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Sample records for meteor crater arizona

  1. Barringer Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Barringer Crater, also known as 'Meteor Crater,' is a 1,300-meter (0.8 mile) diameter, 174-meter (570-feet) deep hole in the flat-lying desert sandstones 30 kilometers (18.6 miles) west of Winslow, Arizona. Since the 1890s geologic studies here played a leading role in developing an understanding of impact processes on the Earth, the moon and elsewhere in the solar system.

    This view was acquired by the Landsat 4 satellite on December 14, 1982. It shows the crater much as a lunar crater might appear through a telescope. Morning sun illumination is from the southeast (lower right). The prominent gully meandering across the scene is known as Canyon Diablo. It drains northward toward the Little Colorado River and eventually to the Grand Canyon. The Interstate 40 highway crosses and nearly parallels the northern edge of the scene.

    The ejecta blanket around the crater appears somewhat lighter than the surrounding terrain, perhaps in part due to its altered mineralogic content. However, foot traffic at this interesting site may have scarred and lightened the terrain too. Also, the roughened surface here catches the sunlight on the southerly slopes and protects a highly reflective patchy snow cover in shaded northerly slopes, further lightening the terrain as viewed from space on this date.

  2. Erosion of ejecta at Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    Grant, John A.; Schultz, Peter H.

    1993-01-01

    New methods for estimating erosion at Meteor Crater, Arizona, indicate that continuous ejecta deposits beyond 1/4-1/2 crater radii from the rim have been lowered less than 1 m on the average. This conclusion is based on the results of two approaches: coarsening of unweathered ejecta into surface lag deposits and calculation of the sediment budget within a drainage basin on the ejecta. Preserved ejecta morphologies beneath thin alluvium revealed by ground-penetrating radar provide qualitative support for the derived estimates. Although slightly greater erosion of less resistant ejecta locally has occurred, such deposits were limited in extent, particularly beyond 0.25R-0.5R from the present rim. Subtle but preserved primary ejecta features further support our estimate of minimal erosion of ejecta since the crater formed about 50,000 years ago. Unconsolidated deposits formed during other sudden extreme events exhibit similarly low erosion over the same time frame; the common factor is the presence of large fragments or large fragments in a matrix of finer debris. At Meteor Crater, fluvial and eolian processes remove surrounding fines leaving behind a surface lag of coarse-grained ejecta fragments that armor surfaces and slow vertical lowering.

  3. Impact mechanics at Meteor Crater, Arizona

    USGS Publications Warehouse

    Shoemaker, Eugene Merle

    1959-01-01

    Meteor Crator is a bowl-shaped depression encompassed by a rim composed chiefly of debris stacked in layers of different composition. Original bedrock stratigraphy is preserved, inverted, in the debris. The debris rests on older disturbed strata, which are turned up at moderate to steep angles in the wall of the crater and are locally overturned near the contact with the debris. These features of Meteor Crater correspond closely to those of a crater produced by nuclear explosion where depth of burial of the device was about 1/5 the diameter of the resultant crater. Studies of craters formed by detonation of nuclear devices show that structures of the crater rims are sensitive to the depth of explosion scaled to the yield of the device. The structure of Meteor Crater is such as would be produced by a very strong shock originating about at the level of the present crater floor, 400 feet below the original surface. At supersonic to hypersonic velocity an impacting meteorite penetrates the ground by a complex mechanism that includes compression of the target rocks and the meteorite by shock as well as hydrodynamic flow of the compressed material under high pressure and temperature. The depth of penetration of the meteorite, before it loses its integrity as a single body, is a function primarily of the velocity and shape of the meteorite and the densities and equations of state of the meteorite and target. The intensely compressed material then becomes dispersed in a large volume of breccia formed in the expanding shock wave. An impact velocity of about 15 km/sec is consonant with the geology of Meteor Crater in light of the experimental equation of state of iron and inferred compressibility of the target rocks. The kinetic energy of the meteorite is estimated by scaling to have been from 1.4 to 1.7 megatons TNT equivalent.

  4. Meteor Crater (Barringer Meteorite Crater), Arizona: Summary of Impact Conditions

    NASA Astrophysics Data System (ADS)

    Roddy, D. J.; Shoemaker, E. M.

    1995-09-01

    Meteor Crater in northern Arizona represents the most abundant type of impact feature in our Solar System, i.e., the simple bowl-shaped crater. Excellent exposures and preservation of this large crater and its ejecta blanket have made it a critical data set in both terrestrial and planetary cratering research. Recognition of the value of the crater was initiated in the early 1900's by Daniel Moreau Barringer, whose 27 years of exploration championed its impact origin [1]. In 1960, Shoemaker presented information that conclusively demonstrated that Meteor Crater was formed by hypervelocity impact [2]. This led the U.S. Geological Survey to use the crater extensively in the 1960-70's as a prime training site for the Apollo astronauts. Today, Meteor Crater continues to serve as an important research site for the international science community, as well as an educational site for over 300,000 visitors per year. Since the late 1950's, studies of this crater have presented an increasingly clearer view of this impact and its effects and have provided an improved view of impact cratering in general. To expand on this data set, we are preparing an upgraded summary on the Meteor Crater event following the format in [3], including information and interpretations on: 1) Inferred origin and age of the impacting body, 2) Inferred ablation and deceleration history in Earth's atmosphere, 3) Estimated speed, trajectory, angle of impact, and bow shock conditions, 4) Estimated coherence, density, size, and mass of impacting body, 5) Composition of impacting body (Canyon Diablo meteorite), 6) Estimated kinetic energy coupled to target rocks and atmosphere, 7) Terrain conditions at time of impact and age of impact, 8) Estimated impact dynamics, such as pressures in air, meteorite, and rocks, 9) Inferred and estimated material partitioning into vapor, melt, and fragments, 10) Crater and near-field ejecta parameters, 11) Rock unit distributions in ejecta blanket, 12) Estimated far

  5. NMR spectroscopic examination of shocked sandstone from Meteor Crater, Arizona

    SciTech Connect

    Cygan, R.T.; Boslough, M.B.; Kirkpatrick, R.J.

    1993-08-01

    Solid state silicon-29 nuclear magnetic resonance (NMR) spectroscopy has been used to characterize the formation of high pressure silica polymorphs and amorphous material associated with the shocked Coconino Sandstone from Meteor Crater, Arizona. Five samples of the sandstone were obtained from several locations at the crater to represent a range of shock conditions associated with the hypervelocity impact of a 30 m-diameter meteorite. The NMR spectra for these powdered materials exhibit peaks assigned to quartz, coesite, stishovite, and glass. A new resonance in two of the moderately shocked samples is also observed. This resonance has been identified as a densified form of amorphous silica with silicon in tetrahedra with one hydroxyl group. Such a phase is evidence for a shock-induced reaction between quartz and steam under high pressure conditions.

  6. NMR spectroscopic examination of shocked sandstone from meteor crater, Arizona

    SciTech Connect

    Cygan, R.T.; Boslough, M.B. ); Kirkpatrick, R.J. )

    1994-07-10

    Solid state silicon-29 nuclear magnetic resonance (NMR) spectroscopy has been used to characterize the formation of high pressure silica polymorphs and amorphous material associated with the shocked Coconino Sandstone from Meteor Crater, Arizona. Five samples of the sandstone were obtained from several locations at the crater to represent a range of shock conditions associated with the hypervelocity impact of a 30 m-diameter meteorite. The NMR spectra for these powdered materials exhibit peaks assigned to quartz, coesite, stishovite, and glass. A new resonance in two of the moderately shocked samples is also observed. This resonance has been identified as a densified form of amorphous silica with silicon in tetrahedra with one hydroxyl group. Such a phase is evidence for a shock-induced reaction between quartz and steam under high pressure conditions. [copyright] 1994 American Institute of Physics

  7. In situ 10Be-26Al exposure ages at Meteor Crater, Arizona

    USGS Publications Warehouse

    Nishiizumi, K.; Kohl, C.P.; Shoemaker, E.M.; Arnold, J.R.; Klein, J.; Fink, D.; Middleton, R.

    1991-01-01

    A new method of dating the surface exposure of rocks from in situ production of 10Be and 26Al has been applied to determine the age of Meteor Crater, Arizona. A lower bound on the crater age of 49,200 ?? 1,700 years has been obtained by this method. ?? 1991.

  8. In situ Be-10-Al-26 exposure ages at Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Kohl, C. P.; Arnold, J. R.; Shoemaker, E. M.; Klein, J.; Fink, D.; Middleton, R.

    1991-01-01

    A new method of dating the surface exposure of rocks from in situ production of Be-10 and Al-26 has been applied to determine the age of Meteor Crater, Arizona. A lower bound on the crater age of 49,200 + or - 1,700 years has been obtained by this method.

  9. In situ Be-10-Al-26 exposure ages at Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Kohl, C. P.; Arnold, J. R.; Shoemaker, E. M.; Klein, J.; Fink, D.; Middleton, R.

    1991-01-01

    A new method of dating the surface exposure of rocks from in situ production of Be-10 and Al-26 has been applied to determine the age of Meteor Crater, Arizona. A lower bound on the crater age of 49,200 + or - 1,700 years has been obtained by this method.

  10. Martian Meteor Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    20 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a fairly young meteor impact crater on Mars that is about the same size ( 1 kilometer; 0.62 miles) as the famous Meteor Crater in northern Arizona, U.S.A. Like the Arizona crater, boulders of ejected bedrock can be seen on the crater's ejecta blanket and in the crater itself. This crater is located in the Aethiopis region of Mars near 4.7oN, 224.1oW. Sunlight illuminates the scene from the lower left.

  11. Martian Meteor Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    20 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a fairly young meteor impact crater on Mars that is about the same size ( 1 kilometer; 0.62 miles) as the famous Meteor Crater in northern Arizona, U.S.A. Like the Arizona crater, boulders of ejected bedrock can be seen on the crater's ejecta blanket and in the crater itself. This crater is located in the Aethiopis region of Mars near 4.7oN, 224.1oW. Sunlight illuminates the scene from the lower left.

  12. The subsurface character of Meteor Crater, Arizona, as determined by ground-probing radar

    NASA Technical Reports Server (NTRS)

    Pilon, J. A.; Grieve, R. A. F.; Sharpton, V. L.

    1991-01-01

    The first results are presented from a ground-probing-radar survey of the subsurface structure of the Meteor Crater (Arizona) and the surrounding ejecta blanket. Five ground-probing radar transects were conducted, including three complete north-south transects of the interior floor of the crater and a partial east-west transect, connecting the three north-south surveys; the fifth transect was exterior to the crater. A number of subsurface dielectric reflectors were identified in both the interior and exterior transects of the Meteor Crater. The depths of most of these reflectors in the interior transects corresponds to lithological boundaries known from previous data from drilling and shaft excavations. However, some of the reflectors, e.g., the horizontal reflectors within the allochthonous breccia lens, were not known from previous work.

  13. Computer code simulations of the formation of Meteor Crater, Arizona - Calculations MC-1 and MC-2

    NASA Technical Reports Server (NTRS)

    Roddy, D. J.; Schuster, S. H.; Kreyenhagen, K. N.; Orphal, D. L.

    1980-01-01

    It has been widely accepted that hypervelocity impact processes play a major role in the evolution of the terrestrial planets and satellites. In connection with the development of quantitative methods for the description of impact cratering, it was found that the results provided by two-dimensional finite difference, computer codes is greatly improved when initial impact conditions can be defined and when the numerical results can be tested against field and laboratory data. In order to address this problem, a numerical code study of the formation of Meteor (Barringer) Crater, Arizona, has been undertaken. A description is presented of the major results from the first two code calculations, MC-1 and MC-2, that have been completed for Meteor Crater. Both calculations used an iron meteorite with a kinetic energy of 3.8 Megatons. Calculation MC-1 had an impact velocity of 25 km/sec and MC-2 had an impact velocity of 15 km/sec.

  14. Airflow analyses using thermal imaging in Arizona's Meteor Crater as part of METCRAX II

    NASA Astrophysics Data System (ADS)

    Grudzielanek, A. Martina; Vogt, Roland; Cermak, Jan; Maric, Mateja; Feigenwinter, Iris; Whiteman, C. David; Lehner, Manuela; Hoch, Sebastian W.; Krauß, Matthias G.; Bernhofer, Christian; Pitacco, Andrea

    2016-04-01

    In October 2013 the second Meteor Crater Experiment (METCRAX II) took place at the Barringer Meteorite Crater (aka Meteor Crater) in north central Arizona, USA. Downslope-windstorm-type flows (DWF), the main research objective of METCRAX II, were measured by a comprehensive set of meteorological sensors deployed in and around the crater. During two weeks of METCRAX II five infrared (IR) time lapse cameras (VarioCAM® hr research & VarioCAM® High Definition, InfraTec) were installed at various locations on the crater rim to record high-resolution images of the surface temperatures within the crater from different viewpoints. Changes of surface temperature are indicative of air temperature changes induced by flow dynamics inside the crater, including the DWF. By correlating thermal IR surface temperature data with meteorological sensor data during intensive observational periods the applicability of the IR method of representing flow dynamics can be assessed. We present evaluation results and draw conclusions relative to the application of this method for observing air flow dynamics in the crater. In addition we show the potential of the IR method for METCRAX II in 1) visualizing airflow processes to improve understanding of these flows, and 2) analyzing cold-air flows and cold-air pooling.

  15. Major Element Analysis of the Target Rocks at Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    See, Thomas H.; Hoerz, Friedrich; Mittlefehldt, David W.; Varley, Laura; Mertzman, Stan; Roddy, David

    2002-01-01

    We collected approximately 400 rock chips in continuous vertical profile at Meteor Crater, Arizona, representing, from bottom to top, the Coconino, Toroweap, Kaibab, and Moenkopi Formations to support ongoing compositional analyses of the impact melts and their stratigraphic source depth(s) and other studies at Meteor Crater that depend on the composition of the target rocks. These rock chips were subsequently pooled into 23 samples for compositional analysis by XRF (x ray fluorescence) methods, each sample reflecting a specific stratigraphic "subsection" approximately 5-10 in thick. We determined the modal abundance of quartz, dolomite, and calcite for the entire Kaibab Formation at vertical resolutions of 1-2 meters. The Coconino Formation composes the lower half of the crater cavity. It is an exceptionally pure sandstone. The Toroweap is only two inches thick and compositionally similar to Coconino, therefore, it is not a good compositional marker horizon. The Kaibab Formation is approximately 80 in thick. XRD (x ray diffraction) studies show that the Kaibab Formation is dominated by dolomite and quartz, albeit in highly variable proportions; calcite is a minor phase at best. The Kaibab at Meteor Crater is therefore a sandy dolomite rather than a limestone, consistent with pronounced facies changes in the Permian of SE Arizona over short vertical and horizontal distances. The Moenkopi forms the 12 in thick cap rock and has the highest Al2O3 and FeO concentrations of all target rocks. With several examples, we illustrate how this systematic compositional and modal characterization of the target ideologies may contribute to an understanding of Meteor Crater, such as the depth of its melt zone, and to impact cratering in general, such as the liberation of CO2 from shocked carbonates.

  16. Styles of crater gradation in Southern Ismenius Lacus, Mars: Clues from Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    Grant, J. A.; Schultz, P. H.

    1992-01-01

    Impact craters on the Earth and Mars provide a unique opportunity to quantify the gradational evolution of instantaneously created landforms in a variety of geologic settings. Unlike most landforms, the initial morphology associated with impact craters on both planets is uncomplicated by competition between construction and degradation during formation. Furthermore, pristine morphologies are both well-constrained and similar to a first order. The present study compares styles of graduation at Meteor Crater with those around selected craters (greater than 1-2 km in diameter) in southern Ismenius Lacus. Emphasis is placed on features visible in images near LANDSAT TM resolution (30-50 m/pixel) which is available for both areas. In contrast to Mars, vegetation on the Earth can modify gradation, but appears to influence overall rates and styles by 2X-3X rather than orders of magnitude. Further studies of additional craters in differing settings will refine the effects of this and other factors (e.g., substrate). Finally, by analogy with results from other terrestrial gradational surfaces this study should help provide constraints on climate over crater histories.

  17. Stable Ni isotopes and Be-10 and Al-26 in metallic spheroids from Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    Xue, S.; Herzog, G. F.; Hall, G. S.; Klein, J.; Middleton, R.; Juenemann, D.

    1993-01-01

    The Canyon Diablo spheroids, which are found around Meteor Crater, Arizona, are nickel-enriched objects with diameters from less than 0.1 to several mm. Previous studies have suggested that the enrichment of nickel resulted either from shock-melting of S-rich areas followed by solidification of the liquids under strongly non-equilibrium conditions at rapid cooling rates during flight outward from the crater or from the selective oxidation of iron. Isotopic studies are an effective tool for constraining the degree of open-system evaporation experienced by a system. The purpose of this study was to see whether Ni isotopes had been fractionated by volatilization during spheroid formation. In addition, the cosmogenic nuclides Be-10 and Al-26 were measured to try to estimate the depths in the parent meteorite from which the spheroids came.

  18. Characteristics of ejecta and alluvial deposits at Meteor Crater, Arizona and Odessa Craters, Texas: Results from ground penetrating radar

    NASA Technical Reports Server (NTRS)

    Grant, J. A.; Schultz, P. H.

    1991-01-01

    Previous ground penetrating radar (GRP) studies around 50,000 year old Meteor Crater revealed the potential for rapid, inexpensive, and non-destructive sub-surface investigations for deep reflectors (generally greater than 10 m). New GRP results are summarized focusing the shallow sub-surfaces (1-2 m) around Meteor Crater and the main crater at Odessa. The following subject areas are covered: (1) the thickness, distribution, and nature of the contact between surrounding alluvial deposits and distal ejecta; and (2) stratigraphic relationships between both the ejecta and alluvium derived from both pre and post crater drainages. These results support previous conclusions indicating limited vertical lowering (less than 1 m) of the distal ejecta at Meteor Crater and allow initial assessment of the gradational state if the Odessa craters.

  19. Age and geomorphic history of Meteor Crater, Arizona, from cosmogenic 36Cl and 14C in rock varnish

    USGS Publications Warehouse

    Phillips, F.M.; Zreda, M.G.; Smith, S.S.; Elmore, D.; Kubik, P.W.; Dorn, R.I.; Roddy, D.J.

    1991-01-01

    Using cosmogenic 36Cl buildup and rock varnish radiocarbon, we have measured the exposure age of rock surfaces at Meteor Crater, Arizona. Our 36Cl measurements on four dolomite boulders ejected from the crater by the impact yield a mean age of 49.7 ?? 0.85 ka, which is in excellent agreement with an average age of 49 ?? 3 ka obtained from thermoluminescence studies on shock-metamorphosed dolomite and quartz. These ages are supported by undetectably low 14C in the oldest rock varnish sample. ?? 1991.

  20. Age and geomorphic history of Meteor Crater, Arizona, from cosmogenic Cl-36 and C-14 in rock varnish

    NASA Astrophysics Data System (ADS)

    Phillips, Fred M.; Zreda, Marek G.; Smith, Stewart S.; Elmore, David; Kubik, Peter W.; Dorn, Ronald I.; Roddy, David J.

    1991-09-01

    Using cosmogenic Cl-36 buildup and rock varnish radiocarbon, the exposure age of rock surfaces at Meteor Crater, Arizona was measured, Cl-36 measurements on four dolomite boulders ejected from the crater by the impact yield a mean age of 49.7 + or - 0.85 ka, which is in excellent agreement with an average age of 49 + or - 3 ka obtained from thermoluminescence studies on shock-metamorphosed dolomite and quartz. These ages are supported by undetectably low C-14 in the oldest rock varnish sample.

  1. A seismic refraction technique used for subsurface investigations at Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    Ackermann, H. D.; Godson, R. H.; Watkins, J. S.

    1975-01-01

    A seismic refraction technique for interpreting the subsurface shape and velocity distribution of an anomalous surface feature such as an impact crater is described. The method requires the existence of a relatively deep refracting horizon and combines data obtained from both standard shallow refraction spreads and distant offset shots by using the deep refractor as a source of initial arrivals. Results obtained from applying the technique to Meteor crater generally agree with the known structure of the crater deduced by other investigators and provide new data on an extensive fractured zone surrounding the crater. The breccia lens is computed to extend roughly 190 m below the crater floor, about 30 m less than the value deduced from early drilling data. Rocks around the crater are fractured as distant as 900 m from the rim crest and to a depth of at least 800 m beneath the crater floor.

  2. A seismic refraction technique used for subsurface investigations at Meteor Crater, Arizona

    NASA Technical Reports Server (NTRS)

    Ackermann, H. D.; Godson, R. H.; Watkins, J. S.

    1975-01-01

    A seismic refraction technique for interpreting the subsurface shape and velocity distribution of an anomalous surface feature such as an impact crater is described. The method requires the existence of a relatively deep refracting horizon and combines data obtained from both standard shallow refraction spreads and distant offset shots by using the deep refractor as a source of initial arrivals. Results obtained from applying the technique to Meteor crater generally agree with the known structure of the crater deduced by other investigators and provide new data on an extensive fractured zone surrounding the crater. The breccia lens is computed to extend roughly 190 m below the crater floor, about 30 m less than the value deduced from early drilling data. Rocks around the crater are fractured as distant as 900 m from the rim crest and to a depth of at least 800 m beneath the crater floor.

  3. Meteor Crater, AZ

    NASA Image and Video Library

    2002-03-12

    The Barringer Meteorite Crater (also known as "Meteor Crater") is a gigantic hole in the middle of the arid sandstone of the Arizona desert. A rim of smashed and jumbled boulders, some of them the size of small houses, rises 50 m above the level of the surrounding plain. The crater itself is nearly a 1500 m wide, and 180 m deep. When Europeans first discovered the crater, the plain around it was covered with chunks of meteoritic iron - over 30 tons of it, scattered over an area 12 to 15 km in diameter. Scientists now believe that the crater was created approximately 50,000 years ago. The meteorite which made it was composed almost entirely of nickel-iron, suggesting that it may have originated in the interior of a small planet. It was 50 m across, weighed roughly 300,000 tons, and was traveling at a speed of 65,000 km per hour. This ASTER 3-D perspective view was created by draping an ASTER bands 3-2-1image over a digital elevation model from the US Geological Survey National Elevation Dataset. This image was acquired on May 17, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet. http://photojournal.jpl.nasa.gov/catalog/PIA03490

  4. Si-29 NMR spectroscopy of naturally-shocked quartz from Meteor Crater, Arizona: Correlation to Kieffer's classification scheme

    NASA Technical Reports Server (NTRS)

    Boslough, M. B.; Cygan, R. T.; Kirkpatrick, R. J.

    1993-01-01

    We have applied solid state Si-29 nuclear magnetic resonance (NMR) spectroscopy to five naturally-shocked Coconino Sandstone samples from Meteor Crater, Arizona, with the goal of examining possible correlations between NMR spectral characteristics and shock level. This work follows our observation of a strong correlation between the width of a Si-29 resonance and peak shock pressure for experimentally shocked quartz powders. The peak width increase is due to the shock-induced formation of amorphous silica, which increases as a function of shock pressure over the range that we studied (7.5 to 22 GPa). The Coconino Sandstone spectra are in excellent agreement with the classification scheme of Kieffer in terms of presence and approximate abundances of quartz, coesite, stishovite, and glass. We also observe a new resonance in two moderately shocked samples that we have tentatively identified with silicon in tetrahedra with one hydroxyl group in a densified form of amorphous silica.

  5. Si-29 NMR spectroscopy of naturally-shocked quartz from Meteor Crater, Arizona: Correlation to Kieffer's classification scheme

    NASA Technical Reports Server (NTRS)

    Boslough, M. B.; Cygan, R. T.; Kirkpatrick, R. J.

    1993-01-01

    We have applied solid state Si-29 nuclear magnetic resonance (NMR) spectroscopy to five naturally-shocked Coconino Sandstone samples from Meteor Crater, Arizona, with the goal of examining possible correlations between NMR spectral characteristics and shock level. This work follows our observation of a strong correlation between the width of a Si-29 resonance and peak shock pressure for experimentally shocked quartz powders. The peak width increase is due to the shock-induced formation of amorphous silica, which increases as a function of shock pressure over the range that we studied (7.5 to 22 GPa). The Coconino Sandstone spectra are in excellent agreement with the classification scheme of Kieffer in terms of presence and approximate abundances of quartz, coesite, stishovite, and glass. We also observe a new resonance in two moderately shocked samples that we have tentatively identified with silicon in tetrahedra with one hydroxyl group in a densified form of amorphous silica.

  6. Zhamanshin meteor crater

    NASA Technical Reports Server (NTRS)

    Florenskiy, P. V.; Dabizha, A. I.

    1987-01-01

    A historical survey and geographic, geologic and geophysical characteristics, the results of many years of study of the Zhamanshin meteor crater in the Northern Aral region, are reported. From this data the likely initial configuration and cause of formation of the crater are reconstructed. Petrographic and mineralogical analyses are given of the brecciated and remelted rocks, of the zhamanshinites and irgizite tektites in particular. The impact melting, dispersion and quenching processes resulting in tektite formation are discussed.

  7. Transformations to granular zircon revealed: Twinning, reidite, and ZrO2 in shocked zircon from Meteor Crater (Arizona, USA)

    USGS Publications Warehouse

    Cavosie, Aaron; Timms, Nicholas E.; Erickson, Timmons M.; Hagerty, Justin J.; Hörz, Friedrich

    2016-01-01

    Granular zircon in impact environments has long been recognized but remains poorly understood due to lack of experimental data to identify mechanisms involved in its genesis. Meteor Crater in Arizona (United States) contains abundant evidence of shock metamorphism, including shocked quartz, the high pressure polymorphs coesite and stishovite, diaplectic SiO2 glass, and lechatelierite (fused SiO2). Here we report the presence of granular zircon, a new shocked mineral discovery at Meteor Crater, that preserve critical orientation evidence of specific transformations that occurred during its formation at extreme impact conditions. The zircon grains occur as aggregates of sub-µm neoblasts in highly shocked Coconino Formation Sandstone (CFS) comprised of lechatelierite. Electron backscatter diffraction shows that each grain consists of multiple domains, some with boundaries disoriented by 65°, a known {112} shock-twin orientation. Other domains have crystallographic c-axes in alignment with {110} of neighboring domains, consistent with the former presence of the high pressure ZrSiO4 polymorph reidite. Additionally, nearly all zircon preserve ZrO2 + SiO2, providing evidence of partial dissociation. The genesis of CFS granular zircon started with detrital zircon that experienced shock-twinning and reidite formation from 20 to 30 GPa, ultimately yielding a phase that retained crystallographic memory; this phase subsequently recrystallized to systematically oriented zircon neoblasts, and in some areas partially dissociated to ZrO2. The lechatelierite matrix, experimentally constrained to form at >2000 °C, provided an ultra high-temperature environment for zircon dissociation (~1670 °C) and neoblast formation. The capacity of granular zircon to preserve a cumulative P-T record has not been recognized previously, and provides a new method for retrieving histories of impact-related mineral transformations in the crust at conditions far beyond which most rocks melt.

