounted to inner surface of secondary slewing ring; linear translation means having upper end mounted to upper frame and lower end mounted on lower frame; primary slewing ring rotatably mounted within linear translation means allowing translation axially between flanges, wherein primary slewing ring's outer surface has gearing; lower tether guide mounted on primary slewing ring's inner surface; pinion rod having upper end mounted to upper frame and lower end mounted to lower frame, wherein pinion rod's teeth engage primary and secondary slewing rings' outer surface teeth; and tether passing through axial, upper, and lower tether guides and winding around spool.

  13. Orbital liposarcoma.

    PubMed

    Borbolla-Pertierra, A M; Morales-Baños, D R; Martínez-Nava, L R; Garrido-Sánchez, G A; López-Hernández, C M; Velasco-Ramos, P

    2017-02-01

    The case is presented of a 46-year-old male with right eye proptosis and conjunctival hyperaemia, of 18 months onset. A well-defined intraconal mass was found in the computed tomography. In magnetic resonance this was hypo-intense on T1, enhanced with gadolinium and hyperintense on T2. Excisional biopsy was performed, which was reported as a well-differentiated liposarcoma in the histopathology study. Liposarcoma is a malignant adipose tissue tumour. It is very rare in the orbit, with 5 histological types, the most common being myxoid. The treatment of choice is wide surgical excision and may be accompanied with radiotherapy. As it is an infiltrative tumour, It has a high rate of recurrence. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Un ptérosaure azhdarchidé dans le Crétacé supérieur de Cruzy (Hérault, France)

    NASA Astrophysics Data System (ADS)

    Buffetaut, Eric

    2001-09-01

    Pterosaurs were hitherto represented in the abundant and varied Late Campanian-Early Maastrichtian vertebrate assemblages of southern France by very scanty remains, which did not allow an identification at the family level. An incomplete cervical vertebra from a locality of that age at Cruzy (Hérault, southern France) is described and identified as belonging to an azhdarchid pterosaur with an estimated wingspan of about 3 m.

  15. Paleoenvironmental interpretation of an ancient Arctic coastal plain: Integrated paleopedology and palynology from the Late Cretaceous (Maastrichtian) Prince Creek Formation, North Slope, Alaska, USA

    NASA Astrophysics Data System (ADS)

    McCarthy, P. J.; Flaig, P. P.; Fiorillo, A. R.

    2010-12-01

    The Cretaceous (Early Maastrichtian), dinosaur-bearing Prince Creek Formation, North Slope, Alaska, records high-latitude, alluvial sedimentation and soil formation on a low-lying, coastal plain during a greenhouse phase in Earth history. This study combines outcrop observations, micromorphology, geochemistry, and palynological analyses of paleosols in order to reconstruct local paleoenvironments of weakly developed, high-latitude coastal plain soils. Sediments of the Prince Creek Fm. include quartz- and chert-rich sandstone channels, and floodplains containing organic-rich siltstone and mudstone, carbonaceous shale, coal and ashfall deposits. Vertically stacked horizons of blocky-to-platy, drab-colored mudstone and siltstone with carbonaceous root-traces and mottled aggregates alternating with sandy units indicate that the development of compound and cumulative, weakly-developed soils on floodplains alternated with overbank alluviation and deposition on crevasse splay complexes on floodplains . Soil formation occurred on levees, point bars, crevasse splays and along the margins of floodplain lakes, ponds, and swamps. Soil-forming processes were interrupted by repeated deposition of sediment on top of soil profiles by flooding of nearby channels. Alluviation is evidenced by thin (<0.5 m) sand and silt horizons within soil profiles, along with common pedorelicts, papules, and fluctuations with depth in a variety of molecular ratios. Carbonaceous organic matter and root-traces, Fe-oxide depletion coatings, and zoned peds suggest periodic waterlogging, anoxia and gleying. In contrast, Fe-oxide mottles, ferruginous and manganiferous segregations, burrows, and rare illuvial clay coatings suggest recurring oxidation and periodic drying out of some soils. Jarosite mottles and halos, and rare pyrite and gypsum found in some distal paleosols implies a marine influence at the distal margins of the coastal plain. Biota including Peridinioid dinocysts, brackish and freshwater

  16. Amphibian, reptilian, and avian remains from the Fox Hills Formation (Maastrichtian): Shoreline and estuarine deposits of the Pierre Sea in south-central North Dakota

    USGS Publications Warehouse

    Hoganson, J.W.; Erickson, J.M.; Holland, F.D.

    2007-01-01

    Although vertebrate fossils, except for fish, are not common in the Maastrichtian Fox Hills Formation, amphibian, reptilian, and avian remains have been recovered at several localities in south-central North Dakota from shoreline facies of the retreating Pierre-Fox Hills seaway. This mixed fauna of aquatic, terrestrial, and marine taxa provides insight into the composition of coastal communities and habitats at the interface between the Hell Creek delta and the Western Interior Seaway. The delta-platform aquatic paleocommunity is represented by the efficient swimming salamanders Opistho- trition kayi and Lisserpeton bairdi, the carnivorous soft-shelled turtle "Aspideretes" sensu lato, the underwater piscivorous predator Champsosaurus laramiensis, and the large, predatory crocodile IBorealosuchus. Terrestrial areas were inhabited by the tortoise-like Basilemys and the predatory dinosaurs Tyrannosaurus and cf. Saurornit- holestes. Birds occupied niches in the warm-temperate to subtropical, forested delta platform and shoreline areas. These nonmarine taxa in the Fox Hills Formation indicate that the geographic range of these animals extended to shoreline areas of the Western Interior Seaway. The toxochelyid turtle Lophochelys and the ambush predators Mosasaurus dekayi and IPlioplatecarpus resided in the shallow marine and estuarine habitats. These taxa and marine fish taxa reported earlier indicate that normal marine conditions in south- central North Dakota persisted into the latest Late Cretaceous in comparison with coeval Hell Creek Formation sites more distal from the Western Interior Seaway. ?? 2007 The Geological Society of America. All rights reserved.

  17. A new species of Ischyodus (Chondrichthyes: Holocephali: Callorhynchidae) from Upper Maastrichtian Shallow marine facies of the Fox Hills and Hell Creek Formations, Williston basin, North Dakota, USA

    USGS Publications Warehouse

    Hoganson, J.W.; Erickson, J.M.

    2005-01-01

    A new species of chimaeroid, Ischyodus rayhaasi sp. nov., is described based primarily upon the number and configuration of tritors on palatine and mandibular tooth plates. This new species is named in honour of Mr Raymond Haas. Fossils of I. rayhaasi have been recovered from the Upper Maastrichtian Fox Hills Formation and the Breien Member and an unnamed member of the Hell Creek Formation at sites in south-central North Dakota and north-central South Dakota, USA. Ischyodus rayhaasi inhabited shallow marine waters in the central part of the Western Interior Seaway during the latest Cretaceous. Apparently it was also present in similar habitats at that time in the Volga region of Russia. Ischyodus rayhaasi is the youngest Cretaceous species Ischyodus known to exist before the Cretaceous/Tertiary extinction, and the species apparently did not survive that event. It was replaced by Ischyodus dolloi, which is found in the Paleocene Cannonball Formation of the Williston Basin region of North Dakota and is widely distributed elsewhere. ?? The Palaeontological Association.

  18. Orbiter/launch system

    NASA Technical Reports Server (NTRS)

    Jackson, L. R.; Weidner, J. P.; Small, W. J.; Martin, J. A. (Inventor)

    1981-01-01

    The system includes reusable turbojet propelled booster vehicles releasably connected to a reusable rocket powered orbit vehicle. The coupled orbiter-booster combination takes off horizontally and ascends to staging altitude and speed under booster power with both orbiter and booster wings providing lift. After staging, the booster vehicles fly back to Earth for horizontal landing and the orbiter vehicle continues ascending to orbit.

  19. High-resolution Campanian-Maastrichtian carbon and oxygen stable isotopes of bulk-rock and skeletal components: palaeoceanographic and palaeoenvironmental implications for the Boreal shelf sea

    NASA Astrophysics Data System (ADS)

    Wilmsen, Markus; Niebuhr, Birgit

    2017-03-01

    A high-resolution latest Early Campanian to Early Maastrichtian carbon and oxygen stable isotope record from the northern German Boreal shelf sea based on 537 analyses of co-occurring belemnites, brachiopods, inoceramids, oysters, and bulk rock samples is presented. All samples are precisely related to their stratigraphic, systematic and facies backgrounds and form an integrated, nearly 10-myr-long dataset with considerable palaeoenvironmental and palaeoceanographical implications. Petrographic studies indicate that low-magnesium calcitic coccoliths and calcispheres (i.e., planktic carbonate) predominate the bulk-rock data (marl-limestone rhythmites and chalks), thus representing a sea-surface water signal, and that only minor diagenetic alteration of the carbonate muds took place. Based on TL and CL microscopy, the investigated belemnites are extraordinarily well preserved, which may in part be explained by their early diagenetic surficial silicification (container effect), while the other macroinvertebrate groups are all less well preserved. The (plankton-dominated) δ13C values of the marl-limestone rhythmites and chalks (+1.1 to +2.5 ‰), recording a surface water signal, compare well with the δ18C data of inoceramids while δ13Cbrach. values (+1.5 to +3.0 ‰) are heavier than the bulk rock data. The large variation in the δ13Cbel. (-0.1 to +3.6 ‰) is attributed to isotopic disequilibrium of the biogenic carbonate formed by the belemnite animal. The bulk rock δ18O values show a remarkable low scatter, supporting petrographic observation of only minor diagenetic stabilisation/cementation, and can be approximated with northern German shelf sea-surface temperatures of ca. 20°C for the Late Campanian (ca. -2 ‰ δ18O), being slightly cooler during the Early Maastrichtian. The δ18O values of the belemnite rostra are even less variable and quite rich in heavier 18O (-0.7 to +0.6 with a mean of -0.1 ‰ δ18Obel.) in comparison to bulk rock and other

  20. Absolute paleobathymetry of Upper Cretaceous chalks based on ostracodes - Evidence from the Demopolis Chalk (Campanian and Maastrichtian) of the northern Gulf Coastal Plain

    SciTech Connect

    Puckett, T.M. )

    1991-05-01

    The presence of abundant and diverse sighted ostracodes in chalk and marl of the Demopolis Chalk (Campanian and Maastrichtian) in Alabama and Mississippi strongly suggests that the Late Cretaceous sea floor was within the photic zone. The maximum depth of deposition is calculated from an equation based on eye morphology and efficiency and estimates of the vertical light attenuation. In this equation, K, the vertical light attenuation coefficient, is the most critical variable because it is the divisor for the rest of the equation. Rates of accumulation of coccoliths during the Cretaceous are estimated and are on the same order as those in modern areas of high phytoplankton production, suggesting similar pigment and coccolith concentrations in the water column. Values of K are known for a wide range of water masses and pigment concentrations, including areas of high phytoplankton production; thus light attenuation through the Cretaceous seas can be estimated reliably. Waters in which attenuation is due only to biogenic matter-conditions that result in deposition of relatively pure chalk-have values of K ranging between 0.2 and 0.3. Waters rich in phytoplankton and mud-conditions that result in deposition of marl-have K values as great as 0.5. Substituting these values for K results in depth range of 65 to 90 m for deposition of chalk and depth of 35 m for deposition of marl. These depth values suggest that deposition of many Cretaceous chalks and marls around the world were deposited under relatively shallow conditions.

  1. Hemipelagic cephalopods from the Maastrichtian (late Cretaceous) Parras Basin at La Parra, Coahuila, Mexico, and their implications for the correlation of the lower Difunta Group

    NASA Astrophysics Data System (ADS)

    Ifrim, Christina; Stinnesbeck, Wolfgang; Garza, Rufino Rodríguez; Ventura, José Flores

    2010-04-01

    Few biostratigraphic data exist from the Parras and La Popa basins, mainly due to the absence of index fossils. This paper describes 19 ammonoid species from 15 genera and 1 nautilid from La Parra, southeastern Coahuila, Mexico. The assemblage consists of Tethyan [( Baculites ovatus, Brahmaites ( Anabrahmaites) vishnu, Fresvillia constricta, Hauericeras rembda, Pachydiscus ( P.) ex gr. neubergicus, Solenoceras reesidei, Tetragonites cf. superstes], cosmopolitan ( Anagaudryceras politissimum, Desmophyllites diphylloides, Diplomoceras cylindraceum, Gaudryceras kayei, Phyllopachyceras forbesianum, Pseudophyllites indra), and cold water taxa [ Fresvillia teres, Hypophylloceras ( Neophylloceras) surya, H. ( N.) hetonaiense, Pachydiscus ( P.) cf. egertoni]. Eutrephoceras sp. and Menuites juv. sp. were not determined to species level. A similar assemblage was recently described from the coeval Méndez Formation at Cerralvo, Nuevo León. Species endemic to North America, particularly the Western Interior Seaway, are absent at La Parra. The ammonoid assemblage and associated planktonic foraminifers allow for precise biostratigraphic assignation to the early Maastrichtian planktonic foraminiferal zone CF 5, and thus provide an important marker level for correlation of the lower Difunta Group. The new biostratigraphic data presented herein allow for the first time precise dating of the Cañon del Tule Formation of the Difunta Group. Their combination with existing sequence- and magnetostratigraphic data improve the correlation of the lower Difunta Group with time-equivalent lithostratigraphic units such as the Cárdenas Formation in Mexico. They also provide new insight into ammonoid migration patterns induced by sea-level changes. Baculites ovatus migrated into the La Popa Basin as a result of the sea-level highstand documented at La Parra.

  2. Orbital dystopia due to orbital roof defect.

    PubMed

    Rha, Eun Young; Joo, Hong Sil; Byeon, Jun Hee

    2013-01-01

    We performed a retrospective review of patients who presented with delayed dystopia as a consequence of an orbital roof defect due to fractures and nontraumatic causes to search for a correlation between orbital roof defect size and surgical indications for the treatment thereof. Retrospective analyses were performed in 7 patients, all of whom presented with delayed dystopia due to orbital roof defects, between January 2001 and June 2011. The causes of orbital roof defects were displaced orbital roof fractures (5 cases), tumor (1 case), and congenital sphenoid dysplasia (1 case). All 7 patients had initially been treated conservatively and later presented with significant dystopia. The sizes of the defects were calculated on computed tomographic scans. Among the 7 patients, aspiration of cerebrospinal fluid, which caused ocular symptoms, in 1 patient with minimal displaced orbital roof and reconstruction with calvarial bone, titanium micromesh, or Medpor in 6 other patients were performed. The minimal size of the orbital roof in patients who underwent orbital roof reconstruction was 1.2 cm (defect height) x 1.0 cm (defect length), 0.94 cm(2). For all patients with orbital dystopia, displacement of the globe was corrected without any complications, regardless of whether the patient was evaluated grossly or by radiology. In this retrospective study, continuous monitoring of clinical signs and active surgical management should be considered for cases in which an orbital roof defect is detected, even if no definite symptoms are noted, to prevent delayed sequelae.

  3. Sclerosing idiopathic orbital inflammation.

    PubMed

    Brannan, Paul A; Kersten, Robert C; Kulwin, Dwight R

    2006-01-01

    A 5-year-old girl referred for orbital cellulitis was found to have a right orbital mass. Computed tomography revealed a mass occupying the inferotemporal orbit, extending into the maxillary sinus. Biopsy yielded a diagnosis of sclerosing idiopathic orbital inflammation. She was successfully treated with prednisone.

  4. The Campanian-Maastrichtian foraminiferal biostratigraphy of the basement sediments from the southern Pannonian Basin (Vojvodina, northern Serbia): implications for the continuation of the Eastern Vardar and Sava zones

    NASA Astrophysics Data System (ADS)

    Dunčić, Milena; Dulić, Ivan; Popov, Olivera; Bogićević, Goran; Vranjković, Alan

    2017-04-01

    Micropalaeontological and biostratigraphical studies included Campanian-Maastrichtian complexes from five oil exploration wells drilled in northern Serbia (Vojvodina): the first is a carbonate-clastic complex and second is a complex containing ophiolites intercalated with hemipelagic and pelagic sediments. Within the studied complexes, rich associations of planktonic and benthic foraminifera, calcareous nannoplankton, palynomorphs, as well as shallow and deep-water fossil detritus were determined. The presence of relatively rich associations of planktonic foraminifera allowed recognition of two biozones: the Globotruncana ventricosa Zone, observed in the sediments of the carbonate-clastic complex and the Gansserina gansseri Zone, observed in both complexes. Except biozones, based on documented index species, for some units in both complexes, larger benthic foraminifera species had special biostratigraphical value, and in some of them, the calcareous nannoplankton zones were recognized. The studied complexes represent deep-water formations, generated in oceanic island arc and trough zones. The presence of limestones, which originate from destroyed rudist reefs, is explained by transfer by means of gravitational transport mechanisms of shallow-water sediments to deep-water depositional environments. In this paper, the results of more detailed biostratigraphical and palaeo-ecological studies of foraminifera associations in Campanian-Maastrichtian complexes in Vojvodina are presented. Combined with lithological studies, seven units were determined within the complexes. The obtained results are important as a part of multidisciplinary, regional exploration of both complexes, generated in specific geological conditions, that today constitute a part of the pre-Neogene basement complex in the southeastern part of the Pannonian Basin. The Campanian- Maastrichtian carbonate-clastic complex represents sedimentary cover of the Eastern Vardar Ophiolitic Unit, while the

  5. Orbital fractures: a review

    PubMed Central

    Joseph, Jeffrey M; Glavas, Ioannis P

    2011-01-01

    This review of orbital fractures has three goals: 1) to understand the clinically relevant orbital anatomy with regard to periorbital trauma and orbital fractures, 2) to explain how to assess and examine a patient after periorbital trauma, and 3) to understand the medical and surgical management of orbital fractures. The article aims to summarize the evaluation and management of commonly encountered orbital fractures from the ophthalmologic perspective and to provide an overview for all practicing ophthalmologists and ophthalmologists in training. PMID:21339801

  6. Transfer orbit determination accuracy for orbit maneuvers

    NASA Astrophysics Data System (ADS)

    Pinheiro, Mery Passos

    This work intends to show the accuracy of the orbital elements determined during transfer orbit as a function of data span, as well as the feasibility of performance maneuvers. The orbit estimator used is a weighted least squares algorithm. The observation vector is composed of angle data (azimuth and elevation) and range data and are from the Astra IC mission. The state vector is either propagated by Brower model or numerical integration (for small eccentricities and inclination). The complete software to determine the orbit has been developed by Hughes Aircraft and been used for all Hughes satellite mission.

  7. Lunar Reconnaissance Orbiter Orbit Determination Accuracy Analysis

    NASA Technical Reports Server (NTRS)

    Slojkowski, Steven E.

    2014-01-01

    Results from operational OD produced by the NASA Goddard Flight Dynamics Facility for the LRO nominal and extended mission are presented. During the LRO nominal mission, when LRO flew in a low circular orbit, orbit determination requirements were met nearly 100% of the time. When the extended mission began, LRO returned to a more elliptical frozen orbit where gravity and other modeling errors caused numerous violations of mission accuracy requirements. Prediction accuracy is particularly challenged during periods when LRO is in full-Sun. A series of improvements to LRO orbit determination are presented, including implementation of new lunar gravity models, improved spacecraft solar radiation pressure modeling using a dynamic multi-plate area model, a shorter orbit determination arc length, and a constrained plane method for estimation. The analysis presented in this paper shows that updated lunar gravity models improved accuracy in the frozen orbit, and a multiplate dynamic area model improves prediction accuracy during full-Sun orbit periods. Implementation of a 36-hour tracking data arc and plane constraints during edge-on orbit geometry also provide benefits. A comparison of the operational solutions to precision orbit determination solutions shows agreement on a 100- to 250-meter level in definitive accuracy.

  8. Orbits: Computer simulation

    NASA Technical Reports Server (NTRS)

    Muszynska, A.

    1985-01-01

    In rotating machinery dynamics an orbit (Lissajous curve) represents the dynamic path of the shaft centerline motion during shaft rotation and resulting precession. The orbit can be observed with an oscilloscope connected to XY promixity probes. The orbits can also be simulated by a computer. The software for HP computer simulates orbits for two cases: (1) Symmetric orbit with four frequency components with different radial amplitudes and relative phase angles; and (2) Nonsymmetric orbit with two frequency components with two different vertical/horizontal amplitudes and two different relative phase angles. Each orbit carries a Keyphasor mark (one-per-turn reference). The frequencies, amplitudes, and phase angles, as well as number of time steps for orbit computation, have to be chosen and introduced to the computer by the user. The orbit graphs can be observed on the computer screen.

  9. Manned Venus Orbiting Mission

    NASA Technical Reports Server (NTRS)

    Willis, E. A., Jr.

    1967-01-01

    Manned orbiting stopover round trips to Venus are studied for departure dates between 1975 and 1986 over a range of trip times and stay times. The use of highly elliptic parking orbits at Venus leads to low initial weights in Earth orbit compared with circular orbits. For the elliptic parking orbit, the effect of constraints on the low altitude observation time on the initial weight is shown. The mission can be accomplished with the Apollo level of chemical propulsion, but advanced chemical or nuclear propulsion can give large weight reductions. The Venus orbiting mission weights than the corresponding Mars mission.

  10. Primary orbital melanoma associated with orbital melanocytosis.

    PubMed

    Rice, C D; Brown, H H

    1990-08-01

    We report a case of primary orbital melanoma in a 17-year-old girl. The patient presented with painless proptosis during the first trimester of pregnancy. Computed tomography demonstrated a well-circumscribed mass located infra-temporally in the right orbit. The tumor was bluish-black, grossly encapsulated, and associated with orbital blue nevi. Histologic examination of the mass revealed a pigmented spindle-cell neoplasm. On electron microscopy, the presence of premelanosomes and the absence of basal lamina supported the diagnosis of melanoma. Malignant transformation of a preexisting nevus is postulated since perineural foci of benign dendritic melanocytes were seen within the melanoma. There has been no recurrence or metastasis in a 2-year follow-up. Of 30 primary orbital melanomas reviewed, 12 (40%) were associated with periorbital pigmentary disorders, such as oculodermal melanocytosis, blue nevus, and ocular melanocytosis. Our case is unique since the pigmentary lesions were limited to the orbital tissues.

  11. Did tropical rainforest vegetation exist during the Late Cretaceous? New data from the late Campanian to early Maastrichtian Olmos Formation, Coahuila, Mexico.

    NASA Astrophysics Data System (ADS)

    Upchurch, G. R.; Estrada-Ruiz, E.; Cevallos-Ferriz, S. S.

    2008-12-01

    A major problem in paleobotany and paleoclimatology is the origin of modern tropical and paratropical rainforests. Studies of leaf macrofossils, beginning with those of Wolfe and Upchurch, have suggested that tropical and paratropical (i.e., megathermal) rainforests with dominant angiosperms are of Cenozoic origin, and that comparable vegetation was either absent or greatly restricted during the Late Cretaceous. Earth System modeling studies, in contrast, predict the existence of megathermal rainforest vegetation during the mid- and Late Cretaceous, though with less areal extent than during the Late Cenozoic and Recent. Megathermal climate with year-round precipitation is simulated along the paleoequator and along the northern margin of the Tethys Ocean, and tends to occur in highly focused regions, in contrast to the more latitudinally zoned pattern of the Recent. Low-resolution climatic indicators, such as the distribution of coals and tree fern spores, are consistent with evidence from climate modeling for megathermal wet climates during the Late Cretaceous, and by extension megathermal rainforest vegetation. However, corroborative data from plant macrofossil assemblages is needed, because the physiognomy of leaves and woods directly reflects plant adaptation to the environment and can estimate climate independently of the generic and familial affinities of the paleoflora. Newly collected plant macrofossil assemblages from the late Campian to early Maastrichtian Olmos Formation of Coahuila, Mexico, provide evidence for megathermal rainforest vegetation on the northern margin of the Tethys Ocean at approximately 35 degrees paleolatitude. The newly collected leaf flora is 72 percent entire- margined and has abundant palms, features typical of modern megathermal rainforests. Thirty percent of the species have large leaves, and 50 percent of the species have drip tips, features indicative of wet conditions. Simple and multiple regression functions based on the

  12. Stable isotope (C and N) and sedimentary facies analyses of the Cantwell Formation, Denali National Park, Alaska as indicators of Maastrichtian paleoenvironment

    NASA Astrophysics Data System (ADS)

    Salazar Jaramillo, S.; Fowell, S. J.; Wooller, M. J.; Mccarthy, P. J.; Benowitz, J.

    2012-12-01

    Sedimentary facies and stable isotope analyses of Lower Cantwell Formation outcrops on the East Fork of the Toklat River in Denali National Park, Alaska, reveal a correlation between positive δ13C excursions and carbonaceous facies. 238U/206Pb zircon dating of a bentonite layer from our measured sections yields a crystallization age of 69.5 ± 0.69 Ma, indicating that dinosaur tracks identified in this part of the Cantwell Formation are of early Maastrichtian age. This date establishes the coeval nature of dinosaur bones from the Prince Creek Formation on Alaska's North Slope, allows reconstruction of Late Cretaceous climate gradients, and brackets the age of the Lower Cantwell-Upper Cantwell unconformity (~69 Ma to ~60 Ma) linked to the final docking of the Wrangell Composite Terrane. The Late Cretaceous Cantwell Formation is composed of nonmarine sandstone, siltstone, shale, carbonaceous mudstone and, locally, weakly developed paleosols. Facies associations are interpreted as levees, crevasse channels, crevasse splays, and floodplains, which were part of an anastomosed river system. δ13C, δ15N, C/N and TOC values of bulk organic matter were measured in order to reconstruct the local paleoenvironment and facilitate chemostratigraphic correlation with dinosaur-bearing strata on Alaska's North Slope. C/N ratios fall between 5 and 33, indicating that the organic matter is likely comprised of terrestrial plants and lacustrine algae. Throughout the 123 m section, δ13C values of bulk organic matter from sandstone, siltstone, and shale range between -27.1 and -24.9‰. Wood fragments and bulk organic samples from carbonaceous mudstone have higher TOC values and more positive δ13C values, ranging from -24.1 to -22.4‰. Positive δ13C excursions could reflect one or a combination of: 1) changes in composition of the vegetation (e.g., conifers vs. more mixed organic matter); 2) changes in sources of organic material (lacustrine vs. terrestrial); 3) changes in past

  13. Paleoenvironments, organic petrology and Rock-Eval studies on source rock facies of the Lower Maastrichtian Patti Formation, southern Bida Basin, Nigeria

    NASA Astrophysics Data System (ADS)

    Akande, S. O.; Ojo, O. J.; Erdtmann, B. D.; Hetenyi, M.

    2005-06-01

    The southern Bida Basin in central Nigeria forms a part of the larger Bida or Middle Niger Basin, which is contiguous with the south east trending (petroliferous) Anambra Basin. These basins were major depocenters for Campanian-Maastrichtian sediments in southern and central Nigeria prior to the build up of the Tertiary Niger delta. The successions in the southern Bida Basin consist of the basal Lokoja Formation, overlain by the Patti Formation and capped by the Agbaja Formation. The Lokoja Formation is a sequence of matrix supported conglomerates and sandstones overlying the Pre-Cambrian to Lower Paleozoic basement. Depositional environments are predominantly within fluvial systems of a continental setting. The Patti Formation consists of dark grey carbonaceous shales; mudstone and siltstones representing flood plains to shallow marine deposits with likely organic rich intervals. The overlying Agbaja Formation is made up of ferruginised oolitic and kaolinitic mudstone of a marginal marine environment. Twenty samples of shales of the Patti Formation were studied by incident light microscopy and geochemical analysis to determine the maceral components, geochemical type and potential yield of the pyrolysate. Maceral analysis indicate a large abundance of vitrinite (50-85%; mean = 66%); moderate abundance of liptinites (10-33%; mean = 18%) and lesser amounts of inertinite (9-40%; mean = 16%). Total organic carbon (TOC) values vary from 0.17 to 3.8 wt.% (mean = 2.1 wt.%) with most samples having greater than 2 wt.% TOC. Three of the samples yield greater than 2 kg (HC)/ton of rock suggesting a fair source rock potential. Most of the samples are thermally immature to marginally mature with vitrinite reflectance ranging from 0.4 to 0.6% Rom and Tmax values of 407-426 °C. Given the prevalence of the humic Type III kerogen, maturity and hydrocarbon potential yields, we conclude that the Patti Formation source rock facies have moderate to fair potential for gaseous

  14. Lunar orbiting prospector

    NASA Technical Reports Server (NTRS)

    1988-01-01

    One of the prime reasons for establishing a manned lunar presence is the possibility of using the potential lunar resources. The Lunar Orbital Prospector (LOP) is a lunar orbiting platform whose mission is to prospect and explore the Moon from orbit in support of early lunar colonization and exploitation efforts. The LOP mission is divided into three primary phases: transport from Earth to low lunar orbit (LLO), operation in lunar orbit, and platform servicing in lunar orbit. The platform alters its orbit to obtain the desired surface viewing, and the orbit can be changed periodically as needed. After completion of the inital remote sensing mission, more ambitious and/or complicated prospecting and exploration missions can be contemplated. A refueled propulsion module, updated instruments, or additional remote sensing packages can be flown up from the lunar base to the platform.

  15. Five Equivalent d Orbitals

    ERIC Educational Resources Information Center

    Pauling, Linus; McClure, Vance

    1970-01-01

    Amplifies and clarifies a previous paper on pyramidal d orbitals. Discusses two sets of pyramid d orbitals with respect to their maximum bond strength and their symmetry. Authors described the oblate and prolate pentagonal antiprisms arising from the two sets of five equivalent d orbitals. (RR)

  16. Introducing Earth's Orbital Eccentricity

    ERIC Educational Resources Information Center

    Oostra, Benjamin

    2015-01-01

    Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

  17. Introducing Earth's Orbital Eccentricity

    ERIC Educational Resources Information Center

    Oostra, Benjamin

    2015-01-01

    Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

  18. SEASAT B orbit synthesis

    NASA Technical Reports Server (NTRS)

    Rea, F. G.; Warmke, J. M.

    1976-01-01

    Addition were made to Battelle's Interactive Graphics Orbit Selection (IGOS) program; IGOS was exercised via telephone lines from JPL, and candidate SEASAT orbits were analyzed by Battelle. The additions to the program enable clear understanding of the implications of a specific orbit to the diverse desires of the SEASAT user community.

  19. Lunar Reconnaissance Orbiter Orbit Determination Accuracy Analysis

    NASA Technical Reports Server (NTRS)

    Slojkowski, Steven E.

    2014-01-01

    LRO definitive and predictive accuracy requirements were easily met in the nominal mission orbit, using the LP150Q lunar gravity model. center dot Accuracy of the LP150Q model is poorer in the extended mission elliptical orbit. center dot Later lunar gravity models, in particular GSFC-GRAIL-270, improve OD accuracy in the extended mission. center dot Implementation of a constrained plane when the orbit is within 45 degrees of the Earth-Moon line improves cross-track accuracy. center dot Prediction accuracy is still challenged during full-Sun periods due to coarse spacecraft area modeling - Implementation of a multi-plate area model with definitive attitude input can eliminate prediction violations. - The FDF is evaluating using analytic and predicted attitude modeling to improve full-Sun prediction accuracy. center dot Comparison of FDF ephemeris file to high-precision ephemeris files provides gross confirmation that overlap compares properly assess orbit accuracy.

  20. Orbital Plasmacytoma Mimicking an Orbital Abscess.

    PubMed

    Russell, David J; Seiff, Stuart R

    An 83-year-old male with a 15-month history of multiple myeloma presented with acute onset of swelling, redness, and pain around his right eye. CT scan was consistent with an orbital abscess. The patient was taken to the operating room for drainage of the orbital abscess. Abnormal tissue was encountered intraoperatively so biopsies were taken. His cultures grew only one colony of coagulase-negative Staphylococcus aureus. The histopathology from the biopsies showed a CD-138 positive plasma cell neoplasia consistent with a plasmacytoma. Plasmacytomas have been reported to present as orbital cellulitis and as abscesses in other locations in the body, but to our knowledge, this is the first case of a plasmacytoma presenting as an orbital abscess.

  1. Orbit Software Suite

    NASA Technical Reports Server (NTRS)

    Osgood, Cathy; Williams, Kevin; Gentry, Philip; Brownfield, Dana; Hallstrom, John; Stuit, Tim

    2012-01-01

    Orbit Software Suite is used to support a variety of NASA/DM (Dependable Multiprocessor) mission planning and analysis activities on the IPS (Intrusion Prevention System) platform. The suite of Orbit software tools (Orbit Design and Orbit Dynamics) resides on IPS/Linux workstations, and is used to perform mission design and analysis tasks corresponding to trajectory/ launch window, rendezvous, and proximity operations flight segments. A list of tools in Orbit Software Suite represents tool versions established during/after the Equipment Rehost-3 Project.

  2. Painless orbital myositis.

    PubMed

    Chakor, Rahul T; Santhosh, N S

    2012-07-01

    Idiopathic orbital inflammation is the third most common orbital disease, following Graves orbitopathy and lymphoproliferative diseases. We present a 11 year old girl with 15 days history of painless diplopia. There was no history of fluctuation of symptoms, drooping of eye lids or diminished vision. She had near total restricted extra-ocular movements and mild proptosis of the right eye. There was no conjunctival injection, chemosis, or bulb pain. There was no eyelid retraction or lid lag. Rest of the neurological examination was unremarkable.Erythrocyte sedimentation rate was raised with eosinophilia. Antinuclear antibodies were positive. Liver, renal and thyroid functions were normal. Antithyroid, double stranded deoxyribonucleic acid and acetylcholine receptor antibodies were negative. Repetitive nerve stimulation was negative. Magnetic resonance imaging (MRI) of the orbit was typical of orbital myositis. The patient responded to oral steroids. Orbital myositis can present as painless diplopia. MRI of orbit is diagnostic in orbital myositis.

  3. Solar Sail Optimal Orbit Transfers to Synchronous Orbits

    NASA Technical Reports Server (NTRS)

    Powers, Robert B.; Coverstone, Victoria; Prussing, John E.; Lunney, Bryan C. (Technical Monitor)

    1999-01-01

    A constant outward radial thrust acceleration can be used to reduce the radius of a circular orbit of specified period. Heliocentric circular orbits are designed to match the orbital period of Earth or Mars for various radial thrust accelerations and are defined as synchronous orbits. Minimum-time solar sail orbit transfers to these synchronous heliocentric orbits are presented.

  4. Orbit Determination of the Lunar Reconnaissance Orbiter

    NASA Technical Reports Server (NTRS)

    Mazarico, Erwan; Rowlands, D. D.; Neumann, G. A.; Smith, D. E.; Torrence, M. H.; Lemoine, F. G.; Zuber, M. T.

    2011-01-01

    We present the results on precision orbit determination from the radio science investigation of the Lunar Reconnaissance Orbiter (LRO) spacecraft. We describe the data, modeling and methods used to achieve position knowledge several times better than the required 50-100m (in total position), over the period from 13 July 2009 to 31 January 2011. In addition to the near-continuous radiometric tracking data, we include altimetric data from the Lunar Orbiter Laser Altimeter (LOLA) in the form of crossover measurements, and show that they strongly improve the accuracy of the orbit reconstruction (total position overlap differences decrease from approx.70m to approx.23 m). To refine the spacecraft trajectory further, we develop a lunar gravity field by combining the newly acquired LRO data with the historical data. The reprocessing of the spacecraft trajectory with that model shows significantly increased accuracy (approx.20m with only the radiometric data, and approx.14m with the addition of the altimetric crossovers). LOLA topographic maps and calibration data from the Lunar Reconnaissance Orbiter Camera were used to supplement the results of the overlap analysis and demonstrate the trajectory accuracy.

  5. Telescope in lunar orbit

    NASA Technical Reports Server (NTRS)

    Page, T.

    1985-01-01

    The use of a large telescope in high lunar orbit 4000 km above the Moon's equator is proposed. It is recognized that the Hubble Space Telescope (ST), will provide the necessary capabilities if it can be transferred to lunar orbit. The Orbital Transfer Vehicle (OTV), will be able to scan the lunar surface, locate small outcrops of minerals important to base development, support early base operations and undertake detailed geophysical exploration of the whole lunar surface.

  6. Saturn orbiter mission study

    NASA Technical Reports Server (NTRS)

    Wells, W. C.; Sullivan, R. J.

    1973-01-01

    A preliminary analysis of the important aspects of missions orbiting the planet Saturn is provided. Orbital missions to Saturn is given serious consideration for the 1980's, or after flybys by Pioneer 10/G and Mariner Jupiter-Saturn 1977. An attempt is made to characterize Saturn orbiters in detail so that comparisons with Jupiter missions can be made. The scientific objectives of Saturn exploration are grouped under four topics: (1) the atmosphere, (2) the magnetosphere, (3) the rings, and (4) the satellites.

  7. Orbital angioleiomyoma: A rare orbital neoplasm.

    PubMed

    Alam, Md Shahid; Subramanian, Nirmala; Koka, Kirthi; Subramanian, Krishnakumar

    2016-01-01

    A 44-year-old male patient presented with painless progressive proptosis of left eye for the last 20 years. Examination revealed a purplish vascular mass extending from the medial orbital region to the surface of the globe. He underwent complete excision of the mass via an anterior orbitotomy approach. Histopathology and immunohistochemistry revealed a diagnosis of angioleiomyoma. No recurrence was noted at 1 year of follow-up. Angioleiomyomas are benign smooth muscle tumors with an additional vascular component. Their occurrence in the orbit is extremely rare with only three cases reported in literature till date. We report a fourth case of angioleiomyoma of the orbit with the longest duration of presentation of 20 years.

  8. Magnetospheric Multiscale (MMS) Orbit

    NASA Image and Video Library

    This animation shows the orbits of Magnetospheric Multiscale (MMS) mission, a Solar-Terrestrial Probe mission comprising of four identically instrumented spacecraft that will study the Earth's magn...

  9. Orbital Debris: A Chronology

    NASA Technical Reports Server (NTRS)

    Portree, Davis S. F. (Editor); Loftus, Joseph P., Jr. (Editor)

    1999-01-01

    This chronology covers the 37-year history of orbital debris concerns. It tracks orbital debris hazard creation, research, observation, experimentation, management, mitigation, protection, and policy. Included are debris-producing, events; U.N. orbital debris treaties, Space Shuttle and space station orbital debris issues; ASAT tests; milestones in theory and modeling; uncontrolled reentries; detection system development; shielding development; geosynchronous debris issues, including reboost policies: returned surfaces studies, seminar papers reports, conferences, and studies; the increasing effect of space activities on astronomy; and growing international awareness of the near-Earth environment.

  10. Family of Orbiters

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image shows the paths of three spacecraft currently in orbit around Mars, as well as the path by which NASA's Phoenix Mars Lander will approach and land on the planet. The t-shaped crosses show where the orbiters will be when Phoenix enters the atmosphere, while the x-shaped crosses show their location at landing time.

    All three orbiters, NASA's Mars Reconnaissance Orbiter, NASA's Mars Odyssey and the European Space Agency's Mars Express, will be monitoring Phoenix during the final steps of its journey to the Red Planet.

    Phoenix will land just south of Mars's north polar ice cap.

  11. Introducing Earth's Orbital Eccentricity

    NASA Astrophysics Data System (ADS)

    Oostra, Benjamin

    2015-12-01

    Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is small, and its only effect on the seasons is their unequal durations. Here I show a pleasant way to guide students to the actual value of Earth's orbital eccentricity, starting from the durations of the four seasons. The date of perihelion is also found.

  12. Early diagenetic stabilization of trace elements in reptile bone remains as an indicator of Maastrichtian Late Paleocene climatic changes: evidence from the Naran Bulak locality, the Gobi Desert (South Mongolia)

    NASA Astrophysics Data System (ADS)

    Samoilov, V. S.; Benjamini, Ch.; Smirnova, E. V.

    2001-08-01

    Maastrichtian dinosaur bone remains from the Naran Bulak locality (the Gobi Desert) with well-preserved bone textural features are enriched in some trace elements, primarily in REE. These features of vertebrate fossils were formed during diagenesis following rapid burial in mudflow sediments, and prior to postfossilization epigenetic changes. Trace elements are mainly concentrated in diagenetic apatite. Their contents in the bones correlate with that in their enclosing sediments for both maxima and minima. Fossil and sediment compositions were established under the influence of paleoclimate. They are correlated with long-term climatic changes with the aridity maximum at the K/T boundary. Climatic changes were recorded via the change of salinity of waters interacting with the buried vertebrate remains.

  13. Revised Stratigraphy of The Nallıhan-Dudaş (Beypazarı) Area and Significance of the Campanian-Maastrichtian Reef Occurrences Based on the Foraminiferal and Rudist Data

    NASA Astrophysics Data System (ADS)

    Görmüş, Muhittin; Sami Us, Muhammed; Özer, Sacit; Tekin, Erdoǧan; Akpınar, Serap; Kabakcı, Büşra

    2016-04-01

    Transgressive to regressive succession of the Cretaceous Period and Cretaceous Paleogene boundary from the Nallıhan-Beypazarı area have significant data to interpret the past geological history of northwestern Turkey. In the literature, main scientific differences are seen on the formation/lithodem names, their ages, contact relations and environmental interpretations. In the study, a revision has been made for a proper stratigraphy of the area. For the revised stratigraphy, the obtained results from our field and laboratory works and the literature information were used. The following stratigraphy were established from basement to top: the Permo-Triassic aged Sekli metamorphics, Jurassic to lower Cretaceous Soǧukçam formation, Campanian to Maastrichtian aged Dereköy Group-Haremiköy conglomerates, Çeǧiköy reefs, Nardin formation (Seben formation), Taraklı formation; the Paleogene aged Kızılçay group including Kızılbayır formation, Karaköy volcanoclastics, Selvipınar limestone, the Miocene-Pliocene terrestrial sediments, Çoraklar formation, Hırka formation, Akpınar formation, Çayırhan formation, Teke volkanics, Bozbelen formation, Kirmir formation. The main unconformities are between Jura and Campanian, Maastrichtian and Paleogene, Eocene and Miocene times. Among the geological units, the Çeǧiköy reefs having rich rudist fauna overlie the Haremiköy conglomerates in both sides at the north-Yeşilyurt village and at the south-Gökçeöz village. Another outcrop, Emincik is between two mentioned villages. Biohermal reefs mainly includes very rich rudists up to 40 centimetres in size around the Yeşilköy such as: Pironaea polystyla, Vaccinites loftusi, Hippurites sublaevis. Larger foraminifera Orbitoides medius, O. apiculatus, Siderolites calcitrapoides, Pseodosiderolites vidali are also common in the fore reef areas. Around the Gökçeöz at the south part, the identified rudists are as follows: Vaccinites sp., Hippurites aff. sublaevis

  14. Orbital granulocytic sarcoma

    PubMed Central

    Stockl, F.; Dolmetsch, A.; Saornil, M; Font, R.; Burnier, M.

    1997-01-01

    AIM—Orbital granulocytic sarcoma is a localised tumour composed of cells of myeloid origin. Histological diagnosis can be difficult in patients with poorly differentiated orbital tumours and no evidence of systemic leukaemia. The naphthol AS-D chloracetate esterase (Leder stain) and immunohistochemical stains for lysozyme and MAC387 were used to determine the staining characteristics of these tumours. A case series of seven patients with orbital granulocytic sarcoma is presented.
METHODS—Seven patients with orbital granulocytic sarcoma were studied. Haematoxylin and eosin, Leder, and lysozyme stained sections were available in seven cases. Unstained formalin fixed paraffin embedded sections of seven cases were available for immunohistochemical evaluation using the avidin-biotin-complex technique for MAC387.
RESULTS—The mean age of presentation of the orbital tumour was 8.8 years. Four patients presented with an orbital tumour before any systemic manifestations of leukaemia. In two cases the diagnosis of the orbital tumour and systemic leukaemia was made simultaneously. There was one case of established systemic myeloid leukaemia in remission with the subsequent development of orbital granulocytic sarcoma. Six of seven cases (86%) were positive for the Leder stain. Five of seven cases (71%) showed positive immunoreactivity with lysozyme. The immunohistochemical stain for MAC387 was positive in all seven cases (100%) including one case that was negative for both lysozyme and Leder stains.
CONCLUSIONS—Orbital granulocytic sarcoma is a tumour that affects children and can present with rapidly progressive proptosis. This tumour may develop before, during, or after the occurrence of systemic leukaemia. The combination of Leder and lysozyme stains is useful in the diagnosis of orbital granulocytic sarcoma. MAC387 may be a more reliable marker for orbital granulocytic sarcoma.