  8. Meteor Crater, AZ

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Barringer Meteorite Crater (also known as 'Meteor Crater') is a gigantic hole in the middle of the arid sandstone of the Arizona desert. A rim of smashed and jumbled boulders, some of them the size of small houses, rises 50 m above the level of the surrounding plain. The crater itself is nearly a 1500 m wide, and 180 m deep. When Europeans first discovered the crater, the plain around it was covered with chunks of meteoritic iron - over 30 tons of it, scattered over an area 12 to 15 km in diameter. Scientists now believe that the crater was created approximately 50,000 years ago. The meteorite which made it was composed almost entirely of nickel-iron, suggesting that it may have originated in the interior of a small planet. It was 50 m across, weighed roughly 300,000 tons, and was traveling at a speed of 65,000 km per hour. This ASTER 3-D perspective view was created by draping an ASTER bands 3-2-1image over a digital elevation model from the US Geological Survey National Elevation Dataset.

    This image was acquired on May 17, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18,1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The Terra mission is part of NASA's Earth Science Enterprise, along

  9. Ground Penetrating Radar Field Studies of Lunar-Analog Geologic Settings and Processes: Barringer Meteor Crater and Northern Arizona Volcanics

    NASA Astrophysics Data System (ADS)

    Russell, P. S.; Grant, J. A.; Williams, K. K.; Bussey, B.

    2010-12-01

    Ground-Penetrating Radar (GPR) data from terrestrial analog environments can help constrain models for evolution of the lunar surface, aid in interpretation of orbital SAR data, and help predict what might be encountered in the subsurface during future, landed, scientific or engineering operations on the Moon. GPR can yield insight into the physical properties, clast-size distribution, and layering of the subsurface, granting a unique view of the processes affecting an area over geologic time. The purpose of our work is to demonstrate these capabilities at sites at which geologic processes, settings, and/or materials are similar to those that may be encountered on the moon, especially lava flows, impact-crater ejecta, and layered materials with varying properties. We present results from transects obtained at Barringer Meteor Crater, SP Volcano cinder cone, and Sunset Crater Volcano National Monument, all in northern Arizona. Transects were taken at several sites on the ejecta of Meteor Crater, all within a crater radius (~400 m) of the crater rim. Those taken across ejecta lobes or mounds reveal the subsurface contact of the ejecta upper surface and overlying, embaying sediments deposited by later alluvial, colluvial, and/or aeolian processes. Existing mine shafts and pits on the south side of the crater provide cross sections of the subsurface against which we compare adjacent GPR transects. The ‘actual’ number, size, and depth of clasts in the top 1-2 m of the subsurface are estimated from photos of the exposed cross sections. In GPR radargrams, reflections attributed to blocks in the top 2-5 m of the subsurface are counted, and their depth distribution noted. Taking GPR measurements along a transect at two frequencies (200 and 400 MHz) and to various depths, we obtain the ratio of the actual number of blocks in the subsurface to the number detectable with GPR, as well as an assessment of how GPR detections in ejecta decline with depth and depend on antenna

  10. Ejecta patterns of Meteor Crater, Arizona derived from the linear un-mixing of TIMS data and laboratory thermal emission spectra

    NASA Technical Reports Server (NTRS)

    Ramsey, Michael S.; Christensen, Philip R.

    1992-01-01

    Accurate interpretation of thermal infrared data depends upon the understanding and removal of complicating effects. These effects may include physical mixing of various mineralogies and particle sizes, atmospheric absorption and emission, surficial coatings, geometry effects, and differential surface temperatures. The focus is the examination of the linear spectral mixing of individual mineral or endmember spectra. Linear addition of spectra, for particles larger than the wavelength, allows for a straight-forward method of deconvolving the observed spectra, predicting a volume percent of each endmember. The 'forward analysis' of linear mixing (comparing the spectra of physical mixtures to numerical mixtures) has received much attention. The reverse approach of un-mixing thermal emission spectra was examined with remotely sensed data, but no laboratory verification exists. Understanding of the effects of spectral mixing on high resolution laboratory spectra allows for the extrapolation to lower resolution, and often more complicated, remotely gathered data. Thermal Infrared Multispectral Scanner (TIMS) data for Meteor Crater, Arizona were acquired in Sep. 1987. The spectral un-mixing of these data gives a unique test of the laboratory results. Meteor Crater (1.2 km in diameter and 180 m deep) is located in north-central Arizona, west of Canyon Diablo. The arid environment, paucity of vegetation, and low relief make the region ideal for remote data acquisition. Within the horizontal sedimentary sequence that forms the upper Colorado Plateau, the oldest unit sampled by the impact crater was the Permian Coconino Sandstone. A thin bed of the Toroweap Formation, also of Permian age, conformably overlays the Coconino. Above the Toroweap lies the Permian Kiabab Limestone which, in turn, is covered by a thin veneer of the Moenkopi Formation. The Moenkopi is Triassic in age and has two distinct sub-units in the vicinity of the crater. The lower Wupatki member is a fine

  11. Planetary science: Meteor Crater formed by low-velocity impact.

    PubMed

    Melosh, H J; Collins, G S

    2005-03-10

    Meteor Crater in Arizona was the first terrestrial structure to be widely recognized as a meteorite impact scar and has probably been more intensively studied than any other impact crater on Earth. We have discovered something surprising about its mode of formation--namely that the surface-impact velocity of the iron meteorite that created Meteor Crater was only about 12 km s(-1). This is close to the 9.4 km s(-1) minimum originally proposed but far short of the 15-20 km s(-1) that has been widely assumed--a realization that clears up a long-standing puzzle about why the crater does not contain large volumes of rock melted by the impact.

  12. Planetary science: Meteor Crater formed by low-velocity impact

    NASA Astrophysics Data System (ADS)

    Melosh, H. J.; Collins, G. S.

    2005-03-01

    Meteor Crater in Arizona was the first terrestrial structure to be widely recognized as a meteorite impact scar and has probably been more intensively studied than any other impact crater on Earth. We have discovered something surprising about its mode of formation - namely that the surface-impact velocity of the iron meteorite that created Meteor Crater was only about 12 km s-1. This is close to the 9.4 km s-1 minimum originally proposed but far short of the 15-20 km s-1 that has been widely assumed - a realization that clears up a long-standing puzzle about why the crater does not contain large volumes of rock melted by the impact.

  13. Strawberry Crater Roadless Areas, Arizona

    SciTech Connect

    Wolfe, E.W.; Light, T.D.

    1984-01-01

    The results of a mineral survey conducted in 1980 in the Strawberry Crater Roadless Areas, Arizona, indicate little promise for the occurrence of metallic mineral or fossil fuel resources in the area. The area contains deposits of cinder, useful for the production of aggregate block, and for deposits of decorative stone; however, similar deposits occur in great abundance throughout the San Francisco volcanic field outside the roadless areas. There is a possibility that the Strawberry Crater Roadless Areas may overlie part of a crustal magma chamber or still warm pluton related to the San Francisco Mountain stratovolcano or to basaltic vents of late Pleistocene or Holocene age. Such a magma chamber or pluton beneath the Strawberry Crater Roadless Areas might be an energy source from which a hot-, dry-rock geothermal energy system could be developed, and a probable geothermal resource potential is therefore assigned to these areas.

  14. STRAWBERRY CRATER ROADLESS AREAS, ARIZONA.

    USGS Publications Warehouse

    Wolfe, Edward W.; Light, Thomas D.

    1984-01-01

    The results of a mineral survey conducted in the Strawberry Crater Roadless Areas, Arizona, indicate little promise for the occurrence of metallic mineral or fossil fuel resources in the area. The area contains deposits of cinder, useful for the production of aggregate block, and for deposits of decorative stone; however, similar deposits occur in great abundance throughout the San Francisco volcanic field outside the roadless areas. There is a possibility that the Strawberry Crater Roadless Areas may overlie part of a crustal magma chamber or still warm pluton related to the San Francisco Mountain stratovolcano or to basaltic vents of late Pleistocene or Holocene age. Such a magma chamber or pluton beneath the Strawberry Crater Roadless Areas might be an energy source from which a hot-, dry-rock geothermal energy system could be developed, and a probable geothermal resource potential is therefore assigned to these areas. 9 refs.

  15. Harvey Nininger's 1948 attempt to nationalize Meteor Crater.

    NASA Astrophysics Data System (ADS)

    Plotkin, H.; Clarke, R. S., Jr.

    2008-10-01

    Harvey Nininger successfully petitioned the American Astronomical Society to pass a motion in support of nationalizing Meteor Crater, Arizona, at its June 1948 meeting. He alleged that the Barringer family, who held title to the crater, was depriving American citizens of its scenic beauty and scientific value. He then reportedly went on to make the unauthorized—and false—claim that the family would be receptive to a fair purchase offer for the crater. The Barringers, who had not been given advance warning of the petition and were not present at the meeting, felt ambushed. They quickly and forcefully rebutted Nininger’s allegations, made it clear they had no intention of relinquishing their title to the crater, and terminated his exploration rights. What led Nininger to such a curious and self-defeating act? Based on our reading of his voluminous personal correspondence, we conclude that it was rooted primarily in his complex relationship with Frederick Leonard and Lincoln LaPaz, and his desire to establish a national institute for meteoritical research—with them, originally, but after a serious falling out, on his own. Prevented from moving his American Meteorite Museum to the crater rim, Nininger wondered what would happen if the crater was nationalized and made into a public park, with an accompanying tourist center and museum. With characteristic élan, he could picture himself at its head, with a secure salary and adequate space to exhibit his meteorite collection.

  16. Coon Mountain controversies - Meteor Crater and the development of impact theory

    NASA Astrophysics Data System (ADS)

    Hoyt, William Graves

    The dispute over the meteoritic or volcanic origin of Meteor Crater in Arizona is reviewed. The role of Daniel Moreau Barringer in demonstrating the truth of the meteorite hypothesis is shown. The significance of the methods used to resolve the controversy to the study of the origin of the solar system is addressed.

  17. Siderophile element fractionation in meteor crater impact glasses and metallic spherules

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; See, T. H.; Scott, E. R. D.

    1993-01-01

    Meteor Crater, Arizona provides an opportunity to study, in detail, elemental fractionation processes occurring during impacts through the study of target rocks, meteorite projectile and several types of impact products. We have performed EMPA and INAA on target rocks, two types of impact glass and metallic spherules from Meteor Crater. Using literature data for the well studied Canyon Diablo iron we can show that different siderophite element fractionations affected the impact glasses than affected the metallic spherules. The impact glasses primarily lost Au, while the metallic spherules lost Fe relative to other siderophile elements.

  18. NASA Meteor Cam Video of June 2, 2016 Arizona Fireball

    NASA Image and Video Library

    Video obtained from the NASA meteor camera situated at the MMT Observatory on the site of the Fred Lawrence Whipple Observatory, located on Mount Hopkins, Arizona, in the Santa Rita Mountains. Cred...

  19. Radar scattering mechanisms within the meteor crater ejecta blanket: Geologic implications and relevance to Venus

    NASA Technical Reports Server (NTRS)

    Garvin, J. B.; Campbell, B. A.; Zisk, S. H.; Schaber, Gerald G.; Evans, C.

    1989-01-01

    Simple impact craters are known to occur on all of the terrestrial planets and the morphologic expression of their ejecta blankets is a reliable indicator of their relative ages on the Moon, Mars, Mercury, and most recently for Venus. It will be crucial for the interpretation of the geology of Venus to develop a reliable means of distinguishing smaller impact landforms from volcanic collapse and explosion craters, and further to use the observed SAR characteristics of crater ejecta blankets (CEB) as a means of relative age estimation. With these concepts in mind, a study was initiated of the quantitative SAR textural characteristics of the ejecta blanket preserved at Meteor Crater, Arizona, the well studied 1.2 km diameter simple crater that formed approx. 49,000 years ago from the impact of an octahedrite bolide. While Meteor Crater was formed as the result of an impact into wind and water lain sediments and has undergone recognizable water and wind related erosion, it nonetheless represents the only well studied simple impact crater on Earth with a reasonably preserved CEB. Whether the scattering behavior of the CEB can provide an independent perspective on its preservation state and style of erosion is explored. Finally, airborne laser altimeter profiles of the microtopography of the Meteor Crater CEB were used to further quantify the subradar pizel scale topographic slopes and RMS height variations for comparisons with the scattering mechanisms computed from SAR polarimetry. A preliminary assessment was summarized of the L-band radar scattering mechanisms within the Meteor Crater CEB as derived from a NASA/JPL DC-8 SAR Polarimetry dataset acquired in 1988, and the dominant scattering behavior was compared with microtopographic data (laser altimeter profiles and 1:10,000 scale topographic maps).

  20. Devolatilization or melting of carbonates at Meteor Crater, AZ?

    NASA Astrophysics Data System (ADS)

    Hörz, F.; Archer, P. D.; Niles, P. B.; Zolensky, M. E.; Evans, M.

    2015-06-01

    We have investigated the carbonates in the impact melts and in a monolithic clast of highly shocked Coconino sandstone of Meteor Crater, AZ to evaluate whether melting or devolatilization is the dominant response of carbonates during high-speed meteorite impact. Both melt- and clast-carbonates are calcites that have identical crystal habits and that contain anomalously high SiO2 and Al2O3. Also, both calcite occurrences lack any meteoritic contamination, such as Fe or Ni, which is otherwise abundantly observed in all other impact melts and their crystallization products at Meteor Crater. The carbon and oxygen isotope systematics for both calcite deposits suggest a low temperature environment (<100 °C) for their precipitation from an aqueous solution, consistent with caliche. We furthermore subjected bulk melt beads to thermogravimetric analysis and monitored the evolving volatiles with a quadrupole mass spectrometer. CO2 yields were <5 wt%, with typical values in the 2 wt% range; also total CO2 loss is positively correlated with H2O loss, an indication that most of these volatiles derive from the secondary calcite. Also, transparent glasses, considered the most pristine impact melts, yield 100 wt% element totals by EMPA, suggesting complete loss of CO2. The target dolomite decomposed into MgO, CaO, and CO2; the CO2 escaped and the CaO and MgO combined with SiO2 from coexisting quartz and FeO from the impactor to produce the dominant impact melt at Meteor Crater. Although confined to Meteor Crater, these findings are in stark contrast to Osinski et al. (2008) who proposed that melting of carbonates, rather than devolatilization, is the dominant process during hypervelocity impact into carbonate-bearing targets, including Meteor Crater.

  1. Meteor Crater: An Analog for Using Landforms to Reconstruct Past Hydrologic Conditions

    NASA Astrophysics Data System (ADS)

    Palucis, M. C.; Dietrich, W. E.; Howard, A. D.; Nishiizumi, K.; Caffee, M. W.; Kring, D. A.

    2015-12-01

    Recent work suggests that debris flow activity has occurred on Mars in the last few million years during high orbital obliquities, but estimating the amount and frequency of liquid water needed to generate these types of flows is still poorly constrained. While it is relatively common to estimate water amounts needed to produce landforms on Mars, such as gullies or alluvial fans, this is something rarely done on Earth. Consequently, there is little field data on the linkage between climate (snowmelt or rainfall events) and the amount of runoff needed to produce specific volumes of sediment in a landform. Here, we present field and modeling data from Meteor Crater, which is a ~50,000 year old impact crater in northern Arizona (USA). Though it is very well preserved, it has developed gullies along its inner wall, similar in form to many gullies on Mars. Meteor Crater, similar to many Martian craters, has also gone through a change in a climate based on the ~30 m of lake sediments on its now dry floor, and what has eroded from its walls has deposited on its floor, making it a closed system. We show using LiDAR-derived topographic data and field observations that debris flows, likely generated by runoff entrainment into talus bordering bedrock cliffs of the crater walls, drove erosion and deposition processes at Meteor Crater. Cosmogenic dating of levee deposits indicates that debris flows ceased in the early Holocene, synchronous with regional drying. For a water-to-rock ratio of 0.3 at the time of transport, which is based on data from rotating drum experiments, it would have taken ~150,000 m3 of water to transport the estimated ~500,000 m3 of debris flow deposits found at the surface of the crater floor. This extensive erosion would require less than 0.4 m of total runoff over the 0.35 km2 upslope source area of the crater, or ~26 mm of runoff per debris flow event. Much more runoff did occur however, as evidenced by lake deposits on the crater floor and Holocene

  2. Katabatically Driven Downslope Windstorm-Type Flows on the Inner Sidewall of Arizona's Barringer Meteorite Crater

    NASA Astrophysics Data System (ADS)

    Whiteman, C. D.; Lehner, M.; Hoch, S.; Hills, M.; Haiden, T.; Feigenwinter, I.; Grudzielanek, M.; Maric, M.; Kalthoff, N.; Vogt, R.; Cermak, J.; Rotunno, R.; Calhoun, R.; Cherukuru, N.; Adler, B.

    2015-12-01

    The second Meteor Crater Experiment (METCRAX II) conducted in October 2013 at Arizona's Barringer Meteorite Crater investigated hydraulic-analogue atmospheric flows that cascade into the crater basin over its southwest rim. These intruding downslope windstorm-type flows are produced when the depth of the temperature inversion and accompanying southwesterly downslope flow on the surrounding gently sloping plain exceeds the height of the crater rim. As the southwesterly katabatic flow approaches the crater it decelerates, splits around the crater at elevations below the crater rim, and cascades over the crater rim at upper elevations. The intruding cold katabatic air accelerates down the inner sidewall of the crater, perturbing the prexisting shallow inversion on the crater floor, sometimes creating the atmospheric equivalent of ocean or lake basin seiches. When the cold air intrusions are strong, warm air is brought down into the crater from the upwind atmosphere above the mesoscale inversion, and hydraulic jumps may form on the southwest side of the crater while leaving the rest of the crater atmosphere relatively undisturbed. In this talk, evidence for these flow features will be presented, featuring dual Doppler and time-lapse IR animations of the intruding flows.

  3. Meteor Crater: Energy of formation - Implications of centrifuge scaling

    NASA Technical Reports Server (NTRS)

    Schmidt, R. M.

    1980-01-01

    Recent work on explosive cratering has demonstrated the utility of performing subscale experiments on a geotechnic centrifuge to develop scaling rules for very large energy events. The present investigation is concerned with an extension of this technique to impact cratering. Experiments have been performed using a projectile gun mounted directly on the centrifuge rotor to launch projectiles into a suitable soil container undergoing centripetal accelerations in excess of 500 G. The pump tube of a two-stage light-gas gun was used to attain impact velocities of approximately 2 km/sec. The results of the experiments indicate that the energy of formation of any large impact crater depends upon the impact velocity. This dependence, shown for the case of Meteor Crater, is consistent with analogous results for the specific energy dependence of explosives and is expected to persist to impact velocities in excess of 25 km/sec.

  4. Fractal Fragmentation triggered by meteor impact: The Ries Crater (Germany)

    NASA Astrophysics Data System (ADS)

    Paredes Marino, Joali; Perugini, Diego; Rossi, Stefano; Kueppers, Ulrich

    2015-04-01

    FRACTAL FRAGMENTATION TRIGGERED BY METEOR IMPACT: THE RIES CRATER (GERMANY) Joali Paredes (1), Stefano Rossi (1), Diego Perugini (1), Ulrich Kueppers (2) 1. Department of Physics and Geology, University of Perugia, Italy 2. Department of Earth and Environmental Sciences, University of Munich, Germany The Nördlinger Ries is a large circular depression in western Bavaria, Germany. The depression was caused by a meteor impact, which occurred about 14.3 million-14.5 million years ago. The original crater rim had an estimated diameter of 24 kilometers. Computer modeling of the impact event indicates that the impact or probably had diameters of about 1.5 kilometers and impacted the target area at an angle around 30 to 50 degrees from the surface in a west- southwest to east-northeast direction. The impact velocity is thought to have been about 20 km/s. The meteor impact generated extensive fragmentation of preexisting rocks. In addition, melting of these rocks also occurred. The impact melt was ejected at high speed provoking its extensive fragmentation. Quenched melt fragments are ubiquitous in the outcrops. Here we study melt fragment size distributions with the aim of understanding the style of melt fragmentation during ejection and to constrain the rheological properties of such melts. Digital images of suevite (i.e. the rock generated after deposition and diagenesis of ash and fragments produced by the meteor impact) were obtained using a high-resolution optical scanner. Successively, melt fragments were traced by image analysis and the images segmented in order to obtain binary images on which impact melt fragments are in black color, embedded on a white background. Hence, the size of fragments was determined by image analysis. Fractal fragmentation theory has been applied to fragment size distributions of melt fragments in the Ries crater. Results indicate that melt fragments follow fractal distributions indicating that fragmentation of melt generated by the

  5. Extensional Faulting of the Overturned Coconino Ejecta Layer and Emplacement of Fallback Breccia at Barringer Meteorite Crater (aka Meteor Crater)

    NASA Astrophysics Data System (ADS)

    Kring, D. A.; Cole, S.; Craft, K.; Crites, S.; Gaither, T.; Jilly, C.; Lemelin, M.; Rosenburg, M.; Seward, L.; Song, E.; Snape, J. F.; Talpe, M.; Thaisen, K.; Veto, M.; Wielicki, M.; Williams, F.; Worsham, E.; Garber, J.

    2012-03-01

    New sections measured at Meteor Crater indicate the extension of the ejecta blanket was partly accommodated by a series of normal faults. Those normal faults also provided a means of "burying" and protecting fallback ejecta.

  6. Creation of High Resolution Terrain Models of Barringer Meteorite Crater (Meteor Crater) Using Photogrammetry and Terrestrial Laser Scanning Methods

    NASA Technical Reports Server (NTRS)

    Brown, Richard B.; Navard, Andrew R.; Holland, Donald E.; McKellip, Rodney D.; Brannon, David P.

    2010-01-01

    Barringer Meteorite Crater or Meteor Crater, AZ, has been a site of high interest for lunar and Mars analog crater and terrain studies since the early days of the Apollo-Saturn program. It continues to be a site of exceptional interest to lunar, Mars, and other planetary crater and impact analog studies because of its relatively young age (est. 50 thousand years) and well-preserved structure. High resolution (2 meter to 1 decimeter) digital terrain models of Meteor Crater in whole or in part were created at NASA Stennis Space Center to support several lunar surface analog modeling activities using photogrammetric and ground based laser scanning techniques. The dataset created by this activity provides new and highly accurate 3D models of the inside slope of the crater as well as the downslope rock distribution of the western ejecta field. The data are presented to the science community for possible use in furthering studies of Meteor Crater and impact craters in general as well as its current near term lunar exploration use in providing a beneficial test model for lunar surface analog modeling and surface operation studies.

  7. Formation of the central uplift in meteoric craters

    NASA Technical Reports Server (NTRS)

    Ivanov, B. A.; Bazilevskiy, A. T.; Sazonova, L. V.

    1986-01-01

    Data are presented on the sizes of impact craters with central uplifts on the earth, moon, and terrestrial planets. It is proposed that the central uplift of the Kara crater in the USSR was formed by impact metamorphism of rocks along a crater having a depth of about 600 meters. A theoretical analysis of the mechanics of hypervelocity impact cratering is used to investigate the features of shock-wave attenuation in the depths of the target and the amount of impact melt formed during this process. An attempt is made to determine the velocity of rock motion during the formation of central uplifts in terrestrial craters.

  8. Meteor storm evidence against the recent formation of lunar crater Giordano Bruno

    NASA Astrophysics Data System (ADS)

    Withers, Paul

    2001-04-01

    It has been suggested that the formation of the 22 km diameter lunar crater Giordano Bruno was witnessed in June 1178 A.D. To date, this hypothesis has not been well tested. Such an impact on the Earth would be "civilization threatening". Previous studies have shown that the formation of Giordano Bruno would lead to the arrival of 10 million tonnes of ejecta in the Earth's atmosphere in the following week. I calculate that this would cause a week-long meteor storm potentially comparable to the peak of the 1966 Leonids storm. The lack of any known historical records of such a storm is evidence against the recent formation of Giordano Bruno. Other tests of the hypothesis are also discussed, with emphasis on the lack of corroborating evidence for a very recent formation of the crater.

  9. High Resolution Magnetic and Gravity Surveys to Constrain Maar Geometry and Eruption Mechanisms, Rattlesnake Crater, Arizona

    NASA Astrophysics Data System (ADS)

    Marshall, A. M.; Kruse, S. E.; Connor, C.; Connor, L.; Abdollahzadeh, M.; Harburger, A.; Richardson, J. A.; Courtland, L. M.; Farrell, A. K.; Kiflu, H. G.; Malservisi, R.; McNiff, C. M.; Njoroge, M.; Nushart, N.; Rookey, K.

    2013-12-01

    Located 25 kilometers east of Flagstaff, Arizona, Rattlesnake Crater is an oblong phreatomagmatic feature in the San Francisco Volcanic Field. The shallow crater is approximately 1.4 kilometers at its widest point, and surrounded by an uneven tuff ring which is overlapped by a scoria cone volcano on the southeastern side. Improved understanding of its formation and evolution requires geophysical study because there are very few outcrops, and no digging is permitted on site. Geologic features related to the crater are further obscured by deposits from the overlapping scoria cone, as well as tephra from eruptions at nearby Sunset Crater. We present the results of a detailed magnetic and gravity survey in and around Rattlesnake Crater. A substantial NW-SE trending elongate magnetic anomaly (1400 nT) and a smaller similarly trending anomaly are observed inside the crater, as well as a longer wavelength positive gravitational anomaly (+1.0-1.5 mGal) across the crater. The magnetic survey was completed on foot with a 50 meter line spacing inside the crater, and 100 meter line spacing across a portion of the surrounding area outside the crater. The gravity survey was done on two intersecting survey lines - one running west to east, and another roughly north to south, with recordings every 100 meters extending at least 1000 meters outside the crater in all four directions. 2D models of the magnetic and gravity data are presented illustrating the possible geometry of the diatreme, and the approximate size and shape of the major intrusive features. Eruption estimates based on the models are calculated, and the models are favorably compared to the size and depth estimates given in a recent publication (Valentine 2012) that used xenolith content to estimate the size and depth of the diatreme.

  10. Impact melt- and projectile-bearing ejecta at Barringer Crater, Arizona

    NASA Astrophysics Data System (ADS)

    Osinski, Gordon R.; Bunch, Ted E.; Flemming, Roberta L.; Buitenhuis, Eric; Wittke, James H.

    2015-12-01

    Our understanding of the impact cratering process continues to evolve and, even at well-known and well-studied structures, there is still much to be learned. Here, we present the results of a study on impact-generated melt phases within ejecta at Barringer Crater, Arizona, one of the first impact craters on Earth to be recognized and arguably the most famous. We report on previously unknown impact melt-bearing breccias that contain dispersed fragments of the projectile as well as impact glasses that contain a high proportion of projectile material - higher than any other glasses previously reported from this site. These glasses are distinctly different from so-called ;melt beads; that are found as a lag deposit on the present-day erosion surface and that we also study. It is proposed that the melts in these impact breccias were derived from a more constrained sub-region of the melt zone that was very shallow and that also had a larger projectile contribution. In addition to low- and high-Fe melt beads documented previously, we document Ca-Mg-rich glasses and calcite globules within silicate glass that provide definitive evidence that carbonates underwent melting during the formation of Barringer Crater. We propose that the melting of dolomite produces Ca-Mg-rich melts from which calcite is the dominant liquidus phase. This explains the perhaps surprising finding that despite dolomite being the dominant rock type at many impact sites, including Barringer Crater, calcite is the dominant melt product. When taken together with our estimate for the amount of impact melt products dispersed on, and just below, the present-day erosional surface, it is clear that the amount of melt produced at Barringer Crater is higher than previously estimated and is more consistent with recent numerical modeling studies. This work adds to the growing recognition that sedimentary rocks melt during hypervelocity impact and do not just decompose and/or devolatilize as was previously thought

  11. Turkish meteor surveillance systems and network: Impact craters and meteorites database

    NASA Astrophysics Data System (ADS)

    Unsalan, O.; Ozel, M. E.; Derman, I. E.; Terzioglu, Z.; Kaygisiz, E.; Temel, T.; Topoyan, D.; Solmaz, A.; Yilmaz Kocahan, O.; Esenoglu, H. H.; Emrahoglu, N.; Yilmaz, A.; Yalcinkaya, B. O.