 PMID:9497470

  15. Congenital orbital encephalocele, orbital dystopia, and exophthalmos.

    PubMed

    Hwang, Kun; Kim, Han Joon

    2012-07-01

    We present here an exceedingly rare variant of a nonmidline basal encephalocele of the spheno-orbital type, and this was accompanied with orbital dystopia in a 56-year-old man. On examination, his left eye was located more inferolaterally than his right eye, and the patient said this had been this way since his birth. The protrusion of his left eye was aggravated when he is tired. His naked visual acuity was 0.7/0.3, and the ocular pressure was 14/12 mm Hg. The exophthalmometry was 10/14 to 16 mm. His eyeball motion was not restricted, yet diplopia was present in all directions. The distance from the midline to the medial canthus was 20/15 mm. The distance from the midline to the midpupillary line was 35/22 mm. The vertical dimension of the palpebral fissure was 12/9 mm. The height difference of the upper eyelid margin was 11 mm, and the height difference of the lower eyelid margin was 8 mm. Facial computed tomography and magnetic resonance imaging showed left sphenoid wing hypoplasia and herniation of the left anterior temporal pole and dura mater into the orbit, and this resulted into left exophthalmos and encephalomalacia in the left anterior temporal pole. To the best of our knowledge, our case is the second case of basal encephalocele and orbital dystopia.

  16. Statistical initial orbit determination

    SciTech Connect

    Taff, L.G.; Belkin, B.; Schweiter, G.A.; Sommar, K. D.H. Wagner Associates, Inc., Paoli, PA )

    1992-02-01

    For the ballistic missile initial orbit determination problem in particular, the concept of 'launch folders' is extended. This allows to decouple the observational data from the initial orbit determination problem per se. The observational data is only used to select among the possible orbital element sets in the group of folders. Monte Carlo simulations using up to 7200 orbital element sets are described. The results are compared to the true orbital element set and the one a good radar would have been able to produce if collocated with the optical sensor. The simplest version of the new method routinely outperforms the radar initial orbital element set by a factor of two in future miss distance. In addition, not only can a differentially corrected orbital element set be produced via this approach - after only two measurements of direction - but also an updated, meaningful, six-dimensional covariance array for it can be calculated. This technique represents a significant advance in initial orbit determination for this problem, and the concept can easily be extended to minor planets and artificial satellites. 9 refs.

  17. Orbiting Rainbows Simulation

    NASA Image and Video Library

    2015-04-22

    This simulated image shows how a cloud of glitter in geostationary orbit would be illuminated and controlled by two laser beams. As the cloud orbits Earth, grains scatter the sun's light at different angles like many tiny prisms, similar to how rainbows are produced from light being dispersed by water droplets. That is why the project concept is called "Orbiting Rainbows." The cloud functions like a reflective surface, allowing the exoplanet (displayed in the bottom right) to be imaged. The orbit path is shown in the top right. On the bottom left, Earth's image is seen behind the cloud. To image an exoplanet, the cloud would need to have a diameter of nearly 98 feet (30 meters). This simulation confines the cloud to a 3.3 x 3.3 x 3.3 foot volume (1 x 1 x 1 meter volume) to simplify the computations. The elements of the orbiting telescope are not to scale. Orbiting Rainbows is currently in Phase II development through the NASA Innovative Advanced Concepts (NIAC) Program. It was one of five technology proposals chosen for continued study in 2014. In the current phase, Orbiting Rainbows researchers are conducting small-scale ground experiments to demonstrate how granular materials can be manipulated using lasers and simulations of how the imaging system would behave in orbit. http://photojournal.jpl.nasa.gov/catalog/PIA19318

  18. Titan Orbiter Aerorover Mission

    NASA Technical Reports Server (NTRS)

    Sittler Jr., E. C.; Acuna, M.; Burchell, M. J.; Coates, A.; Farrell, W.; Flasar, M.; Goldstein, B. E.; Gorevan, S.; Hartle, R. E.; Johnson, W. T. K.

    2001-01-01

    We propose a combined Titan orbiter and Titan Aerorover mission with an emphasis on both in situ and remote sensing measurements of Titan's surface, atmosphere, ionosphere, and magnetospheric interaction. The biological aspect of the Titan environment will be emphasized by the mission (i.e., search for organic materials which may include simple organics to 'amono' analogues of amino acids and possibly more complex, lightening detection and infrared, ultraviolet, and charged particle interactions with Titan's surface and atmosphere). An international mission is assumed to control costs. NASA will provide the orbiter, launch vehicle, DSN coverage and operations, while international partners will provide the Aerorover and up to 30% of the cost for the scientific instruments through collaborative efforts. To further reduce costs we propose a single PI for orbiter science instruments and a single PI for Aerorover science instruments. This approach will provide single command/data and power interface between spacecraft and orbiter instruments that will have redundant central DPU and power converter for their instruments. A similar approach could be used for the Aerorover. The mission profile will be constructed to minimize conflicts between Aerorover science, orbiter radar science, orbiter radio science, orbiter imaging science, and orbiter fields and particles (FP) science. Additional information is contained in the original extended abstract.

  19. Reticulohistiocytoma of the Orbit

    PubMed Central

    Weissman, Heather M.; Hayek, Brent R.; Grossniklaus, Hans E.

    2015-01-01

    Reticulohistiocytoma is a rare, benign histiocytic proliferation of the skin or soft tissue. While ocular involvement has been documented in the past, there have been no previously reported cases of reticulohistiocytoma of the orbit. In this report, the authors describe a reticulohistiocytoma of the orbit in a middle-aged woman. PMID:24807799

  20. Analyzing Shuttle Orbiter Trajectories

    NASA Technical Reports Server (NTRS)

    Lear, W. M.

    1986-01-01

    LRBET4 program best-estimated-of-trajectory (BET) calculation for post-flight trajectory analysis of Shuttle orbiter. Produces estimated measurements for comparing predicted and actual trajectory of Earth-orbiting spacecraft. Kalman filter and smoothing filter applied to input data to estimate state vector, reduce noise, and produce BET. LRBET4 written in FORTRAN IV for batch execution.

  1. Stability of halo orbits.

    PubMed

    Howard, J E; Dullin, H R; Horányi, M

    2000-04-10

    We predict new populations of trapped nonequatorial ("halo") orbits of charged dust grains about an arbitrary axisymmetric planet. Simple equilibrium and stability conditions are derived, revealing dramatic differences between positively and negatively charged grains in prograde or retrograde orbits. Implications for the Cassini mission to Saturn are discussed.

  2. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Anna Michalak, an Orbiting Carbon Observatory science team member from the University of Michigan, Ann Arbor, speaks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  3. Orbital Shape Representations.

    ERIC Educational Resources Information Center

    Kikuchi, Osamu; Suzuki, Keizo

    1985-01-01

    Discusses the use of orbital shapes for instructional purposes, emphasizing that differences between polar, contour, and three-dimensional plots must be made clear to students or misconceptions will occur. Also presents three-dimensional contour surfaces for the seven 4f atomic orbitals of hydrogen and discusses their computer generation. (JN)

  4. Remote Controlled Orbiter Capability

    NASA Technical Reports Server (NTRS)

    Garske, Michael; delaTorre, Rafael

    2007-01-01

    The Remote Control Orbiter (RCO) capability allows a Space Shuttle Orbiter to perform an unmanned re-entry and landing. This low-cost capability employs existing and newly added functions to perform key activities typically performed by flight crews and controllers during manned re-entries. During an RCO landing attempt, these functions are triggered by automation resident in the on-board computers or uplinked commands from flight controllers on the ground. In order to properly route certain commands to the appropriate hardware, an In-Flight Maintenance (IFM) cable was developed. Currently, the RCO capability is reserved for the scenario where a safe return of the crew from orbit may not be possible. The flight crew would remain in orbit and await a rescue mission. After the crew is rescued, the RCO capability would be used on the unmanned Orbiter in an attempt to salvage this national asset.

  5. Mars Climate Orbiter

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The purpose of this mission is to study the climate history and the water distribution of Mars. Beautiful panoramic views of the shuttle on the launch pad, engine ignition, Rocket launch, and the separation and burnout of the Solid Rocket Boosters are shown. The footage also includes an animation of the mission. Detailed views of the path that the Orbiter traversed were shown. Once the Orbiter lands on the surface of Mars, it will dig a six to eight inch hole and collect samples from the planets' surface. The animation also included the prospective return of the Orbiter to Earth over the desert of Utah. The remote sensor on the Orbiter helps in finding the exact location of the Orbiter so that scientists may collect the sample and analyze it.

  6. Mars Climate Orbiter

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The purpose of this mission is to study the climate history and the water distribution of Mars. Beautiful panoramic views of the shuttle on the launch pad, engine ignition, Rocket launch, and the separation and burnout of the Solid Rocket Boosters are shown. The footage also includes an animation of the mission. Detailed views of the path that the Orbiter traversed were shown. Once the Orbiter lands on the surface of Mars, it will dig a six to eight inch hole and collect samples from the planets' surface. The animation also included the prospective return of the Orbiter to Earth over the desert of Utah. The remote sensor on the Orbiter helps in finding the exact location of the Orbiter so that scientists may collect the sample and analyze it.

  7. Orbital debris issues

    NASA Technical Reports Server (NTRS)

    Kessler, D. J.

    1985-01-01

    Man-made orbital debris, identified as a potential hazard to future space activities, is grouped into size categories. At least 79 satellites have broken up in orbit to date and, in combination with exploded rocket casings and antisatellite debris, threaten 10 km/sec collisions with other orbiting platforms. Only 5 percent of the debris is connected to payloads. The total population of orbiting objects over 4 cm in diameter could number as high as 15,000, and at 1 cm in diameter could be 32,000, based on NASA and NORAD studies. NASA has initiated the 10 yr Space Debris Assessment Program to characterize the hazards of orbiting debris, the potential damage to typical spacecraft components, and to identify means of controlling the damage.

  8. Congenital Orbital Teratoma.

    PubMed

    Pellerano, Fernando; Guillermo, Elvis; Garrido, Gloreley; Berges, Pedro

    2017-01-01

    We report a case of congenital orbital teratoma. A 3-day-old male, born at 39 weeks' gestation without relevant prenatal history, presented with a large vascularized proptotic mass distorting the left midface. Laboratory studies showed elevated serum alpha-fetoprotein (12,910 ng/ml). Computed tomography showed a multiloculated heterogeneous lesion composed of hypodense and hyperdense calcified areas encompassing the whole orbital cavity with expansion of the bony walls, as well as forward displacement and compression of the eyeball without extension to surrounding structures. Clinical, imaging and laboratory features were consistent with congenital orbital teratoma. Due to pronounced proptosis with exposure keratopathy and corneal perforation, no motility of the globe and no vision in the affected eye in a resource-limited setting, the patient underwent orbital exenteration. Histopathological examination confirmed the diagnosis of mature cystic teratoma. We describe the clinical course, radiographic and histopathological findings of this rare orbital tumor.

  9. Orbital Plots Using Gnuplot

    NASA Astrophysics Data System (ADS)

    Moore, Brian G.

    2000-06-01

    The plotting program Gnuplot is freely available, general purpose, easy to use, and available on a variety of platforms. Complex three-dimensional surfaces, including the familiar angular parts of the hydrogen atom orbitals, are easily represented using Gnuplot. Contour plots allow viewing the radial and angular variation of the probability density in an orbital. Examples are given of how Gnuplot is used in an undergraduate physical chemistry class to view familiar atomic orbitals in new ways or to generate views of orbital functions that the student may have not seen before. Gnuplot may also be easily integrated into the environment of a Web page; an example of this is discussed (and is available at http://onsager.bd.psu.edu/~moore/orbitals_gnuplot). The plotting commands are entered with a form and a CGI script is used to run Gnuplot and display the result back to the browser.

  10. Orbital Debris Mitigation

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.; Jarkey, D. R.; Stansbery, G.

    2014-01-01

    Policies on limiting orbital debris are found throughout the US Government, many foreign space agencies, and as adopted guidelines in the United Nations. The underlying purpose of these policies is to ensure the environment remains safe for the operation of robotic and human spacecraft in near- Earth orbit. For this reason, it is important to consider orbital debris mitigation during the design of all space vehicles. Documenting compliance with the debris mitigation guidelines occurs after the vehicle has already been designed and fabricated for many CubeSats, whereas larger satellites are evaluated throughout the design process. This paper will provide a brief explanation of the US Government Orbital Debris Mitigation Standard Practices, a discussion of international guidelines, as well as NASA's process for compliance evaluation. In addition, it will discuss the educational value of considering orbital debris mitigation requirements as a part of student built satellite design.

  11. Congenital Orbital Teratoma

    PubMed Central

    Pellerano, Fernando; Guillermo, Elvis; Garrido, Gloreley; Berges, Pedro

    2017-01-01

    We report a case of congenital orbital teratoma. A 3-day-old male, born at 39 weeks’ gestation without relevant prenatal history, presented with a large vascularized proptotic mass distorting the left midface. Laboratory studies showed elevated serum alpha-fetoprotein (12,910 ng/ml). Computed tomography showed a multiloculated heterogeneous lesion composed of hypodense and hyperdense calcified areas encompassing the whole orbital cavity with expansion of the bony walls, as well as forward displacement and compression of the eyeball without extension to surrounding structures. Clinical, imaging and laboratory features were consistent with congenital orbital teratoma. Due to pronounced proptosis with exposure keratopathy and corneal perforation, no motility of the globe and no vision in the affected eye in a resource-limited setting, the patient underwent orbital exenteration. Histopathological examination confirmed the diagnosis of mature cystic teratoma. We describe the clinical course, radiographic and histopathological findings of this rare orbital tumor. PMID:28275597

  12. Orbital endoscopic surgery.

    PubMed

    Prabhakaran, Venkatesh C; Selva, Dinesh

    2008-01-01

    Minimally invasive "keyhole" surgery performed using endoscopic visualization is increasing in popularity and is being used by almost all surgical subspecialties. Within ophthalmology, however, endoscopic surgery is not commonly performed and there is little literature on the use of the endoscope in orbital surgery. Transorbital use of the endoscope can greatly aid in visualizing orbital roof lesions and minimizing the need for bone removal. The endoscope is also useful during decompression procedures and as a teaching aid to train orbital surgeons. In this article, we review the history of endoscopic orbital surgery and provide an overview of the technique and describe situations where the endoscope can act as a useful adjunct to orbital surgery.

  13. Orbital Causes of Incomitant Strabismus

    PubMed Central

    Lueder, Gregg T.

    2015-01-01

    Strabismus may result from abnormal innervation, structure, or function of the extraocular muscles. Abnormalities of the orbital bones or masses within the orbit may also cause strabismus due to indirect effects on the extraocular muscles. This paper reviews some disorders of the orbit that are associated with strabismus, including craniofacial malformations, orbital masses, trauma, and anomalous orbital structures. PMID:26180465

  14. OL- ORBITAL LIFETIME PROGRAM

    NASA Technical Reports Server (NTRS)

    Orr, L. H.

    1994-01-01

    The Orbital Lifetime (OL) program analyzes the long-term motion of Earth-orbiting spacecraft at altitudes of up to 2500 kilometers. It models perturbations to the orbit caused by solar radiation pressure, atmospheric drag, and gravitational effects due to the sun, the moon, and Earth oblateness. OL can be used to predict the orbital lifetime and decay rate of a satellite. The atmospheric density models used in OL are the U.S. Standard Atmosphere for altitudes below 90 km and the Jacchia model for altitudes above 90 km. The Jacchia model requires solar flux and geomagnetic index for the date of orbit. An input file containing these values for 1984 to 1998 is supplied with the OL package. The solar radiation pressure calculations in OL will predict the amount of time a spacecraft is subjected to the Earth's shadow. Input to OL includes spacecraft physical characteristics, initial orbit parameters, and launch date/time. OL calculates time histories of the orbital elements, total lifetime, and decay rates. A spacecraft is considered 'down' at an altitude of 64 km. OL also generates a file of plot data which can be input to a user-supplied graphics program for lifetime plots of altitude against time. OL is written in FORTRAN 77 for interactive or batch execution and has been implemented on a DEC VAX series computer operating under VMS. This program was developed in 1985.

  15. Harmonically excited orbital variations

    SciTech Connect

    Morgan, T.

    1985-08-06

    Rephrasing the equations of motion for orbital maneuvers in terms of Lagrangian generalized coordinates instead of Newtonian rectangular cartesian coordinates can make certain harmonic terms in the orbital angular momentum vector more readily apparent. In this formulation the equations of motion adopt the form of a damped harmonic oscillator when torques are applied to the orbit in a variationally prescribed manner. The frequencies of the oscillator equation are in some ways unexpected but can nonetheless be exploited through resonant forcing functions to achieve large secular variations in the orbital elements. Two cases are discussed using a circular orbit as the control case: (1) large changes in orbital inclination achieved by harmonic excitation rather than one impulsive velocity change, and (2) periodic and secular changes to the longitude of the ascending node using both stable and unstable excitation strategies. The implications of these equations are also discussed for both artificial satellites and natural satellites. For the former, two utilitarian orbits are suggested, each exploiting a form of harmonic excitation. 5 refs.

  16. Orbital metastatic osteosarcoma.

    PubMed

    Rajabi, Mohammad Taher; Saeedi-Anari, Ghasem; Ramezani, Farshid; Tabatabaie, Seyed-Ziaeddin; Rajabi, Mohammad Bagher; Asadi Amoli, Fahimeh

    2015-02-01

    At an estimated incidence of 2 cases per million persons per year, osteosarcoma is the most common primary malignant bone tumor in children and adults, excluding hematopoietic intraosseous tumors. Orbital metastases of osteosarcoma are very rare. Only 5 cases of orbital metastasis of osteosarcoma previously reported in the literature. We report the case of a 19-year-old man with known history of osteosarcoma of right distal femur who presented with acute visual loss and progressive protrusion of his left eye. Orbital CT scan and MRI revealed orbital mass eroding orbital walls and intracranial invasion. He underwent superotemporal orbitotomy for debulking of orbital mass. Histopathological examination (HPE) of the specimen was reported as metastatic osteosarcoma with extensive tumor necrosis. Then he underwent adjuvant chemotherapy and palliative radiotherapy. Although orbital metastasis of osteosarcoma is a rare event, it seems it has had an increasing trend recently. so, making efforts to palliate the patient's symptoms by multidisciplinary teamwork and proper interaction among ophthalmologist, orthopedic surgeons and oncologists is necessary.

  17. Orbit Stabilization of Nanosat

    SciTech Connect

    JOHNSON,DAVID J.

    1999-12-01

    An algorithm is developed to control a pulsed {Delta}V thruster on a small satellite to allow it to fly in formation with a host satellite undergoing time dependent atmospheric drag deceleration. The algorithm uses four short thrusts per orbit to correct for differences in the average radii of the satellites due to differences in drag and one thrust to symmetrize the orbits. The radial difference between the orbits is the only input to the algorithm. The algorithm automatically stabilizes the orbits after ejection and includes provisions to allow azimuthal positional changes by modifying the drag compensation pulses. The algorithm gives radial and azimuthal deadbands of 50 cm and 3 m for a radial measurement accuracy of {+-} 5 cm and {+-} 60% period variation in the drag coefficient of the host. Approaches to further reduce the deadbands are described. The methodology of establishing a stable orbit after ejection is illustrated in an appendix. The results show the optimum ejection angle to minimize stabilization thrust is upward at 86{sup o} from the orbital velocity. At this angle the stabilization velocity that must be supplied by the thruster is half the ejection velocity. An ejection velocity of 0.02 m/sat 86{sup o} gives an azimuthal separation after ejection and orbit stabilization of 187 m. A description of liquid based gas thrusters suitable for the satellite control is included in an appendix.

  18. Discovery Orbiter Major Modifications

    NASA Image and Video Library

    2003-08-27

    During power-up of the orbiter Discovery in the Orbiter Processing Facility, a technician moves a circuit reset on the cockpit console. Discovery has been undergoing Orbiter Major Modifications in the past year, ranging from wiring, control panels and black boxes to gaseous and fluid systems tubing and components. These systems were deserviced, disassembled, inspected, modified, reassembled, checked out and reserviced, as were most other systems onboard. The work includes the installation of the Multifunction Electronic Display Subsystem (MEDS) - a state-of-the-art “glass cockpit.”

  19. Removal of orbital debris

    NASA Technical Reports Server (NTRS)

    Petro, Andrew J.; Talent, David L.

    1989-01-01

    The several methods presently identified for the reduction of orbital debris populations are broadly classifiable as either preventive or remedial, and fall within distinctive operational regimes. For all particles, (1) in the 250-2000-km altitude band, intelligent sweepers may be used; (2) for large objects, in the 80-250-km altitude band, orbital decay renders removal impractical; (3) for the 250-750-km altitude band, deorbit devices should be used; (4) for 750-2500-km altitude, OMV rendezvous for propulsive deorbit package attachment is foreseeable; and beyond 2500 km, (5) propulsive escape from earth orbit is required.

  20. Removal of orbital debris

    NASA Astrophysics Data System (ADS)

    Petro, Andrew J.; Talent, David L.

    The several methods presently identified for the reduction of orbital debris populations are broadly classifiable as either preventive or remedial, and fall within distinctive operational regimes. For all particles, (1) in the 250-2000-km altitude band, intelligent sweepers may be used; (2) for large objects, in the 80-250-km altitude band, orbital decay renders removal impractical; (3) for the 250-750-km altitude band, deorbit devices should be used; (4) for 750-2500-km altitude, OMV rendezvous for propulsive deorbit package attachment is foreseeable; and beyond 2500 km, (5) propulsive escape from earth orbit is required.

  1. Removal of orbital debris

    NASA Technical Reports Server (NTRS)

    Petro, Andrew J.; Talent, David L.

    1989-01-01

    The several methods presently identified for the reduction of orbital debris populations are broadly classifiable as either preventive or remedial, and fall within distinctive operational regimes. For all particles, (1) in the 250-2000-km altitude band, intelligent sweepers may be used; (2) for large objects, in the 80-250-km altitude band, orbital decay renders removal impractical; (3) for the 250-750-km altitude band, deorbit devices should be used; (4) for 750-2500-km altitude, OMV rendezvous for propulsive deorbit package attachment is foreseeable; and beyond 2500 km, (5) propulsive escape from earth orbit is required.

  2. Orbital-2 Mission

    NASA Image and Video Library

    2014-07-12

    The full Moon sets in the fog behind the Orbital Sciences Corporation Antares rocket, with the Cygnus spacecraft onboard, Saturday, July 12, 2014, launch Pad-0A, NASA's Wallops Flight Facility in Virginia. The Antares will launch with the Cygnus spacecraft filled with over 3,000 pounds of supplies for the International Space Station, including science experiments, experiment hardware, spare parts, and crew provisions. The Orbital-2 mission is Orbital Sciences' second contracted cargo delivery flight to the space station for NASA. Photo Credit: (NASA/Bill Ingalls)

  3. Orbital-2 Mission

    NASA Image and Video Library

    2014-07-12

    The Orbital Sciences Corporation Antares rocket, with the Cygnus spacecraft onboard, is seen during sunrise, Saturday, July 12, 2014, at launch Pad-0A of NASA's Wallops Flight Facility in Virginia. The Antares will launch with the Cygnus spacecraft filled with over 3,000 pounds of supplies for the International Space Station, including science experiments, experiment hardware, spare parts, and crew provisions. The Orbital-2 mission is Orbital Sciences' second contracted cargo delivery flight to the space station for NASA. Photo Credit: (NASA/Bill Ingalls)

  4. Orbital-2 Mission

    NASA Image and Video Library

    2014-07-11

    The Orbital Sciences Corporation Antares rocket, with the Cygnus spacecraft onboard, is seen on launch Pad-0A, Friday, July 11, 2014, at NASA's Wallops Flight Facility in Virginia. The Antares will launch with the Cygnus spacecraft filled with over 3,000 pounds of supplies for the International Space Station, including science experiments, experiment hardware, spare parts, and crew provisions. The Orbital-2 mission is Orbital Sciences' second contracted cargo delivery flight to the space station for NASA. Photo Credit: (NASA/Bill Ingalls)

  5. Orbit Determination Issues for Libration Point Orbits

    NASA Technical Reports Server (NTRS)

    Beckman, Mark; Bauer, Frank (Technical Monitor)

    2002-01-01

    Libration point mission designers require knowledge of orbital accuracy for a variety of analyses including station keeping control strategies, transfer trajectory design, and formation and constellation control. Past publications have detailed orbit determination (OD) results from individual libration point missions. This paper collects both published and unpublished results from four previous libration point missions (ISEE (International Sun-Earth Explorer) -3, SOHO (Solar and Heliospheric Observatory), ACE (Advanced Composition Explorer) and MAP (Microwave Anisotropy Probe)) supported by Goddard Space Flight Center's Guidance, Navigation & Control Center. The results of those missions are presented along with OD issues specific to each mission. All past missions have been limited to ground based tracking through NASA ground sites using standard range and Doppler measurement types. Advanced technology is enabling other OD options including onboard navigation using seaboard attitude sensors and the use of the Very Long Baseline Interferometry (VLBI) measurement Delta Differenced One-Way Range (DDOR). Both options potentially enable missions to reduce coherent dedicated tracking passes while maintaining orbital accuracy. With the increased projected loading of the DSN (Deep Space Network), missions must find alternatives to the standard OD scenario.

  6. Indian Mars Orbiter Mission

    NASA Astrophysics Data System (ADS)

    Bhardwaj, Anil

    The Mars Orbiter Mission (MOM) is the first interplanetary mission of India launched by Indian Polar Satellite Launch Vehicle (PSLV-XL) on 5 November 2013. It departed from Earth's orbit on Dec. 1, 2013, on its 300-days journey to Mars. MOM will reach Mars on Sept. 24, 2014. The orbit of MOM around Mars is highly elliptical with periapsis ~370 km and apoapsis ~80000 km, inclination 151 degree, and orbital period 3.15 sols. The spacecraft mass is 1350 kg, with dry mass of 500 kg and science payload mass of 14 kg. The spacecraft carries five science payloads, namely: Methane Sensor for Mars (MSM), Mars Colour Camera (MCC), Lyman Alpha Photometer (LAP), Mars Exospheric Neutral Composition Analyzer (MENCA), TIR Imaging Spectrometer (TIS). This paper will present the details of the instruments, observation plan, and expected science.

  7. MMS Orbit Animation

    NASA Image and Video Library

    This animation shows the orbits of Magnetospheric Multiscale (MMS)mission, a Solar Terrestrial Probes mission comprising of fouridentically instrumented spacecraft that will study the Earth’sm...

  8. Report on orbital debris

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The success of space endeavors depends upon a space environment sufficiently free of debris to enable the safe and dependable operation of spacecraft. An environment overly cluttered with debris would threaten the ability to utilize space for a wide variety of scientific, technological, military, and commercial purposes. Man made space debris (orbital debris) differs from natural meteoroids because it remains in earth orbit during its lifetime and is not transient through the space around the Earth. The orbital debris environment is considered. The space environment is described along with sources of orbital debris. The current national space policy is examined, along with ways to minimize debris generation and ways to survive the debris environment. International efforts, legal issues and commercial regulations are also examined.

  9. ARTEMIS Orbits Magnetic Moon

    NASA Image and Video Library

    NASA's THEMIS spacecraft have completed their mission and are still working perfectly, so NASA is re-directing the outermost two spacecraft to special orbits around the Moon. Now called ARTEMIS, th...

  10. Space Shuttle Orbiter ECLSS.

    NASA Technical Reports Server (NTRS)

    Stoll, O. T.; Laubach, G. E.; Gibb, J. W.

    1973-01-01

    The Orbiter Environmental Control and Life Support System (ECLSS) provides the functions of atmosphere revitalization, crew life support, active thermal conditioning, and airlock support for EVA and docking activities. The ECLSS must satisfy the requirements of orbital missions with four to ten crewmembers and mission duration of a few hours to 30 days and the requirements associated with an atmospheric horizontal flight test program and ferry flight missions. The ECLSS development plan utilizes an ECLSS ground test article and thermal/vacuum testing to support the first horizontal flight test at the end of 1976. The ground testing and horizontal flight test program certify the Orbiter ECLSS for the first orbital flight in early 1978.

  11. Orbiter entry aerothermodynamics

    NASA Technical Reports Server (NTRS)

    Ried, R. C.

    1985-01-01

    The challenge in the definition of the entry aerothermodynamic environment arising from the challenge of a reliable and reusable Orbiter is reviewed in light of the existing technology. Select problems pertinent to the orbiter development are discussed with reference to comprehensive treatments. These problems include boundary layer transition, leeward-side heating, shock/shock interaction scaling, tile gap heating, and nonequilibrium effects such as surface catalysis. Sample measurements obtained from test flights of the Orbiter are presented with comparison to preflight expectations. Numerical and wind tunnel simulations gave efficient information for defining the entry environment and an adequate level of preflight confidence. The high quality flight data provide an opportunity to refine the operational capability of the orbiter and serve as a benchmark both for the development of aerothermodynamic technology and for use in meeting future entry heating challenges.

  12. Space Shuttle Orbiter ECLSS.

    NASA Technical Reports Server (NTRS)

    Stoll, O. T.; Laubach, G. E.; Gibb, J. W.

    1973-01-01

    The Orbiter Environmental Control and Life Support System (ECLSS) provides the functions of atmosphere revitalization, crew life support, active thermal conditioning, and airlock support for EVA and docking activities. The ECLSS must satisfy the requirements of orbital missions with four to ten crewmembers and mission duration of a few hours to 30 days and the requirements associated with an atmospheric horizontal flight test program and ferry flight missions. The ECLSS development plan utilizes an ECLSS ground test article and thermal/vacuum testing to support the first horizontal flight test at the end of 1976. The ground testing and horizontal flight test program certify the Orbiter ECLSS for the first orbital flight in early 1978.

  13. Optical orbital debris spotter

    NASA Astrophysics Data System (ADS)

    Englert, Christoph R.; Bays, J. Timothy; Marr, Kenneth D.; Brown, Charles M.; Nicholas, Andrew C.; Finne, Theodore T.

    2014-11-01

    The number of man-made debris objects orbiting the Earth, or orbital debris, is alarmingly increasing, resulting in the increased probability of degradation, damage, or destruction of operating spacecraft. In part, small objects (<10 cm) in Low Earth Orbit (LEO) are of concern because they are abundant and difficult to track or even to detect on a routine basis. Due to the increasing debris population it is reasonable to assume that improved capabilities for on-orbit damage attribution, in addition to increased capabilities to detect and track small objects are needed. Here we present a sensor concept to detect small debris with sizes between approximately 1.0 and 0.01 cm in the vicinity of a host spacecraft for near real time damage attribution and characterization of dense debris fields and potentially to provide additional data to existing debris models.

  14. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Charles Miller talks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  15. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Panelists are seen during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  16. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Ralph Basilio talks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  17. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Eric Ianson speaks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  18. Tethered orbital refueling study

    NASA Technical Reports Server (NTRS)

    Fester, Dale A.; Rudolph, L. Kevin; Kiefel, Erlinda R.; Abbott, Peter W.; Grossrode, Pat

    1986-01-01

    One of the major applications of the space station will be to act as a refueling depot for cryogenic-fueled space-based orbital transfer vehicles (OTV), Earth-storable fueled orbit maneuvering vehicles, and refurbishable satellite spacecraft using hydrazine. One alternative for fuel storage at the space station is a tethered orbital refueling facility (TORF), separated from the space station by a sufficient distance to induce a gravity gradient force that settles the stored fuels. The technical feasibility was examined with the primary focus on the refueling of LO2/LH2 orbital transfer vehicles. Also examined was the tethered facility on the space station. It was compared to a zero-gravity facility. A tethered refueling facility should be considered as a viable alternative to a zero-gravity facility if the zero-gravity fluid transfer technology, such as the propellant management device and no vent fill, proves to be difficult to develop with the required performance.

  19. Habitability study shuttle orbiter

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Habitability design concepts for the Shuttle Orbiter Program are provided for MSC. A variety of creative solutions for the stated tasks are presented. Sketches, mock-ups, mechanicals and models are included for establishing a foundation for future development.

  20. Altimetry, Orbits and Tides

    NASA Technical Reports Server (NTRS)

    Colombo, O. L.

    1984-01-01

    The nature of the orbit error and its effect on the sea surface heights calculated with satellite altimetry are explained. The elementary concepts of celestial mechanics required to follow a general discussion of the problem are included. Consideration of errors in the orbits of satellites with precisely repeating ground tracks (SEASAT, TOPEX, ERS-1, POSEIDON, amongst past and future altimeter satellites) are detailed. The theoretical conclusions are illustrated with the numerical results of computer simulations. The nature of the errors in this type of orbits is such that this error can be filtered out by using height differences along repeating (overlapping) passes. This makes them particularly valuable for the study and monitoring of changes in the sea surface, such as tides. Elements of tidal theory, showing how these principles can be combined with those pertinent to the orbit error to make direct maps of the tides using altimetry are presented.

  1. Orbiter thermal protection system

    NASA Technical Reports Server (NTRS)

    Dotts, R. L.; Curry, D. M.; Tillian, D. J.

    1985-01-01

    The major material and design challenges associated with the orbiter thermal protection system (TPS), the various TPS materials that are used, the different design approaches associated with each of the materials, and the performance during the flight test program are described. The first five flights of the Orbiter Columbia and the initial flight of the Orbiter Challenger provided the data necessary to verify the TPS thermal performance, structural integrity, and reusability. The flight performance characteristics of each TPS material are discussed, based on postflight inspections and postflight interpretation of the flight instrumentation data. Flights to date indicate that the thermal and structural design requirements for the orbiter TPS are met and that the overall performance is outstanding.

  2. A tapestry of orbits

    SciTech Connect

    King-Hele, D.

    1992-01-01

    In this book, the author describes how orbital research developed to yield a rich harvest of knowledge about the earth and its atmosphere. King-Hele relates a personal account of this research based on analysis of satellite orbits between 1957 and 1990 conducted from the Royal Aircraft Establishment in Farnborough England. The early research methods used before the launch of Sputnik in 1957 are discussed.

  3. The orbit of Earth

    NASA Astrophysics Data System (ADS)

    Karna, S.; Mallik, A. K.

    2015-12-01

    In our solar system, the Earth's orbital plane is known as the ecliptic plane. The perihelion and aphelion distances, which are the closest and the farthest points from the Sun lie on the ecliptic plane. The distance between the Earth and Sun is not same throughout the year, i.e. the orbit of Earth deviates a bit from the circle. However, the difference between perihelion and aphelion distance is very small. The goal of our research was to see if changing the shapes or inclination of the earth's orbital plane makes any difference in the; axial tilt of Earth and Sun, the time period taken for the Sun to move from vernal equinox to autumnal equinox, and then back to the vernal equinox. For this, we constructed a 3-D numerical model of the Earth-Sun geometry. Our model defines Earth's orbit as an inclined plane of the spherically symmetric system. We calculated the degree of the tilt of earth orbit to the ecliptic plane by converting from ecliptic frame of reference to the orbital frame of reference and then we made all the measurements. Initial inputs for our model are aphelion and perihelion parameters. It is interesting to examine that our results obtained from the Earth inclined orbit is same that observed value from Earth's circular orbit. In other words, values of the axial tilt of Earth and Sun, the time taken for the Sun to move from vernal equinox to autumnal equinox, and then back to the vernal equinox does not change. Moreover, we were also able to derive mathematical relations for finding the length of the apparent solar days throughout the year. Our mathematical relation provides new insight for the calculation of the time for the revolution of Sun around the Galactic center.

  4. New Heteroclinic Orbits Coined

    NASA Astrophysics Data System (ADS)

    Wang, Haijun; Li, Chang; Li, Xianyi

    We devote to studying the problem for the existence of homoclinic and heteroclinic orbits of Unified Lorenz-Type System (ULTS). Other than the known results that the ULTS has two homoclinic orbits to E0 = (0, 0, 0) for b = -2a1, d = -a1, a12 + a 2c > 0, e < 0 and two heteroclinic orbits to E1,2 = (±-2(a1 2+a2 c) e ,∓a1 a2 -2(a1 2+a2 c) e ,-a12+a2c a2e ) for b = -2a1, d = -a1, a12 + a 2c < 0, e > 0 on its invariant algebraic surface Q(x,y,z) = z - x2 2a2 = 0, formulated in the literature by Yang and Chen [2014], we seize two new heteroclinic orbits of this Unified Lorenz-Type System. Namely, we rigorously prove that this system has another two heteroclinic orbits to E0 and E± = (±b(a2 c-a1 d) a1e ,∓a1 a2 b(a2 c-a1 d) a1e , a1d-a2c a2e ) while no homoclinic orbit when a1 < 0, e < 0, a1 + d < 0, a2≠0, a2c - a1d > 0, b + 2a1 ≥ 0.

  5. The Lunar Orbital Prospector

    NASA Technical Reports Server (NTRS)

    Redd, Frank J.; Cantrell, James N.; Mccurdy, Greg

    1992-01-01

    The establishment of lunar bases will not end the need for remote sensing of the lunar surface by orbiting platforms. Human and robotic surface exploration will necessarily be limited to some proximate distance from the support base. Near real-time, high-resolution, global characterization of the lunar surface by orbiting sensing systems will continue to be essential to the understanding of the Moon's geophysical structure and the location of exploitable minerals and deposits of raw materials. The Lunar Orbital Prospector (LOP) is an orbiting sensing platform capable of supporting a variety of modular sensing packages. Serviced by a lunar-based shuttle, the LOP will permit the exchange of instrument packages to meet evolving mission needs. The ability to recover, modify, and rotate sensing packages allows their reuse in varying combinations. Combining this flexibility with robust orbit modification capabilities and near real-time telemetry links provides considerable system responsiveness. Maintenance and modification of the LOP orbit are accomplished through use of an onboard propulsion system that burns lunar-supplied oxygen and aluminum. The relatively low performance of such a system is more than compensated for by the elimination of the need for Earth-supplied propellants. The LOP concept envisions a continuous expansion of capability through the incorporation of new instrument technologies and the addition of platforms.

  6. The Exoplanet Orbit Database

    NASA Astrophysics Data System (ADS)

    Wright, J. T.; Fakhouri, O.; Marcy, G. W.; Han, E.; Feng, Y.; Johnson, John Asher; Howard, A. W.; Fischer, D. A.; Valenti, J. A.; Anderson, J.; Piskunov, N.

    2011-04-01

    We present a database of well-determined orbital parameters of exoplanets, and their host stars’ properties. This database comprises spectroscopic orbital elements measured for 427 planets orbiting 363 stars from radial velocity and transit measurements as reported in the literature. We have also compiled fundamental transit parameters, stellar parameters, and the method used for the planets discovery. This Exoplanet Orbit Database includes all planets with robust, well measured orbital parameters reported in peer-reviewed articles. The database is available in a searchable, filterable, and sortable form online through the Exoplanets Data Explorer table, and the data can be plotted and explored through the Exoplanet Data Explorer plotter. We use the Data Explorer to generate publication-ready plots, giving three examples of the signatures of exoplanet migration and dynamical evolution: We illustrate the character of the apparent correlation between mass and period in exoplanet orbits, the different selection biases between radial velocity and transit surveys, and that the multiplanet systems show a distinct semimajor-axis distribution from apparently singleton systems.

  7. [Orbital complications of sinusitis].

    PubMed

    Šuchaň, M; Horňák, M; Kaliarik, L; Krempaská, S; Koštialová, T; Kovaľ, J

    2014-12-01

    Orbital complications categorised by Chandler are emergency. They need early diagnosis and agresive treatment. Stage and origin of orbital complications are identified by rhinoendoscopy, ophtalmologic examination and CT of orbite and paranasal sinuses. Periorbital cellulitis and early stage of orbital cellulitis can be treated conservatively with i. v. antibiotics. Monitoring of laboratory parameters and ophtalmologic symptoms is mandatory. Lack of improvement or worsening of symptoms within 24-48 hours and advanced stages of orbital complications are indicated for surgery. The purpose of the study is to evaluate epidemiology, clinical features and management of sinogenic orbital complications. Retrospective data of 8 patients with suspicion of orbital complication admited to hospital from 2008 to 2013 were evaluated. Patients were analyzed in terms of gender, age, CT findings, microbiology, clinical features, stage and treatment. Male and female were afected in rate 1,66:1. Most of patients were young adult in 3rd. and 4th. decade of life (62,5 %). Acute and chronic sinusitis were cause of orbital complication in the same rate. The most common origin of orbital complication was ethmoiditis (62,5 %), than maxillary (25 %) and frontal (12,5 %) sinusitis. Polysinusitis with affection of ethmoidal, maxillary and frontal sinuses (75 %) was usual CT finding. Staphylococcus epidermidis and Staphylococcus aureus were etiological agens in half of cases. Periorbital oedema (100 %), proptosis, chemosis (50 %), diplopia and glaucoma (12,5 %) were observed. Based on examinations, diagnosis of periorbital oedema/preseptal cellulitis was made in 3 (37,5 %), orbital cellulitis in 3 (37,5 %) and subperiosteal abscess in 2 cases (25 %). All patients underwent combined therapy - i. v. antibiotics and surgery within 24 hours. Eradication of disease from ostiomeatal complex (OMC), drainage of affected sinuses and drainage of subperiosteal abscess were done via fuctional endonasal

  8. Overall view of the Orbiter Servicing Structure within the Orbiter ...

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

    Overall view of the Orbiter Servicing Structure within the Orbiter Processing Facility at Kennedy Space Center. Can you see any hint of the Orbiter Discovery? It is in there. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  9. Mars Geoscience Orbiter and Lunar Geoscience Orbiter

    NASA Technical Reports Server (NTRS)

    Fuldner, W. V.; Kaskiewicz, P. F.

    1983-01-01

    The feasibility of using the AE/DE Earth orbiting spacecraft design for the LGO and/or MGO missions was determined. Configurations were developed and subsystems analysis was carried out to optimize the suitability of the spacecraft to the missions. The primary conclusion is that the basic AE/DE spacecraft can readily be applied to the LGO mission with relatively minor, low risk modifications. The MGO mission poses a somewhat more complex problem, primarily due to the overall maneuvering hydrazine budget and power requirements of the sensors and their desired duty cycle. These considerations dictate a modification (scaling up) of the structure to support mission requirements.

  10. Orbital Fluid Resupply Assessment

    NASA Technical Reports Server (NTRS)

    Eberhardt, Ralph N.

    1989-01-01

    Orbital fluid resupply can significantly increase the cost-effectiveness and operational flexibility of spacecraft, satellites, and orbiting platforms and observatories. Reusable tankers are currently being designed for transporting fluids to space. A number of options exist for transporting the fluids and propellant to the space-based user systems. The fluids can be transported to space either in the Shuttle cargo bay or using expendable launch vehicles (ELVs). Resupply can thus be accomplished either from the Shuttle bay, or the tanker can be removed from the Shuttle bay or launched on an ELV and attached to a carrier such as the Orbital Maneuvering Vehicle (OMV) or Orbital Transfer Vehicle (OTV) for transport to the user to be serviced. A third option involves locating the tanker at the space station or an unmanned platform as a quasi-permanent servicing facility or depot which returns to the ground for recycling once its tanks are depleted. Current modular tanker designs for monopropellants, bipropellants, and water for space station propulsion are discussed. Superfluid helium tankers are addressed, including trade-offs in tanker sizes, shapes to fit the range of ELVs currently available, and boil-off losses associated with longer-term (greater than 6-month) space-basing. It is concluded that the mixed fleet approach to on-orbit consumables resupply offers significant advantages to the overall logistics requirements.

  11. Sedna Orbit Comparisons

    NASA Technical Reports Server (NTRS)

    2004-01-01

    These four panels show the location of the newly discovered planet-like object, dubbed 'Sedna,' which lies in the farthest reaches of our solar system. Each panel, moving counterclockwise from the upper left, successively zooms out to place Sedna in context. The first panel shows the orbits of the inner planets, including Earth, and the asteroid belt that lies between Mars and Jupiter. In the second panel, Sedna is shown well outside the orbits of the outer planets and the more distant Kuiper Belt objects. Sedna's full orbit is illustrated in the third panel along with the object's current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. The final panel zooms out much farther, showing that even this large elliptical orbit falls inside what was previously thought to be the inner edge of the Oort cloud. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed.

  12. Sedna Orbit Comparisons

    NASA Image and Video Library

    2004-03-15

    These four panels show the location of the newly discovered planet-like object, dubbed "Sedna," which lies in the farthest reaches of our solar system. Each panel, moving counterclockwise from the upper left, successively zooms out to place Sedna in context. The first panel shows the orbits of the inner planets, including Earth, and the asteroid belt that lies between Mars and Jupiter. In the second panel, Sedna is shown well outside the orbits of the outer planets and the more distant Kuiper Belt objects. Sedna's full orbit is illustrated in the third panel along with the object's current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. The final panel zooms out much farther, showing that even this large elliptical orbit falls inside what was previously thought to be the inner edge of the Oort cloud. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed. http://photojournal.jpl.nasa.gov/catalog/PIA05569

  13. Sedna Orbit Comparisons

    NASA Technical Reports Server (NTRS)

    2004-01-01

    These four panels show the location of the newly discovered planet-like object, dubbed 'Sedna,' which lies in the farthest reaches of our solar system. Each panel, moving counterclockwise from the upper left, successively zooms out to place Sedna in context. The first panel shows the orbits of the inner planets, including Earth, and the asteroid belt that lies between Mars and Jupiter. In the second panel, Sedna is shown well outside the orbits of the outer planets and the more distant Kuiper Belt objects. Sedna's full orbit is illustrated in the third panel along with the object's current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. The final panel zooms out much farther, showing that even this large elliptical orbit falls inside what was previously thought to be the inner edge of the Oort cloud. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed.

  14. Orbital spacecraft resupply technology

    NASA Technical Reports Server (NTRS)

    Eberhardt, R. N.; Tracey, T. R.; Bailey, W. J.

    1986-01-01

    The resupplying of orbital spacecraft using the Space Shuttle, Orbital Maneuvering Vehicle, Orbital Transfer Vehicle or a depot supply at a Space Station is studied. The governing factor in fluid resupply designs is the system size with respect to fluid resupply quantities. Spacecraft propellant management for tankage via diaphragm or surface tension configurations is examined. The capabilities, operation, and application of adiabatic ullage compression, ullage exchange, vent/fill/repressurize, and drain/vent/no-vent fill/repressurize, which are proposed transfer methods for spacecraft utilizing tankage configurations, are described. Selection of the appropriate resupply method is dependent on the spacecraft design features. Hydrazine adiabatic compression/detonation, liquid-free vapor venting to prevent freezing, and a method for no-vent liquid filling are analyzed. Various procedures for accurate measurements of propellant mass in low gravity are evaluated; a system of flowmeters with a PVT system was selected as the pressurant solubility and quantity gaging technique. Monopropellant and bipropellant orbital spacecraft consumable resupply system tanks which resupply 3000 lb of hydrazine and 7000 lb of MMH/NTO to spacecraft on orbit are presented.

  15. Orbits For Sixteen Binaries

    NASA Astrophysics Data System (ADS)

    Cvetkovic, Z.; Novakovic, B.

    2006-12-01

    In this paper orbits for 13 binaries are recalculated and presented. The reason is that recent observations show higher residuals than the corresponding ephemerides calculated by using the orbital elements given in the Sixth Catalog of Orbits of Visual Binary Stars. The binaries studied were: WDS 00182+7257 = A 803, WDS 00335+4006 = HO 3, WDS 00583+2124 = BU 302, WDS 01011+6022 = A 926, WDS 01014+1155 = BU 867, WDS 01112+4113 = A 655, WDS 01361-2954 + HJ 3447, WDS 02333+5219 = STT 42 AB, WDS 04362+0814 = A 1840 AB, WDS 08017-0836 = A 1580, WDS 08277-0425 = A 550, WDS 17471+1742 = STF 2215 and WDS 18025+4414 = BU 1127 Aa-B. In addition, for three binaries - WDS 01532+1526 = BU 260, WDS 02563+7253 =STF 312 AB and WDS 05003+3924 = STT 92 AB - the orbital elements are calculated for the first time. In this paper the authors present not only the orbital elements, but the masses, dynamical parallaxes, absolute magnitudes and ephemerides for the next five years, as well.

  16. 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.

  17. 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.

  18. [Secondary orbital lymphoma].

    PubMed

    Basanta, I; Sevillano, C; Álvarez, M D

    2015-09-01

    A case is presented of an 85 year-old Caucasian female with lymphoma that recurred in the orbit (secondary ocular adnexal lymphoma). The orbital tumour was a diffuse large B-cell lymphoma according to the REAL classification (Revised European-American Lymphoma Classification). Orbital lymphomas are predominantly B-cell proliferations of a variety of histological types, and most are low-grade tumours. Patients are usually middle-aged or elderly, and it is slightly more common in women. A palpable mass, proptosis and blepharoptosis are the most common signs of presentation. Copyright © 2011 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  19. Antares Orbital-3 Mission

    NASA Image and Video Library

    2014-10-27

    The Orbital Sciences Corporation Antares rocket, with the Cygnus spacecraft onboard, is seen on launch Pad-0A after the launch attempt was scrubbed because of a boat down range in the trajectory Antares would have flown had it lifted off, Monday, Oct. 27, 2014, at NASA's Wallops Flight Facility in Virginia. The Antares will launch with the Cygnus spacecraft filled with over 5,000 pounds of supplies for the International Space Station, including science experiments, experiment hardware, spare parts, and crew provisions. The Orbital-3 mission is Orbital Sciences' third contracted cargo delivery flight to the space station for NASA. The next launch attempt will be made on Tuesday, Oct. 28 at 6:22 p.m. EDT. Photo Credit: (NASA/Joel Kowsky)

  20. Vertical orbital dystopia.

    PubMed

    Tan, S T; Ashworth, G; Czypionka, S; Poole, M D; Briggs, M

    1996-06-01

    Many pathologic processes may lead to vertical orbital dystopia. We reviewed 47 consecutive cases seen over a 13-year period. Twenty-nine patients underwent eye leveling procedures to improve cosmesis, 2 of these by camouflage procedures and 27 by orbital translocation. Ten patients had 16 secondary operations. There was one death, serious complications occurred in 3 patients, and nuisance complications occurred in 20 others. Seven patients developed diplopia postoperatively, and in 6 patients it was troublesome. In these, it resolved fully in 2 patients, improved to be of no consequence in 2, and in the remaining 2 troublesome symptoms persisted requiring inferior oblique muscle recession in 1. Binocular vision was never restored when not present preoperatively, and in 3 patients temporary loss occurred. There was an overall modest but significant improvement in appearance after surgery. It is concluded that vertical orbital translocation is rewarding and worthwhile.

  1. Deceleration Orbit Improvements

    SciTech Connect

    Church, M.

    1991-04-26

    During the accelerator studies period of 12/90-1/91 much study time was dedicated to improving the E760 deceleration ramps. 4 general goals were in mind: (1) Reduce the relative orbit deviations from the nominal reference orbit as much as possible. This reduces the potential error in the orbit length calculation - which is the primary source of error in the beam energy calculation. (2) Maximize the transverse apertures. This minimizes beam loss during deceleration and during accidental beam blow-ups. (3) Measure and correct lattice parameters. Knowledge of {gamma}{sub T}, {eta}, Q{sub h}, Q{sub v}, and the dispersion in the straight sections allows for a more accurate energy calculation and reliable SYNCH calculations. (4) Minimize the coupling. This allows one to discern between horizontal and vertical tunes.

  2. Spiral Orbit Tribometer

    NASA Technical Reports Server (NTRS)

    Pepper, Stephen V.; Jones, William R., Jr.; Kingsbury, Edward; Jansen, Mark J.

    2007-01-01

    The spiral orbit tribometer (SOT) bridges the gap between full-scale life testing and typically unrealistic accelerated life testing of ball-bearing lubricants in conjunction with bearing ball and race materials. The SOT operates under realistic conditions and quickly produces results, thereby providing information that can guide the selection of lubricant, ball, and race materials early in a design process. The SOT is based upon a simplified, retainerless thrust bearing comprising one ball between flat races (see figure). The SOT measures lubricant consumption and degradation rates and friction coefficients in boundary lubricated rolling and pivoting contacts. The ball is pressed between the lower and upper races with a controlled force and the lower plate is rotated. The combination of load and rotation causes the ball to move in a nearly circular orbit that is, more precisely, an opening spiral. The spiral s pitch is directly related to the friction coefficient. At the end of the orbit, the ball contacts the guide plate, restoring the orbit to its original radius. The orbit is repeatable throughout the entire test. A force transducer, mounted in-line with the guide plate, measures the force between the ball and the guide plate, which directly relates to the friction coefficient. The SOT, shown in the figure, can operate in under ultra-high vacuum (10(exp -9) Torr) or in a variety of gases at atmospheric pressure. The load force can be adjusted between 45 and 450 N. By varying the load force and ball diameter, mean Hertzian stresses between 0.5 and 5.0 GPa can be obtained. The ball s orbital speed range is between 1 and 100 rpm.

  3. Satellite orbit predictor

    NASA Technical Reports Server (NTRS)

    Friedman, Morton l.; Garrett, James, Major

    An analog aid to determine satellite coverage of Emergency Locator Transmitters Emergency Position Indicating Radio Beacon (ELT/EPIRB) distress incidence is discussed. The satellite orbit predictor is a graphical aid for determining the relationship between the satellite orbit, antenna coverage of the spacecraft and coverage of the Local User Terminal. The predictor allows the user to quickly visualize if a selected position will probably be detected and is composed of a base map and a satellite track overlay for each satellite.A table of equator crossings for each satellite is included.

  4. Optical orbital angular momentum.

    PubMed

    Barnett, Stephen M; Babiker, Mohamed; Padgett, Miles J

    2017-02-28

    We present a brief introduction to the orbital angular momentum of light, the subject of our theme issue and, in particular, to the developments in the 13 years following the founding paper by Allen et al. (Allen et al. 1992 Phys. Rev. A 45, 8185 (doi:10.1103/PhysRevA.45.8185)). The papers by our invited authors serve to bring the field up to date and suggest where developments may take us next.This article is part of the themed issue 'Optical orbital angular momentum'.

  5. Passive orbital disconnect strut

    NASA Technical Reports Server (NTRS)

    Parmley, R. T.; Kittel, P.

    1984-01-01

    The design and test results with a third generation passive orbital disconnect strut (PODS) for space-based cryogenic He dewars are presented. Three pairs of PODS struts support a tank and change lengths in response to gas and temperature changes. A thin wall fiberglass tube is used on the cold disconnect end, which can be operated on the ground or in space. Tests were performed to characterize heat flows across the cold end to a liquid He sink and subsequent vacuum pressure within the He tank. Heat transfer was lower than predicted, suggesting that longer dewar in-orbit lifetimes can be expected with the new PODS.

  6. Optical orbital angular momentum

    PubMed Central

    Barnett, Stephen M.; Babiker, Mohamed; Padgett, Miles J.

    2017-01-01

    We present a brief introduction to the orbital angular momentum of light, the subject of our theme issue and, in particular, to the developments in the 13 years following the founding paper by Allen et al. (Allen et al. 1992 Phys. Rev. A 45, 8185 (doi:10.1103/PhysRevA.45.8185)). The papers by our invited authors serve to bring the field up to date and suggest where developments may take us next. This article is part of the themed issue ‘Optical orbital angular momentum’. PMID:28069775

  7. Pediatric Orbital Fractures

    PubMed Central

    Oppenheimer, Adam J.; Monson, Laura A.; Buchman, Steven R.

    2013-01-01

    It is wise to recall the dictum “children are not small adults” when managing pediatric orbital fractures. In a child, the craniofacial skeleton undergoes significant changes in size, shape, and proportion as it grows into maturity. Accordingly, the craniomaxillofacial surgeon must select an appropriate treatment strategy that considers both the nature of the injury and the child's stage of growth. The following review will discuss the management of pediatric orbital fractures, with an emphasis on clinically oriented anatomy and development. PMID:24436730

  8. Optical orbital angular momentum

    NASA Astrophysics Data System (ADS)

    Barnett, Stephen M.; Babiker, Mohamed; Padgett, Miles J.

    2017-02-01

    We present a brief introduction to the orbital angular momentum of light, the subject of our theme issue and, in particular, to the developments in the 13 years following the founding paper by Allen et al. (Allen et al. 1992 Phys. Rev. A 45, 8185 (doi:10.1103/PhysRevA.45.8185)). The papers by our invited authors serve to bring the field up to date and suggest where developments may take us next. This article is part of the themed issue 'Optical orbital angular momentum'.

  9. ARTEMIS Lunar Orbit Insertion and Science Orbit Design Through 2013

    NASA Technical Reports Server (NTRS)

    Broschart, Stephen B.; Sweetser, Theodore H.; Angelopoulos, Vassilis; Folta, David; Woodard, Mark

    2015-01-01

    As of late-July 2011, the ARTEMIS mission is transferring two spacecraft from Lissajous orbits around Earth-Moon Lagrange Point #1 into highly-eccentric lunar science orbits. This paper presents the trajectory design for the transfer from Lissajous orbit to lunar orbit insertion, the period reduction maneuvers, and the science orbits through 2013. The design accommodates large perturbations from Earth's gravity and restrictive spacecraft capabilities to enable opportunities for a range of heliophysics and planetary science measurements. The process used to design the highly-eccentric ARTEMIS science orbits is outlined. The approach may inform the design of future planetary moon missions.

  10. ARTEMIS Lunar Orbit Insertion and Science Orbit Design Through 2013

    NASA Technical Reports Server (NTRS)

    Broschart, Stephen B.; Sweetser, Theodore H.; Angelopoulos, Vassilis; Folta, David; Woodard, Mark

    2015-01-01

    As of late-July 2011, the ARTEMIS mission is transferring two spacecraft from Lissajous orbits around Earth-Moon Lagrange Point #1 into highly-eccentric lunar science orbits. This paper presents the trajectory design for the transfer from Lissajous orbit to lunar orbit insertion, the period reduction maneuvers, and the science orbits through 2013. The design accommodates large perturbations from Earth's gravity and restrictive spacecraft capabilities to enable opportunities for a range of heliophysics and planetary science measurements. The process used to design the highly-eccentric ARTEMIS science orbits is outlined. The approach may inform the design of future planetary moon missions.

  11. Europa Orbiter Exploration Strategies

    NASA Technical Reports Server (NTRS)

    Johnson, T. V.

    2001-01-01

    The Europa Orbiter mission is planned as the next stage of Europa exploration. Its primary goals are to search for definitive evidence of a subsurface ocean, to characterize the ice crust and ice/water interface, and to prepare for future surface/sub-surface missions. Additional information is contained in the original extended abstract.

  12. A Neptune Orbiter Mission

    NASA Technical Reports Server (NTRS)

    Wallace, R. A.; Spilker, T. R.

    1998-01-01

    This paper describes the results of new analyses and mission/system designs for a low cost Neptune Orbiter mission. Science and measurement objectives, instrumentation, and mission/system design options are described and reflect an aggressive approach to the application of new advanced technologies expected to be available and developed over the next five to ten years.

  13. [Orbital neoplasms in children].

    PubMed

    Küchle, H J

    1989-04-01

    The incidence, diagnosis and clinical picture of the orbital tumors in children are discussed on the basis of 49 personal cases. Discovered was the preponderance of primary non-malignant tumors. The most frequently encountered tumors were angiomas (27 p.c.), dermatomas (19 p.c.) lymphomas (8 p.c.) and among the malignant tumors--rhabdomyosarcoma (6 p.c.).

  14. Electrostatic drops in orbit

    NASA Astrophysics Data System (ADS)

    Rodriguez, Isabel J.; Schmidt, Erin; Weislogel, Mark M.; Pettit, Donald

    2016-11-01

    We present what we think are the first intentional electrostatic orbits in the near-weightless environment of a drop tower. Classical physics problems involving Coulombic forces in orbital mechanics have traditionally been confined to thought experiments due to practical terrestrial experimental limitations, namely, the preponderance of gravity. However, the use of a drop tower as an experimental platform can overcome this challenge for brief periods. We demonstrate methanol-water droplets in orbit around a variety of charged objects- some of which can be used to validate special cases of N-body systems. Footage collected via a high-speed camera is analyzed and orbital trajectories are compared with existing theoretical predictions. Droplets of diameters 0.5 to 2mm in a variety of obits are observed. Due to the repeatability of drop tower initial conditions and effective low-g environment, such experiments may be used to construct empirical analogues and confirm analyses toward the benefit of other fields including space and planetary science. NASA Cooperative Agreement NNX12A047A, Portland State LSAMP, Robert E. McNair Scholars Program.

  15. Mars Climate Orbiter

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Mars Surveyor '98 Climate Orbiter is shown here during acoustic tests that simulate launch conditions. The orbiter was to conduct a two year primary mission to profile the Martian atmosphere and map the surface. To carry out these scientific objectives, the spacecraft carried a rebuilt version of the pressure modulated infrared radiometer, lost with the Mars Observer spacecraft, and a miniaturized dual camera system the size of a pair of binoculars, provided by Malin Space Science Systems, Inc., San Diego, California. During its primary mission, the orbiter was to monitor Mars atmosphere and surface globally on a daily basis for one Martian year (two Earth years), observing the appearance and movement of atmospheric dust and water vapor, as well as characterizing seasonal changes of the planet's surface. Imaging of the surface morphology would also provide important clues about the planet's climate in its early history. The mission was part of NASA's Mars Surveyor program, a sustained program of robotic exploration of the red planet, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, DC. Lockheed Martin Astronautics was NASA's industrial partner in the mission. Unfortunately, Mars Climate Orbiter burned up in the Martian atmosphere on September 23, 1999, due to a metric conversion error that caused the spacecraft to be off course.

  16. Sedna Orbit Animation

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This animation shows the location of the newly discovered planet-like object, dubbed 'Sedna,' in relation to the rest of the solar system. Starting at the inner solar system, which includes the orbits of Mercury, Venus, Earth, and Mars (all in yellow), the view pulls away through the asteroid belt and the orbits of the outer planets beyond (green). Pluto and the distant Kuiper Belt objects are seen next until finally Sedna comes into view. As the field widens the full orbit of Sedna can be seen along with its current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. Moving past Sedna, what was previously thought to be the inner edge of the Oort cloud appears. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed.

  17. Sedna Orbit Animation

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This animation shows the location of the newly discovered planet-like object, dubbed 'Sedna,' in relation to the rest of the solar system. Starting at the inner solar system, which includes the orbits of Mercury, Venus, Earth, and Mars (all in yellow), the view pulls away through the asteroid belt and the orbits of the outer planets beyond (green). Pluto and the distant Kuiper Belt objects are seen next until finally Sedna comes into view. As the field widens the full orbit of Sedna can be seen along with its current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. Moving past Sedna, what was previously thought to be the inner edge of the Oort cloud appears. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed.

  18. Solar Orbiter Status Report

    NASA Astrophysics Data System (ADS)

    Gilbert, Holly; St. Cyr, Orville Chris; Mueller, Daniel; Zouganelis, Yannis; Velli, Marco

    2017-08-01

    With the delivery of the instruments to the spacecraft builder, the Solar Orbiter mission is in the midst of Integration & Testing phase at Airbus in Stevenage, U.K. This mission to “Explore the Sun-Heliosphere Connection” is the first medium-class mission of ESA’s Cosmic Vision 2015-2025 program and is being jointly implemented with NASA. The dedicated payload of 10 remote-sensing and in-situ instruments will orbit the Sun as close as 0.3 A.U. and will provide measurments from the photosphere into the solar wind. The three-axis stabilized spacecraft will use Venus gravity assists to increase the orbital inclination out of the ecliptic to solar latitudes as high as 34 degrees in the extended mission. The science team of Solar Orbiter has been working closely with the Solar Probe Plus scientists to coordinate observations between these two highly-complementary missions. This will be a status report on the mission development; the interested reader is referred to the recent summary by Müller et al., Solar Physics 285 (2013).

  19. Orbital Fluid Transfer System

    NASA Technical Reports Server (NTRS)

    Johnston, A. S., (Nick); Ryder, Mel; Tyler, Tony R.

    1998-01-01

    An automated fluid and power interface system needs to be developed for future space missions which require on orbit consumable replenishment. Current method of fluid transfer require manned vehicles and extravehicular activity. Currently the US does not have an automated capability for consumable transfer on-orbit. This technology would benefit both Space Station and long duration satellites. In order to provide this technology the Automated Fluid Interface System (AFIS) was developed. The AFIS project was an advanced development program aimed at developing a prototype satellite servicer for future space operations. This mechanism could transfer propellants, cryogens, fluids, gasses, electrical power, and communications from a tanker unit to the orbiting satellite. The development of this unit was a cooperative effort between Marshall Space Flight Center in Huntsville, Alabama, and Moog, Inc. in East Aurora, New York. An engineering model was built and underwent substantial development testing at Marshall Space Flight Center (MSFC). While the AFIS is not suitable for spaceflight, testing and evaluation of the AFIS provided significant experience which would be beneficial in building a flight unit. The lessons learned from testing the AFIS provided the foundation for the next generation fluid transfer mechanism, the Orbital Fluid Transfer System (OFTS). The OFTS project was a study contract with MSFC and Moog, Inc. The OFTS was designed for the International Space Station (ISS), but its flexible design could used for long duration satellite missions and other applications. The OFTS was designed to be used after docking. The primary function was to transfer bipropellants and high pressure gases. The other items addressed by this task included propellant storage, hardware integration, safety and control system issues. A new concept for high pressure couplings was also developed. The results of the AFIS testing provided an excellent basis for the OFTS design. The OFTS

  20. Orbital Fluid Transfer System

    NASA Technical Reports Server (NTRS)

    Johnston, A. S., (Nick); Ryder, Mel; Tyler, Tony R.

    1998-01-01

    An automated fluid and power interface system needs to be developed for future space missions which require on orbit consumable replenishment. Current method of fluid transfer require manned vehicles and extravehicular activity. Currently the US does not have an automated capability for consumable transfer on-orbit. This technology would benefit both Space Station and long duration satellites. In order to provide this technology the Automated Fluid Interface System (AFIS) was developed. The AFIS project was an advanced development program aimed at developing a prototype satellite servicer for future space operations. This mechanism could transfer propellants, cryogens, fluids, gasses, electrical power, and communications from a tanker unit to the orbiting satellite. The development of this unit was a cooperative effort between Marshall Space Flight Center in Huntsville, Alabama, and Moog, Inc. in East Aurora, New York. An engineering model was built and underwent substantial development testing at Marshall Space Flight Center (MSFC). While the AFIS is not suitable for spaceflight, testing and evaluation of the AFIS provided significant experience which would be beneficial in building a flight unit. The lessons learned from testing the AFIS provided the foundation for the next generation fluid transfer mechanism, the Orbital Fluid Transfer System (OFTS). The OFTS project was a study contract with MSFC and Moog, Inc. The OFTS was designed for the International Space Station (ISS), but its flexible design could used for long duration satellite missions and other applications. The OFTS was designed to be used after docking. The primary function was to transfer bipropellants and high pressure gases. The other items addressed by this task included propellant storage, hardware integration, safety and control system issues. A new concept for high pressure couplings was also developed. The results of the AFIS testing provided an excellent basis for the OFTS design. The OFTS

  1. CO-ORBITAL OLIGARCHY

    SciTech Connect

    Collins, Benjamin F.; Sari, Re'em

    2009-04-15

    We present a systematic examination of the changes in semimajor axis of a protoplanet as it interacts with other protoplanets in the presence of eccentricity dissipation. For parameters relevant to the oligarchic stage of planet formation, dynamical friction keeps the typical eccentricities small and prevents orbit crossing. Interactions at impact parameters greater than several Hill radii cause the protoplanets to repel each other; if the impact parameter is instead much less than the Hill radius, the protoplanets shift slightly in semimajor axis but remain otherwise unperturbed. If the orbits of two or more protoplanets are separated by less than a Hill radius, they are each pushed toward an equilibrium spacing between their neighbors and can exist as a stable co-orbital system. In the shear-dominated oligarchic phase of planet formation, we show that the feeding zones contain several oligarchs instead of only one. Growth of the protoplanets in the oligarchic phase drives the disk to an equilibrium configuration that depends on the mass ratio of protoplanets to planetesimals, {sigma}/{sigma}. Early in the oligarchic phase, when {sigma}/{sigma} is low, the spacing between rows of co-orbital oligarchs are about 5 Hill radii wide, rather than the 10 Hill radii cited in the literature. It is likely that at the end of oligarchy, the average number of co-orbital oligarchs is greater than unity. In the outer solar system, this raises the disk mass required to form the ice giants. In the inner solar system, this lowers the mass of the final oligarchs and requires more giant impacts than previously estimated. This result provides additional evidence that Mars is not an untouched leftover from the oligarchic phase, but must be composed of several oligarchs assembled through giant impacts.

  2. Co-Orbital Oligarchy

    NASA Astrophysics Data System (ADS)

    Collins, Benjamin F.; Sari, Re'em

    2009-04-01

    We present a systematic examination of the changes in semimajor axis of a protoplanet as it interacts with other protoplanets in the presence of eccentricity dissipation. For parameters relevant to the oligarchic stage of planet formation, dynamical friction keeps the typical eccentricities small and prevents orbit crossing. Interactions at impact parameters greater than several Hill radii cause the protoplanets to repel each other; if the impact parameter is instead much less than the Hill radius, the protoplanets shift slightly in semimajor axis but remain otherwise unperturbed. If the orbits of two or more protoplanets are separated by less than a Hill radius, they are each pushed toward an equilibrium spacing between their neighbors and can exist as a stable co-orbital system. In the shear-dominated oligarchic phase of planet formation, we show that the feeding zones contain several oligarchs instead of only one. Growth of the protoplanets in the oligarchic phase drives the disk to an equilibrium configuration that depends on the mass ratio of protoplanets to planetesimals, Σ/σ. Early in the oligarchic phase, when Σ/σ is low, the spacing between rows of co-orbital oligarchs are about 5 Hill radii wide, rather than the 10 Hill radii cited in the literature. It is likely that at the end of oligarchy, the average number of co-orbital oligarchs is greater than unity. In the outer solar system, this raises the disk mass required to form the ice giants. In the inner solar system, this lowers the mass of the final oligarchs and requires more giant impacts than previously estimated. This result provides additional evidence that Mars is not an untouched leftover from the oligarchic phase, but must be composed of several oligarchs assembled through giant impacts.

  3. Comparison of Low Earth Orbit and Geosynchronous Earth Orbits

    NASA Technical Reports Server (NTRS)

    Drummond, J. E.

    1980-01-01

    The technological, environmental, social, and political ramifications of low Earth orbits as compared to geosynchronous Earth orbits for the solar power satellite (SPS) are assessed. The capital cost of the transmitting facilities is dependent on the areas of the antenna and rectenna relative to the requirement of high efficiency power transmission. The salient features of a low orbit Earth orbits are discussed in terms of cost reduction efforts.

  4. Shuttle on-orbit rendezvous targeting: Circular orbits

    NASA Technical Reports Server (NTRS)

    Bentley, E. L.

    1972-01-01

    The strategy and logic used in a space shuttle on-orbit rendezvous targeting program are described. The program generates ascent targeting conditions for boost to insertion into an intermediate parking orbit, and generates on-orbit targeting and timeline bases for each maneuver to effect rendezvous with a space station. Time of launch is determined so as to eliminate any plane change, and all work was performed for a near-circular space station orbit.

  5. Helioseismology with Solar Orbiter

    NASA Astrophysics Data System (ADS)

    Löptien, Björn; Birch, Aaron C.; Gizon, Laurent; Schou, Jesper; Appourchaux, Thierry; Blanco Rodríguez, Julián; Cally, Paul S.; Dominguez-Tagle, Carlos; Gandorfer, Achim; Hill, Frank; Hirzberger, Johann; Scherrer, Philip H.; Solanki, Sami K.

    2015-12-01

    The Solar Orbiter mission, to be launched in July 2017, will carry a suite of remote sensing and in-situ instruments, including the Polarimetric and Helioseismic Imager (PHI). PHI will deliver high-cadence images of the Sun in intensity and Doppler velocity suitable for carrying out novel helioseismic studies. The orbit of the Solar Orbiter spacecraft will reach a solar latitude of up to 21∘ (up to 34∘ by the end of the extended mission) and thus will enable the first local helioseismology studies of the polar regions. Here we consider an array of science objectives to be addressed by helioseismology within the baseline telemetry allocation (51 Gbit per orbit, current baseline) and within the science observing windows (baseline 3×10 days per orbit). A particularly important objective is the measurement of large-scale flows at high latitudes (rotation and meridional flow), which are largely unknown but play an important role in flux transport dynamos. For both helioseismology and feature tracking methods convection is a source of noise in the measurement of longitudinally averaged large-scale flows, which decreases as T -1/2 where T is the total duration of the observations. Therefore, the detection of small amplitude signals (e.g., meridional circulation, flows in the deep solar interior) requires long observation times. As an example, one hundred days of observations at lower spatial resolution would provide a noise level of about three m/s on the meridional flow at 80∘ latitude. Longer time-series are also needed to study temporal variations with the solar cycle. The full range of Earth-Sun-spacecraft angles provided by the orbit will enable helioseismology from two vantage points by combining PHI with another instrument: stereoscopic helioseismology will allow the study of the deep solar interior and a better understanding of the physics of solar oscillations in both quiet Sun and sunspots. We have used a model of the PHI instrument to study its

  6. SPECS: Orbital debris removal

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The debris problem has reached a stage at which the risk to satellites and spacecraft has become substantial in low Earth orbit (LEO). This research discovered that small particles posed little threat to spacecraft because shielding can effectively prevent these particles from damaging the spacecraft. The research also showed that, even though collision with a large piece of debris could destroy the spacecraft, the large pieces of debris pose little danger because they can be tracked and the spacecraft can be maneuvered away from these pieces. Additionally, there are many current designs to capture and remove large debris particles from the space environment. From this analysis, it was decided to concentrate on the removal of medium-sized orbital debris, that is, those pieces ranging from 1 cm to 50 cm in size. The current design incorporates a transfer vehicle and a netting vehicle to capture the medium-sized debris. The system is based near an operational space station located at 28.5 deg inclination and 400 km altitude. The system uses ground-based tracking to determine the location of a satellite breakup or debris cloud. These data are uploaded to the transfer vehicle, which proceeds to rendezvous with the debris at a lower altitude parking orbit. Next, the netting vehicle is deployed, tracks the targeted debris, and captures it. After expending the available nets, the netting vehicle returns to the transfer vehicle for a new netting module and continues to capture more debris in the target area. Once all the netting modules are expended, the transfer vehicle returns to the space station's orbit where it is resupplied with new netting modules from a space shuttle load. The new modules are launched by the shuttle from the ground and the expended modules are taken back to Earth for removal of the captured debris, refueling, and repacking of the nets. Once the netting modules are refurbished, they are taken back into orbit for reuse. In a typical mission, the

  7. Close up view of the Orbiter Discovery in the Orbiter ...

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

    Close up view of the Orbiter Discovery in the Orbiter Processing Facility at Kennedy Space Center. The view is a detail of the aft, starboard landing gear and a general view of the Thermal Protection System tiles around the landing-gear housing. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  8. Orbit Insertion by Mars Reconnaissance Orbiter (Artist's Concept)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This is an artist's concept of NASA's Mars Reconnaissance Orbiter during the critical process of Mars orbit insertion. In order to be captured into orbit around Mars, the spacecraft must conduct a 25-minute rocket burn when it is just shy of reaching the planet. As pictured, it will pass under the red planet's southern hemisphere as it begins the insertion burn.

  9. Lunar Reconnaissance Orbiter Mission Highlights

    NASA Image and Video Library

    Since launch on June 18, 2009 as a precursor mission, the Lunar Reconnaissance Orbiter (LRO) has remained in orbit around the moon, collecting vast amounts of science data in support of NASA's expl...

  10. Diverse Orbits Around Mars Graphic

    NASA Image and Video Library

    2015-05-04

    This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet's two natural satellites. It illustrates the potential for intersections of the spacecraft orbits. The number of active orbiter missions at Mars increased from three to five in 2014. With the increased traffic, NASA has augmented a process for anticipating orbit intersections and avoiding collisions. NASA's Mars Odyssey and MRO (Mars Reconnaissance Orbiter) travel near-circular orbits. The European Space Agency's Mars Express, NASA's MAVEN (Mars Atmosphere and Volatile Evolution) and India's MOM (Mars Orbiter Mission), travel more elliptical orbits. Phobos and Deimos are the two natural moons of Mars. http://photojournal.jpl.nasa.gov/catalog/PIA19396

  11. Diplopia secondary to orbital surgery.

    PubMed

    Silbert, David I; Matta, Noelle S; Singman, Eric L

    2012-01-01

    Diplopia may occur following any type of ocular or pericocular surgery. The surgeries most frequently associated with postoperative diplopia include: repair of orbital fracture, endoscopic sinus surgery (from inadvertent orbital penetration), and orbital decompression for thyroid-related immune orbitopathy (TRIO). Postoperative diplopia after orbital tumor resection has been reported--e.g., after excision of fibrous dysplasia and osteoma. However, a recent case series suggests diplopia after orbital tumor resection is uncommon and transient. Surgical intervention for orbital trauma carries the highest risk of postoperative diplopia and will be the focus of this review. We will also present a case report of worsening diplopia following repair of orbital floor fracture to highlight potential motility issues that can arise when implants are employed to treat orbital floor fractures.

  12. The Orbital Acceleration Research Experiment

    NASA Technical Reports Server (NTRS)

    Blanchard, R. C.; Hendrix, M. K.; Fox, J. C.; Thomas, D. J.; Nicholson, J.

    1986-01-01

    The hardware and software of NASA's proposed Orbital Acceleration Research Experiment (OARE) are described. The OARE is to provide aerodynamic acceleration measurements along the Orbiter's principal axis in the free-molecular flow-flight regime at orbital attitude and in the transition regime during reentry. Models considering the effects of electromagnetic effects, solar radiation pressure, orbiter mass attraction, gravity gradient, orbital centripetal acceleration, out-of-orbital-plane effects, orbiter angular velocity, structural noise, mass expulsion signal sources, crew motion, and bias on acceleration are examined. The experiment contains an electrostatically balanced cylindrical proofmass accelerometer sensor with three orthogonal sensing axis outputs. The components and functions of the experimental calibration system and signal processor and control subsystem are analyzed. The development of the OARE software is discussed. The experimental equipment will be enclosed in a cover assembly that will be mounted in the Orbiter close to the center of gravity.

  13. Orbiter based construction equipment

    NASA Technical Reports Server (NTRS)

    Goodwin, C. J.

    1982-01-01

    Many orbiter based activities need equipment to hold a payload steady while it is being worked on. This work may be construction, updating, repair, services, check out, or refueling operations in preparation for return to Earth. The Handling and Positioning Aid (HPA) is intended for use as general purpose equipment. The HPA provides a wide choice of work station positions, both immediately above the orbiter cargo bay and beyond. It can act in a primary docking role and, if required, can assist actively in the berthing process. From an analysis of ten reference missions, it was determined that two types of HPA mobility are needed; a tilt table, which simply swings out of the cargo bay, pivoting about an athwartships y axis, and an articulated arm. Illustration of the aid are provided.

  14. Orbital rhabdomyosarcomas: A review

    PubMed Central

    Jurdy, Lama; Merks, Johanus H.M.; Pieters, Bradly R.; Mourits, Maarten P.; Kloos, Roel J.H.M.; Strackee, Simone D.; Saeed, Peerooz

    2013-01-01

    Rhabdomyosarcoma (RMS) is a highly malignant tumor and is one of the few life-threatening diseases that present first to the ophthalmologist. It is the most common soft-tissue sarcoma of the head and neck in childhood with 10% of all cases occurring in the orbit. RMS has been reported from birth to the seventh decade, with the majority of cases presenting in early childhood. Survival has changed drastically over the years, from 30% in the 1960’s to 90% presently, with the advent of new diagnostic and therapeutic modalities. The purpose of this review is to provide a general overview of primary orbital RMS derived from a literature search of material published over the last 10 years, as well as to present two representative cases of patients that have been managed at our institute. PMID:24227982

  15. Mercury orbiter transport study

    NASA Technical Reports Server (NTRS)

    Friedlander, A. L.; Feingold, H.

    1977-01-01

    A data base and comparative performance analyses of alternative flight mode options for delivering a range of payload masses to Mercury orbit are provided. Launch opportunities over the period 1980-2000 are considered. Extensive data trades are developed for the ballistic flight mode option utilizing one or more swingbys of Venus. Advanced transport options studied include solar electric propulsion and solar sailing. Results show the significant performance tradeoffs among such key parameters as trip time, payload mass, propulsion system mass, orbit size, launch year sensitivity and relative cost-effectiveness. Handbook-type presentation formats, particularly in the case of ballistic mode data, provide planetary program planners with an easily used source of reference information essential in the preliminary steps of mission selection and planning.

  16. On-orbit coldwelding

    NASA Technical Reports Server (NTRS)

    Dursch, Harry; Spear, Steve

    1991-01-01

    Spacecraft mechanisms are required to operate in the space environment for extended periods of time. A significant concern to the spacecraft designer is the possibility of metal to metal coldwelding or significant increases in friction. Coldwelding can occur between atomically clean metal surfaces when carefully prepared in a vacuum chamber on earth. The question is whether coldwelding occurs in orbit service conditions. The results of the System Special Investigation Group's (SIG's) investigation into whether coldwelding had occurred on any Long Duration Exposure Facility (LDEF) hardware are presented. The results of a literature search into previous ground based anomalies is also presented. Results show that even though there have been no documented on-orbit coldwelding related failures, precautions should be taken to ensure that coldwelding does not occur in the space environment and that seizure does not occur in the prelaunch or launch environment.

  17. STS-125 Orbital Debris

    NASA Image and Video Library

    2009-07-02

    JSC2010-E-054445 (2 July 2009) --- Members of the Orbital Debris Program Office and the Hypervelocity Impact Technology Facility at JSC record images of impact craters and other surface data on the returned Wide Field and Planetary Camera (WFPC-2) of the Hubble Space Telescope. Inspection took place at the Goddard Space Flight Center during the summer of 2009. Photo credit: NASA or National Aeronautics and Space Administration

  18. Orbital Debris Modeling

    NASA Technical Reports Server (NTRS)

    Liou, J. C.

    2012-01-01

    Presentation outlne: (1) The NASA Orbital Debris (OD) Engineering Model -- A mathematical model capable of predicting OD impact risks for the ISS and other critical space assets (2) The NASA OD Evolutionary Model -- A physical model capable of predicting future debris environment based on user-specified scenarios (3) The NASA Standard Satellite Breakup Model -- A model describing the outcome of a satellite breakup (explosion or collision)

  19. Small Mercury Relativity Orbiter

    NASA Technical Reports Server (NTRS)

    Bender, Peter L.; Vincent, Mark A.

    1989-01-01

    The accuracy of solar system tests of gravitational theory could be very much improved by range and Doppler measurements to a Small Mercury Relativity Orbiter. A nearly circular orbit at roughly 2400 km altitude is assumed in order to minimize problems with orbit determination and thermal radiation from the surface. The spacecraft is spin-stabilized and has a 30 cm diameter de-spun antenna. With K-band and X-band ranging systems using a 50 MHz offset sidetone at K-band, a range accuracy of 3 cm appears to be realistically achievable. The estimated spacecraft mass is 50 kg. A consider-covariance analysis was performed to determine how well the Earth-Mercury distance as a function of time could be determined with such a Relativity Orbiter. The minimum data set is assumed to be 40 independent 8-hour arcs of tracking data at selected times during a two year period. The gravity field of Mercury up through degree and order 10 is solved for, along with the initial conditions for each arc and the Earth-Mercury distance at the center of each arc. The considered parameters include the gravity field parameters of degree 11 and 12 plus the tracking station coordinates, the tropospheric delay, and two parameters in a crude radiation pressure model. The conclusion is that the Earth-Mercury distance can be determined to 6 cm accuracy or better. From a modified worst-case analysis, this would lead to roughly 2 orders of magnitude improvement in the knowledge of the precession of perihelion, the relativistic time delay, and the possible change in the gravitational constant with time.

  20. Small Mercury Relativity Orbiter

    NASA Astrophysics Data System (ADS)

    Bender, Peter L.; Vincent, Mark A.

    1989-08-01

    The accuracy of solar system tests of gravitational theory could be very much improved by range and Doppler measurements to a Small Mercury Relativity Orbiter. A nearly circular orbit at roughly 2400 km altitude is assumed in order to minimize problems with orbit determination and thermal radiation from the surface. The spacecraft is spin-stabilized and has a 30 cm diameter de-spun antenna. With K-band and X-band ranging systems using a 50 MHz offset sidetone at K-band, a range accuracy of 3 cm appears to be realistically achievable. The estimated spacecraft mass is 50 kg. A consider-covariance analysis was performed to determine how well the Earth-Mercury distance as a function of time could be determined with such a Relativity Orbiter. The minimum data set is assumed to be 40 independent 8-hour arcs of tracking data at selected times during a two year period. The gravity field of Mercury up through degree and order 10 is solved for, along with the initial conditions for each arc and the Earth-Mercury distance at the center of each arc. The considered parameters include the gravity field parameters of degree 11 and 12 plus the tracking station coordinates, the tropospheric delay, and two parameters in a crude radiation pressure model. The conclusion is that the Earth-Mercury distance can be determined to 6 cm accuracy or better. From a modified worst-case analysis, this would lead to roughly 2 orders of magnitude improvement in the knowledge of the precession of perihelion, the relativistic time delay, and the possible change in the gravitational constant with time.

  1. Spectrophotovoltaic orbital power generation

    NASA Technical Reports Server (NTRS)

    Onffroy, J. R.

    1980-01-01

    The feasibilty of a spectrophotovoltaic orbital power generation system that optically concentrates solar energy is demonstrated. A dichroic beam-splitting mirror is used to divide the solar spectrum into two wavebands. Absorption of these wavebands by GaAs and Si solar cell arrays with matched energy bandgaps increases the cell efficiency while decreasing the amount of heat that must be rejected. The projected cost per peak watt if this system is $2.50/W sub p.

  2. 'Spider' in Earth Orbit

    NASA Technical Reports Server (NTRS)

    1969-01-01

    View of the Apollo 9 Lunar Module 'Spider' in a lunar landing configuration photographed by Command Module pilot David Scott inside the Command/Service Module 'Gumdrop' on the fifth day of the Apollo 9 earth-orbital mission. The landing gear on 'Spider' has been deployed. lunar surface probes (sensors) extend out from the landing gear foot pads. Inside the 'Spider' were astronauts James A. McDivitt, Apollo 9 Commander; and Russell L. Schweickart, Lunar Module pilot.