    2014-07-01

    In our project, we aim toward constructing Turkish Meteor Surveillance Systems and Network in Turkey. For this goal, video observational systems from SonotaCo (Japan) were chosen. Meteors are going to be observed with the specific cameras, their orbits will be calculated by the software from SonotaCo, and the places where they will be falling / impacting will be examined by field trips. The collected meteorites will be investigated by IR-Raman Spectroscopic techniques and SEM-EDX analyses in order to setup a database. On the other hand, according to our Prime Ministry Ottoman Archives, there are huge amounts of reports of falls for the past centuries. In order to treat these data properly, it is obvious that processing systems should be constructed and developed.

  12. Doublet Crater

    NASA Image and Video Library

    2010-12-22

    This image from NASA Mars Odyssey is of a doublet crater located in Utopia Planitia, near the Elysium Volcanic region. Doublet craters are formed by simultaneous impact of a meteor that broke into two pieces prior to hitting the surface.

  13. 'Big Crater' in 360-degree panorama

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crater dubbed 'Big Crater', approximately 2200 meters (7200 feet)away was imaged by the Imager for Mars Pathfinder (IMP) as part of a 360-degree color panorama, taken over sols 8, 9 and 10. 'Big Crater' is actually a relatively small Martian crater to the southeast of the Mars Pathfinder landing site. It is 1500 meters (4900 feet) in diameter, or about the same size as Meteor Crater in Arizona.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  14. Measurement of airborne particle concentrations near the Sunset Crater volcano, Arizona.

    PubMed

    Benke, Roland R; Hooper, Donald M; Durham, James S; Bannon, Donald R; Compton, Keith L; Necsoiu, Marius; McGinnis, Ronald N

    2009-02-01

    Direct measurements of airborne particle mass concentrations or mass loads are often used to estimate health effects from the inhalation of resuspended contaminated soil. Airborne particle mass concentrations were measured using a personal sampler under a variety of surface-disturbing activities within different depositional environments at both volcanic and nonvolcanic sites near the Sunset Crater volcano in northern Arizona. Focused field investigations were performed at this analog site to improve the understanding of natural and human-induced processes at Yucca Mountain, Nevada. The level of surface-disturbing activity was found to be the most influential factor affecting the measured airborne particle concentrations, which increased over three orders of magnitude relative to ambient conditions. As the surface-disturbing activity level increased, the particle size distribution and the majority of airborne particle mass shifted from particles with aerodynamic diameters less than 10 mum (0.00039 in) to particles with aerodynamic diameters greater than 10 mum (0.00039 in). Under ambient conditions, above average wind speeds tended to increase airborne particle concentrations. In contrast, stronger winds tended to decrease airborne particle concentrations in the breathing zone during light and heavy surface-disturbing conditions. A slight increase in the average airborne particle concentration during ambient conditions was found above older nonvolcanic deposits, which tended to be finer grained than the Sunset Crater tephra deposits. An increased airborne particle concentration was realized when walking on an extremely fine-grained deposit, but the sensitivity of airborne particle concentrations to the resuspendible fraction of near-surface grain mass was not conclusive in the field setting when human activities disturbed the bulk of near-surface material. Although the limited sample size precluded detailed statistical analysis, the differences in airborne particle

  15. Impact Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    Today marks the 45th anniversary of the dawn of the Space Age (October 4, 1957). On this date the former Soviet Union launched the world's first satellite, Sputnik 1. Sputnik means fellow traveler. For comparison Sputnik 1 weighed only 83.6 kg (184 pounds) while Mars Odyssey weighs in at 758 kg (1,671 pounds).

    This scene shows several interesting geologic features associated with impact craters on Mars. The continuous lobes of material that make up the ejecta blanket of the large impact crater are evidence that the crater ejecta were fluidized upon impact of the meteor that formed the crater. Volatiles within the surface mixed with the ejecta upon impact thus creating the fluidized form. Several smaller impact craters are also observed within the ejecta blanket of the larger impact crater giving a relative timing of events. Layering of geologic units is also observed within the large impact crater walls and floor and may represent different compositional units that erode at variable rates. Cliff faces, dissected gullies, and heavily eroded impact craters are observed in the bottom half of the image at the terminus of a flat-topped plateau.

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

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS

  16. Flagstaff, Arizona seen in Earth Resources Experiments package

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A spectacular winter view of the Flagstaff, Arizona area is seen in this Skylab 4 Earth Resources Experiments package S190-B (five-inch earth terrain camera) infrared photograph taken from the Skylab space station in Earth orbit. Included in the scene are the San Francisco Mountains, Oak Creek Canyon, Painted Desert and Meteor Crater. The infrared picture depicts in red living vegetation, in white the snow, and in bright blue the water. Major features identified in this photograph are Humphrey's peak, top center, Flagstaff at foot of the peak, Sunset Crater volcanic field with numerous vents and craters right of Flagstaff and Meteor Crater (right center). Within the mountainous areas several clear areas generally rectangular are visible and represent the areas where lumbering has removed the forest. The thin white line extending from left corner to Sunset Crater fields is the power transmission line cleared area. Roads are subdued and are not easily visible.

  17. Tephra Blanket Record of a Violent Strombolian Eruption, Sunset Crater, Arizona

    NASA Astrophysics Data System (ADS)

    Wagner, K. D.; Ort, M. H.

    2015-12-01

    New fieldwork provides a detailed description of the widespread tephra of the ~1085 CE Sunset Crater eruption in the San Francisco Volcanic Field, Arizona, and refines interpretation of the eruptive sequence. The basal fine-lapilli tephra-fall-units I-IV are considered in detail. Units I and II are massive, with Unit I composed of angular to spiny clasts and II composed of more equant, oxidized clasts. Units III and IV have inversely graded bases and massive tops and are composed of angular to spiny iridescent and mixed iridescent and oxidized angular clasts, respectively. Xenoliths are rare in all units (<0.1%): sedimentary xenoliths are consistent with the known shallow country rock (Moenkopi and Kaibab Fms); magmatic xenoliths are pumiceous rhyolite mingled with basalt. Unit II is less sideromelane rich (20%) than Units I, III, and IV (60-80%). Above these units are at least two more coarse tephra-fall units. Variably preserved ash and fine-lapilli laminae cap the tephra blanket. This deposit is highly susceptible to reworking, and likely experienced both syn- and post-eruptive aeolian redistribution. It appears as either well sorted, alternating planar-parallel beds of ash and fine lapilli with rare wavy beds, or as cross- or planar-bedded ash. The tephra blanket as a whole is stratigraphically underlain by a fissure-fed lava flow and lapilli-fall units are intercalated with two larger flows. Mean grain size is coarsest in Unit I but coarsens in Units II-IV. Units I, III, and IV are moderately to poorly sorted with no skew. Unit II is better sorted and more coarse-skewed. Units I and III are slightly more platykurtic than II and IV. Without considering possible spatial effects introduced by dispersion patterns, bootstrap ANOVA confidence intervals suggest at least Unit II sorting and skewness are from distinct populations. Isopachs indicate Units I and II were associated with a 10-km-long fissure source. After or during Unit II's deposition, activity localized

  18. Crater

    NASA Image and Video Library

    2015-02-13

    This image captured by NASA 2001 Mars Odyssey spacecraft shows an example of a central peak crater. This unnamed crater is located on the floor of Newton Crater in Terra Sirenum. Orbit Number: 57962 Latitude: -42.1211 Longitude: 201.814 Instrument: VIS Captured: 2015-01-07 07:47 photojournal.jpl.nasa.gov/catalog/PIA19200

  19. Degradation of selected terrestrial and Martian impact craters

    NASA Astrophysics Data System (ADS)

    Grant, J. A.; Schultz, P. H.

    1993-06-01

    The history of degradation of 50,000-yr-old 1.2-km-diam Meteor Crater in Arizona is defined using field mapping, and the degradation states of the progressively more degraded 68,000-yr-old 1.8-km-diam Lonar Crater in Indiana and 0.5-3.0 Myr old 1.75-km-diam Talemzane Crater in Algeria are assessed using air photos. The results on these terrestrial craters are then compared with the gradational morphology associated with craters in southern Ismenius Lacus on Mars, in order to develop first-order constraints on gradational activity. Common degradation signatures associated with craters on both planets are described. These signatures are used to assemble a first-order degradational sequence for the terrestrial craters that is then compared with the Martian degradational signatures to infer past processes and climate.

  20. Impact Crater in Coastal Patagonia

    NASA Technical Reports Server (NTRS)

    D'Antoni, Hector L; Lasta, Carlos A.; Condon, Estelle (Technical Monitor)

    2000-01-01

    Impact craters are geological structures attributed to the impact of a meteoroid on the Earth's (or other planet's) surface (Koeberl and Sharpton. 1999). The inner planets of the solar system as well as other bodies such as our moon show extensive meteoroid impacts (Gallant 1964, French 1998). Because of its size and gravity, we may assume that the Earth has been heavily bombarded but weathering and erosion have erased or masked most of these features. In the 1920's, a meteor crater (Mark 1987) was identified in Arizona and to this first finding the identification of a large number of impact structures on Earth followed (Hodge 1994). Shock metamorphic effects are associated with meteorite impact craters. Due to extremely high pressures, shatter cones are produced as well as planar features in quartz and feldspar grains, diaplectic glass and high-pressure mineral phases such as stishovite (French 1998).

  1. A Young, Fresh Crater in Hellespontus

    NASA Image and Video Library

    2016-01-14

    This image from NASA Mars Reconnaissance Orbiter spacecraft is of a morphologically fresh and simple impact crater in the Hellespontus region. At 1.3 kilometers in diameter, this unnamed crater is only slightly larger than Arizona's Barringer (aka Meteor) Crater, by about 200 meters. Note the simple bowl shape and the raised crater rim. Rock and soil excavated out of the crater by the impacting meteor -- called ejecta -- forms the ejecta deposit. It is continuous for about one crater radius away from the rim and is likely composed of about 90 percent ejecta and 10 percent in-place material that was re-worked by both the impact and the subsequently sliding ejecta. The discontinuous ejecta deposit extends from about one crater radius outward. Here, high velocity ejecta that was launched from close to the impact point -- and got the biggest kick -- flew a long way, landed, rolled, slid, and scoured the ground, forming long tendrils of ejecta and v-shaped ridges. http://photojournal.jpl.nasa.gov/catalog/PIA20340

  2. Filled Craters

    NASA Image and Video Library

    2006-05-11

    This MOC image shows adjacent impact craters located north-northwest of the Acheron Fossae region of Mars. The two craters are of similar size and formed by meteor impacts. However, one is much more filled than the other, indicating that it is older

  3. Meteor Showers.

    ERIC Educational Resources Information Center

    Kronk, Gary W.

    1988-01-01

    Described are the history, formation, and observing techniques of meteors and comets. Provided are several pictures, diagrams, meteor organizations and publications, and meteor shower observation tables. (YP)

  4. Meteor Showers.

    ERIC Educational Resources Information Center

    Kronk, Gary W.

    1988-01-01

    Described are the history, formation, and observing techniques of meteors and comets. Provided are several pictures, diagrams, meteor organizations and publications, and meteor shower observation tables. (YP)

  5. Crater

    NASA Image and Video Library

    2015-09-03

    This relatively young crater is located on the northern plains of Arcadia Planitia. Orbit Number: 60388 Latitude: 61.6777 Longitude: 228.91 Instrument: VIS Captured: 2015-07-26 03:01 http://photojournal.jpl.nasa.gov/catalog/PIA19766

  6. Small Gullied Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    18 November 2004 Middle- and polar-latitude martian gullies remain as much a mystery today as they were when first announced in June 2000. Some have argued that they form by running water, others argue they required carbon dioxide in liquid or gas form, still others have proposed that these features form 'dry' by simple landsliding processes (although landslides elsewhere on Mars do not form features that look like the martian gullies). They occur almost exclusively at latitudes higher than 30o in both hemispheres, although they are more common in the southern hemisphere. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a very small gully example in a crater that is only about 1 km across -- roughly the size of the famous Meteor Crater in northern Arizona. The debris transported through the gullies was deposited on top of light-toned, windblown ripples on the floor of the crater, indicating that the ripples are older. This crater is located near 37.9oS, 169.3oW. The 150 meter scale bar is about 490 feet long. Sunlight illuminates the scene from the upper left.

  7. Scoria Cone and Tuff Ring Stratigraphy Interpreted from Ground Penetrating Radar, Rattlesnake Crater, Arizona

    NASA Astrophysics Data System (ADS)

    Kruse, S. E.; McNiff, C. M.; Marshall, A. M.; Courtland, L. M.; Connor, C.; Charbonnier, S. J.; Abdollahzadeh, M.; Connor, L.; Farrell, A. K.; Harburger, A.; Kiflu, H. G.; Malservisi, R.; Njoroge, M.; Nushart, N.; Richardson, J. A.; Rookey, K.

    2013-12-01

    Numerous recent studies have demonstrated that detailed investigation of scoria cone and maar morphology can reveal rich details the eruptive and erosion histories of these volcanoes. A suite of geophysical surveys were conducted to images Rattlesnake Crater in the San Francisco Volcanic Field, AZ, US. We report here the results of ~3.4 km of ground penetrating radar (GPR) surveys that target the processes of deposition and erosion on the pair of cinder cones that overprint the southeast edge of Rattlesnake crater and on the tuff ring that forms the crater rim. Data were collected with 500, 250, 100, and 50 MHz antennas. The profiles were run in a radial direction down the northeast flanks of the cones (~1 km diameter, ~120 meters height) , and on the inner and outer margins of the oblong maar rim (~20-80 meters height). A maximum depth of penetration of GPR signal of ~15m was achieved high on the flanks of scoria cones. A minimum depth of essentially zero penetration occurred in the central crater. We speculate that maximum penetration occurs near the peaks of the cones and crater rim because ongoing erosion limits new soil formation. Soil formation would tend to increase surface conductivity and hence decrease GPR penetration. Soil is probably better developed within the crater, precluding significant radar penetration there. On the northeast side of the gently flattened rim of the easternmost scoria cone, the GPR profile shows internal layering that dips ~20 degrees northeast relative to the current ground surface. This clearly indicates that the current gently dipping surface is not a stratigraphic horizon, but reflects instead an erosive surface into cone strata that formed close to the angle of repose. Along much of the cone flanks GPR profiles show strata dipping ~4-5 degrees more steeply than the current surface, suggesting erosion has occurred over most of the height of the cone. An abrupt change in strata attitude is observed at the gradual slope

  8. Fluidized crater ejecta

    NASA Image and Video Library

    2002-12-13

    The ejecta blanket of the crater in this image from NASA Mars Odyssey spacecraft does not resemble the blocky, discontinuous ejecta associated with most fresh craters on Mars. Rather, the continuous lobes of material seen around this crater are evidence that the crater ejecta were fluidized upon impact of the meteor that formed this crater. Impact ejecta become fluidized when a meteor strikes a surface that has a considerable volatile content. The volatiles mixed with the ejecta form a flow of material that moves outward from the crater and produces the morphology seen in this THEMIS visible image. http://photojournal.jpl.nasa.gov/catalog/PIA04025

  9. Exhumed Craters

    NASA Technical Reports Server (NTRS)

    2004-01-01

    5 July 2004 Burial and exhumation is a theme that repeats itself, all over the surface of Mars. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows several north mid-latitude meteor impact craters with bouldery ejecta deposits. Each of the craters was once buried and later exhumed. Mesas on the floors of these craters are remnants of the materials that once filled and covered them. The craters are located near 39.7oN, 206.0oW. The image covers an area about 3 km (1.9 mi) wide; sunlight illuminates the scene from the lower left.

  10. Geochemical and C, O, Sr, and U-series isotopic evidence for the meteoric origin of calcrete at Solitario Wash, Crater Flat, Nevada, USA

    USGS Publications Warehouse

    Neymark, L.A.; Paces, J.B.; Marshall, B.D.; Peterman, Z.E.; Whelan, J.F.

    2005-01-01

    Calcite-rich soils (calcrete) in alluvium and colluvium at Solitario Wash, Crater Flat, Nevada, USA, contain pedogenic calcite and opaline silica similar to soils present elsewhere in the semi-arid southwestern United States. Nevertheless, a ground-water discharge origin for the Solitario Wash soil deposits was proposed in a series of publications proposing elevation-dependent variations of carbon and oxygen isotopes in calcrete samples. Discharge of ground water in the past would raise the possibility of future flooding in the unsaturated zone at Yucca Mountain, Nevada, site of a proposed high-level nuclear waste repository. New geochemical and carbon, oxygen, strontium, and uranium-series isotopic data disprove the presence of systematic elevation-isotopic composition relations, which are the main justification given for a proposed ground-water discharge origin of the calcrete deposits at Solitario Wash. Values of ??13C (-4.1 to -7.8 per mil [???]), ??18O (23.8-17.2???), 87Sr/ 86Sr (0.71270-0.71146), and initial 234U/238U activity ratios of about 1.6 in the new calcrete samples are within ranges previously observed in pedogenic carbonate deposits at Yucca Mountain and are incompatible with a ground-water origin for the calcrete. Variations in carbon and oxygen isotopes in Solitario Wash calcrete likely are caused by pedogenic deposition from meteoric water under varying Quaternary climatic conditions over hundreds of thousands of years. ?? Springer-Verlag 2005.

  11. Subsurface structure of a maar-diatreme and associated tuff ring from a high-resolution geophysical survey, Rattlesnake Crater, Arizona

    NASA Astrophysics Data System (ADS)

    Marshall, Anita; Connor, Charles; Kruse, Sarah; Malservisi, Rocco; Richardson, Jacob; Courtland, Leah; Connor, Laura; Wilson, James; Karegar, Makan A.

    2015-10-01

    Geophysical survey techniques including gravity, magnetics, and ground penetrating radar were utilized to study the diatreme and tuff ring at Rattlesnake Crater, a maar in the San Francisco Volcanic Field of northern Arizona. Significant magnetic anomalies (+ 1600 nT) and a positive gravity anomaly (+ 1.4 mGal) are associated with the maar. Joint modeling of magnetic and gravity data indicate that the diatreme that underlies Rattlesnake Crater has volume of 0.8-1 km3, and extends to at least 800 m depth. The modeled diatreme comprises at least two zones of variable density and magnetization, including a low density, highly magnetized unit near the center of the diatreme, interpreted to be a pyroclastic unit emplaced at sufficiently high temperature and containing sufficient juvenile fraction to acquire thermal remanent magnetization. Magnetic anomalies and ground penetrating radar (GPR) imaging demonstrate that the bedded pyroclastic deposits of the tuff ring also carry high magnetization, likely produced by energetic emplacement of hot pyroclastic density currents. GPR profiles on the tuff ring reveal long (~ 100 m) wavelength undulations in bedding planes. Elsewhere, comparable bedforms have been interpreted as base surge deposits inflated by air entrainment from eruption column collapse. Interpretation of these geophysical data suggests that Rattlesnake Crater produced highly energetic phreatomagmatic activity that gave way to less explosive activity as the eruption progressed. The positive gravity anomaly associated with the maar crater is interpreted to be caused by coherent bodies within the diatreme and possibly lava ponding on the crater floor. These dense magnetized bodies have excess mass of 2-4 × 1010 kg, and occupy approximately 5% of the diatreme by volume. Magnetic anomalies on the crater floor are elongate NW-SE, suggesting that the eruption may have been triggered by the interaction of ascending magma with water in fractures of this orientation

  12. Layers and Boulders in Crater Wall, Nepenthes Mensae Region

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Peering down into craters offers Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) scientists an opportunity to examine one of the few landforms that Mars shares in common with the other planets and moons of our Solar System.

    The picture on the left (above) is a MOC context frame taken at the same time as the MOC high resolution image on the right. The white box on the left shows the location of the high resolution view. The high resolution image was targeted on a 3 kilometers (1.9 miles) wide impact crater on the floor of a larger crater in the Nepenthes Mensae region (near 3oS, 239oW). The context image is about 115 km (71 mi) across, the high-resolution image is 3 km (1.9 mi) across, and both are illuminated from the left/lower left.

    The 3 km diameter crater in the MOC image on the right is three times wider than the famous Meteor Crater in northern Arizona, USA. The high resolution image shows many small windblown drifts or dunes in the low areas both within the crater and outside on the surrounding terrain. Some portions of the crater's walls exhibit outcrops of bare, layered rock. Large boulders have been dislodged from the walls and have tumbled down the slopes to the crater floor. Many of these boulders are bigger than school buses and automobiles.

  13. Flagstaff, Arizona seen in Earth Resources Experiments package

    NASA Image and Video Library

    1974-02-01

    SL4-93-067 (16 Nov. 1973-8 Feb. 1974) --- A spectacular winter view of the Flagstaff, Arizona area is seen in this Skylab 4 Earth Resources Experiments package S190-B (five-inch earth terrain camera) infrared photograph taken from the Skylab space station in Earth orbit. Included in the scene are the San Francisco Mountains, Oak Creek Canyon, Painted Desert and Meteor Crater. The infrared picture depicts in red living vegetation, in white the snow, and in bright blue the water. Major features identified in this photograph are Humphrey's peak, top center, Flagstaff at foot of the peak, Sunset Crater volcanic field with numerous vents and craters right of Flagstaff and Meteor Crater (right center). Within the mountainous areas several clear areas generally rectangular are visible and represent the areas where lumbering has removed the forest. The thin white line extending from left corner to Sunset Crater fields is the power transmission line cleared area. Roads are subdued and are not easily visible. Photo credit: NASA

  14. Big Crater as Viewed by Pathfinder Lander

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The 'Big Crater' is actually a relatively small Martian crater to the southeast of the Mars Pathfinder landing site. It is 1500 meters (4900 feet) in diameter, or about the same size as Meteor Crater in Arizona. Superimposed on the rim of Big Crater (the central part of the rim as seen here) is a smaller crater nicknamed 'Rimshot Crater.' The distance to this smaller crater, and the nearest portion of the rim of Big Crater, is 2200 meters (7200 feet). To the right of Big Crater, south from the spacecraft, almost lost in the atmospheric dust 'haze,' is the large streamlined mountain nicknamed 'Far Knob.' This mountain is over 450 meters (1480 feet) tall, and is over 30 kilometers (19 miles) from the spacecraft. Another, smaller and closer knob, nicknamed 'Southeast Knob' can be seen as a triangular peak to the left of the flanks of the Big Crater rim. This knob is 21 kilometers (13 miles) southeast from the spacecraft.

    The larger features visible in this scene - Big Crater, Far Knob, and Southeast Knob - were discovered on the first panoramas taken by the IMP camera on the 4th of July, 1997, and subsequently identified in Viking Orbiter images taken over 20 years ago. The scene includes rocky ridges and swales or 'hummocks' of flood debris that range from a few tens of meters away from the lander to the distance of South Twin Peak. The largest rock in the nearfield, just left of center in the foreground, nicknamed 'Otter', is about 1.5 meters (4.9 feet) long and 10 meters (33 feet) from the spacecraft.

    This view of Big Crater was produced by combining 6 individual 'Superpan' scenes from the left and right eyes of the IMP camera. Each frame consists of 8 individual frames (left eye) and 7 frames (right eye) taken with different color filters that were enlarged by 500% and then co-added using Adobe Photoshop to produce, in effect, a super-resolution panchromatic frame that is sharper than an individual frame would be.

    Mars Pathfinder is the second in NASA

  15. Big Crater as Viewed by Pathfinder Lander

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The 'Big Crater' is actually a relatively small Martian crater to the southeast of the Mars Pathfinder landing site. It is 1500 meters (4900 feet) in diameter, or about the same size as Meteor Crater in Arizona. Superimposed on the rim of Big Crater (the central part of the rim as seen here) is a smaller crater nicknamed 'Rimshot Crater.' The distance to this smaller crater, and the nearest portion of the rim of Big Crater, is 2200 meters (7200 feet). To the right of Big Crater, south from the spacecraft, almost lost in the atmospheric dust 'haze,' is the large streamlined mountain nicknamed 'Far Knob.' This mountain is over 450 meters (1480 feet) tall, and is over 30 kilometers (19 miles) from the spacecraft. Another, smaller and closer knob, nicknamed 'Southeast Knob' can be seen as a triangular peak to the left of the flanks of the Big Crater rim. This knob is 21 kilometers (13 miles) southeast from the spacecraft.

    The larger features visible in this scene - Big Crater, Far Knob, and Southeast Knob - were discovered on the first panoramas taken by the IMP camera on the 4th of July, 1997, and subsequently identified in Viking Orbiter images taken over 20 years ago. The scene includes rocky ridges and swales or 'hummocks' of flood debris that range from a few tens of meters away from the lander to the distance of South Twin Peak. The largest rock in the nearfield, just left of center in the foreground, nicknamed 'Otter', is about 1.5 meters (4.9 feet) long and 10 meters (33 feet) from the spacecraft.

    This view of Big Crater was produced by combining 6 individual 'Superpan' scenes from the left and right eyes of the IMP camera. Each frame consists of 8 individual frames (left eye) and 7 frames (right eye) taken with different color filters that were enlarged by 500% and then co-added using Adobe Photoshop to produce, in effect, a super-resolution panchromatic frame that is sharper than an individual frame would be.

    Mars Pathfinder is the second in NASA

  16. Craters Filling Craters

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    In today's image the large crater retains its original bowl shaped interior and the radial surface pattern on the ejecta. Just to the south is a crater that has been infilled by ejecta from the larger crater. The overlapping of ejecta blankets can be used to get relative age relationships, in this case the smaller crater to the south formed first, and the larger crater formed sometime later.

    Image information: VIS instrument. Latitude 29.6, Longitude 96.3 East (263.7 West). 37 meter/pixel resolution.

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

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

  17. Henry Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    Located in Arabia Terra, the crater shown here is known as Henry Crater. Like many other craters on Mars, the interior of Henry Crater is filled with a layered deposit. These materials were brought into the crater sometime after the impact formed the crater. The fine scale of layering can be seen in the right- center portion of the image.

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

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

  18. Secrets of the Wabar craters

    USGS Publications Warehouse

    Wynn, Jeffrey C.; Shoemaker, Eugene M.

    1997-01-01

    Focuses on the existence of craters in the Empty Quarter of Saudi Arabia created by the impact of meteors in early times. Mars Pathfinder and Mars Global Surveyor's encounter with impact craters; Elimination of craters in the Earth's surface by the action of natural elements; Impact sites' demand for careful scientific inspections; Location of the impact sites.

  19. Retinal meteor.

    PubMed

    Venkatesh, Ramesh; Gurav, Prachi; Dave, Prachi Abhishek; Roy, Sankhadeep

    2017-09-01

    We describe a case of a 65-year old man diagnosed with retinal vasoproliferative tumour secondary to posterior uveitis. The fluorescein angiography shows an interesting meteor-like leak emanating from the tumour and rising towards the superior retina in the later frames of the angiogram. Pictorially, we call it the "Retinal Meteor" and also describe the possible mechanism for this pattern of leakage.

  20. Meteor44 Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Cooke, William J.

    2004-01-01

    Meteor44 is a software system developed at MSFC for the calibration and analysis of video meteor data. The dynamic range of the (8bit) video data is extended by approximately 4 magnitudes for both meteors and stellar images using saturation compensation. Camera and lens specific saturation compensation coefficients are derived from artificial variable star laboratory measurements. Saturation compensation significantly increases the number of meteors with measured intensity and improves the estimation of meteoroid mass distribution. Astrometry is automated to determine each image's plate coefficient using appropriate star catalogs. The images are simultaneously intensity calibrated from the contained stars to determine the photon sensitivity and the saturation level referenced above the atmosphere. The camera s spectral response is used to compensate for stellar color index and typical meteor spectra in order to report meteor light curves in traditional visual magnitude units. Recent efforts include improved camera calibration procedures, long focal length 'streak' meteor photometry and two-station track determination. Meteor44 has been used to analyze data from the 2001, 2002 and 2003 MSFC Leonid observational campaigns as well as several lesser showers. The software is interactive and can be demonstrated using data from recent Leonid campaigns.

  1. Meteor44 Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Cooke, William J.

    2004-01-01

    Meteor44 is a software system developed at MSFC for the calibration and analysis of video meteor data. The dynamic range of the (8bit) video data is extended by approximately 4 magnitudes for both meteors and stellar images using saturation compensation. Camera and lens specific saturation compensation coefficients are derived from artificial variable star laboratory measurements. Saturation compensation significantly increases the number of meteors with measured intensity and improves the estimation of meteoroid mass distribution. Astrometry is automated to determine each image's plate coefficient using appropriate star catalogs. The images are simultaneously intensity calibrated from the contained stars to determine the photon sensitivity and the saturation level referenced above the atmosphere. The camera s spectral response is used to compensate for stellar color index and typical meteor spectra in order to report meteor light curves in traditional visual magnitude units. Recent efforts include improved camera calibration procedures, long focal length 'streak' meteor photometry and two-station track determination. Meteor44 has been used to analyze data from the 2001, 2002 and 2003 MSFC Leonid observational campaigns as well as several lesser showers. The software is interactive and can be demonstrated using data from recent Leonid campaigns.

  2. Meteor44 Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Cooke, William J.

    2004-01-01

    Meteor44 is a software system developed at MSFC for the calibration and analysis of video meteor data. The dynamic range of the (8bit) video data is extended by approximately 4 magnitudes for both meteors and stellar images using saturation compensation. Camera and lens specific saturation compensation coefficients are derived from artificial variable star laboratory measurements. Saturation compensation significantly increases the number of meteors with measured intensity and improves the estimation of meteoroid mass distribution. Astrometry is automated to determine each image s plate coefficient using appropriate star catalogs. The images are simultaneously intensity calibrated from the contained stars to determine the photon sensitivity and the saturation level referenced above the atmosphere. The camera s spectral response is used to compensate for stellar color index and typical meteor spectra in order to report meteor light curves in traditional visual magnitude units. Recent efforts include improved camera calibration procedures, long focal length "streak" meteor photome&y and two-station track determination. Meteor44 has been used to analyze data from the 2001.2002 and 2003 MSFC Leonid observational campaigns as well as several lesser showers. The software is interactive and can be demonstrated using data from recent Leonid campaigns.

  3. The origin of lunar craters

    NASA Technical Reports Server (NTRS)

    Wegener, A.

    1975-01-01

    A review is presented of four hypotheses concerning the origin of lunar craters, taking into account the bubble hypothesis, the tide hypothesis, the volcanic hypothesis, and the impact hypothesis. A description is given of a series of experiments on impact craters and studies of a meteorite crater in Arizona are considered. It is concluded that the typical lunar craters can best be interpreted as impact craters.

  4. Impact Craters in North America

    NASA Astrophysics Data System (ADS)

    Grieve, R. A. F.; Wood, C. A.; Garvin, J. B.; McLaughlin, G.; McHone, J. F.

    1988-03-01

    Meteor Crater Upheaval Dome Sierra Madera Middlesboro Pilot Lake Carswell Gow Lake Deep Bay Nicholson Lake West Hawk Lake Haughton Sudbury Wanapitei Brent Lac Couture New Quebec Clearwater Lakes Manicouagan Charlevoix Lac La Moinerie Mistastin

  5. Video Meteor Fluxes

    NASA Technical Reports Server (NTRS)

    Campbell-Brown, M. D.; Braid, D.

    2011-01-01

    The flux of meteoroids, or number of meteoroids per unit area per unit time, is critical for calibrating models of meteoroid stream formation and for estimating the hazard to spacecraft from shower and sporadic meteors. Although observations of meteors in the millimetre to centimetre size range are common, flux measurements (particularly for sporadic meteors, which make up the majority of meteoroid flux) are less so. It is necessary to know the collecting area and collection time for a given set of observations, and to correct for observing biases and the sensitivity of the system. Previous measurements of sporadic fluxes are summarized in Figure 1; the values are given as a total number of meteoroids striking the earth in one year to a given limiting mass. The Gr n et al. (1985) flux model is included in the figure for reference. Fluxes for sporadic meteoroids impacting the Earth have been calculated for objects in the centimeter size range using Super-Schmidt observations (Hawkins & Upton, 1958); this study used about 300 meteors, and used only the physical area of overlap of the cameras at 90 km to calculate the flux, corrected for angular speed of meteors, since a large angular speed reduces the maximum brightness of the meteor on the film, and radiant elevation, which takes into account the geometric reduction in flux when the meteors are not perpendicular to the horizontal. They bring up corrections for both partial trails (which tends to increase the collecting area) and incomplete overlap at heights other than 90 km (which tends to decrease it) as effects that will affect the flux, but estimated that the two effects cancelled one another. Halliday et al. (1984) calculated the flux of meteorite-dropping fireballs with fragment masses greater than 50 g, over the physical area of sky accessible to the MORP fireball cameras, counting only observations in clear weather. In the micron size range, LDEF measurements of small craters on spacecraft have been used to

  6. Crater Comparison

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    These two craters show the two types of crater interiors found on Mars -- original and modified. The crater on the right has its original bowl shape. The crater of the left has had its interior modified by an infilling of lava.

    Image information: VIS instrument. Latitude 27.6, Longitude 194.5 East (165.5 West). 37 meter/pixel resolution.

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

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

  7. Impact Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    The fluidized impact crater ejecta and flat crater floors observed in this THEMIS image suggest near surface volatiles once played an important role in modifying the martian surface. Gullies observed in crater walls could possibly point to more recent volatile-rock interactions.

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

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

    Image information: VIS instrument. Latitude 13.9, Longitude 297.3 East (62.7 West). 19 meter/pixel resolution.

  8. Cydonia Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Eroded mesas and secondary craters dot the landscape in this area of the Cydonia Mensae region. The single oval-shaped crater displays a 'butterfly' ejecta pattern, indicating that the crater formed from a low-angle impact.

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

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

    Image information: VIS instrument. Latitude 32.9, Longitude 343.8 East (16.2 West). 19 meter/pixel resolution.

  9. Crater Clouds

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA06085 Crater Clouds

    The crater on the right side of this image is affecting the local wind regime. Note the bright line of clouds streaming off the north rim of the crater.

    Image information: VIS instrument. Latitude -78.8N, Longitude 320.0E. 17 meter/pixel resolution.

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

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

  10. Crater Landslide

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA06088 Crater Landslide

    This landslide occurs in an unnamed crater southeast of Millochau Crater.

    Image information: VIS instrument. Latitude -24.4N, Longitude 87.5E. 17 meter/pixel resolution.

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

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

  11. Crater Landslide

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA06088 Crater Landslide

    This landslide occurs in an unnamed crater southeast of Millochau Crater.

    Image information: VIS instrument. Latitude -24.4N, Longitude 87.5E. 17 meter/pixel resolution.

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

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

  12. Abstracts for the International Conference on Asteroids, Comets, Meteors 1991

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Topics addressed include: chemical abundances; asteroidal belt evolution; sources of meteors and meteorites; cometary spectroscopy; gas diffusion; mathematical models; cometary nuclei; cratering records; imaging techniques; cometary composition; asteroid classification; radio telescopes and spectroscopy; magnetic fields; cosmogony; IUE observations; orbital distribution of asteroids, comets, and meteors; solar wind effects; computerized simulation; infrared remote sensing; optical properties; and orbital evolution.

  13. Scaling craters in carbonates: Electron paramagnetic resonance analysis of shock damage

    NASA Technical Reports Server (NTRS)

    Polanskey, Carol A.; Ahrens, Thomas J.

    1994-01-01

    prehistoric shock damage. This is demonstrated by our study of shocked Kaibab limestone from the 49,000-year-old Meteor (Barringer) Crater Arizona.

  14. Scaling craters in carbonates: Electron paramagnetic resonance analysis of shock damage

    NASA Technical Reports Server (NTRS)

    Polanskey, Carol A.; Ahrens, Thomas J.

    1994-01-01

    prehistoric shock damage. This is demonstrated by our study of shocked Kaibab limestone from the 49,000-year-old Meteor (Barringer) Crater Arizona.

  15. Asteroids, Comets, Meteors 2014

    NASA Astrophysics Data System (ADS)

    Muinonen, K.; Penttilä, A.; Granvik, M.; Virkki, A.; Fedorets, G.; Wilkman, O.; Kohout, T.

    2014-08-01

    Asteroids, Comets, Meteors focuses on the research of small Solar System bodies. Small bodies are the key to understanding the formation and evolution of the Solar System, carrying signals from pre-solar times. Understanding the evolution of the Solar System helps unveil the evolution of extrasolar planetary systems. Societally, small bodies will be important future resources of minerals. The near-Earth population of small bodies continues to pose an impact hazard, whether it be small pieces of falling meteorites or larger asteroids or cometary nuclei capable of causing global environmental effects. The conference series entitled ''Asteroids, Comets, Meteors'' constitutes the leading international series in the field of small Solar System bodies. The first three conferences took place in Uppsala, Sweden in 1983, 1985, and 1989. The conference is now returning to Nordic countries after a quarter of a century. After the Uppsala conferences, the conference has taken place in Flagstaff, Arizona, U.S.A. in 1991, Belgirate, Italy in 1993, Paris, France in 1996, Ithaca, New York, U.S.A. in 1999, in Berlin, Germany in 2002, in Rio de Janeiro, Brazil in 2005, in Baltimore, Maryland, U.S.A. in 2008, and in Niigata, Japan in 2012. ACM in Helsinki, Finland in 2014 will be the 12th conference in the series.

  16. Pedestal Crater and Yardangs

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-444, 6 August 2003

    This April 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small meteor impact crater that has been modified by wind erosion. Two things happened after the crater formed. First, the upper few meters of surface material into which the meteor impacted was later eroded away by wind. The crater ejecta formed a protective armor that kept the material under the ejecta from been blown away. This caused the crater and ejecta to appear as if standing upon a raised platform--a feature that Mars geologists call a pedestal crater. Next, the pedestal crater was buried beneath several meters of new sediment, and then this material was eroded away by wind to form the array of sharp ridges that run across the pedestal crater's surface. These small ridges are known as yardangs. This picture is illuminated by sunlight from the upper left; it is located in west Daedalia Planum near 14.6oS, 131.9oW.

  17. Iturralde Crater, Bolivia

    NASA Image and Video Library

    2002-09-17

    NASA scientists will venture into an isolated part of the Bolivian Amazon to try and uncover the origin of a 5 mile (8 kilometer) diameter crater there known as the Iturralde Crater. Traveling to this inhospitable forest setting, the Iturralde Crater Expedition 2002 will seek to determine if the unusual circular crater was created by a meteor or comet. Organized by Dr. Peter Wasilewski of NASA's Goddard Space Flight Center, Greenbelt, Md., the Iturralde Crater Expedition 2002 will be led by Dr. Tim Killeen of Conservation International, which is based in Bolivia. Killeen will be assisted by Dr. Compton Tucker of Goddard. The team intends to collect and analyze rocks and soil, look for glass particles that develop from meteor impacts and study magnetic properties in the area to determine if the Iturralde site was indeed created by a meteor. This image was acquired on June 29, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet. http://photojournal.jpl.nasa.gov/catalog/PIA03859

  18. Palos Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    Palos Crater has been suggested as a future landing site for Mars Missions. This crater has a channel called Tinto Vallis, which enters from the south. This site was suggested as a landing site because it may contain lake deposits. Palos Crater is named in honor of the port city in Spain from which Christopher Columbus sailed on his way to the New World in August of 1492. The floor of Palos Crater appears to be layered in places providing further evidence that this site may in fact have been the location of an ancient lake.

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

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

  19. Refilled Crater

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The interior of this crater has undergone at least two episodes of modification. At some time the crater interior was filled by material to approximately the high of the crater rim. Then erosion occurs, removing some of the infill but leaving the two plateaus in the center. Finally, the crater has been infilled a second time. The latest fill is lava.

    Image information: VIS instrument. Latitude 13.5, Longitude 284.3 East (75.7 West). 36 meter/pixel resolution.

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

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

  20. Buried Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    With a location roughly equidistant between two of the largest volcanic constructs on the planet, the fate of the 50 km impact crater in this image was sealed. It has been buried to the rim by lava flows. The MOLA context image shows pronounced flow lobes surrounding the crater, a clear indication of the most recent episode of volcanism that could have contributed to its infilling. Breaches in the rim are clearly evident in the image and suggest locations through which lavas could have flowed. These openings appear to be limited to the west side of the crater. Other craters in the area are nearly obliterated by the voluminous lava flows, further demonstrating one of the means by which Mars renews its surface.

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

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

  1. Buried Craters of Utopia

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-365, 19 May 2003

    Beneath the northern plains of Mars are numerous buried meteor impact craters. One of the most heavily-cratered areas, although buried, occurs in Utopia Planitia, as shown in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image. The history of Mars is complex; impact craters provide a tool by which to understand some of that history. In this case, a very ancient, cratered surface was thinly-buried by younger material that is not cratered at all. This area is near 48.1oN, 228.2oW; less than 180 km (112 mi) west of the Viking 2 lander site. Sunlight illuminates the scene from the lower left.

  2. Meteor trajectory estimation from radio meteor observations

    NASA Astrophysics Data System (ADS)

    Kákona, J.

    2016-01-01

    Radio meteor observation techniques are generally accepted as meteor counting methods useful mainly for meteor flux detection. Due to the technical progress in radio engineering and electronics a construction of a radio meteor detection network with software defined receivers has become possible. These receivers could be precisely time synchronized and could obtain data which provide us with more information than just the meteor count. We present a technique which is able to compute a meteor trajectory from the data recorded by multiple radio stations.

  3. The history of meteors and meteor showers

    NASA Astrophysics Data System (ADS)

    Hughes, David W.

    The history of meteors and meteor showers can effectively start with the work of Edmond Halley who overcome the Aristotelean view of meteors as being an upper atmospheric phenomenon and introduced their extraterrestrial nature. Halley also estimated their height and velocity. The observations of the Leonids in 1799, 1833 and 1866 established meteoroids as cometary debris. Two red herrings were caught — fixed radiants and hyperbolic velocities. But the 1890 to 1950 period with two-station meteor photography, meteor spectroscopy and the radar detection of meteors saw the subject well established.

  4. Impact Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    The relatively flat floor and terrace walls of this impact crater suggest the crater was partly infilled with sediment and subsequently eroded to its present day form. This type of observation is evidence for environmental change throughout the geologic history of Mars.

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

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

    Image information: VIS instrument. Latitude 18.1, Longitude 136.3 East (223.7 West). 19 meter/pixel resolution.

  5. Meteor Beliefs Project: ``Year of Meteors''

    NASA Astrophysics Data System (ADS)

    McBeath, Alastair; Drobnock, George J.; Gheorghe, Andrei Dorian

    2011-10-01

    We present a discussion linking ideas from a modern music album by Laura Veirs back to a turbulent time in American history 150 years ago, which inspired poet Walt Whitman to compose his poem "Year of Meteors", and the meteor beliefs of the period around 1859-1860, when collection of facts was giving way to analyses and theoretical explanations in meteor science.

  6. Cutting Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 12 November 2003

    The rims of two old and degraded impact craters are intersected by a graben in this THEMIS image taken near Mangala Fossa. Yardangs and low-albedo wind streaks are observed at the top of the image as well as interesting small grooves on the crater floor. The origin of these enigmatic grooves may be the result of mud or lava and volatile interactions. Variable surface textures observed in the bottom crater floor are the result of different aged lava flows.

    Image information: VIS instrument. Latitude -15.2, Longitude 219.2 East (140.8 West). 19 meter/pixel resolution.

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

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

  7. Unusual Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 15 May 2003

    This unusual crater northeast of Ascraeus Mons displays an ejecta blanket that appears turned up around its edges. This may be a type of rampart crater, or may instead be a crater with its ejecta blanket buried by lava flows. These flows were later eroded away in places leaving behind the scarp. Numerous lava flows are seen in this image as well as sinuous channels. These features appear to be both volcanic (rilles) and fluvial channels.

    Image information: VIS instrument. Latitude 16.8, Longitude 257.4East (102.6). 19 meter/pixel resolution.

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

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

  8. Cutting Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 12 November 2003

    The rims of two old and degraded impact craters are intersected by a graben in this THEMIS image taken near Mangala Fossa. Yardangs and low-albedo wind streaks are observed at the top of the image as well as interesting small grooves on the crater floor. The origin of these enigmatic grooves may be the result of mud or lava and volatile interactions. Variable surface textures observed in the bottom crater floor are the result of different aged lava flows.

    Image information: VIS instrument. Latitude -15.2, Longitude 219.2 East (140.8 West). 19 meter/pixel resolution.

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

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

  9. Evidence for Recent Liquid Water on Mars: Channeled Aprons in a Small Crater within Newton Crater

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    Newton Crater is a large basin formed by an asteroid impact that probably occurred more than 3 billion years ago. It is approximately 287 kilometers (178 miles) across. The picture shown here (top) highlights the north wall of a specific, smaller crater located in the southwestern quarter of Newton Crater (above). The crater of interest was also formed by an impact; it is about 7 km (4.4 mi) across, which is about 7 times bigger than the famous Meteor Crater in northern Arizona in North America.

    The north wall of the small crater has many narrow gullies eroded into it. These are hypothesized to have been formed by flowing water and debris flows. Debris transported with the water created lobed and finger-like deposits at the base of the crater wall where it intersects the floor (bottom center top image). Many of the finger-like deposits have small channels indicating that a liquid--most likely water--flowed in these areas. Hundreds of individual water and debris flow events might have occurred to create the scene shown here. Each outburst of water from higher upon the crater slopes would have constituted a competition between evaporation, freezing, and gravity.

    The individual deposits at the ends of channels in this MOC image mosaic were used to get a rough estimate of the minimum amount of water that might be involved in each flow event. This is done first by assuming that the deposits are like debris flows on Earth. In a debris flow, no less than about 10% (and no more than 30%) of their volume is water. Second, the volume of an apron deposit is estimated by measuring the area covered in the MOC image and multiplying it by a conservative estimate of thickness, 2 meters (6.5 feet). For a flow containing only 10% water, these estimates conservatively suggest that about 2.5 million liters (660,000 gallons) of water are involved in each event; this is enough to fill about 7 community-sized swimming pools or

  10. Evidence for Recent Liquid Water on Mars: Channeled Aprons in a Small Crater within Newton Crater

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    Newton Crater is a large basin formed by an asteroid impact that probably occurred more than 3 billion years ago. It is approximately 287 kilometers (178 miles) across. The picture shown here (top) highlights the north wall of a specific, smaller crater located in the southwestern quarter of Newton Crater (above). The crater of interest was also formed by an impact; it is about 7 km (4.4 mi) across, which is about 7 times bigger than the famous Meteor Crater in northern Arizona in North America.

    The north wall of the small crater has many narrow gullies eroded into it. These are hypothesized to have been formed by flowing water and debris flows. Debris transported with the water created lobed and finger-like deposits at the base of the crater wall where it intersects the floor (bottom center top image). Many of the finger-like deposits have small channels indicating that a liquid--most likely water--flowed in these areas. Hundreds of individual water and debris flow events might have occurred to create the scene shown here. Each outburst of water from higher upon the crater slopes would have constituted a competition between evaporation, freezing, and gravity.

    The individual deposits at the ends of channels in this MOC image mosaic were used to get a rough estimate of the minimum amount of water that might be involved in each flow event. This is done first by assuming that the deposits are like debris flows on Earth. In a debris flow, no less than about 10% (and no more than 30%) of their volume is water. Second, the volume of an apron deposit is estimated by measuring the area covered in the MOC image and multiplying it by a conservative estimate of thickness, 2 meters (6.5 feet). For a flow containing only 10% water, these estimates conservatively suggest that about 2.5 million liters (660,000 gallons) of water are involved in each event; this is enough to fill about 7 community-sized swimming pools or

  11. The Meteor Meter.

    ERIC Educational Resources Information Center

    Eggensperger, Martin B.

    2000-01-01

    Introduces the Meteor Scatter Project (MSP) in which high school students build an automated meteor observatory and learn to monitor meteor activity. Involves students in activities such as radio frequency survey, antenna design, antenna construction, manual meteor counts, and computer board configuration and installation. (YDS)

  12. The Meteor Meter.

    ERIC Educational Resources Information Center

    Eggensperger, Martin B.

    2000-01-01

    Introduces the Meteor Scatter Project (MSP) in which high school students build an automated meteor observatory and learn to monitor meteor activity. Involves students in activities such as radio frequency survey, antenna design, antenna construction, manual meteor counts, and computer board configuration and installation. (YDS)

  13. Earth atmosphere grazing meteors

    NASA Astrophysics Data System (ADS)

    Kozak, P.

    2017-06-01

    An overview of described in literature earth atmosphere grazing meteors observed with optic methods is proposed. Results of observations of such a meteor detected in Kyiv on 23 September 2003 with super-isocon TV cameras are described. Kinematic parameters of the meteor trajectory in earth atmosphere and its heliocentric orbit elements are given. The comparative analysis of other meteor catalogues for presence in them and a number of such anomalous meteors is carried out.

  14. Gullies in Crater Wall

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-388, 11 June 2003

    Many craters and troughs at polar and middle latitudes on Mars have gullies carved in their walls. These gullies may have formed by running water; others have suggested alternative, exotic fluids such as liquid or gaseous carbon dioxide. This view of martian gullies was acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC). The image shows gullies in the wall of an old meteor impact crater near 39.0oS, 200.7oW. Sunlight illuminates the scene from the upper left.

  15. Gullies in Crater Wall

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-388, 11 June 2003

    Many craters and troughs at polar and middle latitudes on Mars have gullies carved in their walls. These gullies may have formed by running water; others have suggested alternative, exotic fluids such as liquid or gaseous carbon dioxide. This view of martian gullies was acquired by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC). The image shows gullies in the wall of an old meteor impact crater near 39.0oS, 200.7oW. Sunlight illuminates the scene from the upper left.

  16. Crater Copernicus

    NASA Technical Reports Server (NTRS)

    1999-01-01

    HUBBLE SHOOTS THE MOON in a change of venue from peering at the distant universe, NASA's Hubble Space Telescope has taken a look at Earth's closest neighbor in space, the Moon. Hubble was aimed at one of the Moon's most dramatic and photogenic targets, the 58 mile-wide (93 km) impact crater Copernicus. The image was taken while the Space Telescope Imaging Spectrograph(STIS) was aimed at a different part of the moon to measure the colors of sunlight reflected off the Moon. Hubble cannot look at the Sun directly and so must use reflected light to make measurements of the Sun's spectrum. Once calibrated by measuring the Sun's spectrum, the STIS can be used to study how the planets both absorb and reflect sunlight.(upper left)The Moon is so close to Earth that Hubble would need to take a mosaic of 130 pictures to cover the entire disk. This ground-based picture from Lick Observatory shows the area covered in Hubble's photomosaic with the WideField Planetary Camera 2..(center)Hubble's crisp bird's-eye view clearly shows the ray pattern of bright dust ejected out of the crater over one billion years ago, when an asteroid larger than a mile across slammed into the Moon. Hubble can resolve features as small as 600 feet across in the terraced walls of the crater, and the hummock-like blanket of material blasted out by the meteor impact.(lower right)A close-up view of Copernicus' terraced walls. Hubble can resolve features as small as 280 feet across.

  17. Cracked Plain, Buried Craters

    NASA Technical Reports Server (NTRS)

    2004-01-01

    4 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a cracked plain in western Utopia Planitia. The three circular crack patterns indicate the location of three buried meteor impact craters. These landforms are located near 41.9oN, 275.9oW. The image covers an area approximately 3 km (1.9 mi) across. Sunlight illuminates this scene from the lower left.

  18. Gusev Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 25 July 2003

    Wrinkle ridges deform the plains in the bottom of Gusev crater, destination of the MER 'Spirit' rover. The plains were likely created from a flood basalt with ridges forming where there were compressional forces. Dark wind streaks come together to form a dark spot at the bottom of the image where the wind has removed a thin layer of bright dust off a dark surface. On the left side of the image a portion of a lobe of material is visible, which may have resulted from a mud or debris flow. This feature was recently identified by the THEMIS team and may represent the most recent deposit in the crater involving water.

    Image information: VIS instrument. Latitude -13.9, Longitude 175.4 East (184.6 West). 19 meter/pixel resolution.

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

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

  19. Arkhangelsky Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 12 September 2003

    Arkhangelsky crater is just to the northeast of the giant Argyre impact basin in the southern hemisphere of Mars. This THEMIS visible image shows the floor of this crater with a few dark barchan dunes. Dunes form when wind blows sand across a surface. The barchan dunes shown here form when there isn't a whole lot of sand to start with. If there were, other dune forms would be visible.

    Image information: VIS instrument. Latitude -41.2, Longitude 334.9 East (25.1 West). 19 meter/pixel resolution.

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

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

  20. Big Crater as Viewed by Pathfinder Lander - Anaglyph

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The 'Big Crater' is actually a relatively small Martian crater to the southeast of the Mars Pathfinder landing site. It is 1500 meters (4900 feet) in diameter, or about the same size as Meteor Crater in Arizona. Superimposed on the rim of Big Crater (the central part of the rim as seen here) is a smaller crater nicknamed 'Rimshot Crater.' The distance to this smaller crater, and the nearest portion of the rim of Big Crater, is 2200 meters (7200 feet). To the right of Big Crater, south from the spacecraft, almost lost in the atmospheric dust 'haze,' is the large streamlined mountain nicknamed 'Far Knob.' This mountain is over 450 meters (1480 feet) tall, and is over 30 kilometers (19 miles) from the spacecraft. Another, smaller and closer knob, nicknamed 'Southeast Knob' can be seen as a triangular peak to the left of the flanks of the Big Crater rim. This knob is 21 kilometers (13 miles) southeast from the spacecraft.

    The larger features visible in this scene - Big Crater, Far Knob, and Southeast Knob - were discovered on the first panoramas taken by the IMP camera on the 4th of July, 1997, and subsequently identified in Viking Orbiter images taken over 20 years ago. The scene includes rocky ridges and swales or 'hummocks' of flood debris that range from a few tens of meters away from the lander to the distance of South Twin Peak. The largest rock in the nearfield, just left of center in the foreground, nicknamed 'Otter', is about 1.5 meters (4.9 feet) long and 10 meters (33 feet) from the spacecraft.

    This view of Big Crater was produced by combining 6 individual 'Superpan' scenes from the left and right eyes of the IMP camera. Each frame consists of 8 individual frames (left eye) and 7 frames (right eye) taken with different color filters that were enlarged by 500% and then co-added using Adobe Photoshop to produce, in effect, a super-resolution panchromatic frame that is sharper than an individual frame would be.