  3. Prospecting from Orbit

    NASA Image and Video Library

    2017-09-04

    The combination of morphological and topographic information from stereo images from NASA's Mars Reconnaissance Orbiter, as well as compositional data from near-infrared spectroscopy has been proven to be a powerful tool for understanding the geology of Mars. Beginning with the OMEGA instrument on the European Space Agency's Mars Express orbiter in 2003, the surface of Mars has been examined at near-infrared wavelengths by imaging spectrometers that are capable of detecting specific minerals and mapping their spatial extent. The CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) instrument on our orbiter is a visible/near-infrared imaging spectrometer, and the HiRISE camera works together with it to document the appearance of mineral deposits detected by this orbital prospecting. Mawrth Vallis is one of the regions on Mars that has attracted much attention because of the nature and diversity of the minerals identified by these spectrometers. It is a large, ancient outflow channel on the margin of the Southern highlands and Northern lowlands. Both the OMEGA and CRISM instruments have detected clay minerals here that must have been deposited in a water-rich environment, probably more than 4 billion years ago. For this reason, Mawrth Vallis is one of the two candidate landing sites for the future Mars Express Rover Mission planned by the European Space Agency. This image was targeted on a location where the CRISM instrument detected a specific mineral called alunite, KAl3(SO4)2(OH)6. Alunite is a hydrated aluminum potassium sulfate, a mineral that is notable because it must have been deposited in a wet acidic environment, rich in sulfuric acid. Our image shows that the deposit is bright and colorful, and extensively fractured. The width of the cutout is 1.2 kilometers. https://photojournal.jpl.nasa.gov/catalog/PIA21936

  4. Orbitals and orbital energies in DFT and TDDFT

    NASA Astrophysics Data System (ADS)

    Baerends, Evert Jan

    The status and meaning of orbitals and orbital energies in the Kohn-Sham one-electron model of DFT has been controversial, in contrast to Hartree-Fock orbitals and orbital energies. We will argue the opposite: the exact Kohn-Sham orbitals of DFT are ''better'' than HF orbitals and their orbital energies are much closer to ionization energies than HF orbital energies are. This follows from the relation between the KS potential and the wavefunction, which can be cast in the form vs =vc , kin +vH +vxchole +vresp, where each term depends on the KS orbitals and the wavefunction (the one- or two-particle density matrices). The response potential vresp (r) = ∑ j ∞|/dj(r) | 2 ρ (r) Ij - ∑ i H|/ψs , i(r) | 2 ρ (r) (-ɛi) (dj is the Dyson orbital corresponding to ion state ΨjN - 1 , ψs , i is a Kohn-Sham orbital) enables the connection between ionization energies Ii and orbital energies ɛi to be made. For virtual orbitals and orbital energies similar statements can be made: the shapes and energies of the (exact) KS orbitals are much more realistic than those of the Hartree-Fock model or hybrid functionals. The HOMO-LUMO gap in molecules is very close to the optical gap, and very different from the fundamental gap. In solids the situation is very different, which is the well-known ''KS gap problem''. Again the response potential vresp (a good approximation to it) helps to solve this problem, affording a straigtforward correction method of the KS gap to the fundamental gap.

  5. Plotting Orbital Trajectories For Maneuvers

    NASA Technical Reports Server (NTRS)

    Brody, Adam R.

    1991-01-01

    Interactive Orbital Trajectory Planning Tool (EIVAN) computer program is forward-looking interactive orbit-trajectory-plotting software tool for use with proximity operations (operations occurring within 1-km sphere of space station) and other maneuvers. Developed to plot resulting trajectories, to provide better comprehension of effects of orbital mechanics, and to help user develop heuristics for planning missions on orbit. Program runs with Microsoft's Excel for execution on MacIntosh computer running MacIntosh OS.

  6. Orbital shadowing for 3-flows

    NASA Astrophysics Data System (ADS)

    Gan, Shaobo; Li, Ming

    2017-05-01

    We call that a flow has the orbital shadowing property if for any ε > 0 there is d > 0 such that, for any d-pseudo orbit g (t) there exists an orbit Orb (x) satisfying distH (g (t) ‾ , Orb (x) ‾) < ε. In this paper, we show that the C1-interior of the set of 3-dimensional flows having the orbital shadowing property is contained in the set of Ω-stable 3-flows.

  7. Orbiter Autoland reliability analysis

    NASA Technical Reports Server (NTRS)

    Welch, D. Phillip

    1993-01-01

    The Space Shuttle Orbiter is the only space reentry vehicle in which the crew is seated upright. This position presents some physiological effects requiring countermeasures to prevent a crewmember from becoming incapacitated. This also introduces a potential need for automated vehicle landing capability. Autoland is a primary procedure that was identified as a requirement for landing following and extended duration orbiter mission. This report documents the results of the reliability analysis performed on the hardware required for an automated landing. A reliability block diagram was used to evaluate system reliability. The analysis considers the manual and automated landing modes currently available on the Orbiter. (Autoland is presently a backup system only.) Results of this study indicate a +/- 36 percent probability of successfully extending a nominal mission to 30 days. Enough variations were evaluated to verify that the reliability could be altered with missions planning and procedures. If the crew is modeled as being fully capable after 30 days, the probability of a successful manual landing is comparable to that of Autoland because much of the hardware is used for both manual and automated landing modes. The analysis indicates that the reliability for the manual mode is limited by the hardware and depends greatly on crew capability. Crew capability for a successful landing after 30 days has not been determined yet.

  8. Orbital spacecraft consumables resupply

    NASA Technical Reports Server (NTRS)

    Dominick, Sam M.; Eberhardt, Ralph N.; Tracey, Thomas R.

    1988-01-01

    The capability to replenish spacecraft, satellites, and laboratories on-orbit with consumable fluids provides significant increases in their cost and operational effectiveness. Tanker systems to perform on-orbit fluid resupply must be flexible enough to operate from the Space Transportation System (STS), Space Station, or the Orbital Maneuvering Vehicle (OMV), and to accommodate launch from both the Shuttle and Expendable Launch Vehicles (ELV's). Resupply systems for storable monopropellant hydrazine and bipropellants, and water have been developed. These studies have concluded that designing tankers capable of launch on both the Shuttle and ELV's was feasible and desirable. Design modifications and interfaces for an ELV launch of the tanker systems were identified. Additionally, it was determined that modularization of the tanker subsystems was necessary to provide the most versatile tanker and most efficient approach for use at the Space Station. The need to develop an automatic umbilical mating mechanism, capable of performing both docking and coupler mating functions was identified. Preliminary requirements for such a mechanism were defined. The study resulted in a modular tanker capable of resupplying monopropellants, bipropellants, and water with a single design.

  9. Laplacian Orbit Determination

    NASA Astrophysics Data System (ADS)

    Branham, R. L., Jr.

    2003-11-01

    Laplace's method is a standard for the calculation of a preliminary orbit. Certain modifications enhance its efficacy: reduce the observations, if necessary, by use of the L1 criterion; use a polynomial, whose order is determined by impersonal criteria, to calculate the first and second derivatives of observational quantities; combine the separate equations, one to determine the heliocentric distance of the object and the other its geocentric distance, into one polynomial equation for the heliocentric distance, whose roots are found by a standard algorithm; use recursion to calculate the f and g series. At least one differential correction is recommended to increase the accuracy of the computed orbital elements. Difficult problems, lack of convergence of the differential corrections, for example, can be handled by total least squares or ridge regression. The method is first applied to calculate a preliminary orbit of Comet P/ 1846 D1 (de Vico) from 59 observations made during five days in 1995 and then to a more difficult object, the Amor type minor planet 1982 DV (3288 Seleucus).

  10. An Orbit Plan toward AKATSUKI Venus Reencounter and Orbit Injection

    NASA Technical Reports Server (NTRS)

    Kawakatsu, Yasuhiro; Campagnola, Stefano; Hirose, Chikako; Ishii, Nobuaki

    2012-01-01

    On December 7, 2010, AKATSUKI, the Japanese Venus explorer reached its destination and tried to inject itself into Venus orbit. However, due to a malfunction of the propulsion system, the maneuver was interrupted and AKATSUKI again escaped out from the Venus into an interplanetary orbit. Telemetry data from AKATSUKI suggests the possibility to perform orbit maneuvers to reencounter the Venus and retry Venus orbit injection. Reported in this paper is an orbit plan investigated under this situation. The latest results reflecting the maneuvers conducted in the autumn 2011 is introduced as well.

  11. An Orbit Plan toward AKATSUKI Venus Reencounter and Orbit Injection

    NASA Technical Reports Server (NTRS)

    Kawakatsu, Yasuhiro; Campagnola, Stefano; Hirose, Chikako; Ishii, Nobuaki

    2012-01-01

    On December 7, 2010, AKATSUKI, the Japanese Venus explorer reached its destination and tried to inject itself into Venus orbit. However, due to a malfunction of the propulsion system, the maneuver was interrupted and AKATSUKI again escaped out from the Venus into an interplanetary orbit. Telemetry data from AKATSUKI suggests the possibility to perform orbit maneuvers to reencounter the Venus and retry Venus orbit injection. Reported in this paper is an orbit plan investigated under this situation. The latest results reflecting the maneuvers conducted in the autumn 2011 is introduced as well.

  12. Circular-Orbit Maintenance Strategies for Primitive Body Orbiters

    NASA Technical Reports Server (NTRS)

    Wallace, Mark S.; Broschart, Stephen

    2013-01-01

    For missions to smaller primitive bodies, solar radiation pressure (SRP) is a significant perturbation to Keplerian dynamics. For most orbits, SRP drives large oscillations in orbit eccentricity, which leads to large perturbations from the irregular gravity field at periapsis. Ultimately, chaotic motion results that often escapes or impacts that body. This paper presents an orbit maintenance strategy to keep the orbit eccentricity small, thus avoiding the destabilizing secondary interaction with the gravity field. An estimate of the frequency and magnitude of the required maneuvers as a function of the orbit and body parameters is derived from the analytic perturbation equations.

  13. Circular-Orbit Maintenance Strategies for Primitive Body Orbiters

    NASA Technical Reports Server (NTRS)

    Wallace, Mark S.; Broschart, Stephen

    2013-01-01

    For missions to smaller primitive bodies, solar radiation pressure (SRP) is a significant perturbation to Keplerian dynamics. For most orbits, SRP drives large oscillations in orbit eccentricity, which leads to large perturbations from the irregular gravity field at periapsis. Ultimately, chaotic motion results that often escapes or impacts that body. This paper presents an orbit maintenance strategy to keep the orbit eccentricity small, thus avoiding the destabilizing secondary interaction with the gravity field. An estimate of the frequency and magnitude of the required maneuvers as a function of the orbit and body parameters is derived from the analytic perturbation equations.

  14. Wobbly Planet Orbital Schematic Illustration

    NASA Image and Video Library

    2014-02-04

    This illustration shows the unusual orbit of planet Kepler-413b around a close pair of orange and red dwarf stars. The planet 66-day orbit is tilted 2.5 degrees with respect to the plane of the binary stars orbit.

  15. Orbiter KU-band transmitter

    NASA Technical Reports Server (NTRS)

    Halterman, R.

    1976-01-01

    The design, build, and test of an engineering breadboard Ku band quadraphase shift keyed and wideband frequency modulated transmitter are described. This orbiter Ku band transmitter drawer is to simulate the orbiter transmitter and meet the functional requirements of the orbiter communication link.

  16. Orbiter OMS and RCS technology

    NASA Technical Reports Server (NTRS)

    Boudreaux, R. A.

    1982-01-01

    Orbiter Orbital Maneuver Subsystem (OMS) and Reaction Control Subsystem (RCS) tankage has proved to be highly successful in shuttle flights on-orbit propellant transfer tests were done. Tank qualification tests along with flight demonstrations were carried out future uses of storable propellants are cited.

  17. Orbital phase design of diradicals.

    PubMed

    Ma, Jing; Inagaki, Satoshi; Wang, Yong

    2010-01-01

    Over the last three decades the rational design of diradicals has been a challenging issue because of their special features and activities in organic reactions and biological processes. The orbital phase theory has been developed for understanding the properties of diradicals and designing new candidates for synthesis. The orbital phase is an important factor in promoting the cyclic orbital interaction. When all of the conditions: (1) the electron-donating orbitals are out of phase; (2) the accepting orbitals are in phase; and (3) the donating and accepting orbitals are in phase, are simultaneously satisfied, the system is stabilized by the effective delocalization and polarization. Otherwise, the system is less stable. According to the orbital phase continuity requirement, we can predict the spin preference of π-conjugated diradicals and relative stabilities of constitutional isomers. Effects of the intramolecular interaction of bonds and unpaired electrons on the spin preference, thermodynamic and kinetic stabilities of the singlet and triplet states of localized 1,3-diradicals were also investigated by orbital phase theory. Taking advantage of the ring strains, several monocyclic and bicyclic systems were designed with appreciable singlet preference and kinetic stabilities. Substitution effects on the ground state spin and relative stabilities of diradicals were rationalized by orbital interactions without loss of generality. Orbital phase predictions were supported by available experimental observations and sophisticated calculation results. In comparison with other topological models, the orbital phase theory has some advantages. Orbital phase theory can provide a general model for both π-conjugated and localized diradicals. The relative stabilities and spin preference of all kinds of diradicals can be uniformly rationalized by the orbital phase property. The orbital phase theory is applied to the conformations of diradicals and the geometry

  18. Framboidal and idiomorphic pyrite in the upper Maastrichtian sedimentary rocks at Gabal Oweina, Nile Valley, Egypt: Formation processes, oxidation products and genetic implications to the origin of framboidal pyrite

    NASA Astrophysics Data System (ADS)

    Soliman, Mamdouh F.; El Goresy, Ahmed

    2012-08-01

    The upper Maastrichtian organic-rich sediments studied at Gabal Oweina, Egypt, are moderately enriched in syngenetic and diagenetic pyrite. Pyrite occurs mostly as layers or bands, group of lamina, lenses, diagenetic intercalated pockets, burrow fills and disseminated individual pyrite framboids and crystals within the host sediments. The pyritic thin bands and lamina consist mostly of unconsolidated to compact-oriented pyrite (oriented along the bedding planes) in gypsiferous-clayey matrix and less common as poorly oriented pyrite crystallites. In several cases, pyrite crystals of the latter type depict zoning, fracturing and micro-concretions. Pyritic burrow fills are composed mainly of pyrite, phosphatic ooids, microfossils, glauconitic grains, poorly graphitized carbon and native sulfur. Pyrite replaces minerals other than gypsum, sulfur or carbon. It also replaces microfossils thus turning some of the phosphatic ooids and microfossils to pyritized pseudomorphs. None of the studied phosphate ooids or framboids contains any mackinawite, pyrrhotite or greigite. Based on the microscopic and SEM observations of the micro-textures of disseminated pyrite found at Gabal Oweina section, four morphological forms of primary pyrite could be identified: (1) Grouped multiple-framboids; (2) Individual framboids; (3) Pyrite idiomorphic crystal overgrowths on framboids and (4) Single and aggregates of euhedral pyrite crystals. The multiple-framboid formation may have emerged from three successive processes: nucleation and growth of individual aggregates of the microcrystals to form combined micro-framboids (the growth of framboids); and followed by grouping of the several pyrite framboids. Direct pyrite nucleation (shell formation), crystallization, and aggregation processes might complete a single framboid. The disseminated single and aggregated euhedral pyrite crystals bear evidence indicating that their formation was via nucleation and growth of pyrite crystallites and

  19. Orbital maneuvers and space rendezvous

    NASA Astrophysics Data System (ADS)

    Butikov, Eugene I.

    2015-12-01

    Several possibilities of launching a space vehicle from the orbital station are considered and compared. Orbital maneuvers discussed in the paper can be useful in designing a trajectory for a specific space mission. The relative motion of orbiting bodies is investigated on examples of spacecraft rendezvous with the space station that stays in a circular orbit around the Earth. An elementary approach is illustrated by an accompanying simulation computer program and supported by a mathematical treatment based on fundamental laws of physics and conservation laws. Material is appropriate for engineers and other personnel involved in space exploration, undergraduate and graduate students studying classical physics and orbital mechanics.

  20. Radar Surveys of Meteoroid Orbits

    NASA Astrophysics Data System (ADS)

    Baggaley, W. J.

    1995-01-01

    Radar facilities providing routine measurements of the heliocentric orbits of meteoroids are valuable in providing a data-base of the orbital characteristics of the solar system small body population in the mass range about 10-2 down to 10-6 g. Such an orbital information background is essential for an understanding of the evolutionary processes of this component. An outline is presented of orbit-finding systems; their inherent limitations and associated selection effects with some emphasis given to the on-going southern hemisphere routine survey provided by the AMOR facility which provides orbits down to a limiting magnitude ˜ +13.

  1. Global Orbit Feedback in RHIC

    SciTech Connect

    Minty, M.; Hulsart, R.; Marusic, A.; Michnoff, R.; Ptitsyn, V.; Robert-Demolaize, G.; Satogata, T.

    2010-05-23

    For improved reproducibility of good operating conditions and ramp commissioning efficiency, new dual-plane slow orbit feedback during the energy ramp was implemented during run-10 in the Relativistic Heavy Ion Collider (RHIC). The orbit feedback is based on steering the measured orbit, after subtraction of the dispersive component, to either a design orbit or to a previously saved reference orbit. Using multiple correctors and beam position monitors, an SVD-based algorithm is used for determination of the applied corrections. The online model is used as a basis for matrix computations. In this report we describe the feedback design, review the changes made to realize its implementation, and assess system performance.

  2. Lunar Prospector Orbit Determination Results

    NASA Technical Reports Server (NTRS)

    Beckman, Mark; Concha, Marco

    1998-01-01

    The orbit support for Lunar Prospector (LP) consists of three main areas: (1) cislunar orbit determination, (2) rapid maneuver assessment using Doppler residuals, and (3) routine mapping orbit determination. The cislunar phase consisted of two trajectory correction maneuvers during the translunar cruise followed by three lunar orbit insertion burns. This paper will detail the cislunar orbit determination accuracy and the real-time assessment of the cislunar trajectory correction and lunar orbit insertion maneuvers. The non-spherical gravity model of the Moon is the primary influence on the mapping orbit determination accuracy. During the first two months of the mission, the GLGM-2 lunar potential model was used. After one month in the mapping orbit, a new potential model was developed that incorporated LP Doppler data. This paper will compare and contrast the mapping orbit determination accuracy using these two models. LP orbit support also includes a new enhancement - a web page to disseminate all definitive and predictive trajectory and mission planning information. The web site provides definitive mapping orbit ephemerides including moon latitude and longitude, and four week predictive products including: ephemeris, moon latitude/longitude, earth shadow, moon shadow, and ground station view periods. This paper will discuss the specifics of this web site.

  3. Viking orbiter attitude control analysis

    NASA Technical Reports Server (NTRS)

    Rodriguez, G.

    1977-01-01

    Two Viking orbiters are currently in Mars orbit. In the nearly two years since they were launched, the orbiters have successfully performed many functions including transportation of the Viking landers to Mars. The orbiters have for the last year provided relay links for lander-earth communications, and they have carried out from orbit their own scientific exploration of the planet. Crucial to the success of the orbiters has been the performance of the on-board attitude control system, which has provided the required orbiter stabilization and orientation throughout the missions. A comprehensive spacecraft and attitude control system dynamic analysis was necessary to certify the control system before launch and to evaluate its flight performance. This paper contains an outline of the analysis and of some of its results.

  4. Orbital Debris: A Policy Perspective

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas L.

    2007-01-01

    A viewgraph presentation describing orbital debris from a policy perspective is shown. The contents include: 1) Voyage through near-Earth Space-animation; 2) What is Orbital Debris?; 3) Orbital Debris Detectors and Damage Potential; 4) Hubble Space Telescope; 5) Mir Space Station Solar Array; 6) International Space Station; 7) Space Shuttle; 8) Satellite Explosions; 9) Satellite Collisions; 10) NASA Orbital Debris Mitigation Guidelines; 11) International Space Station Jettison Policy; 12) Controlled/Uncontrolled Satellite Reentries; 13) Return of Space Objects; 14) Orbital Debris and U.S. National Space Policy; 15) U.S Government Policy Strategy; 16) Bankruptcy of the Iridium Satellite System; 17) Inter-Agency Space Debris Coordination Committee (IADC); 18) Orbital Debris at the United Nations; 19) Chinese Anti-satellite System; 20) Future Evolution of Satellite Population; and 21) Challenge of Orbital Debris

  5. Hypervelocity Orbital Intercept Guidance

    DTIC Science & Technology

    1988-04-14

    Professor Charles E. Fosha, Jr. Terminal guidance of a hypervelocity exo-atmospheric orbital interceptor with free end-time is examined. The pursuer is...stochastic nonlinear systems with free end-time was developed by Tse and 29 Bar-Shalom [5]. This method differs from the optimal control formulation...Vol. AC-18, No. 2, April 1973, pp. 98-108. 5. Tse, E., and Y. Bar-Shalom, "Adaptive Dual Control For Stochastic Nonlinear Systems with Free End- Time

  6. Current orbital debris environment

    NASA Technical Reports Server (NTRS)

    Kessler, Donald J.

    1989-01-01

    NASA has instituted a plan for the definition of activities and resources required over the coming decade for the deepening of current understanding of anthropogenic orbital debris, and its effects on future mission operations. This understanding will be the basis of policy definition and policy implementation efforts. The most immediate requirement is the definition of the debris environment, with emphasis on data for debris sizes smaller than 4 cm. Systems-damage criteria and hypervelocity-impact theory will then be used to define the hazard to specific spacecraft.

  7. Orbiter door closure tools

    NASA Technical Reports Server (NTRS)

    Acres, W. R.

    1980-01-01

    Safe reentry of the shuttle orbiter requires that the payload bay doors be closed and securely latched. Since a malfunction in the door drive or bulkhead latch systems could make safe reentry impossible, the requirement to provide tools to manually close and secure the doors was implemented. The tools would disconnect a disabled door or latch closure system and close and secure the doors if the normal system failed. The tools required to perform these tasks have evolved into a set that consists of a tubing cutter, a winch, a latching tool, and a bolt extractor. The design, fabrication, and performance tests of each tool are described.

  8. Lunar Exploration Orbiter (LEO)

    NASA Astrophysics Data System (ADS)

    Jaumann, R.; Spohn, T.; Hiesinger, H.; Jessberger, E. K.; Neukum, G.; Oberst, J.; Helbert, J.; Christensen, U.; Keller, H. U.; Mall, U.; Böhnhardt, H.; Hartogh, P.; Glassmeier, K.-H.; Auster, H.-U.; Moreira, A.; Werner, M.; Pätzold, M.; Palme, H.; Wimmer-Schweingruber, R.; Mandea, M.; Lesur, V.; Häusler, B.; Hördt, A.; Eichentopf, K.; Hauber, E.; Hoffmann, H.; Köhler, U.; Kührt, E.; Michaelis, H.; Pauer, M.; Sohl, F.; Denk, T.; van Gasselt, S.

    2007-08-01

    The Moon is an integral part of the Earth-Moon system, it is a witness to more than 4.5 b. y. of solar system history, and it is the only planetary body except Earth for which we have samples from known locations. The Moon is our closest companion and can easily be reached from Earth at any time, even with a relatively modest financial budget. Consequently, the Moon was the first logical step in the exploration of our solar system before we pursued more distant targets such as Mars and beyond. The vast amount of knowledge gained from the Apollo and other lunar missions of the late 1960's and early 1970's demonstrates how valuable the Moon is for the understanding of our planetary system. Even today, the Moon remains an extremely interesting target scientifically and technologically, as ever since, new data have helped to address some of our questions about the Earth-Moon system, many questions remained. Therefore, returning to the Moon is the critical stepping-stone to further exploring our immediate planetary neighborhood. In this concept study, we present scientific and technological arguments for a national German lunar mission, the Lunar Explorations Orbiter (LEO). Numerous space-faring nations have realized and identified the unique opportunities related to lunar exploration and have planned missions to the Moon within the next few years. Among these missions, LEO will be unique, because it will globally explore the Moon in unprecedented spatial and spectral resolution. LEO will significantly improve our understanding of the lunar surface composition, surface ages, mineralogy, physical properties, interior, thermal history, gravity field, regolith structure, and magnetic field. The Lunar Explorations Orbiter will carry an entire suite of innovative, complementary technologies, including high-resolution camera systems, several spectrometers that cover previously unexplored parts of the electromagnetic spectrum over a broad range of wavelengths, microwave and

  9. Periodic orbits for three and four co-orbital bodies

    NASA Astrophysics Data System (ADS)

    Verrier, P. E.; McInnes, C. R.

    2014-08-01

    We investigate the natural families of periodic orbits associated with the equilibrium configurations of the planar-restricted 1 + n-body problem for the case 2 ≤ n ≤ 4 equal-mass satellites. Such periodic orbits can be used to model both trojan exoplanetary systems and parking orbits for captured asteroids within the Solar system. For n = 2, there are two families of periodic orbits associated with the equilibria of the system: the well-known horseshoe and tadpole orbits. For n = 3, there are three families that emanate from the equilibrium configurations of the satellites, while for n = 4, there are six such families as well as numerous additional connecting families. The families of periodic orbits are all of the horseshoe or tadpole type, and several have regions of neutral linear stability.

  10. Resonant and secular orbital interactions

    NASA Astrophysics Data System (ADS)

    Zhang, Ke

    In stable solar systems, planets remain in nearly elliptical orbits around their stars. Over longer timescales, however, their orbital shapes and sizes change due to mutual gravitational perturbations. Orbits of satellites around a planet vary for the same reason. Because of their interactions, the orbits of planets and satellites today are different from what they were earlier. In order to determine their original orbits, which are critical constraints on formation theories, it is crucial to understand how orbits evolve over the age of the Solar System. Depending on their timescale, we classify orbital interactions as either short-term (orbital resonances) or long-term (secular evolution). My work involves examples of both interaction types. Resonant history of the small Neptunian satellites. In satellite systems, tidal migration brings satellite orbits in and out of resonances. During a resonance passage, satellite orbits change dramatically in a very short period of time. We investigate the resonant history of the six small Neptunian moons. In this unique system, the exotic orbit of the large captured Triton (with a circular, retrograde, and highly tilted orbit) influences the resonances among the small satellites very strongly. We derive an analytical framework which can be applied to Neptune's satellites and to similar systems. Our numerical simulations explain the current orbital tilts of the small satellites as well as constrain key physical parameters of both Neptune and its moons. Secular orbital interactions during eccentricity damping. Long-term periodic changes of orbital shape and orientation occur when two or more planets orbit the same star. The variations of orbital elements are superpositions of the same number of fundamental modes as the number of planets in the system. We investigate how this effect interacts with other perturbations imposed by external disturbances, such as the tides and relativistic effects. Through analytical studies of a

  11. Smartphone Photos From Orbit

    NASA Image and Video Library

    2017-09-28

    These images of Earth were reconstructed from photos taken by three smartphones in orbit, or "PhoneSats." The trio of PhoneSats launched on April 21, 2013, aboard the Antares rocket from NASA's Wallops Flight Facility and ended a successful mission on April 27. The ultimate goal of the PhoneSat mission was to determine whether a consumer-grade smartphone can be used as the main flight avionics for a satellite in space. During their time in orbit, the three miniature satellites used their smartphone cameras to take pictures of Earth and transmitted these "image-data packets" to multiple ground stations. Every packet held a small piece of the big picture. As the data became available, the PhoneSat Team and multiple amateur radio operators around the world collaborated to piece together photographs from the tiny data packets. Read more: 1.usa.gov/ZsWnQG Credit: NASA/Ames NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  12. Orbital debris issues

    NASA Astrophysics Data System (ADS)

    Kessler, D. J.

    Orbital debris issues fall into three major topics: Environment Definition, Spacecraft Hazard, and Space Object Management. The major issue under Environment Definition is defining the debris flux for sizes smaller (10 cm in diameter) than those tracked by the North American Aerospace Defense Command (NORAD). Sources for this size debris are fragmentation of larger objects, either by explosion or collision, and solid rocket motor products. Modeling of these sources can predict fluxes in low Earth orbit which are greater than the meteoroid environment. Techniques to measure the environment in the size interval between 1 mm and 10 cm are being developed, including the use of telescopes and radar both on the ground and in space. Some impact sensors designed to detect meteoroids may have detected solid rocket motor products. Once the environment is defined, it can be combined with hypervelocity impact data and damage criteria to evaluate the Spacecraft Hazard. Shielding may be required to obtain an acceptable damage level. Space Object Management includes techniques to control the environment and the desired policy to effectively minimize the hazard to spacecraft. One control technique - reducing the likelihood of future explosions in space - has already been implemented by NASA. The effectiveness of other techniques has yet to be evaluated.

  13. Orbital construction demonstration study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A conceptual design and program plan for an Orbital Construction Demonstration Article (OCDA) was developed that can be used for evaluating and establishing practical large structural assembly operations. A flight plan for initial placement and continued utility is presented as a basic for an entirely new shuttle payload line-item having great future potential benefit for space applications. The OCDA is a three-axis stabilized platform in low-earth orbit with many structural nodals for mounting large construction and fabrication equipments. This equipment would be used to explore methods for constructing the large structures for future missions. The OCDA would be supported at regular intervals by the shuttle. Construction experiments and consumables resupply are performed during shuttle visit periods. A 250 kw solar array provides sufficient power to support the shuttle while attached to the OCDA and to run construction experiments at the same time. Wide band communications with a Telemetry and Data Relay Satellite compatible high gain antenna can be used between shuttle revisits to perform remote controlled, TV assisted construction experiments.

  14. [Endoscopic approaches to the orbit].

    PubMed

    Cebula, H; Lahlou, A; De Battista, J C; Debry, C; Froelich, S

    2010-01-01

    During the last decade, the use of endoscopic endonasal approaches to the pituitary has increased considerably. The endoscopic endonasal and transantral approaches offer a minimally invasive alternative to the classic transcranial or transconjunctival approaches to the medial aspect of the orbit. The medial wall of the orbit, the orbital apex, and the optic canal can be exposed through a middle meatal antrostomy, an anterior and posterior ethmoidectomy, and a sphenoidotomy. The inferomedial wall of the orbit can be also perfectly visualized through a sublabial antrostomy or an inferior meatal antrostomy. Several reports have described the use of an endoscopic approach for the resection or the biopsy of lesions located on the medial extraconal aspect of the orbit and orbital apex. However, the resection of intraconal lesions is still limited by inadequate instrumentation. Other indications for the endoscopic approach to the orbit are the decompression of the orbit for Graves' ophthalmopathy and traumatic optic neuropathy. However, the optimal management of traumatic optic neuropathy remains very controversial. Endoscopic endonasal decompression of the optic nerve in case of tumor compression could be a more valid indication in combination with radiation therapy. Finally, the endoscopic transantral treatment of blowout fracture of the floor of the orbit is an interesting option that avoids the eyelid or conjunctive incision of traditional approaches. The collaboration between the neurosurgeon and the ENT surgeon is mandatory and reduces the morbidity of the approach. Progress in instrumentation and optical devices will certainly make this approach promising for intraconal tumor of the orbit.

  15. Optimal Continuous Thrust Orbital Evasive Maneuvers from Geosynchronous Orbit

    DTIC Science & Technology

    1986-12-01

    control thrusters, if its warning time and orbital parameters were appropriate. A model is developed using optimal control theory and is solved numericaly...Maneuvers of a Spacecraft Relative to a Point in Circular Orbit ,’ Journal of Guidance, Control . and Dynamics. 9(l): 27-31 (January -February 1966). 10... Elliptical Orbit ," Joursal of Guidance. Control . and Drjsmakjs1 (4: 271-275 (July- August 1979). 22. Meirovitch, Leonard. Methods of Anakytical Dynamics

  16. Orbital Evolution and Impact Hazard of Asteroids on Retrograde Orbits

    NASA Astrophysics Data System (ADS)

    Kankiewicz, P.; Włodarczyk, I.

    2014-07-01

    We present the past evolutional scenarios of known group of asteroids in retrograde orbits. Applying the latest observational data, we determined their nominal and averaged orbital elements. Next, we studied the behaviour of their orbital motion 1~My in the past (100~My in the future for two NEAs) taking into account the limitations of observational errors. It has been shown that the influence of outer planets perturbations in many cases can import small bodies on high inclination or retrograde orbits into the inner Solar System.

  17. General view of the Orbiter Discovery in the Orbiter Processing ...

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

    General view of the Orbiter Discovery in the Orbiter Processing Facility at Kennedy Space Center showing the payload bay doors open exposing the heat-dissipating radiator panels located on the inside of the payload bay doors. Also in the view is the boom portion of the boom sensor system deployed as part of the return to flight procedures after STS-107 to inspect the orbiter's thermal protection system. The Remote Manipulator System, the "Canadarm", and the airlock are seen in the background of the image. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  18. The orbit properties of colliding co-orbiting bodies

    NASA Technical Reports Server (NTRS)

    Freeman, John W.

    1987-01-01

    It is generally assumed that an ensemble of small bodies located in similar Keplarian orbits will, because of collisions, tend to disperse into more and more dissimilar orbits. This theory was challenged. Alfven maintains that for the case where the time between collisions is longer than the orbit period and the collisions are essentially inelastic the orbits and velocities will become more similar. This gives rise to the concepts of negative diffusion and jet streams. It is proposed that this question might be investigated experimentally using the space station. The proposed experiment is briefly described.

  19. Adaptive interplanetary orbit determination

    NASA Astrophysics Data System (ADS)

    Crain, Timothy Price

    This work documents the development of a real-time interplanetary orbit determination monitoring algorithm for detecting and identifying changes in the spacecraft dynamic and measurement environments. The algorithm may either be utilized in a stand-alone fashion as a spacecraft monitor and hypothesis tester by navigators or may serve as a component in an autonomous adaptive orbit determination architecture. In either application, the monitoring algorithm serves to identify the orbit determination filter parameters to be modified by an offline process to restore the operational model accuracy when the spacecraft environment changes unexpectedly. The monitoring algorithm utilizes a hierarchical mixture-of-experts to regulate a multilevel bank organization of extended Kalman filters. Banks of filters operate on the hierarchy top-level and are composed of filters with configurations representative of a specific environment change called a macromode. Fine differences, or micromodes, within the macromodes are represented by individual filter configurations. Regulation is provided by two levels of single-layer neural networks called gating networks. A single top-level gating network regulates the weighting among macromodes and each bank uses a gating network to regulate member filters internally. Experiments are conducted on the Mars Pathfinder cruise trajectory environment using range and Doppler data from the Deep Space Network. The experiments investigate the ability of the hierarchical mixture-of-experts to identify three environment macromodes: (1) unmodeled impulsive maneuvers, (2) changes in the solar radiation pressure dynamics, and (3) changes in the measurement noise strength. Two methods of initializing the gating networks are examined in each experiment. One method gives the neurons associated with all filters equivalent synaptic weight. The other method places greater weight on the operational filter initially believed to model the spacecraft environment. The

  20. 'Columbia Hills' from Orbit

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This view of the 'Columbia Hills' in Gusev Crater was made by draping an image from the Mars Orbiter Camera on NASA's Mars Global Surveyor orbiter (image E0300012 from that camera) over a digital elevation model that was derived from two Mars Orbiter Camera images (E0300012 and R0200357).

    This unique view is helpful to the rover team members as they plan the journey of NASA's Mars Exploration Rover Spirit to the base of the Columbia Hills and beyond. Spirit successfully completed a three-month primary mission, and so far remains healthy in an extended mission of bonus exploration. As of sol 135 (on May 21, 2004), Spirit sits approximately 680 meters (0.4 miles) away from its first target at the western base of the hills, a spot informally called 'West Spur.' The team estimates that Spirit will reach West Spur by sol 146 (June 1, 2004). Spirit will most likely remain there for about a week to study the outcrops and rocks associated with this location.

    When done there, Spirit will head approximately 620 meters (0.38 miles) to a higher-elevation location informally called 'Lookout Point.' Spirit might reach Lookout Point by around sol 165 (June 20, 2004). On the way, the rover will pass by and study ripple-shaped wind deposits that may reveal more information about wind processes on Mars.

    Lookout Point will provide a great vantage point for scientists to remotely study the inner basin area of the Columbia Hills. This basin contains a broad range of interesting geological targets including the informally named 'Home Plate' and other possible layered outcrops. These features suggest that the hills contain rock layers. Spirit might investigate the layers to determine whether they are water-deposited sedimentary rock.

    Once at Lookout Point, Spirit will acquire 360-degree panoramic images of the entire area to help define the rover's next steps. Assuming the rover stays healthy, Spirit will eventually drive down into the basin to get an up

  1. Orbital State Uncertainty Realism

    NASA Astrophysics Data System (ADS)

    Horwood, J.; Poore, A. B.

    2012-09-01

    Fundamental to the success of the space situational awareness (SSA) mission is the rigorous inclusion of uncertainty in the space surveillance network. The *proper characterization of uncertainty* in the orbital state of a space object is a common requirement to many SSA functions including tracking and data association, resolution of uncorrelated tracks (UCTs), conjunction analysis and probability of collision, sensor resource management, and anomaly detection. While tracking environments, such as air and missile defense, make extensive use of Gaussian and local linearity assumptions within algorithms for uncertainty management, space surveillance is inherently different due to long time gaps between updates, high misdetection rates, nonlinear and non-conservative dynamics, and non-Gaussian phenomena. The latter implies that "covariance realism" is not always sufficient. SSA also requires "uncertainty realism"; the proper characterization of both the state and covariance and all non-zero higher-order cumulants. In other words, a proper characterization of a space object's full state *probability density function (PDF)* is required. In order to provide a more statistically rigorous treatment of uncertainty in the space surveillance tracking environment and to better support the aforementioned SSA functions, a new class of multivariate PDFs are formulated which more accurately characterize the uncertainty of a space object's state or orbit. The new distribution contains a parameter set controlling the higher-order cumulants which gives the level sets a distinctive "banana" or "boomerang" shape and degenerates to a Gaussian in a suitable limit. Using the new class of PDFs within the general Bayesian nonlinear filter, the resulting filter prediction step (i.e., uncertainty propagation) is shown to have the *same computational cost as the traditional unscented Kalman filter* with the former able to maintain a proper characterization of the uncertainty for up to *ten

  2. 'Columbia Hills' from Orbit

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This view of the 'Columbia Hills' in Gusev Crater was made by draping an image from the Mars Orbiter Camera on NASA's Mars Global Surveyor orbiter (image E0300012 from that camera) over a digital elevation model that was derived from two Mars Orbiter Camera images (E0300012 and R0200357).

    This unique view is helpful to the rover team members as they plan the journey of NASA's Mars Exploration Rover Spirit to the base of the Columbia Hills and beyond. Spirit successfully completed a three-month primary mission, and so far remains healthy in an extended mission of bonus exploration. As of sol 135 (on May 21, 2004), Spirit sits approximately 680 meters (0.4 miles) away from its first target at the western base of the hills, a spot informally called 'West Spur.' The team estimates that Spirit will reach West Spur by sol 146 (June 1, 2004). Spirit will most likely remain there for about a week to study the outcrops and rocks associated with this location.

    When done there, Spirit will head approximately 620 meters (0.38 miles) to a higher-elevation location informally called 'Lookout Point.' Spirit might reach Lookout Point by around sol 165 (June 20, 2004). On the way, the rover will pass by and study ripple-shaped wind deposits that may reveal more information about wind processes on Mars.

    Lookout Point will provide a great vantage point for scientists to remotely study the inner basin area of the Columbia Hills. This basin contains a broad range of interesting geological targets including the informally named 'Home Plate' and other possible layered outcrops. These features suggest that the hills contain rock layers. Spirit might investigate the layers to determine whether they are water-deposited sedimentary rock.

    Once at Lookout Point, Spirit will acquire 360-degree panoramic images of the entire area to help define the rover's next steps. Assuming the rover stays healthy, Spirit will eventually drive down into the basin to get an up

  3. Precise Orbit Determination for ALOS

    NASA Technical Reports Server (NTRS)

    Nakamura, Ryo; Nakamura, Shinichi; Kudo, Nobuo; Katagiri, Seiji

    2007-01-01

    The Advanced Land Observing Satellite (ALOS) has been developed to contribute to the fields of mapping, precise regional land coverage observation, disaster monitoring, and resource surveying. Because the mounted sensors need high geometrical accuracy, precise orbit determination for ALOS is essential for satisfying the mission objectives. So ALOS mounts a GPS receiver and a Laser Reflector (LR) for Satellite Laser Ranging (SLR). This paper deals with the precise orbit determination experiments for ALOS using Global and High Accuracy Trajectory determination System (GUTS) and the evaluation of the orbit determination accuracy by SLR data. The results show that, even though the GPS receiver loses lock of GPS signals more frequently than expected, GPS-based orbit is consistent with SLR-based orbit. And considering the 1 sigma error, orbit determination accuracy of a few decimeters (peak-to-peak) was achieved.

  4. Energy Ordering of Molecular Orbitals

    PubMed Central

    2016-01-01

    Orbitals are invaluable in providing a model of bonding in molecules or between molecules and surfaces. Most present-day methods in computational chemistry begin by calculating the molecular orbitals of the system. To what extent have these mathematical objects analogues in the real world? To shed light on this intriguing question, we employ a photoemission tomography study on monolayers of 3,4,9,10-perylene-tetracarboxylic acid dianhydride (PTCDA) grown on three Ag surfaces. The characteristic photoelectron angular distribution enables us to assign individual molecular orbitals to the emission features. When comparing the resulting energy positions to density functional calculations, we observe deviations in the energy ordering. By performing complete active space calculations (CASSCF), we can explain the experimentally observed orbital ordering, suggesting the importance of static electron correlation beyond a (semi)local approximation. On the other hand, our results also show reality and robustness of the orbital concept, thereby making molecular orbitals accessible to experimental observations. PMID:27935313

  5. Calculating Trajectories And Orbits

    NASA Technical Reports Server (NTRS)

    Alderson, Daniel J.; Brady, Franklyn H.; Breckheimer, Peter J.; Campbell, James K.; Christensen, Carl S.; Collier, James B.; Ekelund, John E.; Ellis, Jordan; Goltz, Gene L.; Hintz, Gerarld R.; Legerton, Victor N.; Mccreary, Faith A.; Mitchell, Robert T.; Mottinger, Neil A.; Moultrie, Benjamin A.; Moyer, Theodore D.; Rinker, Sheryl L.; Ryne, Mark S.; Stavert, L. Robert; Sunseri, Richard F.

    1989-01-01

    Double-Precision Trajectory Analysis Program, DPTRAJ, and Orbit Determination Program, ODP, developed and improved over years to provide highly reliable and accurate navigation capability for deep-space missions like Voyager. Each collection of programs working together to provide desired computational results. DPTRAJ, ODP, and supporting utility programs capable of handling massive amounts of data and performing various numerical calculations required for solving navigation problems associated with planetary fly-by and lander missions. Used extensively in support of NASA's Voyager project. DPTRAJ-ODP available in two machine versions. UNIVAC version, NPO-15586, written in FORTRAN V, SFTRAN, and ASSEMBLER. VAX/VMS version, NPO-17201, written in FORTRAN V, SFTRAN, PL/1 and ASSEMBLER.

  6. Skylab Orbiter Workshop Illustration

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This cutaway illustration shows the characteristics and basic elements of the Skylab Orbiter Workshop (OWS). The OWS was divided into two major compartments. The lower level provided crew accommodations for sleeping, food preparation and consumption, hygiene, waste processing and disposal, and performance of certain experiments. The upper level consisted of a large work area and housed water storage tanks, a food freezer, storage vaults for film, scientific airlocks, mobility and stability experiment equipment, and other experimental equipment. The compartment below the crew quarters was a container for liquid and solid waste and trash accumulated throughout the mission. A solar array, consisting of two wings covered on one side with solar cells, was mounted outside the workshop to generate electrical power to augment the power generated by another solar array mounted on the solar observatory. Thrusters were provided at one end of the workshop for short-term control of the attitude of the space station.

  7. Orbiting Carbon Observatory

    NASA Technical Reports Server (NTRS)

    Miller, Charles E.

    2005-01-01

    Human impact on the environment has produced measurable changes in the geological record since the late 1700s. Anthropogenic emissions of CO2 today may cause the global climate to depart for its natural behavior for many millenia. CO2 is the primary anthropogenic driver of climate change. The Orbiting Carbon Observatory goals are to help collect measurements of atmospheric CO2, answering questions such as why the atmospheric CO2 buildup varies annually, the roles of the oceans and land ecosystems in absorbing CO2, the roles of North American and Eurasian sinks and how these carbon sinks respond to climate change. The present carbon cycle, CO2 variability, and climate uncertainties due atmospheric CO2 uncertainties are highlighted in this presentation.