    The anaglyph view of Big Crater was

  1. Big Crater as Viewed by Pathfinder Lander - Anaglyph

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The 'Big Crater' is actually a relatively small Martian crater to the southeast of the Mars Pathfinder landing site. It is 1500 meters (4900 feet) in diameter, or about the same size as Meteor Crater in Arizona. Superimposed on the rim of Big Crater (the central part of the rim as seen here) is a smaller crater nicknamed 'Rimshot Crater.' The distance to this smaller crater, and the nearest portion of the rim of Big Crater, is 2200 meters (7200 feet). To the right of Big Crater, south from the spacecraft, almost lost in the atmospheric dust 'haze,' is the large streamlined mountain nicknamed 'Far Knob.' This mountain is over 450 meters (1480 feet) tall, and is over 30 kilometers (19 miles) from the spacecraft. Another, smaller and closer knob, nicknamed 'Southeast Knob' can be seen as a triangular peak to the left of the flanks of the Big Crater rim. This knob is 21 kilometers (13 miles) southeast from the spacecraft.

    The larger features visible in this scene - Big Crater, Far Knob, and Southeast Knob - were discovered on the first panoramas taken by the IMP camera on the 4th of July, 1997, and subsequently identified in Viking Orbiter images taken over 20 years ago. The scene includes rocky ridges and swales or 'hummocks' of flood debris that range from a few tens of meters away from the lander to the distance of South Twin Peak. The largest rock in the nearfield, just left of center in the foreground, nicknamed 'Otter', is about 1.5 meters (4.9 feet) long and 10 meters (33 feet) from the spacecraft.

    This view of Big Crater was produced by combining 6 individual 'Superpan' scenes from the left and right eyes of the IMP camera. Each frame consists of 8 individual frames (left eye) and 7 frames (right eye) taken with different color filters that were enlarged by 500% and then co-added using Adobe Photoshop to produce, in effect, a super-resolution panchromatic frame that is sharper than an individual frame would be.

    The anaglyph view of Big Crater was

  2. Henry Crater

    NASA Image and Video Library

    2002-12-19

    Located in Arabia Terra, the crater shown in this image from NASA Mars Odyssey spacecraft is known as Henry Crater. Like many other craters on Mars, the interior of Henry Crater is filled with a layered deposit.

  3. Rampart Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    Rampart crater in Utopia Planitia west of the Viking 2 landing site.

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

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

  4. Impact Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    The irregularly shaped rim of this bowl shaped impact crater is most likely due to erosion and the subsequent infilling of sediment.

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

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

  5. Meteoric aspects of the Earth-grazing asteroid 2004 FH

    NASA Astrophysics Data System (ADS)

    Langbroek, M.

    2004-07-01

    A search for meteors potentially associated with the recent spectacular earthgrazing asteroid 2004 FH in the IAU photographic meteor database yields three meteors from the Harvard project, which is probably not enough to support the notion that 2004 FH is one of the larger meteoroids in a stream. The theoretical radiant is located at alpha = 226 g, delta = -4 g (for March 19), and meteors would have v_infty of about 13.2 km/s, which is very slow. Asteroid 2004 FH would only be dangerous if it is an M-class asteroid. A stony asteroid of this size and speed would disintegrate almost completely in the atmosphere without doing much harm. An M-class (iron) asteroid, however, would shower down fragments weighing many tons, creating a crater field with craters up to 100+ meters wide, and serious blast damage within a few kilometers.

  6. Chemical, isotopic, and gas compositions of selected thermal springs in Arizona, New Mexico, and Utah

    USGS Publications Warehouse

    Mariner, R.H.; Presser, T.S.; Evans, William C.

    1977-01-01

    Twenty-seven thermal springs in Arizona, New Mexico, and Utah were sampled for detailed chemical and isotopic analysis. The springs issue sodium chloride, sodium bicarbonate, or sodium mixed-anion waters of near neutral (6.2) to alkaline (9.2) pH. High concentrations of fluoride, more than 8 milligrams per liter, occur in Arizona in waters from Gillard Hot Springs, Castle Hot Springs, and the unnamed spring of Eagle Creek, and in New Mexico from springs along the Gila River. Deuterium compositions of the thermal waters cover the same range as those expected for meteoric waters in the respective areas. The chemical compositions of the thermal waters indicate that Thermo Hot Springs in Utah and Gillard Hot Springs in Arizona represent hydrothermal systems which are at temperatures higher than 125 deg C. Estimates of subsurface temperature based on the quartz and Na-K-Ca geothermometer differ by up to 60 deg C for Monroe, Joseph, Red Hill, and Crater hot springs in Utah. Similar conflicting estimates of aquifer temperature occur for Verde Hot Springs, the springs near Clifton and Coolidge Dam, in Arizona; and the warm springs near San Ysidro, Radium Hot Springs, and San Francisco Hot Springs, in New Mexico. Such disparities could result from mixing, precipitation of calcium carbonate, or perhaps appreciable concentrations of magnesium. (Woodard-USGS)

  7. Quadrantid Meteor, 2013

    NASA Image and Video Library

    An allsky camera in New Mexico captured a brief video of this Quadrantid fireball meteor on Jan. 3, 2013 at 2:04 a.m. EST. The Quadrantid meteor shower occurs each January and derives its name from...

  8. Meteor Databases in Astronomy

    NASA Astrophysics Data System (ADS)

    Kolomiyets, Svitlana V.

    2017-06-01

    There are specific problems of databases in meteor science such as making meteor databases into the modern research tools. Special institutes and virtual observatories exist for the meteor data storage where the data is online and in open access. However, there are also numerous databases without the open access, such as for example, three radar databases: Kharkiv database with 250,000 meteor orbits in Ukraine, New Zealand database with 500,000 meteor orbits, and Canadian database with more than 3 million meteor orbits. One of the reasons the open access is absent for these databases could be the complexity in the copyright compliance. In the framework of the creation of the modern effective research tool in the meteor science, we discuss here the case of the Kharkiv meteor database.

  9. Catalogue of representative meteor spectra

    NASA Astrophysics Data System (ADS)

    Vojáček, V.; Borovička, J.; Koten, P.; Spurný, P.; Štork, R.

    2016-01-01

    We present a library of low-resolution meteor spectra that includes sporadic meteors, members of minor meteor showers, and major meteor showers. These meteors are in the magnitude range from +2 to -3, corresponding to meteoroid sizes from 1 mm to10 mm. This catalogue is available online at the CDS for those interested in video meteor spectra.

  10. Radio Observations of Meteors.

    PubMed

    Millman, P M

    1954-08-27

    To summarize, we find that the radio technique of meteor observation enables us to extend the systematic recording of meteor rates down to the 9th or 10th magnitude; to determine satisfactory heights and velocities on a scale previously impossible; to calculate the orbits of meteor showers and individual meteors, in particular those that appear only in the daytime; and to study wind drift and fine structure in the ionosphere. The radio observations have quite definitely indicated that down to the 9th magnitude, corresponding to particles approximately 1 mm in diameter, meteors are members of the solar system and do not come from interstellar space.

  11. Impact cratering calculations

    NASA Technical Reports Server (NTRS)

    Ahrens, Thomas J.; Okeefe, J. D.; Smither, C.; Takata, T.

    1991-01-01

    In the course of carrying out finite difference calculations, it was discovered that for large craters, a previously unrecognized type of crater (diameter) growth occurred which was called lip wave propagation. This type of growth is illustrated for an impact of a 1000 km (2a) silicate bolide at 12 km/sec (U) onto a silicate half-space at earth gravity (1 g). The von Misses crustal strength is 2.4 kbar. The motion at the crater lip associated with this wave type phenomena is up, outward, and then down, similar to the particle motion of a surface wave. It is shown that the crater diameter has grown d/a of approximately 25 to d/a of approximately 4 via lip propagation from Ut/a = 5.56 to 17.0 during the time when rebound occurs. A new code is being used to study partitioning of energy and momentum and cratering efficiency with self gravity for finite-sized objects rather than the previously discussed planetary half-space problems. These are important and fundamental subjects which can be addressed with smoothed particle hydrodynamic (SPH) codes. The SPH method was used to model various problems in astrophysics and planetary physics. The initial work demonstrates that the energy budget for normal and oblique impacts are distinctly different than earlier calculations for silicate projectile impact on a silicate half space. Motivated by the first striking radar images of Venus obtained by Magellan, the effect of the atmosphere on impact cratering was studied. In order the further quantify the processes of meteor break-up and trajectory scattering upon break-up, the reentry physics of meteors striking Venus' atmosphere versus that of the Earth were studied.

  12. Large meteor bodies

    NASA Astrophysics Data System (ADS)

    Terentjeva, A. K.

    A population of 69 large meteor bodies with extra-atmospheric masses from several kilograms up to several tens of tons detected from photographic observations of bright fireballs of Prairie and European networks is investigated. A half of these objects are "meteorite producers". A relationship between large meteor bodies and meteor streams is analysed. A unique group of meteorite producers moving along extremely short period orbits is considered. Orbits of these bodies are entirely located inside the Earth's orbit similarly to the orbits of system of the Eccentrid meteor bodies, has been discovered by the author in 1981. Interrelationship between all of these bodies and meteor streams is investigated. Some associations have been revealed. Families may exist inside the complex of minor bodies which consist of meteor streams, asteroids of Aten, Apollo and Amor type and large meteor bodies, including meteorite producers.

  13. Crater on Crater

    NASA Image and Video Library

    2016-12-07

    This VIS images shows part of two unnamed craters in Noachis Terra. The younger of the two craters is at the bottom of the image with one side visible in the image. The older and much larger crater has just part of the rim and floor visible towards the top of the image. The overlapping of one crater on top of another allows for relative dating to be done. We don't know the exact ages of each crater, but we can define which came first. Orbit Number: 65804 Latitude: -49.4751 Longitude: 14.2708 Instrument: VIS Captured: 2016-10-14 03:52 http://photojournal.jpl.nasa.gov/catalog/PIA21184

  14. Huygens Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 15 July 2003

    The floor of the 450 km diameter crater named after Dutch astronomer Christian Huygens (1629-1695) shows an unusual texture. Smooth-topped mesas are scattered across a more rugged surface. The mesas are testament to a former smooth layer of material that is in the process of eroding away.

    Image information: VIS instrument. Latitude -16.2, Longitude 54.5 East (305.5 West). 19 meter/pixel resolution.

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

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

  15. Practical Meteor Stream Forecasting

    NASA Technical Reports Server (NTRS)

    Cooke, William J.; Suggs, Robert M.

    2003-01-01

    Inspired by the recent Leonid meteor storms, researchers have made great strides in our ability to predict enhanced meteor activity. However, the necessary calibration of the meteor stream models with Earth-based ZHRs (Zenith Hourly Rates) has placed emphasis on the terran observer and meteor activity predictions are published in such a manner to reflect this emphasis. As a consequence, many predictions are often unusable by the satellite community, which has the most at stake and the greatest interest in meteor forecasting. This paper suggests that stream modelers need to pay more attention to the needs of this community and publish not just durations and times of maxima for Earth, but everything needed to characterize the meteor stream in and out of the plane of the ecliptic, which, at a minimum, consists of the location of maximum stream density (ZHR) and the functional form of the density decay with distance from this point. It is also suggested that some of the terminology associated with meteor showers may need to be more strictly defined in order to eliminate the perception of crying wolf by meteor scientists. An outburst is especially problematic, as it usually denotes an enhancement by a factor of 2 or more to researchers, but conveys the notion of a sky filled with meteors to satellite operators and the public. Experience has also taught that predicted ZHRs often lead to public disappointment, as these values vastly overestimate what is seen.

  16. Rare Double Quadrantid Meteor Sighting

    NASA Image and Video Library

    The wide-field meteor camera at NASA's Marshall Space Flight Center recorded these two simultaneous Quadrantid meteors on Jan. 4 at approximately 5 a.m. EST. Moving at 92,000 mph, the meteors flash...

  17. Craters Modified by Ice

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 2 October 2003

    These craters, located in the southern highland heavily cratered terrain, show heavy degradation, most likely caused by the presence of water ice. A smaller crater is located in the floor of a larger crater, showing lobate ejecta thought to be created by water melted by the force of the impacting body. Gullies on the northern rim of the smaller crater may indicate accumulations of snow and subsequent melting. In the larger crater, the northern rim is greatly softened, with sinuous features suggestive of downslope flow, also potentially caused by creep of ground ice.

    Image information: VIS instrument. Latitude -40.4, Longitude 132.5 East (227.5 West). 38 meter/pixel resolution.

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

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

  18. Secondary Craters

    NASA Image and Video Library

    2016-12-21

    This image of a southern mid-latitude crater was intended to investigate the lineated material on the crater floor. At the higher resolution of HiRISE, the image reveals a landscape peppered by small impact craters. These craters range from about 30 meters in diameter down to the resolution limit (about 2 meter diameter in this image acquired by averaging 2x2 picture elements). Such dense clusters of small craters are frequently formed by secondary craters, caused by the impact of material that was excavated and ejected from the surface of Mars during the creation of a larger nearby crater by the impact of a comet or an asteroid. Secondary impact craters are both interesting and vexing. They are interesting because they show the trajectories of the material that was ejected from the primary impact with the greatest speeds, typically material from near the surface of the blast zone. Secondary craters are often found along the traces of crater rays, linear features that extend radially from fresh impact craters and can reach many crater diameters in length. Secondary craters can be useful when crater rays are visible and the small craters can be associated with a particular primary impact crater. They can be used to constrain the age of the surface where they fell, since the surface must be older than the impact event. The age of the crater can be approximately estimated from the probability of an impact that produced a crater of such a size within a given area of Mars over a given time period. But these secondary craters can also be perplexing when no crater rays are preserved and a source crater is not easily identifiable, as is the case here. The impact that formed these secondary craters took place long enough ago that their association with a particular crater has been erased. They do not appear along the trace of a crater ray that is still apparent in visible or thermal infrared observations. These secondary craters complicate the task of estimating the age of

  19. Pair of Craters

    NASA Technical Reports Server (NTRS)

    2005-01-01

    14 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a 1.5 meters per pixel (5 ft/pixel) view of a pair of small meteor impact craters in the Arena Colles region of Mars, located north of Isidis Planitia.

    Location near: 22.7oN, 278.5oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  20. Dynamic Tensile Strength of Crustal Rocks and Application to Impact Cratering

    NASA Astrophysics Data System (ADS)

    Ai, H.; Ahrens, T. J.

    2003-01-01

    Dynamic tensile strengths of two crustal rocks, San Marcos gabbro and Coconino sandstone (Meteor Crater, Arizona), were determined by carrying out flat plate impact experiments. Porosity of San Marcos gabbro is very low, and the reported porosity for Coconino sandstone is approx. 25%. Aluminum flyer plates were used for gabbro with impact velocities of 13 to 50 m/s, which produce tensile stresses in the range of 120 to 450 MPa. PMMA flyer plates were used for sandstone with impact velocities of 5 to 25 m/s, resulting tensile stresses in the range of approx. 13 to 55 MPa. Impact was normal to the bedding of sandstone. Tensile duration times for two cases were approx. 1 and approx. 2.3 microns, respectively. Pre-shot and post-shot ultrasonic P and S wave velocities were measured for the targets. Velocity reduction for gabbro occurred at approx. 150 MPa, very close to the earlier result determined by microscopic examination. The reduction of S wave is slightly higher than that of P wave. This indicates that the impact-induced cracks were either aligned, or there were residual fluids within cracks, or both. Data for sandstone velocity reduction was few and scattered caused by its high porosity. The range of dynamic tensile strength of Coconino sandstone is within 25 and 30 MPa. Obvious radial cracks at certain stresses indicate that deformation was not restricted to one dimensional strain as being assumed. Spall fragmentation occurred above 40 MPa. The combination of impact velocities, U (km/s), and impactor radii, a0)(m, are constrained by Meteor Crater fracture depth, approx. 850 m, and the dynamic tensile fracture strength from our experiments, 40 MPa. Volume of the crater for each impact was calculated using V = 0.009mU1.65, where V is crater volume (cu m), m is the mass of the impactor (kg). Volume of impact with U = 28 km/s, a0 = 10 m is close to the real Meteor Crater volume, 7.6e7 cu m. Impact energy for this case is 3.08 Mt., which agrees well with theoretical

  1. Arizona Wildfire

    Atmospheric Science Data Center

    2013-04-23

    article title:  Wildfire in Arizona     View larger image ... plume on June 3, 2011 from the wildfires currently raging in Arizona. It is overlaid on an image captured by the Moderate Resolution Imaging ...

  2. Meteor Beliefs Project: Introduction

    NASA Astrophysics Data System (ADS)

    McBeath, A.; Gheorghe, A. D.

    2003-05-01

    A new project to investigate beliefs in meteors and meteoric phenomena in past and present times using chiefly folklore, mythology, prose and poetic literature, is described. Some initial examples are given, along with a bibliography of relevant items already in print in IMO publications.

  3. Northern Plains 'Crater'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    10 December 2004 The lower left (southwest) corner of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the location of a somewhat filled and buried meteor impact crater on the northern plains of Mars. The dark dots are boulders. A portion of a similar feature is seen in the upper right (northeast) corner of the image. This picture, showing landforms (including the odd mound north/northeast of the crater) that are typical of the martian northern lowland plains, was obtained as part of the MGS MOC effort to support the search for a landing site for the Phoenix Mars Scout lander. Phoenix will launch in 2007 and land on the northern plains in 2008. This image is located near 68.0oN, 227.4oW, and covers an area approximately 3 km (1.9 mi) wide. The scene is illuminated by sunlight from the lower left.

  4. Gullies in Terraced Crater Wall

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-375, 29 May 2003

    Gullies--possibly formed by a liquid such as water in the recent martian past--formed at two different levels in the walls of a meteor impact crater near 36.2oS, 185.5oW. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies in the upper crater wall (top of the image) and emergent from the slope of a lower terrace (bottom of the image). Sunlight illuminates the scene from the upper left.

  5. Gullies in Terraced Crater Wall

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-375, 29 May 2003

    Gullies--possibly formed by a liquid such as water in the recent martian past--formed at two different levels in the walls of a meteor impact crater near 36.2oS, 185.5oW. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies in the upper crater wall (top of the image) and emergent from the slope of a lower terrace (bottom of the image). Sunlight illuminates the scene from the upper left.

  6. Iturralde Crater, Bolivia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    NASA scientists will venture into an isolated part of the Bolivian Amazon to try and uncover the origin of a 5 mile (8 kilometer) diameter crater there known as the Iturralde Crater. Traveling to this inhospitable forest setting, the Iturralde Crater Expedition 2002 will seek to determine if the unusual circular crater was created by a meteor or comet. Organized by Dr. Peter Wasilewski of NASA's Goddard Space Flight Center, Greenbelt, Md., the Iturralde Crater Expedition 2002 will be led by Dr. Tim Killeen of Conservation International, which is based in Bolivia. Killeen will be assisted by Dr. Compton Tucker of Goddard. The team intends to collect and analyze rocks and soil, look for glass particles that develop from meteor impacts and study magnetic properties in the area to determine if the Iturralde site was indeed created by a meteor.

    This image was acquired on June 29, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation

  7. Iturralde Crater, Bolivia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    NASA scientists will venture into an isolated part of the Bolivian Amazon to try and uncover the origin of a 5 mile (8 kilometer) diameter crater there known as the Iturralde Crater. Traveling to this inhospitable forest setting, the Iturralde Crater Expedition 2002 will seek to determine if the unusual circular crater was created by a meteor or comet. Organized by Dr. Peter Wasilewski of NASA's Goddard Space Flight Center, Greenbelt, Md., the Iturralde Crater Expedition 2002 will be led by Dr. Tim Killeen of Conservation International, which is based in Bolivia. Killeen will be assisted by Dr. Compton Tucker of Goddard. The team intends to collect and analyze rocks and soil, look for glass particles that develop from meteor impacts and study magnetic properties in the area to determine if the Iturralde site was indeed created by a meteor.

    This image was acquired on June 29, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation

  8. Meteor Researches at Khnure

    NASA Astrophysics Data System (ADS)

    Kolomiyets, Svitlana V.; Voloshchuk, Yuri I.; Kashcheyev, Boris L.; Slipchenko, Nikolay I.

    The Scientific Educational Center of Radioengineering of the Kharkiv National University of Radioelectronics (KHNURE: ) is one of the oldest radar meteor centers which was founded by B. L. Kashcheyev in 1958. The first automatic meteor radar system in Ukraine “MARS” is connected with our University. There are long-term observational series of meteor rates and orbital data in the Center. Fields of the KHNURE researches are: a structure of meteor showers a determination of meteoroid orbits an influx of cosmic rubbish in the Earth atmosphere search of parental bodies of meteoroids a statistic analysis of measurement results of radiometeors an estimation of errors of meteor radar measurements a search for real hyperbolic orbits and interstellar meteoroids. KHNURE disposes a unique electronic orbital catalogue. This catalogue contains the primary information velocities radiants and orbits of nearly 250000 radiometeoroids with masses from 0.001 to 0.000001 g. The “MARS” registered these data during observations of 1972 1978. From these data 5160 meteor streams are singled out. New classification of streams is made in view of their structure. The study of meteor stream orbits from the KHNURE data bank allow to predict orbits of a big number of undiscovered “dangerous” NEOs

  9. Meteor researches at KHNURE

    NASA Astrophysics Data System (ADS)

    Kolomiyets, Svitlana V.; Voloshchuk, Yuri I.; Kashcheyev, Boris L.; Slipchenko, Nikolay I.

    2005-01-01

    The Scientific Educational Center of Radioengineering of the Kharkiv National University of Radioelectronics (KHNURE: ) is one of the oldest radar meteor centers which was founded by B. L. Kashcheyev in 1958. The first automatic meteor radar system in Ukraine “MARS” is connected with our University. There are long-term observational series of meteor rates and orbital data in the Center. Fields of the KHNURE researches are: a structure of meteor showers a determination of meteoroid orbits an influx of cosmic rubbish in the Earth atmosphere search of parental bodies of meteoroids a statistic analysis of measurement results of radiometeors an estimation of errors of meteor radar measurements a search for real hyperbolic orbits and interstellar meteoroids. KHNURE disposes a unique electronic orbital catalogue. This catalogue contains the primary information velocities radiants and orbits of nearly 250000 radiometeoroids with masses from 0.001 to 0.000001 g. The “MARS” registered these data during observations of 1972 1978. From these data 5160 meteor streams are singled out. New classification of streams is made in view of their structure. The study of meteor stream orbits from the KHNURE data bank allow to predict orbits of a big number of undiscovered “dangerous” NEOs.

  10. Impact Crater with Peak

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 14 June 2002) The Science This THEMIS visible image shows a classic example of a martian impact crater with a central peak. Central peaks are common in large, fresh craters on both Mars and the Moon. This peak formed during the extremely high-energy impact cratering event. In many martian craters the central peak has been either eroded or buried by later sedimentary processes, so the presence of a peak in this crater indicates that the crater is relatively young and has experienced little degradation. Observations of large craters on the Earth and the Moon, as well as computer modeling of the impact process, show that the central peak contains material brought from deep beneath the surface. The material exposed in these peaks will provide an excellent opportunity to study the composition of the martian interior using THEMIS multi-spectral infrared observations. The ejecta material around the crater can is well preserved, again indicating relatively little modification of this landform since its initial creation. The inner walls of this approximately 18 km diameter crater show complex slumping that likely occurred during the impact event. Since that time there has been some downslope movement of material to form the small chutes and gullies that can be seen on the inner crater wall. Small (50-100 m) mega-ripples composed of mobile material can be seen on the floor of the crater. Much of this material may have come from the walls of the crater itself, or may have been blown into the crater by the wind. The Story When a meteor smacked into the surface of Mars with extremely high energy, pow! Not only did it punch an 11-mile-wide crater in the smoother terrain, it created a central peak in the middle of the crater. This peak forms kind of on the 'rebound.' You can see this same effect if you drop a single drop of milk into a glass of milk. With craters, in the heat and fury of the impact, some of the land material can even liquefy. Central peaks like the one

  11. Impact Crater with Peak

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 14 June 2002) The Science This THEMIS visible image shows a classic example of a martian impact crater with a central peak. Central peaks are common in large, fresh craters on both Mars and the Moon. This peak formed during the extremely high-energy impact cratering event. In many martian craters the central peak has been either eroded or buried by later sedimentary processes, so the presence of a peak in this crater indicates that the crater is relatively young and has experienced little degradation. Observations of large craters on the Earth and the Moon, as well as computer modeling of the impact process, show that the central peak contains material brought from deep beneath the surface. The material exposed in these peaks will provide an excellent opportunity to study the composition of the martian interior using THEMIS multi-spectral infrared observations. The ejecta material around the crater can is well preserved, again indicating relatively little modification of this landform since its initial creation. The inner walls of this approximately 18 km diameter crater show complex slumping that likely occurred during the impact event. Since that time there has been some downslope movement of material to form the small chutes and gullies that can be seen on the inner crater wall. Small (50-100 m) mega-ripples composed of mobile material can be seen on the floor of the crater. Much of this material may have come from the walls of the crater itself, or may have been blown into the crater by the wind. The Story When a meteor smacked into the surface of Mars with extremely high energy, pow! Not only did it punch an 11-mile-wide crater in the smoother terrain, it created a central peak in the middle of the crater. This peak forms kind of on the 'rebound.' You can see this same effect if you drop a single drop of milk into a glass of milk. With craters, in the heat and fury of the impact, some of the land material can even liquefy. Central peaks like the one

  12. Minor meteor shower activity

    NASA Astrophysics Data System (ADS)

    Rendtel, J.

    2016-01-01

    Video meteor observations provide us with data to analyze structures in minor meteor showers or weak features in flux profiles. Samples obtained independently by other techniques allow to calibrate the data sets and to improve the confidence of results as demonstrated with a few results. Both, the confirmation of events predicted by model calculation and the input of observational data to improve the modelling results may help to better understand meteoroid stream evolution processes. Furthermore, calibrated data series can be used for studies of the long-term evolution of meteor shower activity.

  13. Crater Wall and Floor

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    3D Projection onto MOLA data [figure removed for brevity, see original site]

    The impact crater observed in this THEMIS image taken in Terra Cimmeria suggests sediments have filled the crater due to the flat and smooth nature of the floor compared to rougher surfaces at higher elevations. The abundance of several smaller impact craters on the floor of the larger crater indicate however that the flat surface has been exposed for an extended period of time. The smooth surface of the crater floor and rougher surfaces at higher elevations are observed in the 3-D THEMIS image that is draped over MOLA topography (2X vertical exaggeration).

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

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

    Image information: VIS instrument. Latitude -22.9, Longitude 155.7 East (204.3 West). 19 meter/pixel resolution.

  14. Mare Chromium Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    This crater, located in Mare Chromium, shows evidence of exterior modification, with little interior modification. While the rim is still visible, the ejecta blanket has been removed or covered. There is some material at the bottom of the crater, but the interior retains the bowl shape from the initial formation of the crater.

    Image information: VIS instrument. Latitude -34.4, Longitude 174.4 East (185.6 West). 19 meter/pixel resolution.

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

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

  15. Mare Chromium Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    This crater, located in Mare Chromium, shows evidence of exterior modification, with little interior modification. While the rim is still visible, the ejecta blanket has been removed or covered. There is some material at the bottom of the crater, but the interior retains the bowl shape from the initial formation of the crater.

    Image information: VIS instrument. Latitude -34.4, Longitude 174.4 East (185.6 West). 19 meter/pixel resolution.