  8. Orbital science's 'Bermuda Triangle'

    NASA Astrophysics Data System (ADS)

    Sherrill, Thomas J.

    1991-02-01

    The effects of a part of the inner Van Allen belt lying closest to the earth, known as the South Atlantic Anomaly (SAA) upon spacecraft including the Hubble Space Telescope (HST), are discussed. The area consists of positively charged ions and electrons from the Van Allen Belt which become trapped in the earth's dipole field. Contor maps representing the number of protons per square centimeter per second having energies greater than 10 million electron volts are presented. It is noted that the HST orbit causes it to spend about 15 percent of its time in the SAA, but that, unlike the experience with earlier spacecraft, the satellite's skin, internal structure, and normal electronic's packaging provides sufficient protection against eletrons, although some higher energy protons still get through. Various charged particle effects which can arise within scientific instruments including fluorescence, Cerenkov radiation, and induced radioactivity are described.

  9. Theory of Orbits

    NASA Astrophysics Data System (ADS)

    Boccaletti, Dino; Pucacco, Giuseppe

    This textbook treats Celestial Mechanics as well as Stellar Dynamics from the common point of view of orbit theory making use of the concepts and techniques from modern geometric mechanics. It starts with elementary Newtonian Mechanics and ends with the dynamics of chaotic motions. The book is meant for students in astronomy and physics alike. Prerequisite is a physicist's knowledge of calculus and differential geometry. Volume 1 begins with classical mechanics and a thorough treatment of the 2-body problem, including regularization, followed by an introduction to the N-body problem with particular attention given to the virial theorem. Then the authors discuss all important non-perturbative aspects of the 3-body problem. A final chapter deals with integrability of Hamilton-Jacobi-systems.

  10. Geology orbiter comparison study

    NASA Technical Reports Server (NTRS)

    Cutts, J. A. J.; Blasius, K. R.; Davis, D. R.; Pang, K. D.; Shreve, D. C.

    1977-01-01

    Instrument requirements of planetary geology orbiters were examined with the objective of determining the feasibility of applying standard instrument designs to a host of terrestrial targets. Within the basic discipline area of geochemistry, gamma-ray, X-ray fluorescence, and atomic spectroscopy remote sensing techniques were considered. Within the discipline area of geophysics, the complementary techniques of gravimetry and radar were studied. Experiments using these techniques were analyzed for comparison at the Moon, Mercury, Mars and the Galilean satellites. On the basis of these comparative assessments, the adaptability of each sensing technique was judged as a basic technique for many targets, as a single instrument applied to many targets, as a single instrument used in different mission modes, and as an instrument capability for nongeoscience objectives.

  11. Calculating Trajectories And Orbits

    NASA Technical Reports Server (NTRS)

    Alderson, Daniel J.; Brady, Franklyn H.; Breckheimer, Peter J.; Campbell, James K.; Christensen, Carl S.; Collier, James B.; Ekelund, John E.; Ellis, Jordan; Goltz, Gene L.; Hintz, Gerarld R.; hide

    1989-01-01

    Double-Precision Trajectory Analysis Program, DPTRAJ, and Orbit Determination Program, ODP, developed and improved over years to provide highly reliable and accurate navigation capability for deep-space missions like Voyager. Each collection of programs working together to provide desired computational results. DPTRAJ, ODP, and supporting utility programs capable of handling massive amounts of data and performing various numerical calculations required for solving navigation problems associated with planetary fly-by and lander missions. Used extensively in support of NASA's Voyager project. DPTRAJ-ODP available in two machine versions. UNIVAC version, NPO-15586, written in FORTRAN V, SFTRAN, and ASSEMBLER. VAX/VMS version, NPO-17201, written in FORTRAN V, SFTRAN, PL/1 and ASSEMBLER.

  12. TOPEX orbital radiation study

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Barth, J. M.

    1984-01-01

    The space radiation environment of the TOPEX spacecraft is investigated. A single trajectory was considered. The external (surface incident) charged particle radiation, predicted for the satellite, is determined by orbital flux integration for the specified trajectory. The latest standard models of the environment are used in the calculations. The evaluation is performed for solar maximum conditions. The spacecraft exposure to cosmic rays of galactic origin is evaluated over its flight path through the magnetosphere in terms of geomagnetic shielding effects, both for surface incident heavy ions and for particles emerging behind different material thickness. Limited shielding and dose evaluations are performed for simple infinite slab and spherical geometries. Results, given in graphical and tabular form, are analyzed, explained, and discussed. Conclusions are presented and commented on.

  13. Magellan Orbit Artist Concept

    NASA Image and Video Library

    1990-08-10

    An artist's concept of the Magellan spacecraft making a radar map of Venus. Magellan mapped 98 percent of Venus' surface at a resolution of 100 to 150 meters (about the length of a football or soccer field), using synthetic aperture radar, a technique that simulates the use of a much larger radar antenna. It found that 85 percent of the surface is covered with volcanic flows and showed evidence of tectonic movement, turbulent surface winds, lava channels and pancake-shaped domes. Magellan also produced high-resolution gravity data for 95 percent of the planet and tested a new maneuvering technique called aerobraking, using atmospheric drag to adjust its orbit. The spacecraft was commanded to plunge into Venus' atmosphere in 1994 as part of a final experiment to gather atmospheric data. http://photojournal.jpl.nasa.gov/catalog/PIA18175

  14. Orbital angular momentum microlaser

    NASA Astrophysics Data System (ADS)

    Miao, Pei; Zhang, Zhifeng; Sun, Jingbo; Walasik, Wiktor; Longhi, Stefano; Litchinitser, Natalia M.; Feng, Liang

    2016-07-01

    Structured light provides an additional degree of freedom for modern optics and practical applications. The effective generation of orbital angular momentum (OAM) lasing, especially at a micro- and nanoscale, could address the growing demand for information capacity. By exploiting the emerging non-Hermitian photonics design at an exceptional point, we demonstrate a microring laser producing a single-mode OAM vortex lasing with the ability to precisely define the topological charge of the OAM mode. The polarization associated with OAM lasing can be further manipulated on demand, creating a radially polarized vortex emission. Our OAM microlaser could find applications in the next generation of integrated optoelectronic devices for optical communications in both quantum and classical regimes.

  15. Orbital angular momentum microlaser.

    PubMed

    Miao, Pei; Zhang, Zhifeng; Sun, Jingbo; Walasik, Wiktor; Longhi, Stefano; Litchinitser, Natalia M; Feng, Liang

    2016-07-29

    Structured light provides an additional degree of freedom for modern optics and practical applications. The effective generation of orbital angular momentum (OAM) lasing, especially at a micro- and nanoscale, could address the growing demand for information capacity. By exploiting the emerging non-Hermitian photonics design at an exceptional point, we demonstrate a microring laser producing a single-mode OAM vortex lasing with the ability to precisely define the topological charge of the OAM mode. The polarization associated with OAM lasing can be further manipulated on demand, creating a radially polarized vortex emission. Our OAM microlaser could find applications in the next generation of integrated optoelectronic devices for optical communications in both quantum and classical regimes. Copyright © 2016, American Association for the Advancement of Science.

  16. Orbital Eccrine Hidrocystoma

    PubMed Central

    Marangoz, Deniz; Doğan Ekici, Işın; Çiftçi, Ferda

    2016-01-01

    A 29-year-old female patient presented with a painless mass on her upper eyelid medially. She noticed the mass 4 years earlier and it had increased in size over time. She had no diplopia, eyelid swelling, skin lesion overlying the mass, or visual disturbances. On ocular examination, eye movements and funduscopy were normal. The mass was movable and painless with palpation. Magnetic resonance imaging with contrast showed a 12x8x7 mm well-circumscribed cystic lesion with no contrast dye appearance. Surgical removal was performed delicately and no capsular rupture occured. Pathological examination revealed an eccrine hidrocystoma. Our aim is to underline that eccrine hidrocystoma should be included in differential diagnosis of orbital masses. PMID:28058171

  17. Exploratory orbit analysis

    SciTech Connect

    Michelotti, L.

    1989-03-01

    Unlike the other documents in these proceedings, this paper is neither a scientific nor a technical report. It is, rather, a short personal essay which attempts to describe an Exploratory Orbit Analysis (EOA) environment. Analyzing the behavior of a four or six dimensional nonlinear dynamical system is at least as difficult as analyzing events in high-energy collisions; the consequences of doing it badly, or slowly, would be at least as devastating; and yet the level of effort and expenditure invested in the latter, the very attention paid to it by physicists at large, must be two orders of magnitude greater than that given to the former. It is difficult to choose the model which best explains the behavior of a physical device if one does not first understand the behavior of the available models. The time is ripe for the development of a functioning EOA environment, which I will try to describe in this paper to help us achieve this goal.

  18. Orbit Determination Toolbox

    NASA Technical Reports Server (NTRS)

    Carpenter, James R.; Berry, Kevin; Gregpru. Late; Speckman, Keith; Hur-Diaz, Sun; Surka, Derek; Gaylor, Dave

    2010-01-01

    The Orbit Determination Toolbox is an orbit determination (OD) analysis tool based on MATLAB and Java that provides a flexible way to do early mission analysis. The toolbox is primarily intended for advanced mission analysis such as might be performed in concept exploration, proposal, early design phase, or rapid design center environments. The emphasis is on flexibility, but it has enough fidelity to produce credible results. Insight into all flight dynamics source code is provided. MATLAB is the primary user interface and is used for piecing together measurement and dynamic models. The Java Astrodynamics Toolbox is used as an engine for things that might be slow or inefficient in MATLAB, such as high-fidelity trajectory propagation, lunar and planetary ephemeris look-ups, precession, nutation, polar motion calculations, ephemeris file parsing, and the like. The primary analysis functions are sequential filter/smoother and batch least-squares commands that incorporate Monte-Carlo data simulation, linear covariance analysis, measurement processing, and plotting capabilities at the generic level. These functions have a user interface that is based on that of the MATLAB ODE suite. To perform a specific analysis, users write MATLAB functions that implement truth and design system models. The user provides his or her models as inputs to the filter commands. The software provides a capability to publish and subscribe to a software bus that is compliant with the NASA Goddard Mission Services Evolution Center (GMSEC) standards, to exchange data with other flight dynamics tools to simplify the flight dynamics design cycle. Using the publish and subscribe approach allows for analysts in a rapid design center environment to seamlessly incorporate changes in spacecraft and mission design into navigation analysis and vice versa.

  19. Orbiter utilization as an ACRV

    NASA Technical Reports Server (NTRS)

    Cruz, Jonathan N.; Heck, Michael L.; Kumar, Renjith R.; Mazanek, Daniel D.; Troutman, Patrick A.

    1990-01-01

    Assuming that a Shuttle Orbiter could be qualified to serve long duration missions attached to Space Station Freedom in the capacity as an Assured Crew Return Vehicle (ACRV), a study was conducted to identify and examine candidate attach locations. Baseline, modified hardware, and new hardware design configurations were considered. Dual simultaneous Orbiter docking accommodation were required. Resulting flight characteristics analyzed included torque equilibrium attitude (TEA), microgravity environment, attitude controllability, and reboost fuel requirements. The baseline Station could not accommodate two Orbiters. Modified hardware configurations analyzed had large TEA's. The utilization of an oblique docking mechanism best accommodated an Orbiter as an ACRV.

  20. Orbiter Servicer Rendezvous Simulation (ORSIM)

    NASA Astrophysics Data System (ADS)

    Amato, Amiel; Hoffman, Mickie D.

    Orbiter Servicer Rendezvous Simulation (ORSIM) is an automated tool that simulates sequential transfer maneuvers of an orbital maneuvering vehicle (OMV) transporting orbital replaceable units from a space-based depot, or logistics platform, to higher altitude SDI sdatellites. ORSIM calculates OMV energy expenditures (velocity changes) and event histories for various combinations of user-selected orbital transfer maneuvers. Additionally, ORSIM determines the optimal configuration/quantities of logistics platforms and OMVs which conform to the dynamics of differential nodal precession, given user-prescribed values of the scheduled maintenance cycle and required servicing times. ORSIM is coded in FORTRAN-77 and is resident on an IBM PC/AT.

  1. OSO-6 Orbiting Solar Observatory

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The description, development history, test history, and orbital performance analysis of the OSO-6 Orbiting Solar Observatory are presented. The OSO-6 Orbiting Solar Observatory was the sixth flight model of a series of scientific spacecraft designed to provide a stable platform for experiments engaged in the collection of solar and celestial radiation data. The design objective was 180 days of orbital operation. The OSO-6 has telemetered an enormous amount of very useful experiment and housekeeping data to GSFC ground stations. Observatory operation during the two-year reporting period was very successful except for some experiment instrument problems.

  2. Cassini ISS Satellite Orbit Results

    NASA Astrophysics Data System (ADS)

    Spitale, J. N.; Jacobson, R. A.; Porco, C. C.; Owen, W. M.; Charnoz, S.; Murray, C. D.; Brahic, A.; Evans, M. W.; Beurle, K.; Cooper, N.; Cassini Imaging

    2004-11-01

    We report on the orbits of several small Saturnian satellites, either recovered or newly-discovered in recent Cassini imaging observations. The mean motions of Pan and Atlas have been corrected based on recent Cassini imaging combined with Voyager observations. Two small satellites, S/2004 S 1 and S/2004 S 2, have been discovered between the orbits of Mimas and Enceladus on orbits that are nearly circular and uninclined. Both bodies were observed for a fraction of one orbit on June 1, 2004 and S/2004 S 1 was subsequently detected in images shuttered three weeks earlier. Those bodies may be recovered in late October in imaging sequences designed for that purpose. A third new object was detected in images from June 21, 2004, orbiting just outside the F ring. However, a search for additional detections revealed something orbiting interior to the F ring near the longitude at which the new object would be expected 5 hours later. A low-residual orbit that crosses the F ring has been found to explain all of the observations, but it is not yet clear whether the two sequences imaged the same object or two different objects that coincidentally were found orbiting at the same longitude but at different orbital semimajor axes. These issues make its nature -- solid satellite or F ring clump -- unclear. The data, fitting procedures, and results will be discussed.

  3. Imaging of the Postoperative Orbit.

    PubMed

    Learned, Kim O; Nasseri, Farbod; Mohan, Suyash

    2015-08-01

    Imaging evaluation of the postoperative orbit remains challenging even for the expert neuroradiologist. This article provides a simplified framework for understanding the complex postoperative appearances of the orbit, in an attempt to enhance the diagnostic accuracy of postoperative computed tomography and MR imaging of the orbit. Readers are familiarized with the normal appearances of common eye procedures and orbit reconstructions to help avoid interpretative pitfalls. Also reviewed are imaging features of common surgical complications, and evaluation of residual/recurrent neoplasm in the setting of oncologic imaging surveillance.

  4. Orbit Alignment in Triple Stars

    NASA Astrophysics Data System (ADS)

    Tokovinin, Andrei

    2017-08-01

    The statistics of the angle Φ between orbital angular momenta in hierarchical triple systems with known inner visual or astrometric orbits are studied. A correlation between apparent revolution directions proves the partial orbit alignment known from earlier works. The alignment is strong in triples with outer projected separation less than ∼50 au, where the average Φ is about 20^\\circ . In contrast, outer orbits wider than 1000 au are not aligned with the inner orbits. It is established that the orbit alignment decreases with the increasing mass of the primary component. The average eccentricity of inner orbits in well-aligned triples is smaller than in randomly aligned ones. These findings highlight the role of dissipative interactions with gas in defining the orbital architecture of low-mass triple systems. On the other hand, chaotic dynamics apparently played a role in shaping more massive hierarchies. The analysis of projected configurations and triples with known inner and outer orbits indicates that the distribution of Φ is likely bimodal, where 80% of triples have {{Φ }}< 70^\\circ and the remaining ones are randomly aligned.

  5. Orbital molecules in electronic materials

    SciTech Connect

    Attfield, J. Paul

    2015-04-01

    Orbital molecules are made up of coupled orbital states on several metal ions within an orbitally ordered (and sometimes also charge-ordered) solid such as a transition metal oxide. Spin-singlet dimers are known in many materials, but recent discoveries of more exotic species such as 18-electron heptamers in AlV{sub 2}O{sub 4} and magnetic 3-atom trimerons in magnetite (Fe{sub 3}O{sub 4}) have shown that orbital molecules constitute a general new class of quantum electronic states in solids.

  6. New orbit correction method uniting global and local orbit corrections

    NASA Astrophysics Data System (ADS)

    Nakamura, N.; Takaki, H.; Sakai, H.; Satoh, M.; Harada, K.; Kamiya, Y.

    2006-01-01

    A new orbit correction method, called the eigenvector method with constraints (EVC), is proposed and formulated to unite global and local orbit corrections for ring accelerators, especially synchrotron radiation(SR) sources. The EVC can exactly correct the beam positions at arbitrarily selected ring positions such as light source points, simultaneously reducing closed orbit distortion (COD) around the whole ring. Computer simulations clearly demonstrate these features of the EVC for both cases of the Super-SOR light source and the Advanced Light Source (ALS) that have typical structures of high-brilliance SR sources. In addition, the effects of errors in beam position monitor (BPM) reading and steering magnet setting on the orbit correction are analytically expressed and also compared with the computer simulations. Simulation results show that the EVC is very effective and useful for orbit correction and beam position stabilization in SR sources.

  7. Orbital fluctuations and orbital flipping in RVO3 perovskites.

    PubMed

    Yan, J-Q; Zhou, J-S; Goodenough, J B; Ren, Y; Cheng, J G; Chang, S; Zarestky, J; Garlea, O; Llobet, A; Liobet, A; Zhou, H D; Sui, Y; Su, W H; McQueeney, R J

    2007-11-09

    The effect of the average R-site ionic radius IR and variance on the orbital and magnetic order in R3+-doped YVO3 was studied in Y1-xLaxVO3 and Y1-x(La0.2337Lu0.7663)xVO3 with fixed IR. The orbital flipping temperature T{CG} increases nonlinearly with increasing R-site variance, indicating that the V-O-V bond angle is not the primary driving force stabilizing the C-type orbitally ordered phase. The suppressed thermal conductivity in the G-type orbitally ordered phase signals some remaining orbital randomness that is enhanced by t{2} and et hybridization in {3}T{1g} site symmetry.

  8. Orbital Fluctuations and Orbital Flipping in RVO3 Perovskites

    SciTech Connect

    Yan, J.-Q.; Zhou, J.-S.; Goodenough, J. B.; Ren, Y.; Cheng, J. G.; Zarestky, Jerel L; Garlea, Vasile O; Liobet, A.; Zhou, H. D.; Sui, Y.; Su, W. H.; McQueeney, R. J.

    2007-01-01

    The effect of the average A-site ionic radius hIRi and variance on the orbital and magnetic order in R3+-doped YVO3 was studied in Y1-xLaxVO3 and Y1-x(La0.2337Lu0.7663)xVO3 with fixed . The orbital flipping temperature T_CG increases nonlinearly with increasing R-site variance, indicating that the V-O-V bond angle is not the primary driving force stabilizing the C-type orbitally ordered phase. The suppressed thermal conductivity in the G-type orbitally ordered phase signals some remaining orbital randomness that is enhanced by t2 and et hybridization in 3T_1g site symmetry.

  9. Orbital Chondroma: A rare mesenchymal tumor of orbit

    PubMed Central

    Kabra, Ruchi S; Patel, Sonal B; Shanbhag, Swapna S

    2015-01-01

    While relatively common in the skeletal system, cartilaginous tumors are rarely seen originating from the orbit. Here, we report a rare case of an orbital chondroma. A 27-year-old male patient presented with a painless hard mass in the superonasal quadrant (SNQ) of left orbit since 3 months. On examination, best-corrected visual acuity of both eyes was 20/20, with normal anterior and posterior segment with full movements of eyeballs and normal intraocular pressure. Computerized tomography scan revealed well defined soft tissue density lesion in SNQ of left orbit. Patient was operated for anteromedial orbitotomy under general anesthesia. Mass was excised intact and sent for histopathological examination (HPE). HPE report showed lobular aggregates of benign cartilaginous cells with mild atypia suggesting of benign cartilaginous tumor - chondroma. Very few cases of orbital chondroma have been reported in literature so far. PMID:26265654

  10. A Case of Orbital Abscess following Porous Orbital Implant Infection

    PubMed Central

    Hong, Seung Woo; Paik, Ji-Sun; Kim, So-Youl

    2006-01-01

    Purpose We present a case of orbital abscess following porous orbital implant infection in a 73-year-old woman with rheumatoid arthritis. Methods Just one month after a seemingly uncomplicated enucleation and porous polyethylene (Medpor®) orbital implant surgery, implant exposure developed with profuse pus discharge. The patient was unresponsive to implant removal and MRI confirmed the presence of an orbital pus pocket. Despite extirpation of the four rectus muscles, inflammatory granulation debridement and abscess drainage, another new pus pocket developed. Results After partial orbital exenteration, the wound finally healed well without any additional abscess formation. Conclusions A patient who has risk factors for delayed wound healing must be examined thoroughly and extreme care such as exenteration must be taken if there is persistent infection. PMID:17302210

  11. PyORBIT: A Python Shell For ORBIT

    SciTech Connect

    Jean-Francois Ostiguy; Jeffrey Holmes

    2003-07-01

    ORBIT is code developed at SNS to simulate beam dynamics in accumulation rings and synchrotrons. The code is structured as a collection of external C++ modules for SuperCode, a high level interpreter shell developed at LLNL in the early 1990s. SuperCode is no longer actively supported and there has for some time been interest in replacing it by a modern scripting language, while preserving the feel of the original ORBIT program. In this paper, we describe a new version of ORBIT where the role of SuperCode is assumed by Python, a free, well-documented and widely supported object-oriented scripting language. We also compare PyORBIT to ORBIT from the standpoint of features, performance and future expandability.

  12. Sclerosing Orbital Inflammation Caused by Leishmania braziliensis.

    PubMed

    Cruz, Antonio Augusto V; Alves-Ferreira, Eliza V C; Milbratz-Moré, Gherusa; Chahud, Fernando; Ruy, Patricia C; Duarte, Maria Irma Seixas; Cruz, Angela Kaysel

    2017-01-11

    Orbital biopsy of nonspecific orbital inflammation, commonly referred to as "orbital pseudotumor," typically shows a combination of polyclonal lymphocytes, plasmocytes, leukocytes, macrophages, and variable degrees of collagen deposition. Herein, we report a patient with a positive history of mucocutaneous leishmaniasis who presented with an orbital mass with a histological profile of idiopathic orbital inflammation. Immunohistochemical and molecular analysis of the orbital specimens demonstrated that the orbital inflammation was associated with the presence of antigens of Leishmania braziliensis and DNA from the parasite.

  13. Orbital anatomy for the surgeon.

    PubMed

    Turvey, Timothy A; Golden, Brent A

    2012-11-01

    An anatomic description of the orbit and its contents and the eyelids directed toward surgeons is the focus of this article. The bone and soft tissue anatomic nuances for surgery are highlighted, including a section on osteology, muscles, and the orbital suspensory system. Innervation and vascular anatomy are also addressed.

  14. Diffractive molecular-orbital tomography

    NASA Astrophysics Data System (ADS)

    Zhai, Chunyang; Zhu, Xiaosong; Lan, Pengfei; Wang, Feng; He, Lixin; Shi, Wenjing; Li, Yang; Li, Min; Zhang, Qingbin; Lu, Peixiang

    2017-03-01

    High-order-harmonic generation in the interaction of femtosecond lasers with atoms and molecules opens the path to molecular-orbital tomography and to probe the electronic dynamics with attosecond-Ångström resolutions. Molecular-orbital tomography requires both the amplitude and phase of the high-order harmonics. Yet the measurement of phases requires sophisticated techniques and represents formidable challenges at present. Here we report a scheme, called diffractive molecular-orbital tomography, to retrieve the molecular orbital solely from the amplitude of high-order harmonics without measuring any phase information. We have applied this method to image the molecular orbitals of N2, CO2, and C2H2 . The retrieved orbital is further improved by taking account the correction of Coulomb potential. The diffractive molecular-orbital tomography scheme, removing the roadblock of phase measurement, significantly simplifies the molecular-orbital tomography procedure and paves an efficient and robust way to the imaging of more complex molecules.

  15. Safety in earth orbit study

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Safety aspects are studied of the space shuttle orbiter, the shuttle payloads, and space stations in earth orbital operations. The tasks generated safety requirements, guidelines, recommendations, and conceptual safety devices. The tasks studied were: hazardous payloads, docking, onboard survivability tumbling spacecraft, and escape and rescue operations.

  16. Antibiotic Prophylaxis in Orbital Fractures

    PubMed Central

    Reiss, Benjamin; Rajjoub, Lamise; Mansour, Tamer; Chen, Tony; Mumtaz, Aisha

    2017-01-01

    Purpose: To determine whether prophylactic antibiotic use in patients with orbital fracture prevent orbital infection. Design: Retrospective cohort study. Participants: All patients diagnosed with orbital fracture between January 1, 2008 and March 1, 2014 at The George Washington University Hospital and Clinics. Main Outcome Measures: Development of orbital infection. Results: One hundred seventy-two patients with orbital fracture met our inclusion and exclusion criteria. No orbital infections were documented. Twenty subjects (12%) received no prophylactic antibiotic, and two (1%) received only one dose of antibiotics pre-operatively for surgery. For primary antibiotic, 136 subjects (79%) received oral antibiotics, and 14 (8%) received intravenous (IV) antibiotics (excluding cefazolin). Cephalexin and amoxicillin-clavulanate were the most prescribed oral antibiotics that are equally effective. Five-to-seven day courses of antibiotics had no increased infections compared to ten-to-fourteen day courses. Calculated boundaries for effectiveness of prophylactic antibiotics ranged from a Number Needed to Treat (NNT) of 75 to a Number Needed to Harm (NNH) of 198. Conclusion: Antibiotics for prevention of orbital infection in patients with orbital fractures have become widely used. Coordination between trauma teams and specialists is needed to prevent patient overmedication and antibiotic resistance. Should antibiotics be used, shorter courses and avoidance of broad spectrum agents are recommended. Additional studies are needed. PMID:28400887

  17. Unilateral orbital emphysema after sneezing.

    PubMed

    Koçak, Nilüfer; Oztürk, Taylan; Zengin, Mehmet Ozgür; Kaynak, Süleyman; Men, Süleyman

    2009-01-01

    We report a case who developed unilateral orbital emphysema after sneezing in a 30-year-old man presented with left crepitant eyelid swelling and progressive ptosis. Sneezing may cause orbital emphysema in cases with a history of minor periorbital trauma. While periodical followup without any medication is considered satisfactory, needle decompression may provide early cure.

  18. Deputy Admin. Tours Orbital Sciences

    NASA Image and Video Library

    2011-01-11

    NASA Deputy Administrator Lori Garver, left, and White House Office of Science and Technology Chief of Staff Jim Kohlenberger, right, listen to Mr. David W. Thompson, Chairman and Chief Executive Officer Orbital Sciences Corporation as he gives a tour of the Orbital Sciences facilities on Tuesday, Jan. 11, 2011 in Dulles, VA. Photo Credit: (NASA/Bill Ingalls)

  19. SIRTF in high earth orbit

    NASA Technical Reports Server (NTRS)

    Werner, Michael W.; Brooks, Walter F.; Manning, Larry A.; Eisenhardt, Peter

    1989-01-01

    The goals, requirements and operation of the Space Infrared Telescope Facility (SIRTF) are discussed. Emphasis is upon an analysis of the options of high and low earth orbits for the mission. The consensus was that the high earth orbit offers significant scientific and engineering advantages for SIRTF.

  20. [Enophthalmos in an orbital tumor].

    PubMed

    Szabo, Bianca; Szabo, I; Nicula, Cristina; Popescu, Livia Adriana

    2013-01-01

    Enophtalmus is an unusual sign of the orbital tumors often represented by proptosis. One patient with enophtalmus and intraorbital tumor and aplasy is presented. The treatment of choice of orbital tumor is complete surgical excision and careful follow-up. Considering the more aggressive course followed by recurrent tumor, correct diagnosis and management is essential.

  1. Low Earth Orbiter: Terminal

    NASA Technical Reports Server (NTRS)

    Kremer, Steven E.; Bundick, Steven N.

    1999-01-01

    In response to the current government budgetary environment that requires the National Aeronautics and Space Administration (NASA) to do more with less, NASA/Goddard Space Flight Center's Wallops Flight Facility has developed and implemented a class of ground stations known as a Low Earth Orbiter-Terminal (LEO-T). This development thus provides a low-cost autonomous ground tracking service for NASA's customers. More importantly, this accomplishment provides a commercial source to spacecraft customers around the world to purchase directly from the company awarded the NASA contract to build these systems. A few years ago, NASA was driven to provide more ground station capacity for spacecraft telemetry, tracking, and command (TT&C) services with a decreasing budget. NASA also made a decision to develop many smaller, cheaper satellites rather than a few large spacecraft as done in the past. In addition, university class missions were being driven to provide their own TT&C services due to the increasing load on the NASA ground-tracking network. NASA's solution for this ever increasing load was to use the existing large aperture systems to support those missions requiring that level of performance and to support the remainder of the missions with the autonomous LEO-T systems. The LEO-T antenna system is a smaller, cheaper, and fully autonomous unstaffed system that can operate without the existing NASA support infrastructure. The LEO-T provides a low-cost, reliable space communications service to the expanding number of low-earth orbiting missions around the world. The system is also fostering developments that improve cost-effectiveness of autonomous-class capabilities for NASA and commercial space use. NASA has installed three LEO-T systems. One station is at the University of Puerto Rico, the second system is installed at the Poker Flat Research Range near Fairbanks, Alaska, and the third system is installed at NASA's Wallops Flight Facility in Virginia. This paper

  2. Low Earth Orbiter: Terminal

    NASA Technical Reports Server (NTRS)

    Kremer, Steven E.; Bundick, Steven N.

    1999-01-01

    In response to the current government budgetary environment that requires the National Aeronautics and Space Administration (NASA) to do more with less, NASA/Goddard Space Flight Center's Wallops Flight Facility has developed and implemented a class of ground stations known as a Low Earth Orbiter-Terminal (LEO-T). This development thus provides a low-cost autonomous ground tracking service for NASA's customers. More importantly, this accomplishment provides a commercial source to spacecraft customers around the world to purchase directly from the company awarded the NASA contract to build these systems. A few years ago, NASA was driven to provide more ground station capacity for spacecraft telemetry, tracking, and command (TT&C) services with a decreasing budget. NASA also made a decision to develop many smaller, cheaper satellites rather than a few large spacecraft as done in the past. In addition, university class missions were being driven to provide their own TT&C services due to the increasing load on the NASA ground-tracking network. NASA's solution for this ever increasing load was to use the existing large aperture systems to support those missions requiring that level of performance and to support the remainder of the missions with the autonomous LEO-T systems. The LEO-T antenna system is a smaller, cheaper, and fully autonomous unstaffed system that can operate without the existing NASA support infrastructure. The LEO-T provides a low-cost, reliable space communications service to the expanding number of low-earth orbiting missions around the world. The system is also fostering developments that improve cost-effectiveness of autonomous-class capabilities for NASA and commercial space use. NASA has installed three LEO-T systems. One station is at the University of Puerto Rico, the second system is installed at the Poker Flat Research Range near Fairbanks, Alaska, and the third system is installed at NASA's Wallops Flight Facility in Virginia. This paper

  3. Video Orbits of the Geminids

    NASA Astrophysics Data System (ADS)

    Hajdukova, M.

    2014-07-01

    Geminid meteoroids, observed by the video technique, were analysed with the aim of determining the actual dispersion of their reciprocal semimajor axes 1/a within the stream. Orbits were selected from the European Video Meteor Network Database, EDMOND, (Kornos et al., 2013), from the SonotaCo Shower Catalogue (SonotaCo, 2009), and from the Czech Catalogue of Video Meteor Orbits (Koten et al., 2003). The observed orbital dispersion, including the measurement errors, was compared with that obtained from the precisely-reduced photographic orbits of Geminids from the IAU Meteor Data Center (Lindblad et al., 2003). In this paper, we concentrate on the influence of errors on the orbital dispersion. The size and distribution of observational errors determined from the long-period meteoroid streams (Hajdukova 2013), were applied to determine the real dispersion within this short-period meteoroid stream. The observed dispersions, described by the median absolute deviation in terms of 1/a, range from 0.041 to 0.050 1/au. The deviation of the median reciprocal semimajor axis from the parent (3200) Phaethon, obtained from Japanese video orbits, is 0.009 1/au, and that from the EDMOND data 0.01 1/au. This deviation obtained from the photographic orbits of the IAU Meteor Data Center was significantly greater (Hajdukova 2009). Similar results were obtained from the Czech Video Orbits Catalogue, where the value is 0.05 1/au. The investigation showed that semimajor axes of meteor orbits in both the SonotaCo and EDMOND datasets are systematically biased as a consequence of the method used for the video orbit determination, probably because corrections for atmospheric deceleration were either incorrectly made or were not done at all. Thus, the determined heliocentric velocities are underestimated, and the semimajor axes medians shifted towards smaller values. The observed distributions in 1/a from these video data become biased towards higher values of 1/a. The orbits of the Geminid

  4. General relativity and satellite orbits

    NASA Technical Reports Server (NTRS)

    Rubincam, D. P.

    1975-01-01

    The general relativistic correction to the position of a satellite is found by retaining Newtonian physics for an observer on the satellite and introducing a potential. The potential is expanded in terms of the Keplerian elements of the orbit and substituted in Lagrange's equations. Integration of the equations shows that a typical earth satellite with small orbital eccentricity is displaced by about 17 cm. from its unperturbed position after a single orbit, while the periodic displacement over the orbit reaches a maximum of about 3 cm. The moon is displaced by about the same amounts. Application of the equations to Mercury gives a total displacement of about 58 km. after one orbit and a maximum periodic displacement of about 12 km.

  5. Floating orbital molecular dynamics simulations.

    PubMed

    Perlt, Eva; Brüssel, Marc; Kirchner, Barbara

    2014-04-21

    We introduce an alternative ab initio molecular dynamics simulation as a unification of Hartree-Fock molecular dynamics and the floating orbital approach. The general scheme of the floating orbital molecular dynamics method is presented. Moreover, a simple but sophisticated guess for the orbital centers is provided to reduce the number of electronic structure optimization steps at each molecular dynamics step. The conservation of total energy and angular momentum is investigated in order to validate the floating orbital molecular dynamics approach with and without application of the initial guess. Finally, a water monomer and a water dimer are simulated, and the influence of the orbital floating on certain properties like the dipole moment is investigated.

  6. Halo orbit to science orbit captures at planetary moons

    NASA Astrophysics Data System (ADS)

    Bokelmann, Kevin A.; Russell, Ryan P.

    2017-05-01

    Ballisticly connecting halo orbits to science orbits in the circular-restricted three-body problem is investigated. Two classes of terminal science orbits are considered: low-altitude, tight orbits that are deep in the gravity well of the secondary body, and high-altitude, loose orbits that are strongly perturbed by the gravity of the primary body. General analytic expressions are developed to provide a minimum bound on impulse cost in both the circular restricted and the Hill's approximations. The equations are applied to a broad range of planetary moons, providing a mission design reference. Systematic grid search methods are developed to numerically find feasible transfers from halo orbits at Europa, confirming the analytical lower bound formulas. The two-impulse capture options in the case of Europa reveal a diverse set of potential solutions. Tight captures result in maneuver costs of 425-550 m/s while loose captures are found with costs as low as 30 m/s. The terminal orbits are verified to avoid escape or impact for at least 45 days.

  7. HEO space debris orbit predictions.

    NASA Astrophysics Data System (ADS)

    Gregorowicz, Dorota; Pospieszynski, Remigiusz; Golembiewska, Justyna; Wnuk, Edwin

    2012-07-01

    HEO (Highly Elliptical Orbit) satellites are objects with an elliptic orbit with a low-altitude perigee and a high-altitude apogee. Perigee mainly cross the LEO orbits and apogee reaches regions above GEO orbits. Number of satellites on the orbits are old racket bodies and other space debris. Most of HEO objects has the eccentricity more than 0.7. Many trackable objects are included in the NORAD TLE Catalogue but much more small debris exist which we could not track. Objects on as highly elliptical orbit are very danger for satellites in LEO region because of increasing velocity near the perigee. In order to calculate the trajectory of space debris we have to take into account force model consisting of geopotential, luni-solar effects, solar radiation pressure and for objects with low-altitude of perigee, atmospheric drag. This last perturbation is very important to calculate orbits with high accuracy but also one of the hardest to predict. Many atmospheric space debris objects parameters should be taken into account in this case, but we do not have sufficient data from observations, in particular S/M (area-to-mass) ratio. Fortunately we have some archival data for some debris included in TLE Catalogue, which are very helpful to estimate the approximate value of the parameter. In this paper we present the results of calculations of orbit predictions for short and medium time span (up to several weeks). We tried to designate the S/M parameter for some HEO objects from archival data from the TLE Catalogue and predict its orbital elements for several weeks. With better knowledge about approximate mean value of the S/M parameter we are able to improve the accuracy of predicted orbits.

  8. Orbital angular momentum entanglement

    NASA Astrophysics Data System (ADS)

    Romero, Mary Jacquiline Romero

    Entanglement in higher dimensions is an attractive concept that is a challenge to realise experimentally. To this end, the entanglement of the orbital angular momentum (OAM) of photons holds promise. The OAM state-space is discrete and theoretically unbounded. In the work that follows, we investigate various aspects of OAM entanglement. We show how the correlations in OAM and its conjugate variable, angular position, are determined by phase- matching and the shape of the pump beam in spontaneous parametric down- conversion. We implement tests of quantum mechanics which have been previously done for other variables. We show the Einstein-Podolsky-Rosen paradox for OAM and angle, supporting the incompatibility of quantum mechanics with locality and realism. We demonstrate violations of Bell-type inequalities, thereby discounting local hidden variables for describing the correlations we observe. We show the Hardy paradox using OAM, again highlighting the nonlocal nature of quantum mechanics. We demonstrate violations of Leggett-type inequalities, thereby discounting nonlocal hidden variables for describing correlations. Lastly, we have looked into the entanglement of topological vortex structures formed from a special superposition of OAM modes and show violations of Bell-type inequalities confined to a finite, isolated volume.

  9. VSOP-2 Orbit Determination

    NASA Astrophysics Data System (ADS)

    Takeuchi, H.; VSOP-2 Orbit Determination Sub-Working Group

    2009-08-01

    Precise orbit determination (POD) is a key factor to enable phase referencing observations with Astro-G. A POD accuracy of 30 cm is required for efficient X-band phase referencing observations, accuracy of 6 cm for K-band observations, and accuracy of 3 cm for Q-band observations. For the POD, Astro-G will be equipped with a GPS/Galileo receiver and a SLR (Satellite Laser Ranging) retroreflector array. Four POD antennas will be equipped on four sides of the satellite body, to cover all directions. The SLR will be used as a complement to the GPS at middle-to-high altitude. Because the refroreflector array should always face to the Earth direction, it will be set up on the Ka-link antenna gimbal. The most significant perturbing force for the Astro-G is solar radiation pressure (SRP). The reflectivity of each surface component should be preliminary measured in detail to model the SRP. The estimated achievable POD accuracy at apogee is 10 ˜ 30 cm in nominal case. Phase referencing observations in K- or Q-band can be performed if the enough amount of SLR tracking data can be obtained at high altitudes.

  10. Orbiter Camera Payload System

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Components for an orbiting camera payload system (OCPS) include the large format camera (LFC), a gas supply assembly, and ground test, handling, and calibration hardware. The LFC, a high resolution large format photogrammetric camera for use in the cargo bay of the space transport system, is also adaptable to use on an RB-57 aircraft or on a free flyer satellite. Carrying 4000 feet of film, the LFC is usable over the visible to near IR, at V/h rates of from 11 to 41 milliradians per second, overlap of 10, 60, 70 or 80 percent and exposure times of from 4 to 32 milliseconds. With a 12 inch focal length it produces a 9 by 18 inch format (long dimension in line of flight) with full format low contrast resolution of 88 lines per millimeter (AWAR), full format distortion of less than 14 microns and a complement of 45 Reseau marks and 12 fiducial marks. Weight of the OCPS as supplied, fully loaded is 944 pounds and power dissipation is 273 watts average when in operation, 95 watts in standby. The LFC contains an internal exposure sensor, or will respond to external command. It is able to photograph starfields for inflight calibration upon command.

  11. Precision Orbit Determination for the Lunar Reconnaissance Orbiter

    NASA Astrophysics Data System (ADS)

    Lemoine, F. G.; Mazarico, E.; Rowlands, D. D.; Torrence, M. H.; McGarry, J. F.; Neumann, G. A.; Mao, D.; Smith, D. E.; Zuber, M. T.

    2010-05-01

    The Lunar Reconnaissance Orbiter (LRO) spacecraft was launched on June 18, 2009. In mid-September 2009, the spacecraft orbit was changed from its commissioning orbit (30 x 216 km polar) to a quasi-frozen polar orbit with an average altitude of 50km (+-15km). One of the goals of the LRO mission is to develop a new lunar reference frame to facilitate future exploration. Precision Orbit Determination is used to achieve the accuracy requirements, and to precisely geolocate the high-resolution datasets obtained by the LRO instruments. In addition to the tracking data most commonly used to determine spacecraft orbits in planetary missions (radiometric Range and Doppler), LRO benefits from two other types of orbital constraints, both enabled by the Lunar Orbiter Laser Altimeter (LOLA) instrument. The altimetric data collected as the instrument's primary purpose can be used to derive constraints on the orbit geometry at the times of laser groundtrack intersections (crossovers). The multi-beam configuration and high firing-rate of LOLA further improves the strength of these crossovers, compared to what was possible with the MOLA instrument onboard Mars Global Surveyor (MGS). Furthermore, one-way laser ranges (LR) between Earth International Laser Ranging Service (ILRS) stations and the spacecraft are made possible by the addition of a small telescope mounted on the spacecraft high-gain antenna. The photons received from Earth are transmitted to one LOLA detector by a fiber optics bundle. Thanks to the accuracy of the LOLA timing system, the precision of 5-s LR normal points is below 10cm. We present the first results of the Precision Orbit Determination (POD) of LRO through the commissioning and nominal phases of the mission. Orbit quality is discussed, and various gravity fields are evaluated with the new (independent) LRO radio tracking data. The altimetric crossovers are used as an independent data type to evaluate the quality of the orbits. The contribution of the LR

  12. Solid Propulsion De-Orbiting and Re-Orbiting

    NASA Astrophysics Data System (ADS)

    Schonenborg, R. A. C.; Schoyer, H. F. R.

    2009-03-01

    With many "innovative" de-orbit systems (e.g. tethers, aero breaking, etc.) and with natural de-orbit, the place of impact of unburned spacecraft debris on Earth can not be determined accurately. The idea that satellites burn up completely upon re-entry is a common misunderstanding. To the best of our knowledge only rocket motors are capable of delivering an impulse that is high enough, to conduct a de-orbit procedure swiftly, hence to de-orbit at a specific moment that allows to predict the impact point of unburned spacecraft debris accurately in remote areas. In addition, swift de-orbiting will reduce the on-orbit time of the 'dead' satellite, which reduces the chance of the dead satellite being hit by other dead or active satellites, while spiralling down to Earth during a slow, 25 year, or more, natural de-orbit process. Furthermore the reduced on-orbit time reduces the chance that spacecraft batteries, propellant tanks or other components blow up and also reduces the time that the object requires tracking from Earth.The use of solid propellant for the de-orbiting of spacecraft is feasible. The main advantages of a solid propellant based system are the relatively high thrust and the facts that the system can be made autonomous quite easily and that the system can be very reliable. The latter is especially desirable when one wants to de-orbit old or 'dead' satellites that might not be able to rely anymore on their primary systems. The disadvantage however, is the addition of an extra system to the spacecraft as well as a (small) mass penalty. [1]This paper describes the above mentioned system and shows as well, why such a system can also be used to re-orbit spacecraft in GEO, at the end of their life to a graveyard orbit.Additionally the system is theoretically compared to an existing system, of which performance data is available.A swift market analysis is performed as well.