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

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

  16. Terra Cimmeria Crater Landslide

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

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

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

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

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

  17. Isidis Crater Landslide

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The landslide in this VIS image is located inside an impact crater located south of the Isidis Planitia region of Mars. As with the previous unnamed crater landslide, this one formed due to slope failure of the inner crater rim.

    Image information: VIS instrument. Latitude -2.9, Longitude 90.8 East (269.2 West). 19 meter/pixel resolution.

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

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

  18. Terra Cimmeria Crater Landslide

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

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

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

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

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

  19. Isidis Crater Landslide

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The landslide in this VIS image is located inside an impact crater located south of the Isidis Planitia region of Mars. As with the previous unnamed crater landslide, this one formed due to slope failure of the inner crater rim.

    Image information: VIS instrument. Latitude -2.9, Longitude 90.8 East (269.2 West). 19 meter/pixel resolution.

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

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

  20. Current trends in meteor spectroscopy

    NASA Technical Reports Server (NTRS)

    Millman, P. M.

    1982-01-01

    The history of progress over more than a century in meteor spectroscopy is summarized. The observational data were originally visual records, but in the beginning of the 20th century photography of meteor spectra was undertaken. In the forties, 60 meteor spectra were photographed. Interest in the upper atmosphere led to the development of more efficient meteor cameras which employ replica gratings, and electronic image intensification systems recordings on video tape which resulted in the availability of several thousand meteor spectra.

  1. Young Crater

    NASA Image and Video Library

    2017-01-31

    This image captured by NASA 2001 Mars Odyssey spacecraft shows two craters in Terra Cimmeria just north of Kepler Crater. The small crater in the middle of the image is a relatively new crater. The interior rim has gullies, but the bowl shape shows that there has been very little deposition of materials. Additionally, the radial emplacement of thin ejecta is still identifiable, and can be seen in the larger crater in the top of the image. With time the crater floor will flatten due to influx of materials and the subtle radial ejecta will be hidden by dust. While the actual age of the small crater is not known, it is relatively younger than the larger crater. Orbit Number: 66523 Latitude: -44.3019 Longitude: 139.301 Instrument: VIS Captured: 2016-12-12 09:31 http://photojournal.jpl.nasa.gov/catalog/PIA21300

  2. Crater Ejecta

    NASA Image and Video Library

    2012-08-02

    The craters in this image from NASA 2001 Mars Odyssey spacecraft are located in a region of prolonged wind action. The ejecta of the craters is more resistant to the wind than the materials around it.

  3. Canuleia Crater

    NASA Image and Video Library

    2012-04-24

    This image from NASA Dawn spacecraft of asteroid Vesta shows Canuleia crater, a large, irregularly shaped crater. Other interesting features of Canuleia include the diffuse bright material that is both inside and outside of its rim.

  4. Freedom Crater

    NASA Image and Video Library

    2003-02-20

    Freedom crater, located in Acidalia Planitia, exhibits a concentric ring pattern in its interior as seen in this image from NASA Mars Odyssey spacecraft, suggesting that there has been some movement of these materials towards the center of the crater.

  5. Flooded Crater

    NASA Image and Video Library

    2003-04-04

    This image from NASA Mars Odyssey spacecraft shows a flooded crater in Amazonis Planitia. This crater has been either flooded with mud and or lava. The fluid then ponded up, dried and formed the surface textures we see today.

  6. Impact Crater

    NASA Image and Video Library

    2003-01-15

    The relatively flat floor and terrace walls of this impact crater imaged by NASA Mars Odyssey spacecraft suggest the crater was partly infilled with sediment and subsequently eroded to its present day form.

  7. Impact Craters

    NASA Image and Video Library

    2003-03-22

    The fluidized impact crater ejecta and flat crater floors observed in this image from NASA Mars Odyssey spacecraft suggest near-surface volatiles once played an important role in modifying the Martian surface.

  8. Crater Ejecta

    NASA Image and Video Library

    2012-06-05

    This image from NASA 2001 Mars Odyssey spacecraft contains a relatively young crater and its ejecta. Layering in the ejecta is visible and relates to the shock waves from the impact. This unnamed crater is located in Arabia Terra.

  9. Lismore Crater

    NASA Image and Video Library

    2012-07-17

    This image from NASA 2001 Mars Odyssey spacecraft is of Lismore Crater. This crater, located in Chryse Planitia, is relatively unmodified, meaning it appears very much like it did when it first formed.

  10. Crater Features

    NASA Image and Video Library

    2015-07-06

    Today's VIS image is of an unnamed crater located on the floor of the much larger Newton Crater. This crater had a central peak, gullies on the inner rim and dunes on the northern part of the crater floor. Orbit Number: 59391 Latitude: -41.9785 Longitude: 201.934 Instrument: VIS Captured: 2015-05-04 23:15 http://photojournal.jpl.nasa.gov/catalog/PIA19504

  11. Double Crater

    NASA Image and Video Library

    2012-03-23

    A double crater, called a crater doublet, is seen in the bottom right part of this image from NASA Dawn spacecraft of asteroid Vesta. This crater doublet was likely formed by the simultaneous impact of two fragments of a split projectile.

  12. Cratering mechanics

    NASA Technical Reports Server (NTRS)

    Ivanov, B. A.

    1986-01-01

    Main concepts and theoretical models which are used for studying the mechanics of cratering are discussed. Numerical two-dimensional calculations are made of explosions near a surface and high-speed impact. Models are given for the motion of a medium during cratering. Data from laboratory modeling are given. The effect of gravitational force and scales of cratering phenomena is analyzed.

  13. Cydonia Craters

    NASA Image and Video Library

    2003-03-22

    In this image from NASA Mars Odyssey, eroded mesas and secondary craters dot the landscape in an area of Cydonia Mensae. The single oval-shaped crater displays a butterfly ejecta pattern, indicating that the crater formed from a low-angle impact.

  14. Layered Rocks in Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    19 June 2004 Exposures of layered, sedimentary rock are common on Mars. From the rock outcrops examined by the Mars Exploration Rover, Opportunity, in Meridiani Planum to the sequence in Gale Crater's central mound that is twice the thickness of of the sedimentary rocks exposed by Arizona's Grand Canyon, Mars presents a world of sediment to study. This unusual example, imaged by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), shows eroded layer outcrops in a crater in Terra Tyrrhena near 15.4oS, 270.5oW. Sedimentary rocks provide a record of past climates and events. Perhaps someday the story told by the rocks in this image will be known via careful field work. The image covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from the left.

  15. Trouvelot Crater Deposit

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    Like many of the craters in the Oxia Palus region of Mars, Trouvelot Crater hosts an eroded, light-toned, sedimentary deposit on its floor. Compared with the much larger example in Becquerel Crater to the NE, the Trouvelot deposit has been so eroded by the scouring action of dark, wind-blown sand that very little of it remains. Tiny outliers of bright material separated from the main mass attest to the once, more really extensive coverage by the deposit. A similar observation can be made for White Rock, the best known example of a bright, crater interior deposit. The origin of the sediments in these deposits remains enigmatic but they are likely the result of fallout from ash or dust carried by the thin martian atmosphere.

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

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

  16. Read Arizona.

    ERIC Educational Resources Information Center

    Arizona State Dept. of Library, Archives and Public Records, Phoenix.

    This manual, designed to help public libraries in Arizona to plan their summer reading programs for children, celebrates the 25th anniversary of the Arizona Reading Program. The material in the manual is prepared for libraries to adapt for their own uses. Chapters of the manual include: (1) Introductory Materials; (2) Goals, Objectives and…

  17. Read Arizona.

    ERIC Educational Resources Information Center

    Arizona State Dept. of Library, Archives and Public Records, Phoenix.

    This manual, designed to help public libraries in Arizona to plan their summer reading programs for children, celebrates the 25th anniversary of the Arizona Reading Program. The material in the manual is prepared for libraries to adapt for their own uses. Chapters of the manual include: (1) Introductory Materials; (2) Goals, Objectives and…

  18. Meteor Beliefs Project: meteors in the poems of John Donne

    NASA Astrophysics Data System (ADS)

    McBeath, A.; Gheorghe, A. D.

    2004-07-01

    An examination of the uses of meteor imagery in the poems of Englishman John Donne (1572-1631) is made, revealing a set of beliefs reflecting the period when ideas about astronomy, including meteors, were beginning to undergo radical change.

  19. Photoacoustic Sounds from Meteors

    NASA Astrophysics Data System (ADS)

    Spalding, Richard; Tencer, John; Sweatt, William; Conley, Benjamin; Hogan, Roy; Boslough, Mark; Gonzales, Gigi; Spurný, Pavel

    2017-02-01

    Concurrent sound associated with very bright meteors manifests as popping, hissing, and faint rustling sounds occurring simultaneously with the arrival of light from meteors. Numerous instances have been documented with -11 to -13 brightness. These sounds cannot be attributed to direct acoustic propagation from the upper atmosphere for which travel time would be several minutes. Concurrent sounds must be associated with some form of electromagnetic energy generated by the meteor, propagated to the vicinity of the observer, and transduced into acoustic waves. Previously, energy propagated from meteors was assumed to be RF emissions. This has not been well validated experimentally. Herein we describe experimental results and numerical models in support of photoacoustic coupling as the mechanism. Recent photometric measurements of fireballs reveal strong millisecond flares and significant brightness oscillations at frequencies ≥40 Hz. Strongly modulated light at these frequencies with sufficient intensity can create concurrent sounds through radiative heating of common dielectric materials like hair, clothing, and leaves. This heating produces small pressure oscillations in the air contacting the absorbers. Calculations show that -12 brightness meteors can generate audible sound at ~25 dB SPL. The photoacoustic hypothesis provides an alternative explanation for this longstanding mystery about generation of concurrent sounds by fireballs.

  20. Photoacoustic Sounds from Meteors

    PubMed Central

    Spalding, Richard; Tencer, John; Sweatt, William; Conley, Benjamin; Hogan, Roy; Boslough, Mark; Gonzales, GiGi; Spurný, Pavel

    2017-01-01

    Concurrent sound associated with very bright meteors manifests as popping, hissing, and faint rustling sounds occurring simultaneously with the arrival of light from meteors. Numerous instances have been documented with −11 to −13 brightness. These sounds cannot be attributed to direct acoustic propagation from the upper atmosphere for which travel time would be several minutes. Concurrent sounds must be associated with some form of electromagnetic energy generated by the meteor, propagated to the vicinity of the observer, and transduced into acoustic waves. Previously, energy propagated from meteors was assumed to be RF emissions. This has not been well validated experimentally. Herein we describe experimental results and numerical models in support of photoacoustic coupling as the mechanism. Recent photometric measurements of fireballs reveal strong millisecond flares and significant brightness oscillations at frequencies ≥40 Hz. Strongly modulated light at these frequencies with sufficient intensity can create concurrent sounds through radiative heating of common dielectric materials like hair, clothing, and leaves. This heating produces small pressure oscillations in the air contacting the absorbers. Calculations show that −12 brightness meteors can generate audible sound at ~25 dB SPL. The photoacoustic hypothesis provides an alternative explanation for this longstanding mystery about generation of concurrent sounds by fireballs. PMID:28145486

  1. Photoacoustic sounds from meteors

    DOE PAGES

    Spalding, Richard; Tencer, John; Sweatt, William; ...

    2017-02-01

    Concurrent sound associated with very bright meteors manifests as popping, hissing, and faint rustling sounds occurring simultaneously with the arrival of light from meteors. Numerous instances have been documented with –11 to –13 brightness. These sounds cannot be attributed to direct acoustic propagation from the upper atmosphere for which travel time would be several minutes. Concurrent sounds must be associated with some form of electromagnetic energy generated by the meteor, propagated to the vicinity of the observer, and transduced into acoustic waves. Previously, energy propagated from meteors was assumed to be RF emissions. This has not been well validated experimentally.more » Herein we describe experimental results and numerical models in support of photoacoustic coupling as the mechanism. Recent photometric measurements of fireballs reveal strong millisecond flares and significant brightness oscillations at frequencies ≥40 Hz. Strongly modulated light at these frequencies with sufficient intensity can create concurrent sounds through radiative heating of common dielectric materials like hair, clothing, and leaves. This heating produces small pressure oscillations in the air contacting the absorbers. Calculations show that –12 brightness meteors can generate audible sound at ~25 dB SPL. As a result, the photoacoustic hypothesis provides an alternative explanation for this longstanding mystery about generation of concurrent sounds by fireballs.« less

  2. An unusual meteor spectrum

    NASA Technical Reports Server (NTRS)

    Cook, A. F.; Hemenway, C. L.; Millman, P. M.; Swider, A.

    1973-01-01

    An extraordinary spectrum of a meteor at a velocity of about 18.5 + or - 1.0 km/s was observed with an image orthicon camera. The radiant of the meteor was at an altitude of about 49 deg. It was first seen showing a yellow red continuous spectrum alone at a height of 137 + or - 8 km which is ascribed to the first positive group of nitrogen bands. After the meteor had descended to 116 + or - 6 km above sea level it brightened rapidly from its previous threshold brightness into a uniform continuum, the D-line of neutral sodium appeared, and at height 105 + or - 5 km all the other lines of the spectrum also appeared. The continuum remained dominant to the end. Water of hydration and entrained carbon flakes of characteristic dimension about 0.2 micron or less are proposed as constituents of the meteoroid to explain these phenomena.

  3. Watching meteors on Triton

    NASA Astrophysics Data System (ADS)

    Pesnell, W. Dean; Grebowsky, J. M.; Weisman, Andrew L.

    2004-06-01

    The thin atmosphere of Neptune's moon Triton is dense enough to ablate micrometeoroids as they pass through. A combination of Triton's orbital velocity around Neptune and its orbital velocity around the Sun gives a maximum meteoroid impact velocity of approximately 19 km s -1, sufficient to heat the micrometeoroids to visibility as they enter. The ablation profiles of icy and stony micrometeoroids were calculated, along with the estimated brightness of the meteors. In contrast to the terrestrial case, visible meteors would extend very close to the surface of Triton. In addition, the variation in the meteoroid impact velocity as Triton orbits Neptune produces a large variation in the brightness of meteors with orbital phase, a unique Solar System phenomenon.

  4. METEORIC-HYDROTHERMAL SYSTEMS.

    USGS Publications Warehouse

    Criss, Robert E.; Taylor, Hugh P.

    1986-01-01

    This paper summarizes the salient characteristics of meteoric-hydrothermal systems, emphasing the isotopic systematics. Discussions of permeable-medium fluid dynamics and the geology and geochemistry of modern geothermal systems are also provided, because they are essential to any understanding of hydrothermal circulation. The main focus of the paper is on regions of ancient meteoric-hydrothermal activity, which give us information about the presently inaccessible, deep-level parts of modern geothermal systems. It is shown oxygen and hydrogen isotopes provide a powerful method to discover and map fossil hydrothermal systems and to investigate diverse associated aspects of rock alteration and ore deposition.

  5. Discovery of Leonid Meteoric Cloud

    DTIC Science & Technology

    2007-11-02

    as a local enhancement in sky brightness during the meteor shower in 1998. The radius of the trail, deduced from the spatial extent of the cloud, is...A meteoric cloud is a faint glow of sunlight scattered by the small meteoroids in the trail along a parent comets orbit. Here we report the first...detection of the meteoric cloud associated with the Leonid meteor stream. Our photometric observations, performed on Mauna Kea, Hawaii, reveal the cloud

  6. Using quantitative topographic analysis to understand the role of water on transport and deposition processes on crater walls

    NASA Astrophysics Data System (ADS)

    Palucis, Marisa Christina

    The amount of water runoff need to evolve landscapes is rarely assessed. Empirical studies correlate erosion rate to runoff or mean annual precipitation, but rarely is the full history of a landscape known such that it is possible to assess how much water was required to produce it. While this may not seem to be of primary importance on Earth where water is commonly plentiful, on Mars the amount of water to drive landscape evolution is a key question. Here we tackle this question through a series of five chapters, one devoted to field work at Meteor Crater, another to laboratory experiments about controlling processes, and then two chapters on analysis of landforms and implications of water runoff on Mars (associated with the Mars Science Laboratory mission to Gale Crater), and then we complete this effort with a consideration of how we can reliably assign relative timing between events resulting in small depositional features. What follows below is a summary of what is found in each chapter. Meteor Crater, a 4.5 km2 impact crater that formed ˜50,000 years ago in northern Arizona, has prominent gully features on its steep walls that appear similar to some gullies found on Mars. At the crater bottom, there are over 30 meters of lake sediments from a lake that disappeared ˜10,000 to 11,000 years ago, indicating the transition from the Pleistocene to the current, drier climate. A combination of fieldwork, cosmogenic dating, and topographic analysis of LiDAR data show that debris flows, not seepage erosion and fluvial processes as previously suggested in the literature, drove gully incision during their formation period of ˜40,000 years before the onset of the Holocene. Runoff from bare bedrock source areas high on the crater wall cut into lower debris mantled slopes, where the runoff bulked up and transformed into debris flows that carried boulders down to ˜5 to 8 degree slopes, leaving distinct boulder lined levees and lobate tongues of terminal debris deposits

  7. Fejokoo Crater

    NASA Image and Video Library

    2017-03-17

    NASA's Dawn mission has found that craters on Ceres show a diversity of shapes that provide important clues about the structure of Ceres' subsurface. The bottom half of this pair of craters is called Fejokoo, named after the Nigerian god who supplied yams. The hexagonal shape of that 42-mile (68-kilometer) crater is probably due to the presence of fractures in the crust, along which the crater rims tend to align. Polygonal craters are frequent on Ceres. Most display six or seven sides, like in the case of Fejokoo, but a few nonagons -- nine-sided shapes -- have been discovered. Polygonal craters are also commonly found on other solar system bodies, such as Mars, Earth's moon and icy moons of giant planets. Dawn took this image on May 4, 2015, from an altitude of 915 miles (1,470 kilometers). The image has a resolution of 450 feet (140 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA21399

  8. Dunes in Darwin Crater

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03039 Dunes in Darwin Crater

    The dunes and sand deposits in this image are located on the floor of Darwin Crater.

    Image information: VIS instrument. Latitude 57.4S, Longitude 340.2E. 17 meter/pixel resolution.

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

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

  9. Landslide in a Crater

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The landslide in this VIS image is located inside an impact crater in the Elysium region of Mars. The unnamed crater is located at the margin of the volcanic flows from the Elysium Mons complex.

    Image information: VIS instrument. Latitude 1.2, Longitude 134 East (226 West). 19 meter/pixel resolution.

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

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

  10. Landslide in a Crater

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The landslide in this VIS image is located inside an impact crater in the Elysium region of Mars. The unnamed crater is located at the margin of the volcanic flows from the Elysium Mons complex.

    Image information: VIS instrument. Latitude 1.2, Longitude 134 East (226 West). 19 meter/pixel resolution.

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

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

  11. Crater Chaos

    NASA Image and Video Library

    2015-11-11

    This image captured by NASA 2001 Mars Odyssey spacecraft shows part of the interior of an unnamed crater in Arabia Terra. There are numerous hills and valleys in the crater, indicating depositional and erosional processes were active after the impact crater was formed. Orbit Number: 60714 Latitude: 38.7772 Longitude: 2.19471 Instrument: VIS Captured: 2015-08-21 22:51 http://photojournal.jpl.nasa.gov/catalog/PIA20090

  12. Tugaske Crater

    NASA Image and Video Library

    2015-07-07

    Today's VIS image shows part of Tugaske Crater. The northern margin of this crater has been modified from a circular form, most likely related to the tectonic activity of Claritas Fossae, where this crater is located. Additionally there are several landslide deposits in the crater, perhaps also formed by tectonic instability in the local region. Orbit Number: 59439 Latitude: -31.581 Longitude: 258.918 Instrument: VIS Captured: 2015-05-08 22:03 http://photojournal.jpl.nasa.gov/catalog/PIA19505

  13. Asteroids, Comets, Meteors 1991

    NASA Technical Reports Server (NTRS)

    Harris, Alan W. (Editor); Bowell, Edward (Editor)

    1992-01-01

    Papers from the conference are presented and cover the following topics with respect to asteroids, comets, and/or meteors: interplanetary dust, cometary atmospheres, atmospheric composition, comet tails, astronomical photometry, chemical composition, meteoroid showers, cometary nuclei, orbital resonance, orbital mechanics, emission spectra, radio astronomy, astronomical spectroscopy, photodissociation, micrometeoroids, cosmochemistry, and interstellar chemistry.

  14. Infrasound detection of meteors

    NASA Astrophysics Data System (ADS)

    ElGabry, M. N.; Korrat, I. M.; Hussein, H. M.; Hamama, I. H.

    2017-06-01

    Meteorites that penetrate the atmosphere generate infrasound waves of very low frequency content. These waves can be detected even at large distances. In this study, we analyzed the infrasound waves produced by three meteors. The October 7, 2008 TC3 meteor fell over the north Sudan Nubian Desert, the February 15, 2013 Russian fireball, and the February 6, 2016 Atlantic meteor near to the Brazil coast. The signals of these three meteors were detected by the infrasound sensors of the International Monitoring System (IMS) of the Comprehensive Test Ban Treaty Organization (CTBTO). The progressive Multi Channel Technique is applied to the signals in order to locate these infrasound sources. Correlation of the recorded signals in the collocated elements of each array enables to calculate the delays at the different array element relative to a reference one as a way to estimate the azimuth and velocity of the coming infrasound signals. The meteorite infrasound signals show a sudden change in pressure with azimuth due to its track variation at different heights in the atmosphere. Due to movement of the source, a change in azimuth with time occurs. Our deduced locations correlate well with those obtained from the catalogues of the IDC of the CTBTO.

  15. Meteor showers in review

    NASA Astrophysics Data System (ADS)

    Jenniskens, Peter

    2017-09-01

    Recent work on meteor showers is reviewed. New data is presented on the long duration showers that wander in sun-centered ecliptic coordinates. Since the early days of meteor photography, much progress has been made in mapping visual meteor showers, using low-light video cameras instead. Now, some 820,000 meteoroid orbits have been measured by four orbit surveys during 2007-2015. Mapped in sun-centered ecliptic coordinates in 5° intervals of solar longitude, the data show a number of long duration (>15 days) meteor showers that have drifting radiants and speeds with solar longitude. 18 showers emerge from the antihelion source and follow a drift pattern towards high ecliptic latitudes. 27 Halley-type showers in the apex source move mostly towards lower ecliptic longitudes, but those at high ecliptic latitudes move backwards. Also, 5 low-speed showers appear between the toroidal ring and the apex source, moving towards the antihelion source. Most other showers do not last long, or do not move much in sun-centered ecliptic coordinates. The surveys also detected episodic showers, which mostly document the early stages of meteoroid stream formation. New data on the sporadic background have shed light on the dynamical evolution of the zodiacal cloud.

  16. Bizarre Crater Mound

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 5 June 2003

    The height of the interior mound of sediment inside this crater exceeds the crater rim heights by 900 meters (3,000 ft). This is a confounding problem. How does all this material get inside this crater and actually rise higher than its holding chamber? What is this material? Where did it come from? Why is it still here? It is exactly these kinds of enigmas that makes Mars so very interesting.

    Image information: VIS instrument. Latitude 12.2, Longitude 26.3 East (333.7 West). 19 meter/pixel resolution.

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

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

  17. Gale Crater Mound

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    The eroded, layered deposit in Gale Crater is a mound of material rising 3 km above the crater floor. It has been sculpted by wind and possibly water to produce the dramatic landforms seen today. The origin of the sedimentary material that composes the mound remains a contested issue: was it produced from sedimentation in an ancient crater lake or by airfall onto dry land?

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

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

    Image information: VIS instrument. Latitude -5.1, Longitude 137.5 East (222.5 West). 19 meter/pixel resolution.

  18. Meteorite craters

    NASA Technical Reports Server (NTRS)

    Ivanov, B. A.; Bazilevskiy, A. T.

    1986-01-01

    The origin and formation of various types of craters, both on the Earth and on other planetary bodies, are discussed. Various models are utilized to depict various potential causes of the types and forms of meteorite craters in our solar system, and the geological structures are also discussed.

  19. Young Crater

    NASA Image and Video Library

    2012-11-12

    This image from NASA 2001 Mars Odyssey spacecraft shows a young crater. Dark radial spokes are created by the explosive blast of an impact event. With time, only thick ejecta near the rim of the crater will be visible, and dark spokes will disappear.

  20. Studies of Transient Meteor Activity

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter M. M.

    2002-01-01

    Meteoroids bombard Earth's atmosphere daily, but occasionally meteor rates increase to unusual high levels when Earth crosses the relatively fresh ejecta of comets. These transient events in meteor activity provide clues about the whereabouts of Earth-threatening long-period comets, the mechanisms of large-grain dust ejection from comets, and the particle composition and size distribution of the cometary ejecta. Observations of these transient events provide important insight in natural processes that determine the large grain dust environment of comets, in natural phenomena that were prevalent during the time of the origin of life, and in processes that determine the hazard of civilizations to large impacts and of man-made satellites to the periodic blizzard of small meteoroids. In this proposal, three tasks form a coherent program aimed at elucidating various aspects of meteor outbursts, with special reference to planetary astronomy and astrobiology. Task 1 was a ground-based effort to observe periods of transient meteor activity. This includes: (1) stereoscopic imaging of meteors during transient meteor events for measurements of particle size distribution, meteoroid orbital dispersions and fluxes; and (2) technical support for Global-MS-Net, a network of amateur-operated automatic counting stations for meteor reflections from commercial VHF radio and TV broadcasting stations, keeping a 24h vigil on the level of meteor activity for the detection of new meteor streams. Task 2 consisted of ground-based and satellite born spectroscopic observations of meteors and meteor trains during transient meteor events for measurements of elemental composition, the presence of organic matter in the meteoroids, and products generated by the interaction of the meteoroid with the atmosphere. Task 3 was an airborne effort to explore the 2000 Leonid meteor outbursts, which are anticipated to be the most significant of transient meteor activity events in the remainder of the

  1. Proctor Crater Dunes

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    This image, located near 30E and 47.5S, displays sand dunes within Proctor Crater. These dunes are composed of basaltic sand that has collected in the bottom of the crater. The topographic depression of the crater forms a sand trap that prevents the sand from escaping. Dune fields are common in the bottoms of craters on Mars and appear as dark splotches that lean up against the downwind walls of the craters. Dunes are useful for studying both the geology and meteorology of Mars. The sand forms by erosion of larger rocks, but it is unclear when and where this erosion took place on Mars or how such large volumes of sand could be formed. The dunes also indicate the local wind directions by their morphology. In this case, there are few clear slipfaces that would indicate the downwind direction. The crests of the dunes also typically run north-south in the image. This dune form indicates that there are probably two prevailing wind directions that run east and west (left to right and right to left).

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

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

  2. Fluidized Crater Ejecta Deposit

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) spacecraft continued to obtain high resolution images of the red planet into August 1998. At this time, each ground track (the portion of Mars available for MOC imaging on a given orbit) covers areas from about 40oN on the late afternoon side of the planet, up over the sunlit north polar cap, and down the early morning side of Mars to about 20oN latitude. Early morning and late afternoon views provide good shadowing to reveal subtle details on the martian surface. Views of Mars with such excellent lighting conditions will not be seen by MOC once MGS's Science Phasing Orbits end in mid-September 1998.

    The image shown here, MOC image 47903, was targeted on Friday afternoon (PDT), August 7, 1998. This picture of ejecta from a nameless 9.1 kilometer (5.7 mile)-diameter crater was designed to take full advantage of the present lighting conditions. When the image was taken (around 5:38 p.m. (PDT) on Saturday, August 8, 1998), the Sun had just risen and was only about 6o above the eastern horizon. With the Sun so low in the local sky, the contrast between sunlit and shadowed surfaces allowed new, subtle details to be revealed on the surface of the crater ejecta deposit.

    The crater shown here has ejecta of a type that was first identified in Mariner 9 and Viking Orbiter images as 'fluidized' ejecta. Ejecta is the material that is thrown out from the crater during the explosion that results when a meteor--piece of a comet or asteroid--collides with the planet. Fluidized ejecta is characterized by its lobate appearance, and sometimes by the presence of a ridge along the margin of the ejecta deposit. In the case of the crater shown here, there are two ridges that encircle the crater ejecta--this type of ejecta deposit is sometimes called a double-lobe rampart deposit. The MOC image shows that this particular crater also has 'normal' ejecta that occurs out on the plains, beyond the outermost ridge of

  3. Fluidized Crater Ejecta Deposit

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) spacecraft continued to obtain high resolution images of the red planet into August 1998. At this time, each ground track (the portion of Mars available for MOC imaging on a given orbit) covers areas from about 40oN on the late afternoon side of the planet, up over the sunlit north polar cap, and down the early morning side of Mars to about 20oN latitude. Early morning and late afternoon views provide good shadowing to reveal subtle details on the martian surface. Views of Mars with such excellent lighting conditions will not be seen by MOC once MGS's Science Phasing Orbits end in mid-September 1998.

    The image shown here, MOC image 47903, was targeted on Friday afternoon (PDT), August 7, 1998. This picture of ejecta from a nameless 9.1 kilometer (5.7 mile)-diameter crater was designed to take full advantage of the present lighting conditions. When the image was taken (around 5:38 p.m. (PDT) on Saturday, August 8, 1998), the Sun had just risen and was only about 6o above the eastern horizon. With the Sun so low in the local sky, the contrast between sunlit and shadowed surfaces allowed new, subtle details to be revealed on the surface of the crater ejecta deposit.

    The crater shown here has ejecta of a type that was first identified in Mariner 9 and Viking Orbiter images as 'fluidized' ejecta. Ejecta is the material that is thrown out from the crater during the explosion that results when a meteor--piece of a comet or asteroid--collides with the planet. Fluidized ejecta is characterized by its lobate appearance, and sometimes by the presence of a ridge along the margin of the ejecta deposit. In the case of the crater shown here, there are two ridges that encircle the crater ejecta--this type of ejecta deposit is sometimes called a double-lobe rampart deposit. The MOC image shows that this particular crater also has 'normal' ejecta that occurs out on the plains, beyond the outermost ridge of

  4. Optical fluxes and meteor properties of the camelopardalid meteor shower

    NASA Astrophysics Data System (ADS)

    Campbell-Brown, M. D.; Blaauw, R.; Kingery, A.

    2016-10-01

    Observations of the Camelopardalid meteor shower in May 2014 were obtained with six different sets of cameras, with limiting meteor magnitudes varying from -2M to +7M. Shower fluxes were calculated for each of the systems, from which the mass index of the shower was found to be 2.17 ± 0.04. Faint meteors in the shower were found to be stronger than average, ablating at lower altitudes than meteors at the same speed recorded with the same system, while the brightest meteors had higher ablation heights and were therefore weaker than typical meteors. These findings can be explained if large Camelopardalids are weak agglomerations of more refractory grains, which are easily disrupted in space and keep the shower supplied with small material and depleted in large material.

  5. Meteor signature interpretation

    SciTech Connect

    Canavan, G.H.

    1997-01-01

    Meteor signatures contain information about the constituents of space debris and present potential false alarms to early warnings systems. Better models could both extract the maximum scientific information possible and reduce their danger. Accurate predictions can be produced by models of modest complexity, which can be inverted to predict the sizes, compositions, and trajectories of object from their signatures for most objects of interest and concern.

  6. Buried Crater

    NASA Image and Video Library

    2002-12-04

    With a location roughly equidistant between two of the largest volcanic constructs on the planet, the fate of the approximately 50 km 31 mile impact crater in this image from NASA Mars Odyssey was sealed. It has been buried to the rim by lava flows. The MOLA context image shows pronounced flow lobes surrounding the crater, a clear indication of the most recent episode of volcanism that could have contributed to its infilling. Breaches in the rim are clearly evident in the image and suggest locations through which lavas could have flowed. These openings appear to be limited to the west side of the crater. Other craters in the area are nearly obliterated by the voluminous lava flows, further demonstrating one of the means by which Mars renews its surface. The MOLA context image shows pronounced flow lobes surrounding the crater, a clear indication of the most recent episode of volcanism that could have contributed to its infilling. Breaches in the rim are clearly evident in the image and suggest locations through which lavas could have flowed. These openings appear to be limited to the west side of the crater. Other craters in the area are nearly obliterated by the voluminous lava flows, further demonstrating one of the means by which Mars renews its surface. http://photojournal.jpl.nasa.gov/catalog/PIA04018

  7. Meteors in Australian Aboriginal Dreamings

    NASA Astrophysics Data System (ADS)

    Hamacher, Duane W.; Norris, Ray P.

    2010-06-01

    We present a comprehensive analysis of Australian Aboriginal accounts of meteors. The data used were taken from anthropological and ethnographic literature describing oral traditions, ceremonies, and Dreamings of 97 Aboriginal groups representing all states of modern Australia. This revealed common themes in the way meteors were viewed between Aboriginal groups, focusing on supernatural events, death, omens, and war. The presence of such themes around Australia was probably due to the unpredictable nature of meteors in an otherwise well-ordered cosmos.

  8. Locating the K/T boundary impact crater(s)

    NASA Astrophysics Data System (ADS)

    Bush, Susan M.

    Stratigraphic, mineralogical, chemical and isotopic evidence have led to the large (˜10-km) asteroid or comet impact theory as the cause of the Cretaceous period coming to an end. However, a suitable crater has not yet been found. Although the crater may have been destroyed because half of what was then the ocean floor has since been subducted, researchers are still hot on the trail of the impact site(s).A. R. Hildebrand and W. V. Boynton, Department of Planetary Sciences, University of Arizona, Tucson, believe that locating the original crater(s) would resolve the volcanism versus impact debate over what ended the Cretaceous period. Based on a large concentration of shocked mineral grains and the largest grains occurring in North America, and impact-wave deposits at the K/T boundary only from the Caribbean and southern North America, they suggest that the K/T boundary impact occurred between North and South America. They suggest the 300-km-diameter buried basement structure in the Columbia Basin as a possible K/T impact crater. The location of impact-wave deposits and possibly seismically triggered slumps also helped the two decide that impact(s) musthave occurred in the Caribbean region.

  9. Maunder Crater

    NASA Image and Video Library

    2002-06-17

    This image taken by NASA Mars Odyssey spacecraft shows a portion of Maunder Crater with a number of interesting features including a series of barchan dunes that are traveling from right to left and gullies.

  10. Crumpled Crater

    NASA Image and Video Library

    2015-03-30

    It is no secret that Mercury's surface is scarred by abundant tectonic deformation, the vast majority of which is due to the planet's history of cooling and contraction through time. Yet Mercury is also heavily cratered, and hosts widespread volcanic plains. So it's perhaps unsurprising that these three types of landform often intersect-literally-as shown in this scene. Here, an unnamed crater, about 7.5 km (4.7 mi.) in diameter was covered, and almost fully buried, by lava. At some point after, compression of the surface formed scarps and ridges in the area that, when they reached the buried crater, came to describe its curved outline. Many arcuate ridges on Mercury formed this way. In this high-resolution view, we can also see the younger, later population of smaller craters that pock-mark the surface. http://photojournal.jpl.nasa.gov/catalog/PIA19263

  11. Nicholson Crater

    NASA Image and Video Library

    2012-03-14

    There is a large deposit of material on the floor of Nicholson Crater, as seen in this image from NASA 2001 Mars Odyssey spacecraft. This pile of material appears to be undergoing erosion by the wind.

  12. Occia Crater

    NASA Image and Video Library

    2012-05-10

    This image from NASA Dawn spacecraft of asteroid Vesta shows Occia crater, located in Vesta Gegania quadrangle, in Vesta southern hemisphere. A distinctive butterfly pattern is seen consisting of two separate lobes of ejecta on the opposite sides.

  13. Cratered Crescent

    NASA Image and Video Library

    2006-05-25

    Quiet and cold, a crescent Tethys floats above the nearly edge-on rings of Saturn. The only surface features visible on Tethys 1,071 kilometers, or 665 miles across from this distance are a few impact craters

  14. Shackleton Crater

    NASA Image and Video Library

    This visualization, created using Lunar Reconnaissance Orbiter laser altimeter data, offers a view of Shackleton Crater located in the south pole of the moon. Thanks to these measurements, we now h...

  15. A Tale of 3 Craters

    NASA Technical Reports Server (NTRS)

    2004-01-01

    11 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image captures some of the complexity of the martian upper crust. Mars does not simply have an impact-cratered surface, it's upper crust is a cratered volume. Over time, older craters on Mars have been eroded, filled, buried, and in some cases exhumed and re-exposed at the martian surface. The crust of Mars is layered to depths of 10 or more kilometers, and mixed in with the layered bedrock are a variety of ancient craters with diameters ranging from a few tens of meters (a few tens of yards) to several hundred kilometers (more than one or two hundred miles).

    The picture shown here captures some of the essence of the layered, cratered volume of the upper crust of Mars in a very simple form. The image shows three distinct circular features. The smallest, in the lower right quarter of the image, is a meteor crater surrounded by a mound of material. This small crater formed within a layer of bedrock that once covered the entire scene, but today is found only in this small remnant adjacent to the crater. The intermediate-sized crater, west (left) of the small one, formed either in the next layer down--that is, below the layer in which the small crater formed--or it formed in some layers that are now removed, but was big enough to penetrate deeply into the rock that is near the surface today. The largest circular feature in the image, in the upper right quarter of the image, is still largely buried. It formed in layers of rock that are below the present surface. Erosion has brought traces of its rim back to the surface of Mars. This picture is located near 50.0oS, 77.8oW, and covers an area approximately 3 km (1.9 mi) across. Sunlight illuminates this October 2004 image from the upper left.

  16. Palikir Crater

    NASA Image and Video Library

    2016-10-27

    Today's VIS image is of Palikir Crater in Terra Sirenum. The inner rim of the crater is dissected with numerous gullies. In higher resolution images from other imagers these gullies are the location of changing linea, which appear to grow and retreat as seasons change. Orbit Number: 65311 Latitude: -41.6177 Longitude: 202.206 Instrument: VIS Captured: 2016-09-03 13:12 http://photojournal.jpl.nasa.gov/catalog/PIA21152

  17. Dividing Arizona

    ERIC Educational Resources Information Center

    Finkel, Ed

    2010-01-01

    Amid all the national attention on Arizona these past few months, largely due to Senate Bill 1070 empowering police to take "reasonable" steps to verify the immigration status of criminal suspects, the state's K12 district administrators have been wrestling with a unique segregation issue, as well. Over the past two years, all districts…

  18. Meteor Beliefs Project: Meteoric references in Ovid's Metamorphoses

    NASA Astrophysics Data System (ADS)

    Gheorghe, A. D.; McBeath, A.

    2003-10-01

    Three sections of Ovid's Metamorphoses are examined, providing further information on meteoric beliefs in ancient Roman times. These include meteoric imagery among the portents associated with the death of Julius Caesar, which we mentioned previously from the works of William Shakespeare (McBeath and Gheorghe, 2003b).

  19. James Joule and meteors

    NASA Astrophysics Data System (ADS)

    Hughes, David W.

    1989 was the hundredth anniversary of the death of James Prescott Joule, the Prescott being his mother's family name and the Joule, rhyming with cool, originating from the Derbyshire village of Youlgreave. Joule is rightly famous for his experimental efforts to establish the law of conservation of energy, and for the fact that J, the symbol known as the mechanical equivalent of heat, is named after him. Astronomically his "light has been hidden under a bushel". James Joule had a major influence on the physics of meteors.

  20. Oudemans Crater

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image of the interior of Oudemans Crater was taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) at 1800 UTC (1:00 p.m. EDT) on October 2, 2006, near 9.8 degrees south latitude, 268.5 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 20 meters (66 feet) across.

    Oudemans Crater is located at the extreme western end of Valles Marineris in the Sinai Planum region of Mars. The crater measures some 124 kilometers (77 miles) across and sports a large central peak.

    Complex craters like Oudemans are formed when an object, such as an asteroid or comet, impacts the planet. The size, speed and angle at which the object hits all determine the type of crater that forms. The initial impact creates a bowl-shaped crater and flings material (known as ejecta) out in all directions along and beyond the margins of the bowl forming an ejecta blanket. As the initial crater cavity succumbs to gravity, it rebounds to form a central peak while material along the bowl's rim slumps back into the crater forming terraces along the inner wall. If the force of the impact is strong enough, a central peak forms and begins to collapse back into the crater basin, forming a central peak ring.

    The uppermost image in the montage above shows the location of CRISM data on a mosaic taken by the Mars Odyssey spacecraft's Thermal Emission Imaging System (THEMIS). The CRISM data was taken inside the crater, on the northeast slope of the central peak.

    The lower left image is an infrared false-color image that reveals several distinctive deposits. The center of the image holds a ruddy-brown deposit that appears to correlates with a ridge running southwest to northeast. Lighter, buff-colored deposits occupy low areas interspersed within the ruddy-brown deposit. The southeast corner holds small hills that form part of the central peak complex.

    The lower right image shows spectral

  1. Oudemans Crater

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image of the interior of Oudemans Crater was taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) at 1800 UTC (1:00 p.m. EDT) on October 2, 2006, near 9.8 degrees south latitude, 268.5 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 20 meters (66 feet) across.

    Oudemans Crater is located at the extreme western end of Valles Marineris in the Sinai Planum region of Mars. The crater measures some 124 kilometers (77 miles) across and sports a large central peak.

    Complex craters like Oudemans are formed when an object, such as an asteroid or comet, impacts the planet. The size, speed and angle at which the object hits all determine the type of crater that forms. The initial impact creates a bowl-shaped crater and flings material (known as ejecta) out in all directions along and beyond the margins of the bowl forming an ejecta blanket. As the initial crater cavity succumbs to gravity, it rebounds to form a central peak while material along the bowl's rim slumps back into the crater forming terraces along the inner wall. If the force of the impact is strong enough, a central peak forms and begins to collapse back into the crater basin, forming a central peak ring.

    The uppermost image in the montage above shows the location of CRISM data on a mosaic taken by the Mars Odyssey spacecraft's Thermal Emission Imaging System (THEMIS). The CRISM data was taken inside the crater, on the northeast slope of the central peak.

    The lower left image is an infrared false-color image that reveals several distinctive deposits. The center of the image holds a ruddy-brown deposit that appears to correlates with a ridge running southwest to northeast. Lighter, buff-colored deposits occupy low areas interspersed within the ruddy-brown deposit. The southeast corner holds small hills that form part of the central peak complex.

    The lower right image shows spectral

  2. Holden Crater Dune Field

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    A common location for dune fields on Mars is in the basin of large craters. This dune field is located in Holden Crater at 25 degrees South atitude.

    Image information: VIS instrument. Latitude -25.5, Longitude 326.8 East (33.2 West). 19 meter/pixel resolution.

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

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

  3. Tikhonravov Crater Dust Avalanches

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Dust avalanches, also called slope streaks, occur on many Martian terrains. The deposition of airborne dust on surfaces causes a bright tone in the THEMIS VIS images. Any movement of the dust downhill, a dust avalanche, will leave behind a streak where the darker, dust-free surface is exposed.

    These dust avalanches are located within a small crater inside Tikhonravov Crater.

    Image information: VIS instrument. Latitude 12.6, Longitude 37.1 East (322.9 West). 36 meter/pixel resolution.

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

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

  4. Kaiser Crater DCS

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released July 29, 2004 This image shows two representations of the same infra-red image covering a portion of Kaiser Crater. On the left is a grayscale image showing surface temperature, and on the right is a false-color composite made from 3 individual THEMIS bands. The false-color image is colorized using a technique called decorrelation stretch (DCS), which emphasizes the spectral differences between the bands to highlight compositional variations.

    In this image, the basaltic sand dunes in bottom of Kaiser crater are colored a bright pink/magenta. The spectral features are clean and prominent on these dust-free surfaces and the dark color of the basaltic dunes helps them to absorb sunlight and produces higher surface temperatures, which also contributes to the image colors.

    Image information: IR instrument. Latitude -46.5, Longitude 20.3 East (339.7 West). 100 meter/pixel resolution.

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

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

  5. Upside Down Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 28 August 2003

    This image shows an area not too far south of Meridiani, the area where the mineral hematite was found on the Martian surface. In the center of the image the terrain becomes quite rugged, where a great amount of material has eroded away, leaving behind buttes and mesas. Note how some of the mesas are quite circular. This is an example of 'inverted terrain,' in which a topographically low feature, like a crater or a trench, becomes filled in with material. Later, the surrounding terrain erodes away while the feature protects the material filling it. These circular mesas are most likely inverted craters that were once holes in the ground.

    Image information: VIS instrument. Latitude -28.2, Longitude 8.7 East (351.3 West). 19 meter/pixel resolution.

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

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

  6. Tikhonravov Crater Dust Avalanches

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Dust avalanches, also called slope streaks, occur on many Martian terrains. The deposition of airborne dust on surfaces causes a bright tone in the THEMIS VIS images. Any movement of the dust downhill, a dust avalanche, will leave behind a streak where the darker, dust-free surface is exposed.

    These dust avalanches are located within a small crater inside Tikhonravov Crater.

    Image information: VIS instrument. Latitude 12.6, Longitude 37.1 East (322.9 West). 36 meter/pixel resolution.

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

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

  7. A geometric model for excavation and modification at terrestrial simple impact craters

    NASA Technical Reports Server (NTRS)

    Grieve, R. A. F.; Garvin, J. B.

    1984-01-01

    A geometric model for the excavation and modification stages of simple crater development is presented. Cavity modification is modelled from an analytical derivation of the dimensions of the so-called transient cavity (Dence, 1973; Dence et al., 1977). The final cavity as it appears in terrestrial craters and the primary elements of excavation are approximated by a variation of the so-called Z model. The applicability of the model is tested with data from the Meteor and Brent craters. In the case of Meteor, the modelled final crater diameter at the original ground plane is within 26 m of the observed value and the modelled breccia lens and the rim crest volumes of the final true crater are within 9.5 percent and 2.5 percent, respectively, of the observed values. The correspondence for the more degraded Brent crater is less precise.

  8. Three Craters

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] View the Movie Click on image to view the movie [figure removed for brevity, see original site] [figure removed for brevity, see original site] Three Craters: Above and Below Click on image for high resolution TIFF Three Craters: Below and Above Click on image for high resolution TIFF

    This computer graphic image shows three craters in the eastern Hellas region of Mars containing concealed glaciers detected by radar. The image shows how the surface looks today with the ice covered with a layer of Martian soil. The image was created using image data from the Context Camera on the Mars Reconnaissance Orbiter (MRO) spacecraft combined with results from the SHARAD radar sounder on MRO and HRSC digital elevation map from the Mars Express spacecraft. The color of the Martian surface and ice was estimated from MRO HiRISE color images of other Martian craters and the polar ice caps. The buried ice in these craters as measured by SHARAD is 250 meter thick on the upper crater and 300 and 450 meters on the middle and lower levels respectively. Each image is 20 km (12.8 mi.) across and extends to 50 km (32 mi) in the distance.

    Recent measurements from the Mars Reconnaissance Orbiter SHARAD radar sounder have detected large amounts of water ice in such deposits over widespread areas, arguing for the flow of glacial-like structures on Mars in the relatively recent geologic past. This suggests that snow and ice accumulated on higher topography, flowed downhill and is now protected from sublimation by a layer of rock debris and dust. Furrows and ridges on the surface were caused by deforming ice.

    About the Movie The movie begins with a view of how the surface looks today. A blue line is drawn on the image and an artist's concept then reveals what the ice may look like underneath. The movie was created using image data from the Context Camera on the Mars Reconnaissance Orbiter (MRO) spacecraft combined with results

  9. Meridiani Craters

    NASA Technical Reports Server (NTRS)

    2004-01-01

    26 December 2004 A little over 11 months ago, the Mars Exploration Rover, Opportunity, landed on Meridiani Planum. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small portion of Meridiani Planum -- too far from the rover for it to investigate--that has been peppered with small impact craters. The majority of craters, particularly those in the lower half of the image, are secondary impacts caused by the landing of rock and debris ejected from a much larger impact crater, located elsewhere in the region. The large, nearly circular depression at the top center of the image is the site of a much older crater that was filled and almost completely buried beneath the plains. As result of the rover's work in Meridiani Planum, it is now known that the bright rims and walls of the craters are, at least in part, exposures of sedimentary rock. The dark material covering the plains, according to rover results, is mostly very fine sand plus millimeter-sized granules. This picture covers an area about 3 km (1.9 mi) across, and is located near 2.5oS, 3.3oW. Sunlight illuminates the scene from the left.

  10. Hakumyi Crater

    NASA Image and Video Library

    2017-07-06

    NASA's Dawn spacecraft took this image of Hakumyi Crater on Ceres, visible left of center. The crater is named after a Paraguayan, Brazilian and Bolivian spirit said to be helpful in gardening. Hakumyi, 18 miles (29 kilometers) in diameter, is located about 43 miles (70 kilometers) west of Ernutet Crater. Ernutet is where scientists found evidence of organic material, thanks to Dawn's visible and infrared mapping spectrometer. Evidence for organics was also found at the 4-mile (6.5 kilometer) wide fresh crater on the southern rim of Hakumyi and on the lobe-shaped flow of material that runs into Hakumyi. These two features look relatively young in comparison to the rest of Hakumyi Crater, whose rims and overall shape are subdued. The lobate flow is reminiscent of the Type I flows identified in multiple places at high latitudes on Ceres, and suggests a significant amount of ice near the surface. Dawn took this image on August 20, 2015, from 915 miles (1,470 kilometers) altitude. The center coordinates of this image are 48.9 degrees north latitude and 27.0 degrees east longitude. https://photojournal.jpl.nasa.gov/catalog/PIA21413

  11. Dantu Crater

    NASA Image and Video Library

    2017-06-27

    This image from NASA's Dawn spacecraft shows Dantu Crater, which is 78 miles (126 kilometers) across. Its shape is reminiscent of Occator Crater -- in particular, they both have shallow floors and central pits. This suggests melting and possibly some hydrothermal activity occurred following impact that formed Dantu. Part of the energy generated by the impact would have been turned into heat. The relatively warm temperatures found at the low latitudes of Dantu and Occator make it easier for Ceres' ice-rich material to melt as a consequence of impact-generated heat. The unnamed crater seen below Dantu in this image is smaller and has a much rougher floor. This is because the smaller impact event would not have generated as much heat. The numerous bright spots found across the crater suggest bright material may be just below the surface, exposed through small impacts and landslides. Ejected material from Dantu extends up to Kerwan crater, with a dark color reminiscent of material that came from Occator. Dantu was named for the Ghanaian god associated with the planting of the corn. This picture was taken by the Dawn framing camera on September 25, 2015, from 915 miles (1,470 kilometers) altitude. The center coordinates of this picture are 22 degrees north latitude, 133 degrees east longitude. https://photojournal.jpl.nasa.gov/catalog/PIA21412

  12. Inamahari Crater

    NASA Image and Video Library

    2017-04-13

    Inamahari Crater on Ceres, the large well-defined crater at the center of this image, is one of the sites where scientists have discovered evidence for organic material. The crater, 42 miles (68 kilometers) in diameter, presents other interesting attributes. It has a polygonal shape and an association with another crater of similar size and geometry called Homshuk (center right), although the latter appears eroded and is likely older. Future studies of Inamahari crater and surroundings may help uncover the mechanisms involved in the exposure of organic material onto Ceres' surface. Inamahari was named for a pair of male and female deities from the ancient Siouan tribe of South Carolina, invoked for a successful sowing season. Homshuk refers to the spirit of corn (maize) from the Popoluca peoples of southern Mexico. Inamahari is located at 14 degrees north latitude, 89 degrees east longitude. This picture was taken by NASA's Dawn on September 25, 2015 from an altitude of about 915 miles (1,470 kilometers). It has a resolution of 450 feet (140 meters) per pixel. https://photojournal.jpl.nasa.gov/catalog/PIA21402

  13. Meteor fireball sounds identified

    NASA Technical Reports Server (NTRS)

    Keay, Colin

    1992-01-01

    Sounds heard simultaneously with the flight of large meteor fireballs are electrical in origin. Confirmation that Extra/Very Low Frequency (ELF/VLF) electromagnetic radiation is produced by the fireball was obtained by Japanese researchers. Although the generation mechanism is not fully understood, studies of the Meteorite Observation and Recovery Project (MORP) and other fireball data indicate that interaction with the atmosphere is definitely responsible and the cut-off magnitude of -9 found for sustained electrophonic sounds is supported by theory. Brief bursts of ELF/VLF radiation may accompany flares or explosions of smaller fireballs, producing transient sounds near favorably placed observers. Laboratory studies show that mundane physical objects can respond to electrical excitation and produce audible sounds. Reports of electrophonic sounds should no longer be discarded. A catalog of over 300 reports relating to electrophonic phenomena associated with meteor fireballs, aurorae, and lightning was assembled. Many other reports have been cataloged in Russian. These may assist the full solution of the similar long-standing and contentious mystery of audible auroral displays.

  14. Stop Sign Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    With its rim eroded off by catastrophic floods in Tiu Vallis and its strangely angular shape, this 12 km diameter crater looks vaguely like a stop sign.

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

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

    Image information: VIS instrument. Latitude 8.6, Longitude 329.2 East (30.8 West). 19 meter/pixel resolution.

  15. Stop Sign Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    With its rim eroded off by catastrophic floods in Tiu Vallis and its strangely angular shape, this 12 km diameter crater looks vaguely like a stop sign.

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

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

    Image information: VIS instrument. Latitude 8.6, Longitude 329.2 East (30.8 West). 19 meter/pixel resolution.

  16. Concentric Crater Fill

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    The bizarre patterns on the floor of this crater in Nilosyrtis Mensae defy an easy explanation. At 34 degrees north latitude, this location hardly qualifies as 'Arctic' yet it is likely that some form of periglacial process possibly combined with the vaporization of ground ice is responsible for this intriguing landscape.

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

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

    Image information: VIS instrument. Latitude 10.3, Longitude 24.5 East (284.5 West). 19 meter/pixel resolution.

  17. Weepy Crater

    NASA Technical Reports Server (NTRS)

    2006-01-01

    11 August 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies -- all of which head at the same level -- on a south mid-latitude crater wall. At the 6 meters (20 feet) per pixel scale at which this image was obtained, the gullies almost appear as if they are the product of a 'weeping layer,' a porous layer of rock through which a liquid such as water may have percolated until it came to the martian surface at this crater wall, then flowed downslope, toward the crater floor.

    Location near: 34.0oS, 208.4oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

  18. Meridiani Crater

    NASA Technical Reports Server (NTRS)

    2005-01-01

    31 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a crater formed in light-toned, layered, sedimentary rocks in Meridiani Planum. This crater is located approximately 55 kilometers (34 miles) southwest of the Mars Exploration Rover, Opportunity, site. Erosion of sedimentary rock layers around the crater rim has caused an uneven retreat, resulting in the formation of U-shaped alcoves where undermining and collapse have occurred. Dark material in this scene is probably sand and granules, similar to the dark surfaces explored by the Opportunity rover.