  13. Orbit Determination System for Low Earth Orbit Satellites

    NASA Technical Reports Server (NTRS)

    Elisha, Yossi; Shyldkrot, Haim; Hankin, Maxim

    2007-01-01

    The IAI/MBT Precise Orbit Determination system for Low Earth Orbit satellites is presented. The system is based on GPS pesudorange and carrier phase measurements and implements the Reduced Dynamics method. The GPS measurements model, the dynamic model, and the least squares orbit determination are discussed. Results are shown for data from the CHAMP satellite and for simulated data from the ROKAR GPS receiver. In both cases the one sigma 3D position and velocity accuracy is about 0.2 m and 0.5 mm/sec respectively.

  14. Radiation therapy for orbital lymphoma

    SciTech Connect

    Zhou Ping . E-mail: pzhou@partners.org; Ng, Andrea K.; Silver, Barbara; Li Sigui; Hua Ling; Mauch, Peter M.

    2005-11-01

    Purpose: To describe radiation techniques and evaluate outcomes for orbital lymphoma. Methods and Materials: Forty-six patients (and 62 eyes) with orbital lymphoma treated with radiotherapy between 1987 and 2003 were included. The majority had mucosa-associated lymphoid tissue (48%) or follicular (30%) lymphoma. Seventeen patients had prior lymphoma at other sites, and 29 had primary orbital lymphoma. Median follow-up was 46 months. Results: The median dose was 30.6 Gy; one-third received <30 Gy. Electrons were used in 9 eyes with disease confined to the conjunctiva or eyelid, and photons in 53 eyes with involvement of intraorbital tissues to cover entire orbit. Local control rate was 98% for all patients and 100% for those with indolent lymphoma. Three of the 26 patients with localized primary lymphoma failed distantly, resulting in a 5-year freedom-from-distant-relapse rate of 89%. The 5-year disease-specific and overall survival rates were 95% and 88%, respectively. Late toxicity was mainly cataract formation in patients who received radiation without lens block. Conclusions A dose of 30 Gy is sufficient for indolent orbital lymphoma. Distant relapse rate in patients with localized orbital lymphoma was lower than that reported for low-grade lymphoma presenting in other sites. Orbital radiotherapy can be used for salvage of recurrent indolent lymphoma.

  15. Lifetimes of lunar satellite orbits

    NASA Technical Reports Server (NTRS)

    Meyer, Kurt W.; Buglia, James J.; Desai, Prasun N.

    1994-01-01

    The Space Exploration Initiative has generated a renewed interest in lunar mission planning. The lunar missions currently under study, unlike the Apollo missions, involve long stay times. Several lunar gravity models have been formulated, but mission planners do not have enough confidence in the proposed models to conduct detailed studies of missions with long stay times. In this report, a particular lunar gravitational model, the Ferrari 5 x 5 model, was chosen to determine the lifetimes for 100-km and 300-km perilune altitude, near-circular parking orbits. The need to analyze orbital lifetimes for a large number of initial orbital parameters was the motivation for the formulation of a simplified gravitational model from the original model. Using this model, orbital lifetimes were found to be heavily dependent on the initial conditions of the nearly circular orbits, particularly the initial inclination and argument of perilune. This selected model yielded lifetime predictions of less than 40 days for some orbits, and other orbits had lifetimes exceeding a year. Although inconsistencies and limitations are inherent in all existing lunar gravity models, primarily because of a lack of information about the far side of the moon, the methods presented in this analysis are suitable for incorporating the moon's nonspherical gravitational effects on the preliminary design level for future lunar mission planning.

  16. Space Telescopes and Orbital Debris

    NASA Astrophysics Data System (ADS)

    Seitzer, Patrick

    2009-01-01

    Almost 12,000 artificial objects orbiting the Earth are currently in the public catalog of orbital elements maintained by the USAF. Only a small fraction of them are operational satellites. The remainder is satellites whose missions have ended, rocket bodies, and parts and debris from larger parent objects. And the catalog only contains the biggest and brightest of the objects in orbit. The Low Earth Orbit (LEO) regime where most of this population concentrates is also a regime of incredible interest to astronomers, since it is where flagship missions such as the Hubble Space Telescope and other Great Observatories operate. I'll review the current state of knowledge of the orbital debris population, how it has grown with time, and how this environment could affect current and future space telescopes. There are mitigation measures which many spacecraft operators have adopted which can control the growth of the debris population. Orbital debris research at the University of Michigan is funded by NASA's Orbital Debris Program Office, Johnson Space Center, Houston, Texas.

  17. Diplopia and orbital wall fractures.

    PubMed

    Boffano, Paolo; Roccia, Fabio; Gallesio, Cesare; Karagozoglu, K Hakki; Forouzanfar, Tymour

    2014-01-01

    Diplopia is a symptom that is frequently associated with orbital wall fractures. The aim of this article was to present the incidence and patterns of diplopia after orbital wall blow-out fractures in 2 European centers, Turin and Amsterdam, and to identify any correlation between this symptom and such fractures. This study is based on 2 databases that have continuously recorded data of patients hospitalized with maxillofacial fractures between 2001 and 2010. On the whole, 447 patients (334 males, 113 females) with pure blow-out orbital wall fractures were included. The most frequently involved orbital site was the floor (359 fractures), followed by medial wall (41 fractures) and lateral wall (5 fractures). At presentation, 227 patients (50.7%) had evidence of diplopia. In particular, in most patients, a diplopia in all directions was referred (78 patients). Statistically significant associations were found between diplopia on eye elevation and orbital floor fractures (P < 0.05) and between horizontal diplopia and medial wall fractures (P < 0.000005). In patients under evaluation for orbital trauma, the observation of diplopia on eye elevation and horizontal diplopia at presentation could be useful clinical indicators orbital floor and medial wall fractures, respectively.

  18. Mab's orbital motion explained

    NASA Astrophysics Data System (ADS)

    Kumar, K.; de Pater, I.; Showalter, M. R.

    2015-07-01

    We explored the hypothesis that Mab's anomalous orbital motion, as deduced from Hubble Space Telescope (HST) data (Showalter, M.R., Lissauer, J.J. [2006]. Science (New York, NY) 311, 973-977), is the result of gravitational interactions with a putative suite of large bodies in the μ-ring. We conducted simulations to compute the gravitational effect of Mab (a recently discovered Uranian moon) on a cloud of test particles. Subsequently, by employing the data extracted from the test particle simulations, we executed random walk simulations to compute the back-reaction of nearby perturbers on Mab. By generating simulated observation metrics, we compared our results to the data retrieved from the HST. Our results indicate that the longitude residual change noted in the HST data (Δλr,Mab ≈ 1 deg) is well matched by our simulations. The eccentricity variations (ΔeMab ≈10-3) are however typically two orders of magnitude too small. We present a variety of reasons that could account for this discrepancy. The nominal scenario that we investigated assumes a perturber ring mass (mring) of 1 mMab (Mab's mass) and a perturber ring number density (ρn,ring) of 10 perturbers per 3 RHill,Mab (Mab's Hill radius). This effectively translates to a few tens of perturbers with radii of approximately 2-3 km, depending on the albedo assumed. The results obtained also include an interesting litmus test: variations of Mab's inclination on the order of the eccentricity changes should be observable. Our work provides clues for further investigation into the tantalizing prospect that the Mab/μ-ring system is undergoing re-accretion after a recent catastrophic disruption.

  19. Meteoroid and orbital debris shielding on the Orbital Maneuvering Vehicle

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, Marc E.

    1989-01-01

    NASA's Orbital Maneuvering Vehicle (OMV) is being designed to withstand a 10-year lifetime in polar and low earth orbits. A large percentage of OMV's lifetime will be spent operating in the vicinity of the Space Shuttle and Space Station or in storage at these manned locations. An extensive analysis has been performed to determine the effects of the meteoroid and orbital debris environments on OMV's external fuel tanks. A finite element model of OMV was constructed using NASTRAN and analyzed with the meteoroid and debris design analysis code BUMPER. The results show that the long design lifetime, and the ever increasing man-made orbital debris environment, will require the use of shielding over the external fuel tanks.

  20. Orbital Infarction due to Sickle Cell Disease without Orbital Pain

    PubMed Central

    Mai, Kim-Binh T.

    2016-01-01

    Sickle cell disease is a hemoglobinopathy that results in paroxysmal arteriolar occlusion and tissue infarction that can manifest in a plurality of tissues. Rarely, these infarcted crises manifest in the bony orbit. Orbital infarction usually presents with acute onset of periorbital tenderness, swelling, erythema, and pain. Soft tissue swelling can result in proptosis and attenuation of extraocular movements. Expedient diagnosis of sickle cell orbital infarction is crucial because this is a potentially sight-threatening entity. Diagnosis can be delayed since the presentation has physical and radiographic findings mimicking various infectious and traumatic processes. We describe a patient who presented with sickle cell orbital crisis without pain. This case highlights the importance of maintaining a high index of suspicion in patients with known sickle cell disease or of African descent born outside the United States in a region where screening for hemoglobinopathy is not routine, even when the presentation is not classic. PMID:27891273

  1. Orbit Determination with Very Short Arcs: Preliminary Orbits and Identifications

    NASA Astrophysics Data System (ADS)

    Milani, A.; Gronchi, G. F.; Knezevic, Z.; Sansaturio, M. E.

    2004-05-01

    When the observation of a new asteroid are not enough to compute an orbit we can represent them with an attributable (two angles and their time derivatives). The undetermined range and range rate span an admissible region of solar system orbits, which can be represented by a set of Virtual Asteroids (VAs) selected by an optimal triangulation (see the presentation by G. Gronchi). The four coordinates of the attributable are the result of a fit and have a covariance matrix. Thus the predictions of future observations have a quasi-product structure (admissible region times confidence ellipsoid), approximated by a triangulation with a confidence ellipsoid for each node. If we have >2 observations we can also estimate the geodetic curvature and the acceleration of the observed path on the celestial sphere. If both are significantly measured they constrain the range and the range rate and may allow to reduce the size of the admissible region. To compute a a preliminary orbit starting from two attributables, for each VA (selected in the admissible region of the first arc) we consider the prediction at the time of the second and its covariance matrix, and we compare them with the attributable of the second arc with its covariance. By using the identification penalty (as in the algorithms for orbit identification) we can select as a preliminary orbit the VAs which fits together both arcs in the 8-dimensional space. Two attributables may not be enough to compute an orbit with convergent differential corrections. The preliminary orbit is used in a constrained differential correction, providing solutions along the Line Of Variations, to be used as second generation VAs to predict the observations at the time of a third arc. In general the identification with a third arc ensures a well determined orbit.

  2. Orbital problems in GPS interferometry

    NASA Astrophysics Data System (ADS)

    Zielinski, Janusz B.

    The GPS orbits and the influence of the orbital errors on the geodetic determination were investigated during the last few years. In the paper, the summary of some analyses is presented concerning the nature of the interferometric observations, the propagation of the orbital errors, and the correlations and covariances in geodetic GPS solutions. One of the results was a proof that, in relative determinations by GPS, the error propagation factor is close to b/10 h, that is almost one order smaller than previously supposed.

  3. Orbiter Atlantis returns to KSC

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Shuttle Carrier Aircraft gently lands its piggyback cargo - - orbiter Atlantis -- at the Shuttle Landing Facility. Atlantis returns home after a 10-month stay in the Palmdale, CA, orbiter processing facility undergoing extensive inspections and modifications. They included several upgrades enabling it to support International Space Station missions, such as adding an external airlock for ISS docking missions and installing thinner, lighter thermal protection blankets for weight reduction which will allow it to haul heavier cargo. The flight from Palmdale included a fueling stop in Ft. Hood, TX, and overnight stay at Ft. Campbell, KY. Atlantis will undergo preparations in the Orbiter Processing Facility at KSC for its planned flight in June 1999.

  4. Ocular complications of orbital venography.

    PubMed

    Safer, J N; Guibor, P

    1975-03-01

    Three ocular complications directly related to orbital venography are described, one resulting in permanent loss of vision,. The patient had lymphangioma of the orbit which evidently had bled secondary to increased venous pressure and injection of contrast bolus. Both of the 2 patients with transient visual disturbances had diabetic retinopathy. The common factor is felt to be an imparied vascular bed which cannot meet the stress of increased venous pressure and contrast medium injection. Conditions which predispose to ocular-orbital stasis and/or hemorrhage are discussed.

  5. Proliferative Fasciitis of the Orbit.

    PubMed

    Bautista, Michael J; Perumal, Balaji; Jones, David M; Meyer, Dale R

    Proliferative fasciitis is a rare entity in the orbit. A 16-year-old boy presented with a growing right orbital mass, which was palpable just inferior to the medial right eyebrow. MRI demonstrated a 12 × 8 × 9 mm mass located medial to and slightly above the right globe within the subcutaneous soft tissues. An anterior orbitotomy with debulking of the lesion was performed. Histopathological examination confirmed a diagnosis of proliferative fasciitis. To the authors' knowledge, there is only one prior case in the literature demonstrating proliferative fasciitis of the orbit.

  6. Mars Science Laboratory Orbit Determination

    NASA Technical Reports Server (NTRS)

    Kruizinga, Gerhard L.; Gustafson, Eric D.; Thompson, Paul F.; Jefferson, David C.; Martin-Mur, Tomas J.; Mottinger, Neil A.; Pelletier, Frederic J.; Ryne, Mark S.

    2012-01-01

    This paper describes the orbit determination process, results and filter strategies used by the Mars Science Laboratory Navigation Team during cruise from Earth to Mars. The new atmospheric entry guidance system resulted in an orbit determination paradigm shift during final approach when compared to previous Mars lander missions. The evolving orbit determination filter strategies during cruise are presented. Furthermore, results of calibration activities of dynamical models are presented. The atmospheric entry interface trajectory knowledge was significantly better than the original requirements, which enabled the very precise landing in Gale Crater.

  7. Orbital, Rotational, and Climatic Interactions

    NASA Technical Reports Server (NTRS)

    Bills, Bruce G. (Editor)

    1992-01-01

    The report of an international meeting on the topic of Orbital, Rotational, and Climatic Interactions, which was held 9-11 Jul. 1991 at the Johns Hopkins University is presented. The meeting was attended by 22 researchers working on various aspects of orbital and rotational dynamics, paleoclimate data analysis and modeling, solid-Earth deformation studies, and paleomagnetic analyses. The primary objective of the workshop was to arrive at a better understanding of the interactions between the orbital, rotational, and climatic variations of the Earth. This report contains a brief introduction and 14 contributed papers which cover most of the topics discussed at the meeting.

  8. JSC Orbital Debris Website Description

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas L.

    2006-01-01

    Purpose: The website provides information about the NASA Orbital Debris Program Office at JSC, which is the lead NASA center for orbital debris research. It is recognized world-wide for its leadership in addressing orbital debris issues. The NASA Orbital Debris Program Office has taken the international lead in conducting measurements of the environment and in developing the technical consensus for adopting mitigation measures to protect users of the orbital environment. Work at the center continues with developing an improved understanding of the orbital debris environment and measures that can be taken to control its growth. Major Contents: Orbital Debris research is divided into the following five broad efforts. Each area of research contains specific information as follows: 1) Modeling - NASA scientists continue to develop and upgrade orbital debris models to describe and characterize the current and future debris environment. Evolutionary and engineering models are described in detail. Downloadable items include a document in PDF format and executable software. 2) Measurements - Measurements of near-Earth orbital debris are accomplished by conducting ground-based and space-based observations of the orbital debris environment. The data from these sources provide validation of the environment models and identify the presence of new sources. Radar, optical and surface examinations are described. External links to related topics are provided. 3) Protection - Orbital debris protection involves conducting hypervelocity impact measurements to assess the risk presented by orbital debris to operating spacecraft and developing new materials and new designs to provide better protection from the environment with less weight penalty. The data from this work provides the link between the environment defined by the models and the risk presented by that environment to operating spacecraft and provides recommendations on design and operations procedures to reduce the risk as

  9. JSC Orbital Debris Website Description

    NASA Astrophysics Data System (ADS)

    Johnson, Nicholas L.

    2006-01-01

    Purpose: The website provides information about the NASA Orbital Debris Program Office at JSC, which is the lead NASA center for orbital debris research. It is recognized world-wide for its leadership in addressing orbital debris issues. The NASA Orbital Debris Program Office has taken the international lead in conducting measurements of the environment and in developing the technical consensus for adopting mitigation measures to protect users of the orbital environment. Work at the center continues with developing an improved understanding of the orbital debris environment and measures that can be taken to control its growth. Major Contents: Orbital Debris research is divided into the following five broad efforts. Each area of research contains specific information as follows: 1) Modeling - NASA scientists continue to develop and upgrade orbital debris models to describe and characterize the current and future debris environment. Evolutionary and engineering models are described in detail. Downloadable items include a document in PDF format and executable software. 2) Measurements - Measurements of near-Earth orbital debris are accomplished by conducting ground-based and space-based observations of the orbital debris environment. The data from these sources provide validation of the environment models and identify the presence of new sources. Radar, optical and surface examinations are described. External links to related topics are provided. 3) Protection - Orbital debris protection involves conducting hypervelocity impact measurements to assess the risk presented by orbital debris to operating spacecraft and developing new materials and new designs to provide better protection from the environment with less weight penalty. The data from this work provides the link between the environment defined by the models and the risk presented by that environment to operating spacecraft and provides recommendations on design and operations procedures to reduce the risk as

  10. Independent Orbiter Assessment (IOA): Analysis of the orbital maneuvering system

    NASA Technical Reports Server (NTRS)

    Prust, C. D.; Paul, D. J.; Burkemper, V. J.

    1987-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results for the Orbital Maneuvering System (OMS) hardware are documented. The OMS provides the thrust to perform orbit insertion, orbit circularization, orbit transfer, rendezvous, and deorbit. The OMS is housed in two independent pods located one on each side of the tail and consists of the following subsystems: Helium Pressurization; Propellant Storage and Distribution; Orbital Maneuvering Engine; and Electrical Power Distribution and Control. The IOA analysis process utilized available OMS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluted and analyzed for possible failure modes and effects. Criticality was asigned based upon the severity of the effect for each failure mode.

  11. Advanced space system for geostationary orbit surveillance

    NASA Astrophysics Data System (ADS)

    Klimenko, N. N.; Nazarov, A. E.

    2016-12-01

    The structure and orbital configuration of the advanced space system for geostationary orbit surveillance, as well as possible approaches to the development of the satellite bus and payload for the geostationary orbit surveillance, are considered.

  12. Thirteenth satellite of Jupiter. [orbit determination

    NASA Technical Reports Server (NTRS)

    Kowal, C. T.; Aksnes, K.; Marsden, B. G.; Roemer, E.

    1975-01-01

    The discovery, observations, and attempts to determine the orbit of Jupiter XIII are described. It is found that the orbit is very similar to the orbits of Jupiter VI, VII, and X. An ephemeris is provided for the 1975 opposition.

  13. Orbiter Crew Compartment Integration-Stowage

    NASA Technical Reports Server (NTRS)

    Morgan, L. Gary

    2007-01-01

    This viewgraph presentation describes the Orbiter Crew Compartment Integration (CCI) stowage. The evolution of orbiter crew compartment stowage volume is also described, along with photographs presented of the on-orbit volume stowage capacity.

  14. Computed tomography of orbital-facial neurofibromatosis

    SciTech Connect

    Zimmerman, R.A.; Bilaniuk, L.T.; Metzger, R.A.; Grossman, R.I.; Schut, L.; Bruce, D.A.

    1983-01-01

    Twenty-four patients with orbital-facial manifestations of neurofibromations were examined by computed tomography. Delineation of the extent of the disease, and differentiation of the disease processes (orbital tumor, osseous orbital dysplasia, plexiform neurofibromatosis, and buphthalmos) was possible.

  15. Reactionless orbital propulsion using tether deployment

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    1990-01-01

    Examples of tether propulsion in orbit without the use of reaction mass are discussed. These include (1) using tether extension to reposition a satellite in orbit without fuel expenditure by extending a mass on the end of the tether; (2) using a tether for eccentricity pumping to add energy to the orbit for boosting and orbital transfer; and (3) length modulation of a spinning tether to transfer angular momentum between the orbit and tether spin, thus allowing changes in orbital angular momentum.

  16. Reactionless orbital propulsion using tether deployment

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    1990-01-01

    Examples of tether propulsion in orbit without the use of reaction mass are discussed. These include (1) using tether extension to reposition a satellite in orbit without fuel expenditure by extending a mass on the end of the tether; (2) using a tether for eccentricity pumping to add energy to the orbit for boosting and orbital transfer; and (3) length modulation of a spinning tether to transfer angular momentum between the orbit and tether spin, thus allowing changes in orbital angular momentum.

  17. Two stage to orbit design

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A preliminary design of a two-stage to orbit vehicle was conducted with the requirements to carry a 10,000 pound payload into a 300 mile low-earth orbit using an airbreathing first stage, and to take off and land unassisted on a 15,000 foot runway. The goal of the design analysis was to produce the most efficient vehicle in size and weight which could accomplish the mission requirements. Initial parametric analysis indicated that the weight of the orbiter and the transonic performance of the system were the two parameters that had the largest impact on the design. The resulting system uses a turbofan ramjet powered first stage to propel a scramjet and rocket powered orbiter to the stage point of Mach 6 to 6.5 at an altitude of 90,000 ft.

  18. Real and Hybrid Atomic Orbitals.

    ERIC Educational Resources Information Center

    Cook, D. B.; Fowler, P. W.

    1981-01-01

    Demonstrates that the Schrodinger equation for the hydrogenlike atom separates in both spheroconal and prolate spheroidal coordinates and that these separations provide a sound theoretical basis for the real and hybrid atomic orbitals. (Author/SK)

  19. How to Orbit the Earth.

    ERIC Educational Resources Information Center

    Quimby, Donald J.

    1984-01-01

    Discusses the geometry, algebra, and logic involved in the solution of a "Mindbenders" problem in "Discover" magazine and applies it to calculations of satellite orbital velocity. Extends the solution of this probe to other applications of falling objects. (JM)

  20. Mars Reconnaissance Orbiter Taking Shape

    NASA Image and Video Library

    2004-08-09

    Lockheed Martin Space Systems engineer Terry Kampmann left and lead technician Jack Farmerie work on assembly and test of NASA Mars Reconnaissance Orbiter spacecraft bus in a cleanroom at the company Denver facility.

  1. Orbital fractures: role of imaging.

    PubMed

    Caranci, Ferdinando; Cicala, Domenico; Cappabianca, Salvatore; Briganti, Francesco; Brunese, Luca; Fonio, Paolo

    2012-10-01

    The orbit may be injured directly or indirectly. Blunt and penetrating trauma occurs with equal frequency. Soft tissue swelling often obscures direct clinical evaluation of the globe, limits ocular motion, and may limit clinical assessment of vision. Plain film radiographs of the orbits and sinuses are rarely used for diagnosis in orbital trauma. Computed tomography is considered the imaging modality of choice in this circumstance, as it is deemed to be the most accurate method in detecting fractures. The protocol is based on obtaining thin-section axial scans and multiplanar reformatted images, both are useful tools to guide treatment. Orbital fractures are not considered an ophthalmologic emergency unless there is visual impairment or globe injury. Surgical repair is indicated for patients who have persistent diplopia or cosmetic concerns (enophthalmos) and generaly is not performed until swelling subsides 7-10 days after injury. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. ARTEMIS Maneuvers into Lunar Orbit

    NASA Image and Video Library

    This animation visualizes the maneuvers required to move the ARTEMIS spacecraft from their kidney-shaped paths on each side of the moon to orbiting the moon. It took one and a half years, over 90 o...

  3. Cost Per Pound From Orbit

    NASA Technical Reports Server (NTRS)

    Merriam, M. L.

    2002-01-01

    Traditional studies of Reusable Launch Vehicle (RLV) designs have focused on designs that are completely reusable except for the fuel. This may not be realistic with current technology . An alternate approach is to look at partially reusable launch vehicles. This raises the question of which parts should be reused and which parts should be expendable. One approach is to consider the cost/pound of returning these parts from orbit. With the shuttle, this cost is about three times the cost/pound of launching payload into orbit. A subtle corollary is that RLVs are much less practical for higher orbits, such as the one on which the International Space Station resides, than they are for low earth orbits.

  4. Orbital Maneuvering system design evolution

    NASA Technical Reports Server (NTRS)

    Gibson, C.; Humphries, C.

    1985-01-01

    Preliminary design considerations and changes made in the baseline space shuttle orbital maneuvering system (OMS) to reduce cost and weight are detailed. The definition of initial subsystem requirements, trade studies, and design approaches are considered. Design features of the engine, its injector, combustion chamber, nozzle extension and bipropellant valve are illustrated and discussed. The current OMS consists of two identical pods that use nitrogen tetroxide (NTO) and monomethylhydrazine (MMH) propellants to provide 1000 ft/sec of delta velocity for a payload of 65,000 pounds. Major systems are pressurant gas storage and control, propellant storage supply and quantity measurement, and the rocket engine, which includes a bipropellant valve, an injector/thrust chamber, and a nozzle. The subsystem provides orbit insertion, circularization, and on orbit and deorbit capability for the shuttle orbiter.

  5. Visualization of Molecular Orbitals: Formaldehyde

    ERIC Educational Resources Information Center

    Olcott, Richard J.

    1972-01-01

    Describes a computer program that plots a solid" representation of molecular orbital charge density which can be used to analyze wave functions of molecules. Illustrated with diagrams for formaldehyde. (AL)

  6. The orbit of Pluto's satellite

    NASA Technical Reports Server (NTRS)

    Tholen, D. J.

    1985-01-01

    Nineteen speckle interferometric observations of the Pluto system have been used to improve the determination of the orbital elements for Pluto's satellite. Calibration uncertainties appear to be the dominant source of error, but the observation of a partial occultation of the satellite by Pluto has been used to constrain the orbit solution. The orbital period is found to be in excellent agreement with the rotational period of the planet, reinforcing the belief that the system is completely tidally evolved. The orbital radius and period imply a total mass for the system of 6.8 + or - 0.5 x 10 to the -9th solar masses. Density constraints place an upper limit of 3615 + or - 90 km on the diameter of Pluto, while observations of the first mutual events establish a crude lower limit of about 2800 km.

  7. Real and Hybrid Atomic Orbitals.

    ERIC Educational Resources Information Center

    Cook, D. B.; Fowler, P. W.

    1981-01-01

    Demonstrates that the Schrodinger equation for the hydrogenlike atom separates in both spheroconal and prolate spheroidal coordinates and that these separations provide a sound theoretical basis for the real and hybrid atomic orbitals. (Author/SK)

  8. Aqua satellite orbiting the Earth

    NASA Image and Video Library

    This animation shows the Aqua satellite orbiting the Earth on August 27, 2005 by revealing MODIS true-color imagery for that day. This animation is on a cartesian map projection, so the satellite w...

  9. How to Orbit the Earth.

    ERIC Educational Resources Information Center

    Quimby, Donald J.

    1984-01-01

    Discusses the geometry, algebra, and logic involved in the solution of a "Mindbenders" problem in "Discover" magazine and applies it to calculations of satellite orbital velocity. Extends the solution of this probe to other applications of falling objects. (JM)

  10. NASA Orbital Debris Baseline Populations

    NASA Technical Reports Server (NTRS)

    Krisko, Paula H.; Vavrin, A. B.

    2013-01-01

    The NASA Orbital Debris Program Office has created high fidelity populations of the debris environment. The populations include objects of 1 cm and larger in Low Earth Orbit through Geosynchronous Transfer Orbit. They were designed for the purpose of assisting debris researchers and sensor developers in planning and testing. This environment is derived directly from the newest ORDEM model populations which include a background derived from LEGEND, as well as specific events such as the Chinese ASAT test, the Iridium 33/Cosmos 2251 accidental collision, the RORSAT sodium-potassium droplet releases, and other miscellaneous events. It is the most realistic ODPO debris population to date. In this paper we present the populations in chart form. We describe derivations of the background population and the specific populations added on. We validate our 1 cm and larger Low Earth Orbit population against SSN, Haystack, and HAX radar measurements.

  11. Ballistic mode Mercury orbiter missions.

    NASA Technical Reports Server (NTRS)

    Hollenbeck, G. R.

    1973-01-01

    The MVM'73 Mercury flyby mission will initiate exploration of this unique planet. No firm plans for follow-on investigations have materialized due to the difficult performance requirements of the next logical step, an orbiter mission. Previous investigations of ballistic mode flight opportunities have indicated requirements for a Saturn V class launch vehicle. Consequently, most recent effort has been oriented to use of solar electric propulsion. More comprehensive study of the ballistic flight mode utilizing Venus gravity-assist has resulted in identification of timely high-performance mission opportunities compatible with programmed launch vehicles and conventional spacecraft propulsion technologies. A likely candidate for an initial orbiter mission is a 1980 opportunity which offers net orbiter spacecraft mass of about 435 kg with the Titan IIIE/Centaur launch vehicle and single stage solid propulsion for orbit insertion.

  12. Visualization of Molecular Orbitals: Formaldehyde

    ERIC Educational Resources Information Center

    Olcott, Richard J.

    1972-01-01

    Describes a computer program that plots a solid" representation of molecular orbital charge density which can be used to analyze wave functions of molecules. Illustrated with diagrams for formaldehyde. (AL)

  13. A Case of Orbital Histoplasmosis.

    PubMed

    Krakauer, Mark; Prendes, Mark Armando; Wilkes, Byron; Lee, Hui Bae Harold; Fraig, Mostafa; Nunery, William R

    2016-01-01

    Histoplasma capsulatum var capsulatum is a dimorphic fungus endemic to the Ohio and Mississippi River Valleys of the United States. In this case report, a 33-year-old woman who presented with a right orbital mass causing progressive vision loss, diplopia, and facial swelling is described. Lateral orbitotomy with lateral orbital wall bone flap was performed for excisional biopsy of the lesion. The 1.5 × 1.8 × 2.3 cm cicatricial mass demonstrated a granulomatous lesion with necrosis and positive staining consistent with Histoplasma capsulatum var capsulatum infection. To the authors' knowledge, this is the first case of orbital histoplasmosis to be reported in the United States and the first case worldwide of orbital histoplasmosis due to Histoplasma capsulatum var capsulatum.

  14. Lunar orbital mass spectrometer experiment

    NASA Technical Reports Server (NTRS)

    Lord, W. P.

    1971-01-01

    The design, development, manufacture, test and calibration of five lunar orbital mass spectrometers with the four associated ground support equipment test sets are discussed. A mass spectrometer was installed in the Apollo 15 and one in the Apollo 16 Scientific Instrument Module within the Service Module. The Apollo 15 mass spectrometer was operated with collection of 38 hours of mass spectra data during lunar orbit and 50 hours of data were collected during transearth coast. The Apollo 16 mass spectrometer was operated with collection of 76 hours of mass spectra data during lunar orbit. However, the Apollo 16 mass spectrometer was ejected into lunar orbit upon malfunction of spacecraft boom system just prior to transearth insection and no transearth coast data was possible.

  15. Lunar Orbiter I - Moon & Earth

    NASA Technical Reports Server (NTRS)

    1966-01-01

    First view of the earth and moon from space. Published in: Spaceflight Revolution: Langley Research Center From Sputnik to Apollo, by James R. Hansen. NASA History Series. NASA SP ; 4308. p ii. Caption: 'The picture of the century was this first view of the earth from space. Lunar Orbiter I took the photo on 23 August 1966 on its 16th orbit just before it passed behind the moon. The photo also provided a spectacular dimensional view of the lunar surface.'

  16. Orbits in a logarithmic potential

    SciTech Connect

    Hooverman, R. H.

    2014-04-15

    The characteristics of charged particle orbits in the logarithmic electrostatic potential field surrounding a straight conducting wire at a fixed potential are investigated. The equations of motion of an electron in a logarithmic potential are derived, the limiting cases are considered, and the results of numerical integration of the equations of motion are presented along with sketches of a few representative orbits. (C.E.S.)

  17. Orbital ATK CRS-7 Rollout

    NASA Image and Video Library

    2017-04-17

    A United Launch Alliance Atlas V rocket, with the Orbital ATK Cygnus pressurized cargo module, arrives at the pad at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Orbital ATK's seventh commercial resupply services mission, CRS-7, is scheduled to launch to the International Space Station on April 18, 2017. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station. Liftoff is scheduled for 11:11 a.m. EDT.

  18. Orbit Prediction Tool for Different Classes of Space Debris Orbits

    NASA Astrophysics Data System (ADS)

    Wnuk, Edwin; Wytrzyszczak, Iwona; Golembiewska, Justyna; Klinkrad, Heiner

    There are two aspects of the orbital evolution of space debris: the long-term evolution and the short-term prediction of individual object orbits. In the case of the long-term evolution (years or tens of years time span) general characteristics (e.g. total number of objects, spa-tial distribution and density) of a future space environment are predicted with the use of a relatively simple theory of motion for statistical analysis of future orbits of a large number of objects -a cloud of particles". In the short-term orbital evolution of space debris objects, as considered in this paper, future positions and velocities of individual objects are calculated for a few days or a few weeks time span. A much more sophisticated theory of satellite motion is applied in this case. The paper presents the orbital prediction tool that uses an analytical and semi-analytical theories of satellite motion. The force model includes all important perturbing factors: geopotential effects with arbitrary degree and order spherical harmonic coefficients taken into account, luni-solar attractions, solar radiation pressure and atmospheric drag. The analytical theory of motion is of the second order and is not sensitive to singularities for small eccentricities and small inclinations. A new algorithm for the transformation between mean and osculating elements for the second order theory is applied. Predicted positions of a satel-lite on a given level of accuracy are calculated only with the use of terms that essentially influence on predicted satellite orbit, all other terms are omitted. The number of terms in for-mulas for perturbations, and thus complexity of the theory, depends on the defined level of accuracy and the type of orbit. In practice, we create a dynamical model for a given class of satellite orbit. Geopotential and luni-solar perturbations are calculated in the two following steps. In the first step, values of secular terms and all amplitudes of periodic terms are calculated

  19. Low Earth orbit communications satellite

    NASA Technical Reports Server (NTRS)

    Moroney, D.; Lashbrook, D.; Mckibben, B.; Gardener, N.; Rivers, T.; Nottingham, G.; Golden, B.; Barfield, B.; Bruening, J.; Wood, D.

    1992-01-01

    A current thrust in satellite communication systems considers a low-Earth orbiting constellations of satellites for continuous global coverage. Conceptual design studies have been done at the time of this design project by LORAL Aerospace Corporation under the program name GLOBALSTAR and by Motorola under their IRIDIUM program. This design project concentrates on the spacecraft design of the GLOBALSTAR low-Earth orbiting communication system. Overview information on the program was gained through the Federal Communications Commission licensing request. The GLOBALSTAR system consists of 48 operational satellites positioned in a Walker Delta pattern providing global coverage and redundancy. The operational orbit is 1389 km (750 nmi) altitude with eight planes of six satellites each. The orbital planes are spaced 45 deg., and the spacecraft are separated by 60 deg. within the plane. A Delta 2 launch vehicle is used to carry six spacecraft for orbit establishment. Once in orbit, the spacecraft will utilize code-division multiple access (spread spectrum modulation) for digital relay, voice, and radio determination satellite services (RDSS) yielding position determination with accuracy up to 200 meters.

  20. Precision Orbit Determination for the Lunar Reconnaissance Orbiter

    NASA Astrophysics Data System (ADS)

    Lemoine, Frank; Rowlands, David; McGarry, Jan; Neumann, Gregory; Chinn, Douglas; Mazarico, Erwan; Torrence, Mark

    The U.S. Lunar Reconnaissance Orbiter (LRO) mission will be launched in October 2008, and will carry out a detailed mapping of the Moon using a science payload of multiple instruments, including the Lunar Orbiter Laser Altimeter (LOLA), and the Lunar Reconnaissance Orbiter Camera (LROC) (Chin, 2007). One of the primary goals of the LRO mission is develop a geodetic grid for the planet. A subsidiary goal is the improvement of the lunar gravity field. The environment for POD on LRO is especially challenging. The spacecraft will orbit the Moon at a mean altitude of 50 km, and the expected error from the Lunar Prospector series of gravity models (to degree 100 or to degree 150) can be expected to be hundreds of meters. LRO will be tracked by S Band Doppler from White Sands, New Mexico, and Dongara, Australia, as well as by one-way laser ranging from Satellite Laser Ranging (SLR) tracking stations on the Earth. However, unlike the Japanese lunar mission SELENE (Kaguya), no direct tracking will be available while the spacecraft is over the lunar farside. We review the status of orbit modelling for LRO, for both the geopotential modelling and the nonconservative force models, as well as anticipated improvements. We discuss the modelling for the one-way laser ranging observable, and how the data from the one-way laser ranging (LR) system will be acquired from selected stations of the global stations of the SLR network. We discuss the orbit determination strategies which we expect to implement on this mission, including the use of altimeter crossovers from the LOLA instrument to supplement the Earth-based tracking and we review the projected orbit determination accuracies that will be attainable.

  1. Mafic sill/dykes intruding into late Maastrichtian-early Paleocene calciclastic units, NE-Turkey: Petrographical and geochemical features of latest magmatic activity before collision in the eastern Sakarya zone

    NASA Astrophysics Data System (ADS)

    Aydin, Faruk; Oǧuz, Simge; Karsli, Orhan; Kandemir, Raif; Şen, Cüneyt; Uysal, İbrahim

    2017-04-01

    We present here new petrographical, mineralogical and whole-rock geochemical data for mafic sill/dykes intruding into late Maastrichtian-early Paleocene calciclastic units in the Düzköy (Trabzon) and Cankurtaran (Artvin) areas (NE Turkey) of the eastern Sakarya zone (ESZ) in order to decipher the latest magmatic activity in the final stage of subduction-related magmatism of the ESZ. U-Pb zircon dating for the mafic sill/dykes in the region yielded ages varying from 83.6 to 78.5Ma (i.e. Early Campanian). Mafic sill/dykes consist of mostly basalts and lesser basaltic-andesites with komatiitic basalts. Most of the dyke samples display aphyric to porphyritic texture with phenocrysts of plagioclase (mostly replaced by calcite), clinopyroxene (partly uralized), olivine (almost serpentinized), and amphibole (partly chloritized). Based on the MgO, Nb and Zr contents with Nb/Y ratio, the mafic dykes from Düzköy area are mainly classified as two subgroups (basalts and basaltic andesites) while those of Cankurtaran can be divided into three different groups (low- and high-Nb normal basalts and komatitic basalts). Düzköy basaltic dykes have higher MgO (3.8-7.8%) and lower Nb (3-4ppm) and Zr (53-62ppm) contents with Nb/Y ratio (˜0.2) than those of Düzköy basaltic-andesitic dykes (MgO: ˜1.8%, Nb: 6-15ppm, Zr: 106-145ppm, Nb/Y: 0.3-0.6). On the other hand, Cankurtaran mafic sill/dykes have relatively high MgO contents (˜4-20%). These sill/dykes with 15-20% of MgO and <1% TiO2 contents are called as komatiitic basalt which has relatively low K2O (<1%), Nb (˜1ppm), Zr (23-26ppm) and Y (8ppm) contents with Nb/Y ratio (˜0.1-0.2). However, normal basalts from Cankurtaran have quite lower MgO contents (˜4-9%) than that of the komatiitic basalt. Also, they can be divided into two subgroups in terms of MgO (5.7-8.7% for group 1 and 4.0-4.4% for group 2), Nb (3-14ppm for group 1 and 19-21ppm for group 2), Zr (94-111ppm for group 1 and 125-140ppm for group 2) contents, and Nb

  2. Space Tourism: Orbital Debris Considerations

    NASA Astrophysics Data System (ADS)

    Mahmoudian, N.; Shajiee, S.; Moghani, T.; Bahrami, M.

    2002-01-01

    Space activities after a phase of research and development, political competition and national prestige have entered an era of real commercialization. Remote sensing, earth observation, and communication are among the areas in which this growing industry is facing competition and declining government money. A project like International Space Station, which draws from public money, has not only opened a window of real multinational cooperation, but also changed space travel from a mere fantasy into a real world activity. Besides research activities for sending man to moon and Mars and other outer planets, space travel has attracted a considerable attention in recent years in the form of space tourism. Four countries from space fairing nations are actively involved in the development of space tourism. Even, nations which are either in early stages of space technology development or just beginning their space activities, have high ambitions in this area. This is worth noting considering their limited resources. At present, trips to space are available, but limited and expensive. To move beyond this point to generally available trips to orbit and week long stays in LEO, in orbital hotels, some of the required basic transportations, living requirements, and technological developments required for long stay in orbit are already underway. For tourism to develop to a real everyday business, not only the price has to come down to meaningful levels, but also safety considerations should be fully developed to attract travelers' trust. A serious hazard to space activities in general and space tourism in particular is space debris in earth orbit. Orbiting debris are man-made objects left over by space operations, hazardous to space missions. Since the higher density of debris population occurs in low earth orbit, which is also the same orbit of interest to space tourism, a careful attention should be paid to the effect of debris on tourism activities. In this study, after a

  3. Orbital order from the on-site orbital attraction

    NASA Astrophysics Data System (ADS)

    Khodas, M.; Chubukov, A. V.

    2016-09-01

    We study the model of Fe-based superconductors with intraorbital attraction, designed to favor a spontaneous orbital polarization. Previous studies of this model within the two-orbital approximation indicated that the leading instability is toward s -wave superconductivity and the subleading one is toward anti-ferro-orbital order, which breaks the translational symmetry of the crystal. The two-orbital approximation is, however, not consistent with the Fermi surface geometry of Fe superconductors, as it yields the wrong position of one of the hole pockets. Here we analyze the model with the same interaction but with realistic Fermi surface geometry (two hole pockets at the center of the Brillouin zone and two electron pockets at its boundary). We apply the parquet renormalization-group (pRG) technique to detect the leading instability upon the lowering of the temperature. We argue that the pRG analysis strongly favors a q =0 orbital order, which in the band basis is a d -wave Pomeranchuk order.

  4. Impact of Dynamics Orbit Parameters of Different Reference Epoch on Predicted Orbit Accuracy

    NASA Astrophysics Data System (ADS)

    Zhang, Rui

    2017-04-01

    The dynamics orbit parameters of any epoch in the observed arc can be calculated by the observed orbit. Then the orbit outside the observed arc can be calculated by the dynamics orbit parameters of this epoch. Because of the impact of the observed orbit solving strategies and the orbit integration error, the dynamics orbit parameters in different epoch directly affects the accuracy of predicted orbit. In this paper, the different schemes that whether to join the velocity breaks parameters were used to calculate the observed orbit of GPS, GLONASS, BDS and GALILEO. And in the observed arc, the dynamics orbit parameters of every 6 hours were used to calculate the 24-hour predicted orbit outside the observed arc. The results show that when the velocity breaks parameters are calculated in the observed orbit, the dynamics orbit parameters of different epoch directly affects the accuracy of predicted orbit.

  5. The 2009 Mars Telecommunications Orbiter

    NASA Technical Reports Server (NTRS)

    Wilson, G. R.; DePaula, R.; Diehl, R. E.; Edwards, C. D.; Fitzgerald, R. J.; Franklin, S. F.; Kerridge, S. A.; Komarek, T. A.; Noreen, G. K.

    2004-01-01

    The first spacecraft with a primary function of providing communication links while orbiting a foreign planet has begun development for a launch in 2009. NASA's Mars Telecommunications Orbiter would use three radio bands to magnify the benefits of other future Mars missions and enable some types of missions otherwise impractical. It would serve as the Mars hub for a growing interplanetary Internet. And it would pioneer the use of planet-to-planet laser communications to demonstrate the possibility for even greater networking capabilities in the future. With Mars Telecommunications Orbiter overhead in the martian sky, the Mars Science Laboratory rover scheduled to follow the orbiter to Mars by about a month could send to Earth more than 100 times as much data per day as it could otherwise send. The orbiter will be designed for the capability of relaying up to 15 gigabits per day from the rover, equivalent to more than three full compact discs each day. The same benefits would accrue to other future major Mars missions from any nation.

  6. Featured Image: Globular Cluster Orbits

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2017-04-01

    This figure (click for the full view) shows the meridional galactic orbits of 12 globular clusters that orbit the Milky Way. The recent release of stellar parallax data from Gaia allowed a team of scientists at Dartmouth College to improve measurements of a number of galactic globular clusters very old clusters of stars that can either orbit within the galactic disk and bulge or more distantly in the galactic halo. In a recent publication led by Erin OMalley, the team presents their findings and combines their new measurements for the clusters with proper motions from past studies to calculate the orbits that these globulars take. These calculations show us whether the clusters reside in the galactic disk and bulge (as only NGC 104 does in the sample shown here, since its orbit is confined to 8 kpc radially and 4 kpc vertically of the galactic center), or if they are halo clusters. To learn more about the authors work, you can check out the paper below!CitationErin M. OMalley et al 2017 ApJ 838 162. doi:10.3847/1538-4357/aa6574

  7. Tumor pathology of the orbit.

    PubMed

    Héran, F; Bergès, O; Blustajn, J; Boucenna, M; Charbonneau, F; Koskas, P; Lafitte, F; Nau, E; Roux, P; Sadik, J C; Savatovsky, J; Williams, M

    2014-10-01

    The term orbital tumor covers a wide range of benign and malignant diseases affecting specific component of the orbit or developing in contact with them. They are found incidentally or may be investigated as part of the assessment of a systemic disorder or because of orbital signs (exophthalmos, pain, etc.). Computed tomography, MRI and Color Doppler Ultrasound (CDU), play a varying role depending on the clinical presentation and the disease being investigated. This article reflects long experience in a reference center but does not claim to be exhaustive. We have chosen to consider these tumors from the perspective of their usual presentation, emphasizing the most common causes and suggestive radiological and clinical presentations (progressive or sudden-onset exophthalmos, children or adults, lacrimal gland lesions, periorbital lesions and enophthalmos). We will describe in particular muscle involvement (thyrotoxicosis and tumors), vascular lesions (cavernous sinus hemangioma, orbital varix, cystic lymphangioma), childhood lesions and orbital hematomas. We offer straightforward useful protocols for simple investigation and differential diagnosis. Readers who wish to go further to extend their knowledge in this fascinating area can refer to the references in the bibliography.

  8. Sampling characteristics of satellite orbits

    NASA Technical Reports Server (NTRS)

    Wunsch, Carl

    1989-01-01

    The irregular space-time sampling of any finite region by an orbiting satellite raises difficult questions as to which frequencies and wavenumbers can be determined and which will alias into others. Conventional sampling theorems must be extended to account for both irregular data distributions and observational noise - the sampling irregularity making the system much more susceptible to noise than in regularly sampled cases. The problem is formulated here in terms of least-squares and applied to spacecraft in 10-day and 17-day repeating orbits. The 'diamond-pattern' laid down spatially in such repeating orbits means that either repeat period adequately samples the spatial variables, but the slow overall temporal coverage in the 17-day pattern leads to much greater uncertainty than in the shorter repeat cycle. The result is not definitive and it is not concluded that a 10-day orbit repeat is the most appropriate one. A major conclusion, however, is that different orbital choices have potentially quite different sampling characteristics which need to be analyzed in terms of the spectral characteristics of the moving sea surface.

  9. THE ORBITS OF THE OUTER URANIAN SATELLITES

    SciTech Connect

    Brozovic, M.; Jacobson, R. A.

    2009-04-15

    We report on the numerically integrated orbits for the nine outer Uranian satellites. The orbits are calculated based on fits to the astrometric observations for the period from 1984 to 2006. The results include the state vectors, post-fit residuals, and mean orbital elements. We also assess the accuracy of the orbital fits and discuss the need for future measurements.

  10. An Analytical Satellite Orbit Predictor (ASOP)

    NASA Technical Reports Server (NTRS)

    Starke, S. E.

    1977-01-01

    The documentation and user's guide for the Analytical Satellite Orbit Predictor (ASOP) computer program is presented. The ASOP is based on mathematical methods that represent a new state-of-the-art for rapid orbit computation techniques. It is intended to be used for computation of near-earth orbits including those of the shuttle/orbiter and its payloads.

  11. The Eccentric Behavior of Nearly Frozen Orbits

    NASA Technical Reports Server (NTRS)

    Sweetser, Theodore H.; Vincent, Mark A.

    2013-01-01

    Frozen orbits are orbits which have only short-period changes in their mean eccentricity and argument of periapse, so that they basically keep a fixed orientation within their plane of motion. Nearly frozen orbits are those whose eccentricity and argument of periapse have values close to those of a frozen orbit. We call them "nearly" frozen because their eccentricity vector (a vector whose polar coordinates are eccentricity and argument of periapse) will stay within a bounded distance from the frozen orbit eccentricity vector, circulating around it over time. For highly inclined orbits around the Earth, this distance is effectively constant over time. Furthermore, frozen orbit eccentricity values are low enough that these orbits are essentially eccentric (i.e., off center) circles, so that nearly frozen orbits around Earth are bounded above and below by frozen orbits.

  12. Virtual Surgical Planning for Orbital Reconstruction.

    PubMed

    Susarla, Srinivas M; Duncan, Katherine; Mahoney, Nicholas R; Merbs, Shannath L; Grant, Michael P

    2015-01-01

    The advent of computer-assisted technology has revolutionized planning for complex craniofacial operations, including orbital reconstruction. Orbital reconstruction is ideally suited for virtual planning, as it allows the surgeon to assess the bony anatomy and critical neurovascular structures within the orbit, and plan osteotomies, fracture reductions, and orbital implant placement with efficiency and predictability. In this article, we review the use of virtual surgical planning for orbital decompression, posttraumatic midface reconstruction, reconstruction of a two-wall orbital defect, and reconstruction of a large orbital floor defect with a custom implant. The surgeon managing orbital pathology and posttraumatic orbital deformities can benefit immensely from utilizing virtual planning for various types of orbital pathology.

  13. Virtual Surgical Planning for Orbital Reconstruction

    PubMed Central

    Susarla, Srinivas M.; Duncan, Katherine; Mahoney, Nicholas R.; Merbs, Shannath L.; Grant, Michael P.

    2015-01-01

    The advent of computer-assisted technology has revolutionized planning for complex craniofacial operations, including orbital reconstruction. Orbital reconstruction is ideally suited for virtual planning, as it allows the surgeon to assess the bony anatomy and critical neurovascular structures within the orbit, and plan osteotomies, fracture reductions, and orbital implant placement with efficiency and predictability. In this article, we review the use of virtual surgical planning for orbital decompression, posttraumatic midface reconstruction, reconstruction of a two-wall orbital defect, and reconstruction of a large orbital floor defect with a custom implant. The surgeon managing orbital pathology and posttraumatic orbital deformities can benefit immensely from utilizing virtual planning for various types of orbital pathology. PMID:26692714

  14. Late Cretaceous marine transgressions in Ecuador and northern Peru: A refined stratigraphic framework

    NASA Astrophysics Data System (ADS)

    Jaillard, Etienne; Bengtson, Peter; Dhondt, Annie V.

    2005-08-01

    Study of ammonites and bivalves along selected sections on the Andean margin of northern Peru and Ecuador has made it possible to recognize correlatable marine transgressions and propose a refined stratigraphic framework for the Upper Cretaceous of the region. Six maximum flooding events are recognized: latest Turonian-early Coniacian (major event), late Coniacian-early Santonian, early Campanian, mid Campanian-early late Campanian (major event), early Maastrichtian (major event), and terminal early Maastrichtian. Most of these events can be correlated with global eustatic sea level rises, but their relative manifestations indicate that the Andean margin already was being deformed by the late Cretaceous 'Peruvian' tectonic events. The onset of fine-grained clastic sedimentation in the Oriente and East Peruvian basins in the mid Turonian-earliest Coniacian is taken as the first event of the 'Peruvian' phase. The Campanian regional transgression in the Peruvian-Ecuadorian forearc zones concealed the 'Peruvian' deformational event. The latter caused a paleogeographic upheaval, as indicated by the subsequent development of a NNE-trending forearc basin, which extended from Paita in northwestern Peru to northern Ecuador. In the forearc zones, only short-lived transgressions are recorded in the late Campanian and early Maastrichtian as a result of nearly continuous tectonic activity. This activity culminated with a significant tectonic event in the late Maastrichtian that caused a widespread hiatus.

  15. Orbit of 1976 AA. [asteroid

    NASA Technical Reports Server (NTRS)

    Marsden, B. G.; Williams, J. G.

    1977-01-01

    The orbit of Asteroid 1976 AA is described, with attention given to calculations of its period and its distance from earth, both of which could be accurately and quickly determined by measuring the minor planet's position over wide ranges of hour angle on one to three nights. The geometry of the asteroid's orbit is compared to that of earth's orbit, and the periodicity of the minor planet's approaches to earth is projected. The motion of 1976 AA over an interval of seven centuries into both past and future is also studied; the possibility of its libration with respect to earth or to Venus is examined. Some data on closest approaches of the asteroid to Mars and Venus, as well as to earth, are given.

  16. Orbiter Atlantis returns to KSC

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Shuttle Carrier Aircraft rolls to a stop with its piggyback cargo -- orbiter Atlantis -- at the Shuttle Landing Facility. In the background is the Vehicle Assembly Building. Atlantis returns home after a 10-month stay in the Palmdale, CA, orbiter processing facility undergoing extensive inspections and modifications. They included several upgrades enabling it to support International Space Station missions, such as adding an external airlock for ISS docking missions and installing thinner, lighter thermal protection blankets for weight reduction which will allow it to haul heavier cargo. The flight from Palmdale included a fueling stop in Ft. Hood, TX, and overnight stay at Ft. Campbell, KY. Atlantis will undergo preparations in the Orbiter Processing Facility at KSC for its planned flight in June 1999.

  17. Summary of Orbital Debris Workshop

    NASA Technical Reports Server (NTRS)

    Kessler, D. J.

    1982-01-01

    An Orbital Debris Workshop was conducted in July 1982. The working groups established were related to measurements of large particles, modeling of large particles, measurements of small particles, spacecraft hazard and shielding requirements, and space object management. The results of the Orbital Debris Workshop reaffirm the need for research to better understand the character of orbital debris, its effects on future spacecraft, and the related requirements for policy. A clear charter is required for this research to receive the necessary support, focus, and coordination. It was recommended that NASA assume the role of lead agency. The first task is to develop an overall plan with both Department of Defense and the North American Aerospace Defense Command participation.

  18. Orbiter Atlantis returns to KSC

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Stairs are rolled to the forward opening of the Shuttle Carrier Aircraft -- with its piggyback cargo, the orbiter Atlantis -- after it rolls to a stop at the Shuttle Landing Facility. Atlantis returns home after a 10-month stay in the Palmdale, CA, orbiter processing facility undergoing extensive inspections and modifications. They included several upgrades enabling it to support International Space Station missions, such as adding an external airlock for ISS docking missions and installing thinner, lighter thermal protection blankets for weight reduction which will allow it to haul heavier cargo. The flight from Palmdale included a fueling stop in Ft. Hood, TX, and overnight stay at Ft. Campbell, KY. Atlantis will undergo preparations in the Orbiter Processing Facility at KSC for its planned flight in June 1999.

  19. The evolution of comet orbits

    NASA Technical Reports Server (NTRS)

    Everhart, E.

    1976-01-01

    The origin of comets and the evolution of their orbits are discussed. Factors considered include: the law of survival of comets against ejection on hyperbolic orbits; short-period comets are not created by single close encounters of near-parabolic comets with Jupiter; observable long-period comets do not evolve into observable short-period comets; unobservable long-period comets with perihelia near Jupiter can evolve into observable short-period comets; long-period comets cannot have been formed or created within the planetary region of the solar system (excluding the effects of stellar perturbations); it is possible that some of the short-period comets could have been formed inside the orbit of Neptune; circularly-restricted three-body problem, and its associated Jacobi integral, are not valid approximations to use in studying origin and evolution of comets.

  20. Oncocytic Adenocarcinoma of the Orbit.

    PubMed

    Harris, Gerald J; Paul, Sean; Hunt, Bryan C

    Oncocytic adenocarcinoma of the orbit is a rare tumor, with 1 case of nonlacrimal sac, nonlacrimal gland origin, and a poor outcome previously reported. An 85-year-old man with a 2-month history of left-sided epiphora, enlarging eyelid nodules, and diplopia in left gaze was found on imaging to have a poorly circumscribed, nodular mass of uniform radiodensity in the inferomedial orbit. Incisional biopsy revealed morphologic and immunohistochemical features of oncocytic adenocarcinoma with origin in the caruncle suspected, and CT of the neck, chest, abdomen, and pelvis showed no metastases or remote primary tumor source. Based on multidisciplinary consensus, orbital exenteration with adjuvant radiation therapy was performed, and there was no evidence of residual or recurrent tumor 2 years after treatment.

  1. Orbital exenteration in periorbital malignancies.

    PubMed

    Roche, Phoebe; Timon, Conrad

    2012-08-01

    Orbital exenteration is a disfiguring procedure most commonly performed for locally advanced or recurrent periorbital malignancies. We performed a retrospective review of 22 patients who underwent orbital exenteration for advanced periorbital malignancy at our institution, by the senior author over a seventeen-year period. Specifically, we have reviewed the tumour histology along with stage at presentation, patient age, history of previous surgical intervention and surgical outcomes. The review highlighted two main groups who required orbital exenteration - patients with recurrent or locally advanced periorbital skin cancers, and patients with malignancy of the sinus. We discuss the presentation and management of the two pathological processes and highlight the importance of aggressive early management of periorbital malignancy with a view to prevention of exenteration and improving survival. Copyright © 2011 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  2. The Challenge of Orbital Debris

    NASA Technical Reports Server (NTRS)

    Matney, Mark

    2012-01-01

    Since the dawn of the Space Age more than 50 years ago, humans have been launching objects into the space environment faster than they have been removed by active means or natural decay. This has led to a proliferation of debris -- derelict satellites, discarded rocket upper stages, and pieces from satellite breakups -- in Earth orbit, especially in well-used orbital regimes. This talk will summarize the current knowledge of the debris environment and describe plans to address the challenges orbital debris raises for the future usability of near-Earth space. The talk will be structured around 4 categories: Measurements, Modeling, Shielding, and Mitigation. This will include discussions of the long-term prognosis of debris growth (i.e., the "Kessler Syndrome") as well as plans for active debris removal.

  3. Management of the orbital environment

    NASA Technical Reports Server (NTRS)

    Loftus, Joseph P., Jr.; Kessler, Donald J.; Anz-Meador, Phillip D.

    1991-01-01

    Data regarding orbital debris are presented to shed light on the requirements of environmental management in space, and strategies are given for active intervention and operational strategies. Debris are generated by inadvertent explosions of upper stages, intentional military explosions, and collisional breakups. Design and operation practices are set forth for minimizing debris generation and removing useless debris from orbit in the low-earth and geosynchronous orbits. Self-disposal options include propulsive maneuvers, drag-augmentation devices, and tether systems, and the drag devices are described as simple and passive. Active retrieval and disposition are considered, and the difficulty is examined of removing small debris. Active intervention techniques are required since pollution prevention is more effective than remediation for the problems of both earth and space.

  4. Gravity Probe B orbit determination

    NASA Astrophysics Data System (ADS)

    Shestople, P.; Ndili, A.; Hanuschak, G.; Parkinson, B. W.; Small, H.

    2015-11-01

    The Gravity Probe B (GP-B) satellite was equipped with a pair of redundant Global Positioning System (GPS) receivers used to provide navigation solutions for real-time and post-processed orbit determination (OD), as well as to establish the relation between vehicle time and coordinated universal time. The receivers performed better than the real-time position requirement of 100 m rms per axis. Post-processed solutions indicated an rms position error of 2.5 m and an rms velocity error of 2.2 mm s-1. Satellite laser ranging measurements provided independent verification of the GPS-derived GP-B orbit. We discuss the modifications and performance of the Trimble Advance Navigation System Vector III GPS receivers. We describe the GP-B precision orbit and detail the OD methodology, including ephemeris errors and the laser ranging measurements.

  5. LOP - Long-Term Orbit Predictor

    NASA Technical Reports Server (NTRS)

    Kwok, Johnny H.

    1992-01-01

    Long-Term Orbit Preditor (LOP) trajectory-propagation computer program is useful tool in analysis of lifetime of orbiting spacecraft. Suitable for studying planetary-orbit missions with reconnaissance (flyby) and exploratory (mapping) trajectories. Includes sample data for study of drift cycle of geosynchronous station, strategy for radar mapping of Venus, frozen orbit about Mars, and orbit characterized by repeating ground trace. Executed faster than such programs based on Cowell's method. Written in FORTRAN 77.

  6. Radio frequency interference at the geostationary orbit

    NASA Technical Reports Server (NTRS)

    Sue, M. K.

    1981-01-01

    Growing demands on the frequency spectrum have increased the possibility of radio frequency interference (RFI). Various approaches to obtain in orbit RFI data are compared; this comparision indicates that the most practical way to obtain RFI data for a desired orbit (such as a geostationary orbit) is through the extrapolation of in orbit RFI measurements by a low orbit satellite. It is concluded that a coherent RFI program that uses both experimental data and analytical predictions provides accurate RFI data at minimal cost.

  7. Using Mean Orbit Period in Mars Reconnaissance Orbiter Maneuver Design

    NASA Technical Reports Server (NTRS)

    Chung, Min-Kun J.; Menon, Premkumar R.; Wagner, Sean V.; Williams, Jessica L.

    2014-01-01

    Mars Reconnaissance Orbiter (MRO) has provided communication relays for a number of Mars spacecraft. In 2016 MRO is expected to support a relay for NASA's Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) spacecraft. In addition, support may be needed by another mission, ESA's ExoMars EDL Demonstrator Module's (EDM), only 21 days after the InSight coverage. The close proximity of these two events presents a unique challenge to a conventional orbit synchronization maneuver where one deterministic maneuver is executed prior to each relay. Since the two events are close together and the difference in required phasing between InSight and EDM may be up to half an orbit (yielding a large execution error), the downtrack timing error can increase rapidly at the EDM encounter. Thus, a new maneuver strategy that does not require a deterministic maneuver in-between the two events (with only a small statistical cleanup) is proposed in the paper. This proposed strategy rests heavily on the stability of the mean orbital period. The ability to search and set the specified mean period is fundamental in the proposed maneuver design as well as in understanding the scope of the problem. The proposed strategy is explained and its result is used to understand and solve the problem in the flight operations environment.

  8. Assessing Terra Disposal Orbit Candidates from an Orbital Debris Perspective

    NASA Technical Reports Server (NTRS)

    Abraham, Andrew J.; Thompson, Roger C.; Mantziaras, Dimitrios C.

    2016-01-01

    The NASA Terra satellite is reaching the end of its mission life. Because the satellite resides in the 705 km Earth Science Constellation, disposal strategies need to be considered to remove it from this densely populated operational orbit. Of critical importance was the need to examine the future potential risk to other satellite residents of the 705 km constellation due to an unexpected breakup event of the Terra satellite post-disposal. This study quantifies the comparative risk of debris impacts associated with the two leading candidate disposal orbits (701 km vs. 686 km) and characterizes the suitability of each orbit for the purpose of long-term spacecraft disposal. The increase in collision risk to any member of the 705 km Earth Science Constellation is very modest. The long-term, average, total risk (including the ambient background risk) due to a Terra breakup at a disposal of -19 km (i.e., 686 km) relative to the 705 km constellation is 9.7 × 10(exp -6) impacts/day versus 1.0 × 10(exp -5) impacts/day for a disposal of only -4 km (i.e., 701 km). For perspective, note that the nominal space background risk to the 705 km constellation is 9.2 × 10(exp -6) impacts/day which implies a very modest increase in risk (approximately 3% difference between the two cases) due to a Terra breakup in either disposal orbit.

  9. [Primary orbital squamous cell carcinoma].

    PubMed

    Campos Arbulú, Ana L; Sadava, Emmanuel E; Sánchez Ruiz, Alejandro; Fernández Vila, Juan M; Dillon, Horacio S; Mezzadri, Norberto A

    2017-01-01

    Primary orbital squamous cell carcinoma is a rare entity. There is little published literature. We report a case of primary squamous cell carcinoma of the orbital soft tissues. Surgical resection offered the best treatment for the patient. Complete resection of the lesion was achieved. The patient received adjuvant radiotherapy due to the proximity of the lesion to the surgical margins. Surgical treatment is feasible and should be considered as part of the surgeon's arsenal. However, therapeutic decisions must be made on a case-by-case basis.

  10. Orbital Resonances Around Black Holes

    NASA Astrophysics Data System (ADS)

    Brink, Jeandrew; Geyer, Marisa; Hinderer, Tanja

    2015-02-01

    We compute the length and time scales associated with resonant orbits around Kerr black holes for all orbital and spin parameters. Resonance-induced effects are potentially observable when the Event Horizon Telescope resolves the inner structure of Sgr A*, when space-based gravitational wave detectors record phase shifts in the waveform during the resonant passage of a compact object spiraling into the black hole, or in the frequencies of quasiperiodic oscillations for accreting black holes. The onset of geodesic chaos for non-Kerr spacetimes should occur at the resonance locations quantified here.

  11. Energy and the Elliptical Orbit

    NASA Astrophysics Data System (ADS)

    Nettles, Bill

    2009-03-01

    In the January 2007 issue of The Physics Teacher, Prentis, Fulton, Hesse, and Mazzino describe a laboratory exercise in which students use a geometrical analysis inspired by Newton to show that an elliptical orbit and an inverse-square law force go hand in hand. The historical, geometrical, and teamwork aspects of the exercise are useful and important. This paper presents an exercise which uses an energy/angular momentum conservation model for elliptical orbits. This exercise can be done easily by an individual student and on regular notebook-sized paper.

  12. Orbiter electrical equipment utilization baseline

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The baseline for utilization of Orbiter electrical equipment in both electrical and Environmental Control and Life Support System (ECLSS) thermal analyses is established. It is a composite catalog of Space Shuttle equipment, as defined in the Shuttle Operational Data Book. The major functions and expected usage of each component type are described. Functional descriptions are designed to provide a fundamental understanding of the Orbiter electrical equipment, to insure correlation of equipment usage within nominal analyses, and to aid analysts in the formulation of off-nominal, contingency analyses.

  13. Case report: Orbital epithelioid haemangioendothelioma.

    PubMed

    Zaragoza-Herrera, A; Morales-Baños, D R; Velasco-Ramos, P; Garrido-Sánchez, G A; López-Hernández, C M; Borbolla-Pertierra, A M

    2017-04-01

    A 13-year-old boy presented with right eye proptosis and lateral dystopia. A soft non-pulsatile mass was found in the superomedial orbital region. An excisional biopsy was performed, for which the histopathology reported an epithelioid haemangioendothelioma. Haemangioendothelioma is a borderline vascular lesion within the spectrum of clinically benign and malignant tumours. These can arise from soft tissue or bone. There are few reports of these tumours located in the orbit. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Spectroscopic Orbits of Three Binaries

    NASA Astrophysics Data System (ADS)

    Scarfe, C. D.

    2017-10-01

    This paper presents new spectroscopic orbits of three binaries with evolved primaries and periods of the order of a few years, two of them very eccentric. All the orbits were determined primarily from observations made with the DAO 1.2-m telescope and coudé spectrograph. Observations were obtained using the radial velocity spectrometer until it was decommissioned in 2004, and since then using a CCD detector, and cross-correlating the spectra with those of standard stars. It will be evident that the latter procedure leads to smaller observational scatter than the former did.

  15. Orbital Maneuvering Vehicle - New capability

    NASA Astrophysics Data System (ADS)

    Huber, William G.

    1987-10-01

    The Orbital Maneuvering Vehicle (OMV) program is reviewed with reference to the current status of the program, vehicle description, and mission capabilities. The OMV, which will be available in 1991, will be able to economically deliver and retreive spacecraft from orbits beyond the practical limits of the Shuttle. It will be capable of meeting the present needs of the Space Transportation System and its payloads and the future space activities associated with the Space Station. In addition to the inherent capability of the OMV, it can be enhanced by the addition of special purpose mission kits to meet special mission needs, such as servicing, refueling, and recovery of tumbling satellites.

  16. Orbital Maneuvering Vehicle - New capability

    NASA Technical Reports Server (NTRS)

    Huber, William G.

    1987-01-01

    The Orbital Maneuvering Vehicle (OMV) program is reviewed with reference to the current status of the program, vehicle description, and mission capabilities. The OMV, which will be available in 1991, will be able to economically deliver and retreive spacecraft from orbits beyond the practical limits of the Shuttle. It will be capable of meeting the present needs of the Space Transportation System and its payloads and the future space activities associated with the Space Station. In addition to the inherent capability of the OMV, it can be enhanced by the addition of special purpose mission kits to meet special mission needs, such as servicing, refueling, and recovery of tumbling satellites.

  17. Precise GPS orbits for geodesy

    NASA Technical Reports Server (NTRS)

    Colombo, Oscar L.

    1994-01-01

    The Global Positioning System (GPS) has become, in recent years, the main space-based system for surveying and navigation in many military, commercial, cadastral, mapping, and scientific applications. Better receivers, interferometric techniques (DGPS), and advances in post-processing methods have made possible to position fixed or moving receivers with sub-decimeter accuracies in a global reference frame. Improved methods for obtaining the orbits of the GPS satellites have played a major role in these achievements; this paper gives a personal view of the main developments in GPS orbit determination.

  18. Constraints on Triton's Orbital Evolution

    NASA Astrophysics Data System (ADS)

    Hamilton, D. P.; Zhang, K.; Agnor, C.

    2005-05-01

    Three models have been proposed for the capture origin of Triton: Collision with a preexisting satellite (Goldreich 1989), Gas drag (McKinnon 1990), and three-body exchange (Agnor and Hamilton 2004). All three scenarios put Triton onto a highly elongated orbit which is subsequently circularized by satellite tides. Our goal here is to use the current state of the Neptunian system to constrain these capture scenarios. Triton strongly affects inner satellites (or an inner disk) directly via close pericenter passages before its orbit circularizes. Since satellite tides nearly conserve angular momentum, a simple tidal model puts Triton's minimum pericenter distance at aT/2 ˜ 7RN, where aT is its current semimajor axis. Our initial simulations show that some satellites orbiting outside Proteus (the outermost of the inner satellites at a=4.67RN) can survive these Triton passages. So why are there no known moonlets beyond 4.67RN? Seeking answers, we have integrated Triton's orbit backwards in time with a more sophisticated model that includes J2, solar perturbations, and satellite tides. We find that Triton's pericenter smoothly descends toward 7RN, as in the simple tidal model, but with superimposed oscillations at i) 1/2 Neptune's orbital period and ii) the nodal and apsidal precession periods. At a ˜ 94RN Triton encounters a Kozai-like resonance between these precession periods which causes its pericenter to dip to ˜ 4.2RN - well within the current orbit of Proteus. If Triton's orbit were ever this large, then the early inner satellite system must have been much smaller than it is today. Additional apsidal and nodal resonances between an early Triton on a highly elliptical orbit and the small inner satellites (with resonant arguments like 2nT - 2Ω sat) are strong enough to drive moonlet inclinations up to several degrees. We are using the stengths and locations of these resonances to further limit possible capture and evolution scenarios and will report on the

  19. The Stability of Periodic Orbits.

    DTIC Science & Technology

    1981-01-21

    I AOB a7 PRIlNCETON UNIV NJ JOSEPH HENRY LABS OF PHYSICS FD 7/S THE STABILITY OF PERIODIC ORBITS. (U) JAN 81 L SNEDOOM N00014-77-C-0711 UNCLASSIFIE-D...NL I - The Stability of Periodic Orbits Leigh Sneddon* Joseph Henry Laboratories of Physics Princeton University Princeton, New Jersey 08544 ABSTRACT...eigenvalue of the Poincare map passes out through the unit circle at -1 : see Appendix 1) 9,10 are observed and are referred to as subharmonic or period

  20. Nodular Fasciitis of the Orbit.

    PubMed

    Compton, Christopher J; Clark, Jeremy D; Thompson, Matthew P; Lee, Hui Bae H; Nunery, William R

    A 13-month-old boy was presented with new onset proptosis of the right eye. CT scan and MRI showed an enhancing mass in the right superior orbit with local bone remodeling and erosion. A craniotomy was performed for biopsy and sub-total resection. Histopathology and immunohistochemistry confirmed the lesion to be nodular fasciitis. Nodular fasciitis lesions are classically found in the anterior ocular adnexa, especially in pediatric patients. This is the first reported case of nodular fasciitis arising in the posterior orbit of a child younger than 16.

  1. Current Issues in Orbital Debris

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas L.

    2011-01-01

    During the past two decades, great strides have been made in the international community regarding orbital debris mitigation. The majority of space-faring nations have reached a consensus on an initial set of orbital debris mitigation measures. Implementation of and compliance with the IADC and UN space debris mitigation guidelines should remain a high priority. Improvements of the IADC and UN space debris mitigation guidelines should continue as technical consensus permits. The remediation of the near-Earth space environment will require a significant and long-term undertaking.

  2. Bar shapes and orbital stochasticity

    SciTech Connect

    Athanassoula, E. )

    1990-06-01

    Several independent lines of evidence suggest that the isophotes or isodensities of bars in barred galaxies are not really elliptical in shape but more rectangular. The effect this might have on the orbits in two different types of bar potentials is studied, and it is found that in both cases the percentage of stochastic orbits is much larger when the shapes are more rectangularlike or, equivalently, when the m = 4 components are more important. This can be understood with the help of the Chirikov criterion, which can predict the limit for the onset of global stochasticity. 9 refs.

  3. Orbital resonances around black holes.

    PubMed

    Brink, Jeandrew; Geyer, Marisa; Hinderer, Tanja

    2015-02-27

    We compute the length and time scales associated with resonant orbits around Kerr black holes for all orbital and spin parameters. Resonance-induced effects are potentially observable when the Event Horizon Telescope resolves the inner structure of Sgr A*, when space-based gravitational wave detectors record phase shifts in the waveform during the resonant passage of a compact object spiraling into the black hole, or in the frequencies of quasiperiodic oscillations for accreting black holes. The onset of geodesic chaos for non-Kerr spacetimes should occur at the resonance locations quantified here.

  4. Orbital ATK CRS-7 Rollout

    NASA Image and Video Library

    2017-04-17

    A United Launch Alliance Atlas V rocket, with the Orbital ATK Cygnus pressurized cargo module, is transported along the road to the pad at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Orbital ATK's seventh commercial resupply services mission, CRS-7, is scheduled to launch to the International Space Station on April 18, 2017. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station. Liftoff is scheduled for 11:11 a.m. EDT.

  5. Orbital ATK CRS-7 Rollout

    NASA Image and Video Library

    2017-04-17

    A United Launch Alliance Atlas V rocket, with the Orbital ATK Cygnus pressurized cargo module, exits the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Orbital ATK's seventh commercial resupply services mission, CRS-7, is scheduled to launch to the International Space Station on April 18, 2017. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station. Liftoff is scheduled for 11:11 a.m. EDT.

  6. Orbital ATK CRS-7 Rollout

    NASA Image and Video Library

    2017-04-17

    The United Launch Alliance Atlas V rocket, with the Orbital ATK Cygnus pressurized cargo module, stands ready for launch on the pad at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Orbital ATK's seventh commercial resupply services mission, CRS-7, is scheduled to launch to the International Space Station on April 18, 2017. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station. Liftoff is scheduled for 11:11 a.m. EDT.

  7. Orbital ATK CRS-7 Rollout

    NASA Image and Video Library

    2017-04-17

    A United Launch Alliance Atlas V rocket, with the Orbital ATK Cygnus pressurized cargo module, has exited the Vertical Integration Facility for the trip to the pad at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Orbital ATK's seventh commercial resupply services mission, CRS-7, is scheduled to launch to the International Space Station on April 18, 2017. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station. Liftoff is scheduled for 11:11 a.m. EDT.

  8. Orbital ATK CRS-7 Rollout

    NASA Image and Video Library

    2017-04-17

    A United Launch Alliance Atlas V rocket, with the Orbital ATK Cygnus pressurized cargo module, begins to exit the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Orbital ATK's seventh commercial resupply services mission, CRS-7, is scheduled to launch to the International Space Station on April 18, 2017. Cygnus will deliver 7,600 pounds of supplies, equipment and scientific research materials to the space station. Liftoff is scheduled for 11:11 a.m. EDT.

  9. Odyssey Mars Orbiter - Thirteen Years of On-Orbit Navigation

    NASA Technical Reports Server (NTRS)

    Esposito, Pasquale; Jefferson, David C.; Lee, Julim

    2015-01-01

    The Odyssey spacecraft has been in Mars orbit since October 24, 2001 and has nearly completed 61,490 orbits. Navigation operational objectives include the following: Control the local mean solar time for science observations; for most of the mission, this varied from 3:45 pm to 5:20 pm. Currently, an orbit trim maneuver planned for November 10, 2015 will place Odyssey at 6:45 pm/6:45 am at equator crossings in order to observe early morning ground frost, fog and clouds. Initially, Odyssey was late by 42 minutes for an over-flight of the critical seven minutes of Phoenix's entry, descent and landing (EDL). Odyssey was successfully positioned for this over-flight using the Delta V from angular momentum desaturations (AMD). Similar results for the Mars Science Laboratory's EDL and Comet Siding Spring's minimum risk location will be presented. Odyssey has and continues to relay significant quantities of rover data. Navigation successfully models frequent AMD Delta Vs in order to generate accurate sixty-day trajectory predictions; a typical timing error is 25 seconds after 60 days. However, unexpected events, such as safe-mode entries with their larger and more frequent thrusting, severely impact that trajectory accuracy. Impacted trajectories can have timing errors ranging from a few minutes to ten-to-fifteen minutes after sixty-days. Other analyses (briefly stated) include: a) the offset of the orbital ground track pattern after an initial cycle of 30 days or 362 orbits and b) an operations environment of continuous thrusting if/when one of the three remaining reaction wheels fails.

  10. Orbital dynamics in galaxy mergers

    NASA Astrophysics Data System (ADS)

    Hoffman, Loren

    In the favored vacuum energy + cold dark matter (ACDM) cosmology, galaxies form through a hierarchical merging process. Mergers between comparable-mass sys tems are qualitatively different from the ongoing accretion of small objects by much larger ones, in that they can radically transform the nature of the merging objects, e.g. through violent relaxation of the stars and dark matter, triggered starbursts, and quasar activity. This thesis covers two phenomena unique to major galaxy mergers: the formation of supermassive black hole (SMBH) binary and triple systems, and the transformation of the stellar orbit structure through violent relaxation, triggered gas inflow, and star formation. In a major merger, the SMBHs can spiral in and form a bound binary in less than a Hubble time. If the binary lifetime exceeds the typical time between mergers, then triple black hole (BH) systems may form. We study the statistics of close triple-SMBH encounters in galactic nuclei by computing a series of three-body orbits with physically-motivated initial conditions appropriate for giant elliptical galaxies. Our simulations include a smooth background potential consisting of a stellar bulge plus a dark matter halo, drag forces due to gravitational radiation and dynamical friction on the stars and dark matter, and a simple model of the time evolution of the inner density profile under heating and mass ejection by the SMBHs. We find that the binary pair coalesces as a result of repeated close encounters in ~85% of our runs. In about 40% of the runs the lightest BH is left wandering through the galactic halo or escapes the galaxy altogether. The triple systems typically scour out cores with mass deficits ~1-2 times their total mass. The high coalescence rate and prevalence of very high-eccentricity orbits could provide interesting signals for the future Laser Interferometer Space Antenna (LISA). Our study of remnant orbit structure involved 42 disk-disk mergers at various gas fractions

  11. Precision Orbit Determination for the Lunar Reconnaissance Orbiter: orbit quality and gravity field estimation

    NASA Astrophysics Data System (ADS)

    Mazarico, E.; Rowlands, D. D.; Neumann, G. A.; Lemoine, F. G.; Torrence, M. H.; Smith, D. E.; Zuber, M. T.; Mao, D.

    2010-12-01

    We present results of the Precision Orbit Determination work undertaken by the Lunar Orbiter Laser Altimeter (LOLA) Science Team for the Lunar Reconnaissance Orbiter (LRO) mission, in order to meet the position knowledge accuracy requirements (50-m total position) and to precisely geolocate the LRO datasets. In addition to the radiometric tracking data, one-way laser ranges (LR) between Earth stations and the spacecraft are made possible by a small telescope mounted on the spacecraft high-gain antenna. The photons received from Earth are transmitted to one LOLA detector by a fiber optics bundle. The LOLA timing system enables 5-s LR normal points with precision better than 10cm. Other types of geodetic constraints are derived from the altimetric data itself. The orbit geometry can be constrained at the times of laser groundtrack intersections (crossovers). Due to the Moon's slow rotation, orbit solutions and normal equations including altimeter crossovers are processed and created in one month batches. Recent high-resolution topographic maps near the lunar poles are used to produce a new kind of geodetic constraints. Purely geometric, those do not necessitate actual groundtrack intersections. We assess the contributions of those data types, and the quality of our orbits. Solutions which use altimetric crossover meet the horizontal 50-m requirement, and perform usually better (10-20m). We also obtain gravity field solutions based on LRO and historical data. The various LRO data are accumulated into normal equations, separately for each one month batch and for each measurement type, which enables the final weights to be adjusted during the least-squares inversion step. Expansion coefficients to degree and order 150 are estimated, and a Kaula rule is still needed to stabilize the farside field. The gravity field solutions are compared to previous solutions (GLGM-3, LP150Q, SGM100h) and the geopotential predicted from the latest LOLA spherical harmonic expansion.

  12. Augmented orbiter heat rejection study

    NASA Technical Reports Server (NTRS)

    Hixon, C. W.

    1981-01-01

    Spacecraft radiator concepts are presented that relieve attitude restrictions required by the shuttle orbiter space radiator for baseline and extended capability STS missions. Cost effective heat rejection kits are considered which add additional capability in the form of attached spacelab radiators or a deployable radiator module.

  13. Energy and the Elliptical Orbit

    ERIC Educational Resources Information Center

    Nettles, Bill

    2009-01-01

    In the January 2007 issue of "The Physics Teacher," Prentis, Fulton, Hesse, and Mazzino describe a laboratory exercise in which students use a geometrical analysis inspired by Newton to show that an elliptical orbit and an inverse-square law force go hand in hand. The historical, geometrical, and teamwork aspects of the exercise are useful and…

  14. Viking orbiter stereo imaging catalog

    NASA Technical Reports Server (NTRS)

    Blasius, K. R.; Vertrone, A. V.; Lewis, B. H.; Martin, M. D.

    1982-01-01

    The extremely long mission of the two Viking Orbiter spacecraft produced a wealth of photos of surface features. Many of these photos can be used to form stereo images allowing the student of Mars to examine a subject in three dimensional. This catalog is a technical guide to the use of stereo coverage within the complex Viking imaging data set.

  15. THREE PLANETS ORBITING WOLF 1061

    SciTech Connect

    Wright, D. J.; Wittenmyer, R. A.; Tinney, C. G.; Bentley, J. S.; Zhao, Jinglin

    2016-02-01

    We use archival HARPS spectra to detect three planets orbiting the M3 dwarf Wolf 1061 (GJ 628). We detect a 1.36 M{sub ⊕} minimum-mass planet with an orbital period P = 4.888 days (Wolf 1061b), a 4.25 M{sub ⊕} minimum-mass planet with orbital period P = 17.867 days (Wolf 1061c), and a likely 5.21 M{sub ⊕} minimum-mass planet with orbital period P = 67.274 days (Wolf 1061d). All of the planets are of sufficiently low mass that they may be rocky in nature. The 17.867 day planet falls within the habitable zone for Wolf 1061 and the 67.274 day planet falls just outside the outer boundary of the habitable zone. There are no signs of activity observed in the bisector spans, cross-correlation FWHMs, calcium H and K indices, NaD indices, or Hα indices near the planetary periods. We use custom methods to generate a cross-correlation template tailored to the star. The resulting velocities do not suffer the strong annual variation observed in the HARPS DRS velocities. This differential technique should deliver better exploitation of the archival HARPS data for the detection of planets at extremely low amplitudes.

  16. Precision orbit computations for Starlette

    NASA Technical Reports Server (NTRS)

    Marsh, J. G.; Williamson, R. G.

    1976-01-01

    The Starlette satellite, launched in February 1975 by the French Centre National d'Etudes Spatiales, was designed to minimize the effects of nongravitational forces and to obtain the highest possible accuracy for laser range measurements. Analyses of the first four months of global laser tracking data confirmed the stability of the orbit and the precision to which the satellite's position is established.

  17. [Primary orbital tumors in children].

    PubMed

    Składzień, J; Olszewski, E; Reroń, E; Modrzejewski, M; Tomik, J; Paziewski, E

    1996-01-01

    We present the incidence, diagnosis and clinical picture of the primary orbital tumors in children. They were treated in ENT Clinic CM UJ in Kraków between 1981-1990 years. Discovered was preponderance of primary non malignant tumors. The most frequently encountered tumors were dermatomas, angiomas and among the malignant tumors-rhabdomyosarcoma.

  18. NASA Facts, Orbits and Revolutions.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This pamphlet is intended for senior high physics students. It contains information on the sidereal and synodic periods of revolution of an orbiting satellite, including their calculation. This pamphlet is one of the NASA Facts Science Series (each of which consists of four pages) and is designed to fit in the standard size three-ring notebook.…

  19. Launching Social Studies into Orbit.

    ERIC Educational Resources Information Center

    Stone, Kirk

    1986-01-01

    As a social studies educator, Christa McAuliffe was delighted that a "non-science teacher" was chosen to become the first teacher to orbit the earth. Her thoughts concerning the NASA space flight and its meaning for the social studies are discussed. (RM)

  20. Launching Social Studies into Orbit.

    ERIC Educational Resources Information Center

    Stone, Kirk

    1986-01-01

    As a social studies educator, Christa McAuliffe was delighted that a "non-science teacher" was chosen to become the first teacher to orbit the earth. Her thoughts concerning the NASA space flight and its meaning for the social studies are discussed. (RM)

  1. Three Planets Orbiting Wolf 1061

    NASA Astrophysics Data System (ADS)

    Wright, D. J.; Wittenmyer, R. A.; Tinney, C. G.; Bentley, J. S.; Zhao, Jinglin

    2016-02-01

    We use archival HARPS spectra to detect three planets orbiting the M3 dwarf Wolf 1061 (GJ 628). We detect a 1.36 M⊕ minimum-mass planet with an orbital period P = 4.888 days (Wolf 1061b), a 4.25 M⊕ minimum-mass planet with orbital period P = 17.867 days (Wolf 1061c), and a likely 5.21 M⊕ minimum-mass planet with orbital period P = 67.274 days (Wolf 1061d). All of the planets are of sufficiently low mass that they may be rocky in nature. The 17.867 day planet falls within the habitable zone for Wolf 1061 and the 67.274 day planet falls just outside the outer boundary of the habitable zone. There are no signs of activity observed in the bisector spans, cross-correlation FWHMs, calcium H & K indices, NaD indices, or Hα indices near the planetary periods. We use custom methods to generate a cross-correlation template tailored to the star. The resulting velocities do not suffer the strong annual variation observed in the HARPS DRS velocities. This differential technique should deliver better exploitation of the archival HARPS data for the detection of planets at extremely low amplitudes.

  2. Getting a Crew into Orbit

    ERIC Educational Resources Information Center

    Riddle, Bob

    2011-01-01

    Despite the temporary setback in our country's crewed space exploration program, there will continue to be missions requiring crews to orbit Earth and beyond. Under the NASA Authorization Act of 2010, NASA should have its own heavy launch rocket and crew vehicle developed by 2016. Private companies will continue to explore space, as well. At the…

  3. Myeloid Sarcoma in the Orbit.

    PubMed

    Qian, Xiaoxiao; Gigantelli, James W; Abromowitch, Minnie; Morgan, Linda A; Suh, Donny W

    2016-12-08

    The authors describe a case of myeloid sarcoma of the orbit in a pediatric patient. An 8-month-old male infant presented to the ophthalmology clinic with a left orbital mass, which had been increasing in size over the previous 2 months. The mass was initially diagnosed at another clinic as an infantile hemangioma, and had been treated with a topical formulation of timolol. In the ophthalmology clinic, orbital magnetic resonance imaging showed a solid enhancing mass. A biopsy was performed, and histopathology revealed myeloid sarcoma. The disease responded well to a standard chemotherapy regimen. Myeloid sarcoma is a rare, extra-medullary presentation that can occur as an isolated tumor, concurrently with or at relapse of acute myeloid leukemia. Because few cases of myeloid sarcoma in the orbit have been reported, this case report aids in the management of myeloid sarcoma in pediatric patients. The report describes an 8-month-old male infant, the youngest patient to develop myeloid sarcoma without preexisting acute myeloid leukemia. [J Pediatr Ophthalmol Strabismus. 2016;53:e64-e68.].

  4. Atypical presentations of orbital cysticercosis.

    PubMed

    Pushker, Neelam; Chaturvedi, Amrita; Balasubramanya, Ramamurthy; Bajaj, Mandeep S; Kumar, Neena; Sony, Parul

    2005-01-01

    We describe three patients with orbital cysticercosis who presented with atypical clinical or radiologic features previously unreported. All three patients had a cyst with a scolex on imaging studies. After 6 weeks of treatment, all three had almost complete resolution of their features.

  5. New instrument for orbital anthropometry.

    PubMed

    Kohout, M; Pai, L; Berenguer, B; Tayler, P; Pracharktam, N; Mulliken, J B

    1998-06-01

    A new instrument for orbital anthropometry is described. It consists of the base for a slit-lamp upon which the patient's head rests and rulers mounted on three independently movable axes. The z-axis probe is used to measure sagittal relationship between the corneal apices and points on the orbital perimeter. The instrument was tested against a sliding caliper and its accuracy was found to be within 0.2 mm or 2%. Intra- and inter-observer reliability were assessed by repeated measurements of two subjects by three observers. The intra-observer reliability was 0.99. Variations between observers was not significantly different for points orbitale inferius (oi), nasion (n), and orbitale superius (os), however, there was a statistically significant difference for measurement of orbitale laterale (ol). The correlation between anthropometric readings for lateral orbital wall to apex corneal (ol-ac) and CT scans for the same landmarks was assessed. Analysis of variance showed no difference between the measurement methods. This anthropometer is convenient and accurate for measurement of the sagittal orbital-globe relationships. A disadvantage is that it cannot be used intraoperatively.

  6. Energy and the Elliptical Orbit

    ERIC Educational Resources Information Center

    Nettles, Bill

    2009-01-01

    In the January 2007 issue of "The Physics Teacher," Prentis, Fulton, Hesse, and Mazzino describe a laboratory exercise in which students use a geometrical analysis inspired by Newton to show that an elliptical orbit and an inverse-square law force go hand in hand. The historical, geometrical, and teamwork aspects of the exercise are useful and…

  7. Lunar Reconnaissance Orbiter Artist Concept

    NASA Image and Video Library

    2008-07-24

    Artist rendering of the Lunar Reconnaissance Orbiter LRO, above the moon. LRO carries seven instruments that make comprehensive remote sensing observations of the moon and measurements of the lunar radiation environment. The LRO mission is managed by NASA Goddard for the Science Mission Directorate at NASA Headquarters in Washington. http://photojournal.jpl.nasa.gov/catalog/PIA18163

  8. Closed Orbits in Phase Space

    NASA Astrophysics Data System (ADS)

    Murphy, Andrew; Haestad, Jace; Morgan, Thomas

    2015-09-01

    We report characteristics of closed classical orbits in an electric field in phase space produced in photoabsorption. Rydberg states of atomic and molecular hydrogen and helium are considered. The core potential used for the hydrogen molecule is an effective one electron one center core potential evaluated at the internuclear equilibrium distance. Poincare surfaces of section in phase space are generated by integrating the equations of motion in semiparabolic coordinates u = (r + z) 1 / 2 and v = (r - z) 1 / 2, and plotting the location in phase space (pv versus v) whenever u = 0, with the electric field in the z direction. Combination orbits produced by Rydberg electron core scattering are studied and the evolution in phase space of these combination orbits due to scattering from one closed orbit into another is investigated. Connections are made to measured laser photoabsorption experiments that excite Rydberg states (20 < n < 30) and produce accompanying scaled energy recurrence spectra. The phase space structures responsible for the spectra are identified.

  9. Biomaterials for orbital fractures repair

    PubMed Central

    Totir, M; Ciuluvica, R; Dinu, I; Careba, I; Gradinaru, S

    2015-01-01

    The unique and complex anatomy of the orbit requires significant contouring of the implants to restore the proper anatomy. Fractures of the orbital region have an incidence of 10-25% from the total facial fractures and the most common age group was the third decade of life. The majority of cases required reconstruction of the orbital floor to support the globe position and restore the shape of the orbit. The reason for this was that the bony walls were comminuted and/ or bone fragments were missing. Therefore, the reconstruction of the missing bone was important rather than reducing the bone fragments. This could be accomplished by using various materials. There is hardly any anatomic region in the human body that is so controversial in terms of appropriate material used for fracture repair: non resorbable versus resorbable, autogenous/ allogeneic/ xenogenous versus alloplastic material, non-prebent versus preformed (anatomical) plates, standard versus custom-made plates, nonporous versus porous material, non-coated versus coated plates. Thus, the importance of the material used for reconstruction becomes more challenging for the ophthalmologist and the oral and maxillofacial surgeon. PMID:25914737

  10. Nuclear propulsion for orbital transfer

    SciTech Connect

    Beale, G.A.; Lawrence, T.J. )

    1989-06-01

    The state of the art in nuclear propulsion for orbital transfer is discussed. Cryogenic propulsion, electric propulsion, solar-thermal propulsion and direct nuclear propulsion are examined in this context. New technologies with exceptional promise are addressed, emphasizing the particle test bed nuclear engine.

  11. Getting a Crew into Orbit

    ERIC Educational Resources Information Center

    Riddle, Bob

    2011-01-01

    Despite the temporary setback in our country's crewed space exploration program, there will continue to be missions requiring crews to orbit Earth and beyond. Under the NASA Authorization Act of 2010, NASA should have its own heavy launch rocket and crew vehicle developed by 2016. Private companies will continue to explore space, as well. At the…

  12. The globe and orbit in Laron syndrome.

    PubMed

    Kornreich, L; Konen, O; Lilos, P; Laron, Z

    2011-09-01

    Patients with LS have an inborn growth hormone resistance, resulting in failure to generate IGF-1. The purpose of this study was to evaluate the size of the eye and orbit in LS. We retrospectively reviewed the MR imaging of the brain in 9 patients with LS for the following parameters: axial diameter of the globe, interzygomatic distance, perpendicular distance from the interzygomatic line to margins of the globe, medial-to-lateral diameter of the orbit at the anterior orbital rim, distance from the anterior orbital rim to the anterior globe, maximal distance between the medial walls of the orbits, lateral orbital wall angle, lateral orbital wall length, and mediolateral thickness of the intraorbital fat in the most cranial image of the orbit. All measurements were made bilaterally. Twenty patients referred for MR imaging for unrelated reasons served as control subjects. Compared with the control group, the patients with LS had a significantly smaller maximal globe diameter and shallower but wider orbits due to a shorter lateral wall, a smaller medial distance between the orbits, and a larger angle of the orbit. The ratio between the most anterior orbital diameter and the globe was greater than that in controls. The position of the globe was more anterior in relation to the interzygomatic line. Shallow and wide orbits and small globes relative to orbital size are seen in LS and may be secondary to IGF-1 deficiency.

  13. Orbital Debris Research at NASA

    NASA Technical Reports Server (NTRS)

    Stansbery, Eugene G.

    2009-01-01

    The United States has one of the most active programs of research of the orbital debris environment in the world. Much of the research is conducted by NASA s Orbital Debris Program Office at the Johnson Space Center. Past work by NASA has led to the development of national space policy which seeks to limit the growth of the debris population and limit the risk to spacecraft and humans in space and on the Earth from debris. NASA has also been instrumental in developing consistent international policies and standards. Much of NASA's efforts have been to measure and characterize the orbital debris population. The U.S. Department of Defense tracks and catalogs spacecraft and large debris with it's Space Surveillance Network while NASA concentrates on research on smaller debris. In low Earth orbit, NASA has utilized short wavelength radars such as Haystack, HAX, and Goldstone to statistically characterize the population in number, size, altitude, and inclination. For higher orbits, optical telescopes have been used. Much effort has gone into the understanding and removal of observational biases from both types of measurements. NASA is also striving to understand the material composition and shape characteristics of debris to assess these effects on the risk to operational spacecraft. All of these measurements along with data from ground tests provide the basis for near- and long-term modeling of the environment. NASA also develops tools used by spacecraft builders and operators to evaluate spacecraft and mission designs to assess compliance with debris standards and policies which limit the growth of the debris environment.

  14. Space Shuttle Orbiter-Illustration

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This illustration is an orbiter cutaway view with callouts. The orbiter is both the brains and heart of the Space Transportation System (STS). About the same size and weight as a DC-9 aircraft, the orbiter contains the pressurized crew compartment (which can normally carry up to seven crew members), the huge cargo bay, and the three main engines mounted on its aft end. There are three levels to the crew cabin. Uppermost is the flight deck where the commander and the pilot control the mission. The middeck is where the gallery, toilet, sleep stations, and storage and experiment lockers are found for the basic needs of weightless daily living. Also located in the middeck is the airlock hatch into the cargo bay and space beyond. It is through this hatch and airlock that astronauts go to don their spacesuits and marned maneuvering units in preparation for extravehicular activities, more popularly known as spacewalks. The Space Shuttle's cargo bay is adaptable to hundreds of tasks. Large enough to accommodate a tour bus (60 x 15 feet or 18.3 x 4.6 meters), the cargo bay carries satellites, spacecraft, and spacelab scientific laboratories to and from Earth orbit. It is also a work station for astronauts to repair satellites, a foundation from which to erect space structures, and a hold for retrieved satellites to be returned to Earth. Thermal tile insulation and blankets (also known as the thermal protection system or TPS) cover the underbelly, bottom of the wings, and other heat-bearing surfaces of the orbiter to protect it during its fiery reentry into the Earth's atmosphere. The Shuttle's 24,000 individual tiles are made primarily of pure-sand silicate fibers, mixed with a ceramic binder. The solid rocket boosters (SRB's) are designed as an in-house Marshall Space Flight Center project, with United Space Boosters as the assembly and refurbishment contractor. The solid rocket motor (SRM) is provided by the Morton Thiokol Corporation.

  15. [Orbital mycetoma: a case report].

    PubMed

    Gueye, N N; Seck, S M; Diop, Y; Ndiaye Sow, M N; Agboton, G; Diakhaté, M; Dieng, M; Dieng, M T

    2013-05-01

    Mycetomas are pathological processes through which exogenous fungal or actinomycotic etiological agents produce grains. These etiological agents live in the soil and plants of endemic areas. They are introduced traumatically, primarily into the foot. The orbital location is rare. We report the case of a 17-year-old student admitted for progressive left proptosis over 2 years, following penetrating trauma by a fork in a rural setting. Examination revealed a heterogenous orbital mass with multiple fistulae, producing pus and black grains, and suggested, due to the color of the grains, a diagnosis of fungal mycetoma. MRI revealed a destructive process at the level of the lamina papracea of the ethmoid and the orbital floor. Anatomopathological examination confirmed the fungal nature of the infection, while culture in Sabouraud's medium was inconclusive. The outcome was favorable after exenteration and debridementof the ipsilateral maxillary sinus and nasal cavities, along with 4 months of ketoconazole. No recurrence has been observed for 14 months after surgery. Mycetomas are endemic to northwest Africa. Most frequently located in the foot, they are seldom seen in the orbit. The color of the grains provides a clue as to the etiology. Black-grain mycetomas are always fungal and are treated surgically--essentially like cancer--as the persistence of a single grain will cause a recurrence. The orbital location of a mycetoma is rare. In the present case report, the concept of port of entry, the clinical appearance, and the color of the grains guided the diagnosis. The histological examination of the surgical specimen confirmed the diagnosis. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  16. SMC Orbital/Sub-Orbital Debris Mitigation User’s Handbook, Version 1.0

    DTIC Science & Technology

    2002-07-01

    SUBTITLE SMC Orbital/Sub- Orbital Debris Mitigation User’s Handbook Version 1.0 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6... Orbital Debris ..................................................................... A-6 4.1 Design Considerations...orbital (or space) debris and sub- orbital debris . Space debris is defined as any non-functioning man-made object orbiting the Earth. This definition

  17. Orbiter CIU/IUS communications hardware evaluation

    NASA Technical Reports Server (NTRS)

    Huth, G. K.

    1979-01-01

    The DOD and NASA inertial upper stage communication system design, hardware specifications and interfaces were analyzed to determine their compatibility with the Orbiter payload communications equipment (Payload Interrogator, Payload Signal Processors, Communications Interface Unit, and the Orbiter operational communications equipment (the S-Band and Ku-band systems). Topics covered include (1) IUS/shuttle Orbiter communications interface definition; (2) Orbiter avionics equipment serving the IUS; (3) IUS communication equipment; (4) IUS/shuttle Orbiter RF links; (5) STDN/TDRS S-band related activities; and (6) communication interface unit/Orbiter interface issues. A test requirement plan overview is included.

  18. 'Orbital volume restoration rate after orbital fracture'; a CT-based orbital volume measurement for evaluation of orbital wall reconstructive effect.

    PubMed

    Wi, J M; Sung, K H; Chi, M

    2017-01-13

    PurposeTo evaluate the effect of orbital reconstruction and factors related to the effect of orbital reconstruction by assessing of orbital volume using orbital computed tomography (CT) in cases of orbital wall fracture.MethodsIn this retrospective study, 68 patients with isolated blowout fractures were evaluated. The volumes of orbits and herniated orbital tissues were determined by CT scans using a three-dimensional reconstruction technique (the Eclipse Treatment Planning System). Orbital CT was performed preoperatively, immediately after surgery, and at final follow ups (minimum of 6 months). We evaluated the reconstructive effect of surgery making a new formula, 'orbital volume reconstruction rate' from orbital volume differences between fractured and contralateral orbits before surgery, immediately after surgery, and at final follow up.ResultsMean volume of fractured orbits before surgery was 23.01±2.60 cm(3) and that of contralateral orbits was 21.31±2.50 cm(3) (P=0.005). Mean volume of the fractured orbits immediately after surgery was 21.29±2.42 cm(3), and that of the contralateral orbits was 21.33±2.52 cm(3) (P=0.921). Mean volume of fractured orbits at final follow up was 21.50±2.44 cm(3), and that of contralateral orbits was 21.32±2.50 cm(3) (P=0.668). The mean orbital volume reconstruction rate was 100.47% immediately after surgery and 99.17% at final follow up. No significant difference in orbital volume reconstruction rate was observed with respect to fracture site or orbital implant type. Patients that underwent operation within 14 days of trauma had a better reconstruction rate at final follow up than patients who underwent operation over 14 days after trauma (P=0.039).ConclusionComputer-based measurements of orbital fracture volume can be used to evaluate the reconstructive effect of orbital implants and provide useful quantitative information. Significant reduction of orbital volume is observed immediately after orbital wall

  19. CT & CBCT imaging: assessment of the orbits.

    PubMed

    Hatcher, David C

    2012-11-01

    The orbits can be visualized easily on routine or customized protocols for computed tomography (CT) or cone beam CT (CBCT) scans. Detailed orbital investigations are best performed with 3-dimensional imaging methods. CT scans are preferred for visualizing the osseous orbital anatomy and fissures while magnetic resonance imaging is preferred for evaluating tumors and inflammation. CBCT provides high-resolution anatomic data of the sinonasal spaces, airway, soft tissue surfaces, and bones but does not provide much detail within the soft tissues. This article discusses CBCT imaging of the orbits, osseous anatomy of the orbits, and CBCT investigation of selected orbital pathosis.

  20. Orbital abscess from an odontogenic infection.

    PubMed

    Kim, Il-Kyu; Kim, Ju-Rok; Jang, Keum-Soo; Moon, Yeon-Sung; Park, Sun-Won

    2007-01-01

    An orbital abscess is a rare but serious complication of an odontogenic infection, which can lead to loss of vision or worse. This paper presents a case of orbital abscess secondary to an infection from the upper molar teeth, which extended to the retobulbar and posterosuperior region of the orbit, close to the superior orbital fissure. The infection spreaded to the pterygopalatine and infratemporal fossa and then to the orbit via the inferior orbital fissure. This paper reviews the clinical presentation, differential diagnosis, route of spread, value of serial CT scanning, treatment and possible complications.

  1. Conversion of Osculating Orbital Elements to Mean Orbital Elements

    NASA Technical Reports Server (NTRS)

    Der, Gim J.; Danchick, Roy

    1996-01-01

    Orbit determination and ephemeris generation or prediction over relatively long elapsed times can be accomplished with mean elements. The most simple and efficient method for orbit determination, which is also known as epoch point conversion, performs the conversion of osculating elements to mean elements by iterative procedures. Previous epoch point conversion methods are restricted to shorter elapsed times with linear convergence. The new method presented in this paper calculates an analytic initial guess of the unknown mean elements from a first order theory of secular perturbations and computes a transition matrix with accurate numerical partials. It thereby eliminates the problem of an inaccurate initial guess and an identity transition matrix employed by previous methods. With a good initial guess of the unknown mean elements and an accurate transition matrix, converging osculating elements to mean elements can be accomplished over long elapsed times with quadratic convergence.

  2. Binary Star Orbits. 4. Orbits of 18 Southern Interferometric Pairs

    DTIC Science & Technology

    2010-09-01

    Printed in the U.S.A. BINARY STAR ORBITS. IV. ORBITS OF 18 SOUTHERN INTERFEROMETRIC PAIRS Brian D. Mason1,3, William I. Hartkopf1,3, and Andrei...et al. (2006) 2.2 ( 3d ) HD 204236 ±4.9 ±0.018 ±3.9 ±12.0 ±2.6 ±0.25 ±14.0 4.1 21.0 22535−1137 MCA 73 18.71 0.0793 66.9 110.3 1991.52 0.061 277.0 2 4.7...They then described the detection by lunar occultation of three more components: E and F (both components of C) and G (a close component of B). While

  3. Frozen Orbits-Near Constant or Beneficially Varying Orbital Parameters.

    DTIC Science & Technology

    1986-05-15

    In this approach , the difference between the primary acceleration and all perturbing accelerations is integrated . A reference (or osculating) orbit is...PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT. TASK AREA & WORK UNIT NUMBERS .’ AFIT STUDENT AT: University of Colorado to II...I am thankful for the time and financial support making the degree possible. I thank Dr. Felix R. Hoots, Directorate of Astrodynamics at NORAD, and

  4. Orbiter CIU/IUS communications hardware evaluation

    NASA Technical Reports Server (NTRS)

    Huth, G. K.

    1979-01-01

    Inertial Upper Stage (IUS) and DoD Communication Interface Unit (CIU) communication system design, hardware specifications, and interfaces were evaluated to determine their compatibility with the Orbiter payload communication and data handling equipment and the Orbiter network communication equipment.

  5. Two designs for an orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Davis, Richard; Duquette, Miles; Fredrick, Rebecca; Schumacher, Daniel; Somers, Schaeffer; Stafira, Stanley; Williams, James; Zelinka, Mark

    1988-01-01

    The Orbital Transfer Vehicle (OTV) and systems were researched in the following areas: avionics, crew systems, electrical power systems, environmental control/life support systems, navigation and orbital maneuvers, propulsion systems, reaction control systems (RCS), servicing systems, and structures.

  6. MOOSE: Manned On-Orbit Servicing Equipment

    NASA Technical Reports Server (NTRS)

    Budinoff, J. (Editor); Leontsinis, N. (Editor); Lane, J. (Editor); Singh, R. (Editor); Angelone, K.; Boswell, C.; Chamberlain, I.; Concha, M.; Corrodo, M.; Custodio, O.

    1993-01-01

    The ability to service satellites has thus far been limited to low earth orbit platforms within reach of the Space Shuttle. Other orbits, such as geosynchronous orbits containing high-value spacecraft have not been attainable by a servicing vehicle. The useful life of a satellite can be extended by replacing spent propellant and damaged orbital replacement units, forestalling the need for eventual replacement. This growing need for satellite on-orbits servicing can be met by the Manned On-Orbit Servicing Equipment (MOOSE). Missions requiring orbit transfer capability, precision manipulation and maneuvering, and man-in-the-loop control can be accomplished using MOOSE. MOOSE is a flexible, reusable, single operator, aerobraking spacecraft designed to refuel, repair, and service orbiting spacecraft. MOOSE will be deployed from Space Station Freedom, (SSF), where it will be stored, resupplied, and refurbished.

  7. Orbiter Kapton wire operational requirements and experience

    NASA Technical Reports Server (NTRS)

    Peterson, R. V.

    1994-01-01

    The agenda of this presentation includes the Orbiter wire selection requirements, the Orbiter wire usage, fabrication and test requirements, typical wiring installations, Kapton wire experience, NASA Kapton wire testing, summary, and backup data.

  8. NASA Now: Orbital Mechanics: Earth Observing Satellites

    NASA Image and Video Library

    This NASA Now program is all about satellites and their orbits. Dr. James Gleason, project scientist for NPP, explains what it takes for a satellite to stay in orbit, why there are different types ...

  9. #1 Stereo Orbit - Launch to Feb 2011

    NASA Image and Video Library

    The STEREO mission consists of two spacecraft orbiting the Sun, one moving a bit faster than Earth and the other a bit slower. In the time since the STEREO spacecraft entered these orbits near the ...

  10. Overview of the Mars Reconnaissance Orbiter mission

    NASA Technical Reports Server (NTRS)

    Mateer, B.; Graf, J.; Zurek, R.; Jones, R.; Eisen, H.; Johnston, M.; Jai, D. B.

    2002-01-01

    The Mars Reconnaissance Orbiter will deliver to Mars orbit a payload to conduct remote sensing science observations, characterize sites for future landers, and provide critical telecom/navigation relay capability for follow-on missions.

  11. Sino-orbital fistula: two case reports.

    PubMed

    McNab, A A

    2000-08-01

    A fistula between the paranasal sinuses and the orbit as a late complication of orbital fractures is rare and may present with intermittent symptoms due to air passing into the orbit. A case note review of two patients with sino-orbital fistula is presented. Two patients, 23- and 30-year-old males, presented with intermittent symptoms of globe displacement, diplopia or discomfort months after repair of an orbital floor fracture with a synthetic orbital floor implant. The symptoms occurred after nose blowing. They were both cured by removal of the implant and partial removal of the tissue surrounding the implant. A sino-orbital fistula may complicate the otherwise routine repair of an orbital floor fracture, but may be cured by removal of the implant and part of the surrounding pseudocapsule.

  12. Orbiter Kapton wire operational requirements and experience

    NASA Astrophysics Data System (ADS)

    Peterson, R. V.

    1994-09-01

    The agenda of this presentation includes the Orbiter wire selection requirements, the Orbiter wire usage, fabrication and test requirements, typical wiring installations, Kapton wire experience, NASA Kapton wire testing, summary, and backup data.

  13. Curiosity Spotted on Parachute by Orbiter

    NASA Image and Video Library

    2012-08-06

    NASA Curiosity rover and its parachute were spotted by NASA Mars Reconnaissance Orbiter as Curiosity descended to the surface. The HiRISE camera captured this image of Curiosity while the orbiter was listening to transmissions from the rover.

  14. Management of ocular, orbital, and adnexal trauma

    SciTech Connect

    Spoor, T.C.; Nesi, F.A.

    1988-01-01

    This book contains 20 chapters. Some of the chapter titles are: The Ruptured Globe: Primary Care; Corneal Trauma, Endophthalmitis; Antibiotic Usage; Radiology of Orbital Trauma; Maxillofacial Fractures; Orbital Infections; and Basic Management of Soft Tissue Injury.

  15. Robustness analysis method for orbit control

    NASA Astrophysics Data System (ADS)

    Zhang, Jingrui; Yang, Keying; Qi, Rui; Zhao, Shuge; Li, Yanyan

    2017-08-01

    Satellite orbits require periodical maintenance due to the presence of perturbations. However, random errors caused by inaccurate orbit determination and thrust implementation may lead to failure of the orbit control strategy. Therefore, it is necessary to analyze the robustness of the orbit control methods. Feasible strategies which are tolerant to errors of a certain magnitude can be developed to perform reliable orbit control for the satellite. In this paper, first, the orbital dynamic model is formulated by Gauss' form of the planetary equation using the mean orbit elements; the atmospheric drag and the Earth's non-spherical perturbations are taken into consideration in this model. Second, an impulsive control strategy employing the differential correction algorithm is developed to maintain the satellite trajectory parameters in given ranges. Finally, the robustness of the impulsive control method is analyzed through Monte Carlo simulations while taking orbit determination error and thrust error into account.

  16. Rational orbits around charged black holes

    SciTech Connect

    Misra, Vedant; Levin, Janna

    2010-10-15

    We show that all eccentric timelike orbits in Reissner-Nordstroem spacetime can be classified using a taxonomy that draws upon an isomorphism between periodic orbits and the set of rational numbers. By virtue of the fact that the rationals are dense, the taxonomy can be used to approximate aperiodic orbits with periodic orbits. This may help reduce computational overhead for calculations in gravitational wave astronomy. Our dynamical systems approach enables us to study orbits for both charged and uncharged particles in spite of the fact that charged particle orbits around a charged black hole do not admit a simple one-dimensional effective potential description. Finally, we show that comparing periodic orbits in the Reissner-Nordstroem and Schwarzschild geometries enables us to distinguish charged and uncharged spacetimes by looking only at the orbital dynamics.

  17. Environmental dynamics at orbital altitudes

    NASA Technical Reports Server (NTRS)

    Karr, G. R.

    1976-01-01

    The influence of real satellite aerodynamics on the determination of upper atmospheric density was investigated. A method of analysis of satellite drag data is presented which includes the effect of satellite lift and the variation in aerodynamic properties around the orbit. The studies indicate that satellite lift may be responsible for the observed orbit precession rather than a super rotation of the upper atmosphere. The influence of simplifying assumptions concerning the aerodynamics of objects in falling sphere analysis were evaluated and an improved method of analysis was developed. Wind tunnel data was used to develop more accurate drag coefficient relationships for studying altitudes between 80 and 120 Km. The improved drag coefficient relationships revealed a considerable error in previous falling sphere drag interpretation. These data were reanalyzed using the more accurate relationships. Theoretical investigations of the drag coefficient in the very low speed ratio region were also conducted.

  18. The Orbiting Primate Experiment (OPE)

    NASA Technical Reports Server (NTRS)

    Bourne, G. H.; Debourne, M. N. G.; Mcclure, H. M.

    1977-01-01

    Instrumentation and life support systems are described for an experiment to determine the physiological effects of long term space flight on unrestrained, minimally instrumented rhesus macaques flown in orbit for periods up to six months or one year. On return from orbit, vestibular, cardiovascular, and skeletal muscle function will be tested. Blood chemistry and hematological studies will be conducted as well as tests of the immunological competence of selected animals. Nasal, rectal, and throat swabs will be used for bacterial and viral studies, and histopathological and histochemical investigations will be be made of all organs using light and electron microscopy. The experiment is being considered as a payload for the biomedical experiment scientific satellite.

  19. Elliptical orbit performance computer program

    NASA Technical Reports Server (NTRS)

    Myler, T. R.

    1981-01-01

    A FORTRAN coded computer program which generates and plots elliptical orbit performance capability of space boosters for presentation purposes is described. Orbital performance capability of space boosters is typically presented as payload weight as a function of perigee and apogee altitudes. The parameters are derived from a parametric computer simulation of the booster flight which yields the payload weight as a function of velocity and altitude at insertion. The process of converting from velocity and altitude to apogee and perigee altitude and plotting the results as a function of payload weight is mechanized with the ELOPE program. The program theory, user instruction, input/output definitions, subroutine descriptions and detailed FORTRAN coding information are included.

  20. Lunar Orbiter: Moon and Earth

    NASA Technical Reports Server (NTRS)

    1966-01-01

    The worlds first view of the Earth taken by a spacecraft from the vicinity of the Moon. The photo was transmitted to Earth by the United States Lunar Orbiter I and recieved at the NASA tracking station at Robledo de Chavela near Madrid, Spain. This crescent of the Earth was photographed August 23 at 16:35 GMT when the spacecraft was on its 16th orbit and just about to pass behind the Moon. This is the view the astronauts will have when they come around the backside of the Moon and face the Earth. The Earth is shown on the left of the photo with the U.S. east coast in the upper left, southern Europe toward the dark or night side of the Earth, and Antartica at the bottom of the Earth crescent. The surface of the Moon is shown on the right side of the photograph.

  1. Low thrust orbit determination program

    NASA Technical Reports Server (NTRS)

    Hong, P. E.; Shults, G. L.; Huling, K. R.; Ratliff, C. W.

    1972-01-01

    Logical flow and guidelines are provided for the construction of a low thrust orbit determination computer program. The program, tentatively called FRACAS (filter response analysis for continuously accelerating spacecraft), is capable of generating a reference low thrust trajectory, performing a linear covariance analysis of guidance and navigation processes, and analyzing trajectory nonlinearities in Monte Carlo fashion. The choice of trajectory, guidance and navigation models has been made after extensive literature surveys and investigation of previous software. A key part of program design relied upon experience gained in developing and using Martin Marietta Aerospace programs: TOPSEP (Targeting/Optimization for Solar Electric Propulsion), GODSEP (Guidance and Orbit Determination for SEP) and SIMSEP (Simulation of SEP).

  2. Pursuit/evasion in orbit

    NASA Technical Reports Server (NTRS)

    Kelley, H. J.; Cliff, E. M.; Lutze, F. H.

    1981-01-01

    Maneuvers available to a spacecraft having sufficient propellant to escape an antisatellite satellite (ASAT) attack are examined. The ASAT and the evading spacecraft are regarded as being in circular orbits, and equations of motion are developed for the ASAT to commence a two-impulse maneuver sequence. The ASAT employs thrust impulses which yield a minimum-time-to-rendezvous, considering available fuel. Optimal evasion is shown to involve only in-plane maneuvers, and begins as soon as the ASAT launch information is gathered and thrust activation can be initiated. A closest approach, along with a maximum evasion by the target spacecraft, is calculated to be 14,400 ft. Further research to account for ASATs in parking orbit and for generalization of a continuous control-modeled differential game is indicated.

  3. Pursuit/evasion in orbit

    NASA Astrophysics Data System (ADS)

    Kelley, H. J.; Cliff, E. M.; Lutze, F. H.

    1981-09-01

    Maneuvers available to a spacecraft having sufficient propellant to escape an antisatellite satellite (ASAT) attack are examined. The ASAT and the evading spacecraft are regarded as being in circular orbits, and equations of motion are developed for the ASAT to commence a two-impulse maneuver sequence. The ASAT employs thrust impulses which yield a minimum-time-to-rendezvous, considering available fuel. Optimal evasion is shown to involve only in-plane maneuvers, and begins as soon as the ASAT launch information is gathered and thrust activation can be initiated. A closest approach, along with a maximum evasion by the target spacecraft, is calculated to be 14,400 ft. Further research to account for ASATs in parking orbit and for generalization of a continuous control-modeled differential game is indicated.

  4. Analytic theory of orbit contraction

    NASA Technical Reports Server (NTRS)

    Vinh, N. X.; Longuski, J. M.; Busemann, A.; Culp, R. D.

    1977-01-01

    The motion of a satellite in orbit, subject to atmospheric force and the motion of a reentry vehicle are governed by gravitational and aerodynamic forces. This suggests the derivation of a uniform set of equations applicable to both cases. For the case of satellite motion, by a proper transformation and by the method of averaging, a technique appropriate for long duration flight, the classical nonlinear differential equation describing the contraction of the major axis is derived. A rigorous analytic solution is used to integrate this equation with a high degree of accuracy, using Poincare's method of small parameters and Lagrange's expansion to explicitly express the major axis as a function of the eccentricity. The solution is uniformly valid for moderate and small eccentricities. For highly eccentric orbits, the asymptotic equation is derived directly from the general equation. Numerical solutions were generated to display the accuracy of the analytic theory.

  5. SILEX in-orbit performances

    NASA Astrophysics Data System (ADS)

    Planche, Gilles; Chorvalli, Vincent

    2004-06-01

    PASTEL embarked on-board SPOT4, French LEO earth observation satellite, and OPALE mounted on-board ARTEMIS, European GEO telecommunication satellite are the key components of SILEX (Semi-conductor Inter-satellite Link Experiment) system. Launched in March 1998, PASTEL terminal was first verified via star tracking. Then, first SILEX optical communication was successfully performed in December 2001 with ARTEMIS at 31000 km. Following 12 months ARTEMIS orbit rising, SILEX commissioning phase was successfully achieved in spring 2003. Today, more than hundred successful optical communications have been achieved. On 1st of October 2003, the SILEX optical link was declared fully operational by the European and French space agencies. After a recall of SILEX architecture, design and on-ground verification, this paper reports on in-orbit results.

  6. Orbital assembly and maintenance study

    NASA Technical Reports Server (NTRS)

    Gorman, D.; Grant, C.; Kyrias, G.; Lord, C.; Rombach, J.; Salis, M.; Skidmore, R.; Thomas, R.

    1975-01-01

    The requirements, conceptual design, tradeoffs, procedures, and techniques for orbital assembly of the support structure of the microwave power transmission system and the radio astronomy telescope are described. Thermal and stress analyses, packaging, alignment, and subsystems requirements are included along with manned vs. automated and transportation tradeoffs. Technical and operational concepts for the manned and automated maintenance of satellites were investigated and further developed results are presented.

  7. The Orbital Workshop Sleep Compartment

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This wide-angle view is of the Orbital Workshop (OWS) sleep compartment, located in the lower level of the OWS. Each crewman was assigned a small space for sleeping and zipped themselves into sleeping bags stretched against the wall. Because of the absence of gravity, sleeping comfort was achieved in any position relative to the spacecraft; body support was not necessary. Sleeping could be accommodated quite comfortably in a bag that held the body at a given place in Skylab.

  8. Assembling the Skylab Orbital Workshop

    NASA Technical Reports Server (NTRS)

    1970-01-01

    This photograph was taken during assembly of the bottom and upper floors of the Skylab Orbital Workshop (OWS). The OWS was divided into two major compartments. The lower level provided crew accommodations for sleeping, food preparation and consumption, hygiene, waste processing and disposal, and performance of certain experiments. The upper level consisted of a large work area and housed water storage tanks, a food freezer, storage vaults for film, scientific airlocks, mobility and stability experiment equipment, and other experimental equipment.

  9. Vigilance problems in orbiter processing

    NASA Technical Reports Server (NTRS)

    Swart, William W.; Safford, Robert R.; Kennedy, David B.; Yadi, Bert A.; Barth, Timothy S.

    1993-01-01

    A pilot experiment was done to determine what factors influence potential performance errors related to vigilance in Orbiter processing activities. The selected activities include post flight inspection for burned gap filler material and pre-rollout inspection for tile processing shim material. It was determined that the primary factors related to performance decrement were the color of the target and the difficulty of the target presentation.

  10. Commercializing the transfer orbit stage

    NASA Technical Reports Server (NTRS)

    Miller, M. W.

    1984-01-01

    Key milestones necessary to establish the transfer orbit stage are examined. The selection of the project concept and synthesis of the company are described followed by an analysis venture capability support and the selection of a major aerospace company as prime contractor. A landmark agreement with NASA sanctioned the commercial TOS concept and provided the critical support necessary to raise the next round of venture capital. Project management and customer commitments are also discussed.

  11. Comet Odyssey: Comet Nucleus Orbiter

    NASA Astrophysics Data System (ADS)

    Weissman, P. R.; Smythe, W. D.; Spitz, S. J.; Bernard, D. E.; Bailey, R. W.

    2004-11-01

    Comet Odyssey is a comet nucleus orbiter mission, proposed to NASA's Discovery program in 2004. The goal of the mission is to completely characterize a cometary nucleus, both physically and compositionally, as can only be done during an extended rendezvous and not with a fast flyby. Comet Odyssey will launch in October 2009 on a Delta II 7925 and use a solar-electric powered spacecraft to effect a rendezvous with periodic comet 46P/Wirtanen in October 2013. Arrival is 96 days after perihelion at a heliocentric distance of 1.61 AU. Comet Odyssey's science payload includes narrow- and wide-angle CCD cameras, an infrared thermal imager, a gas chromatograph/mass spectrometer, an XRD/XRF dust compositional analyzer, and a dust counter and accumulation sensors. The Comet Odyssey spacecraft implementation uses a high heritage approach of flight proven and redundant hardware. The 3-engine ion propulsion subsystem is derived from that on Dawn but includes the capability for multi-engine thrusting. Comet Odyssey will approach the Wirtanen nucleus and make repeated slow flybys through the active cometary coma for a period of three months. It will then be placed in a ˜100-km radius orbit around the nucleus, with a plan to eventually orbit at 40-km altitude or less. From that altitude the narrow-angle camera will map the entire nucleus surface at 1 meter/pixel and the thermal imager will map at 19 meter/pixel. The orbital portion of the nominal mission will last 4.5 months, following the comet outward from the Sun to 3.3 AU as the comet evolves from an active to a quiescent state. En route to P/Wirtanen, the Comet Odyssey spacecraft will perform a close flyby of the 200-km diameter, G-type, main belt asteroid 19 Fortuna in January 2012 and make appropriate remote sensing observations.

  12. Viking orbiter system primary mission

    NASA Technical Reports Server (NTRS)

    Goudy, J. R.

    1977-01-01

    An overview of Viking Orbiter (VO) system and subsystem performances during the primary mission (the time period from VO-1 launch on August 20, 1975, through November 15, 1976) is presented. Brief descriptions, key design requirements, pertinent historical information, unique applications or situations, and predicted versus actual performances are included for all VO-1 and VO-2 subsystems, both individually and as an integrated system.

  13. Exotic Orbital Modes in Nuclei

    NASA Astrophysics Data System (ADS)

    von Neumann-Cosel, P.

    2003-06-01

    Experimental evidence for two types of collective excitations in nuclei generated by orbital motion is discussed, viz. a magnetic quadrupole twist mode observed in 180° electron scattering experiments and a toroidal electric dipole mode. The latter may be a source of low-energy pygmy dipole resonances observed in many nuclei. This is discussed in detail for the example of 208Pb based on the recent finding of a resonance at particle threshold in a high-resolution (γ, γ') experiment.

  14. Moving the Mars Reconnaissance Orbiter

    NASA Technical Reports Server (NTRS)

    2005-01-01

    In late October 2004, NASA's Mars Reconnaissance Orbiter was moved from the High Bay 100,000-class clean room at Lockheed Martin Space Systems, Denver, to the facility's Reverberant Acoustic Lab, where system environmental testing will continue through March 2005. Shown here are technicians guiding the spacecraft as it is lowered onto its transporter interface ring prior to installation of the shipping-container lid.

  15. Mars Orbiting Plasma Surveyor (MOPS)

    NASA Astrophysics Data System (ADS)

    Barabash, S.; Andre, M.; Blomberg, L. G.; Lundin, R.; Marklund, G. T.; Rathsman, P.; von Scheele, F.; Wahlund, J.-E.

    Mars Orbiting Plasma Surveyor (MOPS) S. Barabash (1), M. André (2), L. G. Blomberg (3), R. Lundin (1),G. T. Marklund (3), P. Rathsman (4), F. von Schéele (4), J.-E. Wahlund (2) (1) Swedish Institute of Space Physics, Kiruna, Sweden (stas@irf.se) (2) Swedish Institute of Space Physics, Uppsala, Sweden (3) Royal Institute of Technology, Department of Space and Plasma Physics , Stockholm, Sweden (4) Swedish Space Corporation, Solna, Sweden Mars Orbiting Plasma Surveyor (MOPS) is a microsatellite mission focused on studies of the near - Mars environment and the planet - solar wind interaction. The recent findings by the ESA Mars Express mission further highlighted the complexity of the processes taking place at the planet resulting from the solar wind interaction that strongly affect the planet's atmosphere. However, despite many previous Martian missions carrying different types of space plasma experiments, a comprehensive investigation including simultaneous measurements of particles, fields, and waves has never been performed. We propose a spinning spacecraft of a mass of 50-80 kg with a 10 kg payload which can "hitchhike" on another platform until Mars orbit insertion and then be released into a suitable orbit. The spacecraft design is based on the experience gained in very successful Swedish space plasma missions, Viking, Freja, Astrid -1, and Astrid - 2. In the present mission design, the MOPS spacecraft is equipped with its own 1m high gain antenna for direct communication with the Earth. The payload includes a wave experiment with wire booms, magnetometer with a rigid boom, electron and ion energy spectrometers and an ion mass analyser. An energetic neutral atom imager and an UV photometer may complete the core payload.

  16. Bond orbital modelling of heterostructures

    SciTech Connect

    Ünlü, Hilmi

    2016-03-25

    We propose a non-orthogonal sp{sup 3} hybrid bond orbital model to determine the electronic properties of semiconductor heterostructures. The model considers the non-orthogonality of sp{sup 3} hybrid states of nearest neighboring adjacent atoms using the intra-atomic Coulomb interactions corrected Hartree-Fock atomic energies and metallic contribution to calculate the valence band width energies of group IV elemental and group III-V and II-VI compound semiconductors without any adjustable parameter.

  17. Moving the Mars Reconnaissance Orbiter

    NASA Technical Reports Server (NTRS)

    2005-01-01

    In late October 2004, NASA's Mars Reconnaissance Orbiter was moved from the High Bay 100,000-class clean room at Lockheed Martin Space Systems, Denver, to the facility's Reverberant Acoustic Lab, where system environmental testing will continue through March 2005. Shown here are technicians guiding the spacecraft as it is lowered onto its transporter interface ring prior to installation of the shipping-container lid.

  18. Comet Orbits: Prediction, Nongravitational Effects

    NASA Technical Reports Server (NTRS)

    Marsden, B. G.

    1972-01-01

    The problems of calculating cometary orbits are discussed, with particular attention to that of predicting the returns of periodic comets. It is shown that the only inherent difficulty arises from the action of nongravitational forces. Recent progress toward an understanding of these forces is described in detail, both from the point of view of fitting the observations and of interpreting the forces in terms of the Whipple icy-conglomerate model.

  19. Geological exploration from orbital altitudes

    USGS Publications Warehouse

    Badgley, Peter C.; Fischer, William A.; Lyon, Ronald J. P.

    1965-01-01

    The National Aeronautics & Space Administration is planning geologic exploration from orbiting spacecraft. For that purpose it is evaluating new and refined exploration tools, often called remote sensors, including devices that are sensitive to force fields, such as gravity gradient systems, and devices that record the reflection or emission of electromagnetic energy. Both passive electromagnetic sensors (those that rely on natural sources of illumination, such as the Sun) and active electromagnetic sensors (which use an artificial source of illumination) are being considered.

  20. Introduction to Orbital Sciences Corporation

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A general overview of the Orbital Sciences Corporation (OSC) is presented. The following topics are covered: (1) manpower, facilities, and financial growth; (2) organization and management team; (3) the Space Data Division organization; (4) the Chandler facility; (5) Space Data-Products and Services; (6) space transportation systems; (7) spacecraft and space support systems; (8) turn-key suborbital launch services and support systems; and (9) OSC suborbital booster performance.