    Location near: 3.1oS, 5.8oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Spring

  19. Terby Crater

    NASA Image and Video Library

    2002-12-13

    Perched on the northern rim of the enormous Hellas Basin, Terby Crater, imaged by NASA Mars Odyssey, is host to an impressive range of landforms. As is common for many Martian craters, Terby has been filled with layered material, presumably sediments. The process of erosion has exposed some of these layers along with strange, rectilinear ridges. Sinuous channels, collapse pits, and a scoured-looking cap rock are some of the other interesting landforms in Terby. Such a variety of landforms attests to a diversity of rock types and geologic processes in the relatively small area of this THEMIS image. http://photojournal.jpl.nasa.gov/catalog/PIA04024

  20. Crater Appeal

    ERIC Educational Resources Information Center

    Mueller, Michael P.; Valderrama, Paige

    2006-01-01

    For many years, the planet Mars was nothing more than a little red dot in a sea of stars and a blur in many science classrooms. Recent focus on the planet, however, has led to incredible teaching opportunities, such as the Mars Student Imaging Project (MSIP) facilitated by Arizona State University's Mars Education Program. The MSIP curriculum…

  1. Crater Appeal

    ERIC Educational Resources Information Center

    Mueller, Michael P.; Valderrama, Paige

    2006-01-01

    For many years, the planet Mars was nothing more than a little red dot in a sea of stars and a blur in many science classrooms. Recent focus on the planet, however, has led to incredible teaching opportunities, such as the Mars Student Imaging Project (MSIP) facilitated by Arizona State University's Mars Education Program. The MSIP curriculum…

  2. The Chelyabinsk meteor

    NASA Astrophysics Data System (ADS)

    Popova, O.; Jenniskens, P.; Shuvalov, V.; Emel'yanenko, V.; Rybnov, Y.; Kharlamov, V.; Kartashova, A.; Biryukov, E.; Khaibrakhmanov, S.

    2014-07-01

    A review is given about what was learned about the 0.5-Mt Chelyabinsk airburst of 15 February 2013 by field studies, the analysis of recovered meteorites, and numerical models of meteoroid fragmentation and airburst propagation. Previous events with comparable or larger energy in recent times include only the 0.5-Mt -sized 3 August 1963 meteor over the south Atlantic, for which only an infrasound signal was recorded, and the famous Tunguska impact of 1908. Estimates of the initial kinetic energy of the Tunguska impact range from 3 to 50 Mt, due to the lack of good observations at the time. The Chelyabinsk event is much better documented than both, and provides a unique opportunity to calibrate the different approaches used to model meteoroid entry and calculate the damaging effects of a shock wave from a large meteoroid impact. A better understanding of what happened might help future impact hazard mitigation efforts by calibrating models of what might happen under somewhat different circumstances. The initial kinetic energy is estimated from infrasonic signals and the fireball's lightcurve, as well as the extent of the glass damage on the ground. Analysis of video observations of the fireball and the shadow movements provided an impact trajectory and a record of the meteor lightcurve, which describes how that energy was deposited in the atmosphere. Ablation and fragmentation scenarios determine the success of attempts to reproduce the observed meteor lightcurve and deceleration profile by numerical modeling. There was almost no deceleration until peak brightness. Meteoroid fragmentation occurred in different forms, some part of the initial mass broke in well separated fragments, the surviving fragments falling on the ground as meteorites. The specific conditions during energy deposition determined the fraction of surviving mass. The extent of the glass damage was mapped by visiting over 50 villages in the area. A number of numerical simulations were conducted that

  3. Antarctic meteor observations using the Davis MST and meteor radars

    NASA Astrophysics Data System (ADS)

    Holdsworth, David A.; Murphy, Damian J.; Reid, Iain M.; Morris, Ray J.

    2008-07-01

    This paper presents the meteor observations obtained using two radars installed at Davis (68.6°S, 78.0°E), Antarctica. The Davis MST radar was installed primarily for observation of polar mesosphere summer echoes, with additional transmit and receive antennas installed to allow all-sky interferometric meteor radar observations. The Davis meteor radar performs dedicated all-sky interferometric meteor radar observations. The annual count rate variation for both radars peaks in mid-summer and minimizes in early Spring. The height distribution shows significant annual variation, with minimum (maximum) peak heights and maximum (minimum) height widths in early Spring (mid-summer). Although the meteor radar count rate and height distribution variations are consistent with a similar frequency meteor radar operating at Andenes (69.3°N), the peak heights show a much larger variation than at Andenes, while the count rate maximum-to-minimum ratios show a much smaller variation. Investigation of the effects of the temporal sampling parameters suggests that these differences are consistent with the different temporal sampling strategies used by the Davis and Andenes meteor radars. The new radiant mapping procedure of [Jones, J., Jones, W., Meteor radiant activity mapping using single-station radar observations, Mon. Not. R. Astron. Soc., 367(3), 1050-1056, doi: 10.1111/j.1365-2966.2006.10025.x, 2006] is investigated. The technique is used to detect the Southern delta-Aquarid meteor shower, and a previously unknown weak shower. Meteoroid speeds obtained using the Fresnel transform are presented. The diurnal, annual, and height variation of meteoroid speeds are presented, with the results found to be consistent with those obtained using specular meteor radars. Meteoroid speed estimates for echoes identified as Southern delta-Aquarid and Sextantid meteor candidates show good agreement with the theoretical pre-atmospheric speeds of these showers (41 km s -1 and 32 km s -1

  4. Meteoric water in magmas

    USGS Publications Warehouse

    Friedman, I.; Lipman, P.W.; Obradovich, J.D.; Gleason, J.D.; Christiansen, R.L.

    1974-01-01

    Oxygen isotope analyses of sanidine phenocrysts from rhyolitic sequences in Nevada, Colorado, and the Yellowstone Plateau volcanic field show that ??18O decreased in these magmas as a function of time. This decrease in ??18O may have been caused by isotopic exchange between the magma and groundwater low in 18O. For the Yellowstone Plateau rhyolites, 7000 cubic kilometers of magma could decrease in ??18O by 2 per mil in 600,000 years by reacting with water equivalent to 3 millimeters of precipitation per year, which is only 0.3 percent of the present annual precipitation in this region. The possibility of reaction between large magmatic bodies and meteoric water at liquidus temperatures has major implications in the possible differentiation history of the magma and in the generation of ore deposits.

  5. Meteoric water in magmas.

    PubMed

    Friedman, I; Lipman, P W; Obradovich, J D; Gleason, J D; Christiansen, R L

    1974-06-07

    Oxygen isotope analyses of sanidine phenocrysts from rhyolitic sequences in Nevada, Colorado, and the Yellowstone Plateau volcanic field show that delta(18)O decreased in these magmas as a function of time. This decrease in delta(18)O may have been caused by isotopic exchange between the magma and groundwater low in (18)O. For the Yellowstone Plateau rhyolites, 7000 cubic kilometers of magma could decrease in delta(18)O by 2 per mil in 600,000 years by reacting with water equivalent to 3 millimeters of precipitation per year, which is only 0.3 percent of the present annual precipitation in this region. The possibility of reaction between large magmatic bodies and meteoric water at liquidus temperatures has major implications in the possible differentiation history of the magma and in the generation of ore deposits.

  6. Juling Crater

    NASA Image and Video Library

    2017-08-25

    This high-resolution image of Juling Crater on Ceres reveals, in exquisite detail, features on the rims and crater floor. The crater is about 1.6 miles (2.5 kilometers) deep and the small mountain, seen left of the center of the crater, is about 0.6 miles (1 kilometers) high. The many features indicative of the flow of material suggest the subsurface is rich in ice. The geological structure of this region also generally suggests that ice is involved. The origin of the small depression seen at the top of the mountain is not fully understood but might have formed as a consequence of a landslide, visible on the northeastern flank. Dawn took this image during its extended mission on August 25, 2016, from its low-altitude mapping orbit at a distance of about 240 miles (385 kilometers) above the surface. The center coordinates of this image are 36 degrees south latitude, 167 degrees east longitude. Juling is named after the Sakai/Orang Asli spirit of the crops from Malaysia. NASA's Dawn spacecraft acquired this picture on August 24, 2016. The image was taken during Dawn's extended mission, from its low altitude mapping orbit at about 240 miles (385 kilometers) above the surface. The center coordinates of this image are 38 degrees south latitude, 165 degrees east longitude. https://photojournal.jpl.nasa.gov/catalog/PIA21754

  7. Tawals Crater

    NASA Image and Video Library

    2017-08-03

    This image taken by NASA's Dawn spacecraft shows a region located next to the northwestern rim of Urvara Crater on Ceres. This terrain displays a rugged texture also found within Urvara. Multiple Dawn observations, in particular neutron spectroscopy (which measures the hydrogen content in the regolith) and flow features, have shown that water ice is present near the surface above 40 degrees north latitude, where these features are found. Therefore, the rugged texture may result from the high strength exhibited by ice at the temperatures found at mid- and high latitudes on Ceres. The prominent crater (5.0 miles, 8.8 kilometers in diameter) at right in this picture is called Tawals. Its sharp rim suggests it was created by a relatively recent impact into a relatively strong material. A different view of this crater can be found in PIA20941. Tawals Crater is named after the Polish god of the fields and the tilling. Dawn took this image during its extended mission on August 25, 2016, from its low-altitude mapping orbit, or LAMO, at a distance of about 240 miles (385 kilometers) above the surface. The center coordinates of this image are 40 degrees south latitude, 237 degrees east longitude. https://photojournal.jpl.nasa.gov/catalog/PIA21750

  8. Lyell Crater

    NASA Image and Video Library

    2015-04-15

    This image captured by NASA 2001 Mars Odyssey spacecraft shows numerous gullies are visible on the cliff face of a depression within the floor of Lyell Crater. Orbit Number: 58444 Latitude: -69.3387 Longitude: 346.015 Instrument: VIS Captured: 2015-02-16 00:08 http://photojournal.jpl.nasa.gov/catalog/PIA19280

  9. Doublet Crater

    NASA Image and Video Library

    2011-02-14

    This doublet crater was formed when two meteorites impacted at the same time. The shock waves interact to form the straight central rim and the wings of ejecta on the outside of the rims. This image is from NASA Mars Odyssey.

  10. Kuiper Crater

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The Mariner 10 Television-Science Team has proposed the name 'Kuiper' for this very conspicuous bright Mercury crater (top center) on the rim of a larger older crater. Prof. Gerard P. Kuiper, a pioneer in planetary astronomy and a member of the Mariner 10 TV team, died December 23, 1973, while the spacecraft was enroute to Venus and Mercury. Mariner took this picture (FDS 27304) from 88,450 kilometers (55,000 miles) some 2 1/2 hours before it passed Mercury on March 29. The bright-floored crater, 41 kilometers (25 miles) in diameter, is the center of a very large bright are which could be seen in pictures sent from Mariner 10 while Mercury was more than two million miles distant. The larger crater is 80 kilometers (50 miles) across.

    The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

    Image Credit: NASA/JPL/Northwestern University

  11. Kuiper Crater

    NASA Image and Video Library

    1999-10-08

    NASA Mariner 10 took this picture some 2 1/2 hours before it passed Mercury on March 29, 1974. The bright-floored crater is the center of a very large bright area which could be seen in pictures from more than two million miles distant

  12. Artificial meteor test towards: On-demand meteor shower

    NASA Astrophysics Data System (ADS)

    Abe, S.; Okajima, L.; Sahara, H.; Watanabe, T.; Nojiri, Y.; Nishizono, T.

    2016-01-01

    An arc-heated wind tunnel is widely used for ground-based experiments to simulate environments of the planetary atmospheric entry under hypersonic and high-temperature conditions. In order to understand details of a meteor ablation such as temperature, composition ratio and fragmentation processes, the artificial meteor test was carried out using a JAXA/ISAS arc-heated wind tunnel. High-heating rate around 30 MW/m2 and High-enthalpy conditions, 10000 K arc-heated flow at velocity around 6 km/s were provided. Newly developed artificial metallic meteoroids and real meteorites such as Chelyabinsk were used for the ablation test. The data obtained by near-ultraviolet and visible spectrograph (200 and 1100nm) and high-speed camera (50 μs) have been examined to develop more efficient artificial meteor materials. We will test artificial meteors from a small satellite in 2018.

  13. Two slow meteors with spectra

    NASA Astrophysics Data System (ADS)

    Dubs, Martin; Sposetti, Stefano; Spinner, Roger; Booz, Beat

    2017-01-01

    On January 2, 2017 two peculiar meteors (M20170102_001216 and M20170102_015202) were observed by several stations in Switzerland. Both had a long duration, slow velocity, similar brightness and a very similar radiant. As they appeared in a time interval of 100 minutes, a satellite was suspected as a possible origin of these two observations. A closer inspection however showed that this interpretation was incorrect. The two objects were slow meteors. Spectra were taken from both objects, which were nearly identical. Together this points to a common origin of the two meteors.

  14. Pursuing a historical meteor shower

    NASA Astrophysics Data System (ADS)

    Watanabe, Jun-Ichi; Sato, Mikiya; Kasuga, Toshihiro

    2006-11-01

    The strong outburst of the Phoenicids was witnessed by people in a Japanese expedition ship, Soya, in 1956. After that, this meteor shower has never been observed at this activity level. Although its parent comet has not been strictly identified, the possible candidate was the comet D/1819W1 (Blanpain) which appeared only once in 1819. A newly discovered asteroid 2003WY25 becomes a clue to the mystery of this meteor shower. We introduce our result on the investigation of this meteor shower on the basis of the dust trail theory.

  15. Gullies on Martian Crater (THEMIS)

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This visible-light image, taken by the thermal emission imaging system on NASA's 2001 Mars Odyssey spacecraft, indicates that gullies on martian crater walls may be carved by liquid water melting from remnant snow packs. The gullies in the top right-center appear to emerge from beneath and within a gradually disappearing blanket of snow. The current snow pack in this crater (located at 43 degrees south, 214 degrees east) appears to remain only on the cold, pole facing crater wall (top). On the less-shaded, warmer sides of the crater (left), the snow cover has completely disappeared, leaving the gullies exposed. The image shows an area 14.8 kilometers (9.2 miles) by 21.6 kilometers (13.4 miles). North is toward the top, and illumination is from the left.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The thermal emission imaging system was provided by Arizona State University, Tempe. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  16. Exhuming Craters in a Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    12 December 2004 Burial and exhumation of impact craters, and their destruction by erosion, are common and repeated themes all over the surface of Mars. Many craters in western Arabia Terra exhibit light-toned, layered outcrops of ancient sedimentary rock. Like the sedimentary rocks explored further to the south in Meridiani Planum by the Opportunity Mars Exploration Rover (MER-B), these intracrater sedimentary rocks may have been deposited in water. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example of light-toned sedimentary rocks outcropping in a crater that is much farther north than most of the similar examples in western Arabia. This one is located near 36.6oN, 1.4oW, and shows several old impact craters in various states of erosion and exhumation from beneath and within the sedimentary rock materials. The image covers an area approximately 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.

  17. Geologic map of the eastern quarter of the Flagstaff 30’ x 60’ quadrangle, Coconino County, northern Arizona

    USGS Publications Warehouse

    Billingsley, George H.; Block, Debra L.; Hiza-Redsteer, Margaret

    2014-01-01

    The eastern quarter of the Flagstaff 30′ x 60′ quadrangle includes eight USGS 1:24,000-scale quadrangles in Coconino County, northern Arizona (fig. 1, map sheet): Anderson Canyon, Babbitt Wash, Canyon Diablo, Grand Falls, Grand Falls SE, Grand Falls SW, Grand Falls NE, and Meteor Crater. The map is bounded by lat 35° to 35°30′ N. and long 111° to 111°15′ W. and is on the southern part of the Colorado Plateaus geologic province (herein Colorado Plateau). Elevations range from 4,320 ft (1,317 m) at the Little Colorado River in the northwest corner of the map area to about 6,832 ft (2,082 m) at the southwest corner of the map. This geologic map provides an updated geologic framework for the eastern quarter of the Flagstaff 30′ x 60′ quadrangle and is adjacent to two other recent geologic maps, the Cameron and Winslow 30′ x 60′ quadrangles (Billingsley and others, 2007, 2013). This geologic map is the product of a cooperative effort between the U.S. Geological Survey (USGS) and the Navajo Nation. It provides geologic information for resource management officials of the U.S. Forest Service, the Arizona Game and Fish Department, and the Navajo Nation Reservation (herein the Navajo Nation). Funding for the map was provided by the USGS geologic mapping program, Reston, Virginia. Field work on the Navajo Nation was conducted under a permit from the Navajo Nation Minerals Department. Any persons wishing to conduct geologic investigations on the Navajo Nation must first apply for, and receive, a permit from the Navajo Nation Minerals Department, P.O. Box 1910, Window Rock, Arizona 86515, telephone (928) 871-6587.

  18. Meteor Beliefs Project: Seven years and counting

    NASA Astrophysics Data System (ADS)

    McBeath, A.; Drobnock, G. J.; Gheorghe, A. D.

    2010-04-01

    The Meteor Beliefs Project's seventh anniversary is celebrated with an eclectic mixture of meteor beliefs from the 1799 Leonids in Britain, the folkloric link between meteors and wishing in some Anglo-American sources, how a meteoric omen came to feature in Nathaniel Hawthorne's 1850 novel The Scarlet Letter, and a humorous item from the satirical magazine Punch in 1861, all helping to show how meteor beliefs can be transformed by different parts of society.

  19. Galle Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 19 June 2002) The Science This image is of part of Galle Crater, located at 51.9S, 29.5W. This image was taken far enough south and late enough into the southern hemisphere fall to catch observe water ice clouds partially obscuring the surface. The most striking aspect of the surface is the dissected layered unit to the left in the image. Other areas also appear to have layering, but they are either more obscured by clouds or are less well defined on the surface. The layers appear to be mostly flat lying and layer boundaries appear as topographic lines would on a map, but there are a few areas where it appears that these layers have been deformed to some level. Other areas of the image contain rugged, mountainous terrain as well as a separate pitted terrain where the surface appears to be a separate unit from the mountains and the layered terrain. The Story Galle Crater is officially named after a German astronomer who, in 1846, was the first to observe the planet Neptune. It is better known, however, as the 'Happy Face Crater.' The image above focuses on too small an area of the crater to see its beguiling grin, but you can catch the rocky line of a 'half-smile' in the context image to the right (to the left of the red box). While water ice clouds make some of the surface harder to see, nothing detracts from the fabulous layering at the center left-hand edge of the image. If you click on the above image, the scalloped layers almost look as if a giant knife has swirled through a landscape of cake frosting. These layers, the rugged, mountains near them, and pits on the surface (upper to middle section of the image on the right-hand side) all create varying textures on the crater floor. With such different features in the same place, geologists have a lot to study to figure out what has happened in the crater since it formed.

  20. Galle Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 19 June 2002) The Science This image is of part of Galle Crater, located at 51.9S, 29.5W. This image was taken far enough south and late enough into the southern hemisphere fall to catch observe water ice clouds partially obscuring the surface. The most striking aspect of the surface is the dissected layered unit to the left in the image. Other areas also appear to have layering, but they are either more obscured by clouds or are less well defined on the surface. The layers appear to be mostly flat lying and layer boundaries appear as topographic lines would on a map, but there are a few areas where it appears that these layers have been deformed to some level. Other areas of the image contain rugged, mountainous terrain as well as a separate pitted terrain where the surface appears to be a separate unit from the mountains and the layered terrain. The Story Galle Crater is officially named after a German astronomer who, in 1846, was the first to observe the planet Neptune. It is better known, however, as the 'Happy Face Crater.' The image above focuses on too small an area of the crater to see its beguiling grin, but you can catch the rocky line of a 'half-smile' in the context image to the right (to the left of the red box). While water ice clouds make some of the surface harder to see, nothing detracts from the fabulous layering at the center left-hand edge of the image. If you click on the above image, the scalloped layers almost look as if a giant knife has swirled through a landscape of cake frosting. These layers, the rugged, mountains near them, and pits on the surface (upper to middle section of the image on the right-hand side) all create varying textures on the crater floor. With such different features in the same place, geologists have a lot to study to figure out what has happened in the crater since it formed.

  1. Review of amateur meteor research

    NASA Astrophysics Data System (ADS)

    Rendtel, Jürgen

    2017-09-01

    Significant amounts of meteor astronomical data are provided by amateurs worldwide, using various methods. This review concentrates on optical data. Long-term meteor shower analyses based on consistent data are possible over decades (Orionids, Geminids, κ-Cygnids) and allow combination with modelling results. Small and weak structures related to individual stream filaments of cometary dust have been analysed in both major and minor showers (Quadrantids, September ε-Perseids), providing feedback to meteoroid ejection and stream evolution processes. Meteoroid orbit determination from video meteor networks contributes to the improvement of the IAU meteor data base. Professional-amateur cooperation also concerns observations and detailed analysis of fireball data, including meteorite ground searches.

  2. Centrifuge impact cratering experiment 5

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Transient crates motions, cratering flow fields, crates dynamics, determining impact conditions from total crater welt, centrifuge quarter-space cratering, and impact cratering mechanics research is documented.

  3. Gusev Crater

    NASA Image and Video Library

    2003-03-13

    This mosaic of daytime infrared images of Gusev Crater, taken by NASA Mars Odyssey spacecraft, has been draped over topography data obtained by NASA Mars Global Surveyor. The daytime temperatures range from approximately minus 45 degrees C (black) to minus 5 degrees C (white). The temperature differences in these daytime images are due primarily to lighting effects, where sunlit slopes are warm (bright) and shadowed slopes are cool (dark). Gusev crater is a potential landing site for the Mars Exploration Rovers. The large ancient river channel of Ma'Adim that once flowed into Gusev can be seen at the top of the mosaic. This image mosaic covers an area approximately 180 kilometers (110 miles) on each side centered near 14 degrees S, 175 degrees E, looking toward the south in this simulated view. http://photojournal.jpl.nasa.gov/catalog/PIA04260

  4. Coded continuous wave meteor radar

    NASA Astrophysics Data System (ADS)

    Vierinen, Juha; Chau, Jorge L.; Pfeffer, Nico; Clahsen, Matthias; Stober, Gunter

    2016-03-01

    The concept of a coded continuous wave specular meteor radar (SMR) is described. The radar uses a continuously transmitted pseudorandom phase-modulated waveform, which has several advantages compared to conventional pulsed SMRs. The coding avoids range and Doppler aliasing, which are in some cases problematic with pulsed radars. Continuous transmissions maximize pulse compression gain, allowing operation at lower peak power than a pulsed system. With continuous coding, the temporal and spectral resolution are not dependent on the transmit waveform and they can be fairly flexibly changed after performing a measurement. The low signal-to-noise ratio before pulse compression, combined with independent pseudorandom transmit waveforms, allows multiple geographically separated transmitters to be used in the same frequency band simultaneously without significantly interfering with each other. Because the same frequency band can be used by multiple transmitters, the same interferometric receiver antennas can be used to receive multiple transmitters at the same time. The principles of the signal processing are discussed, in addition to discussion of several practical ways to increase computation speed, and how to optimally detect meteor echoes. Measurements from a campaign performed with a coded continuous wave SMR are shown and compared with two standard pulsed SMR measurements. The type of meteor radar described in this paper would be suited for use in a large-scale multi-static network of meteor radar transmitters and receivers. Such a system would be useful for increasing the number of meteor detections to obtain improved meteor radar data products.

  5. Letter - Reply: Meteors in Australian Aboriginal Dreamings

    NASA Astrophysics Data System (ADS)

    Hamacher, Duane W.

    2011-06-01

    In response to the letter by Gorelli (2010) about Hamacher & Norris (2010), he is quite right about Aboriginal people witnessing impact events in Australia. There are several oral traditions regarding impact sites, some of which were probably witnessed, as Gorelli pointed out. The Henbury craters he mentions, with a young age of only ∼ 4200 years, have oral traditions that seem to describe a cosmic impact, including an aversion to drinking water that collects in the craters in fear that the fire-devil (which came from the sun, according to an Elder) would rain iron in them again. Other impact sites, such as Gosse's Bluff crater (Tnorala in the Arrernte language) and Wolfe Creek crater (Kandimalal in the Djaru language) have associated impact stories, despite their old ages (142 Ma and ∼0.3 Ma, respectively). In addition, many fireball and airburst events are described in Aboriginal oral traditions, a number of which seem to indicate impact events that are unknown to Western science. I have published a full treatise of meteorite falls and impact events in Australian Aboriginal culture that I would like to bring to the attention of Gorelli and WGN readers (Hamacher & Norris, 2009). Although our paper was published in the 2009 volume of Archaeoastronomy, it did not appear in print until just recently, which is probably why it has gone unnoticed. Recent papers describing the association between meteorites and Aboriginal cosmology (Hamacher, 2011) and comets in Aboriginal culture (Hamacher & Norris, 2011) have also been published, and would likely be of interest to WGN readers. I heartily agree with Gorelli that oral traditions are fast disappearing, taking with them a wealth of information about not only that peoples' culture, but also about past geologic and astronomical events, such as meteorite falls and cosmic impacts (a branch of the growing field of Geomythology). There is an old saying that "when a man dies, a library goes with him". This is certainly the

  6. Pit Crater

    NASA Image and Video Library

    2016-12-02

    This image captured by NASA 2001 Mars Odyssey spacecraft is located in Noachis Terra. The unnamed crater at the bottom of the image contains a central pit. Central features such as pits and peaks can provide information about both the impacted surface and the size of the meteorite. Orbit Number: 65680 Latitude: -28.4965 Longitude: 349.805 Instrument: VIS Captured: 2016-10-03 22:49 http://photojournal.jpl.nasa.gov/catalog/PIA21180

  7. Crater Moreux

    NASA Image and Video Library

    1998-06-08

    Color image of part of the Ismenius Lacus region of Mars (MC-5 quadrangle) containing the impact crater Moreux (right center); north toward top. The scene shows heavily cratered highlands in the south on relatively smooth lowland plains in the north separated by a belt of dissected terrain, containing flat-floored valleys, mesas, and buttes. This image is a composite of Viking medium-resolution images in black and white and low-resolution images in color. The image extends from latitude 36 degrees N. to 50 degrees N. and from longitude 310 degrees to 340 degrees; Lambert conformal conic projection. The dissected terrain along the highlands/lowlands boundary consists of the flat-floored valleys of Deuteronilus Mensae (on left) and Prontonilus Mensae (on right) and farther north the small, rounded hills of knobby terrain. Flows on the mensae floors contain striae that run parallel to valley walls; where valleys meet, the striae merge, similar to medial moraines on glaciers. Terraces within the valley hills have been interpreted as either layered rocks or wave terraces. The knobby terrain has been interpreted as remnants of the old, densely cratered highland terrain perhaps eroded by mass wasting. http://photojournal.jpl.nasa.gov/catalog/PIA00420

  8. A Bright Lunar Impact Flash Linked to the Virginid Meteor Complex

    NASA Technical Reports Server (NTRS)

    Moser, D. E.; Suggs, R. M.; Suggs, R. J.

    2015-01-01

    On 17 March 2013 at 03:50:54 UTC, NASA detected a bright impact flash on the Moon caused by a meteoroid impacting the lunar surface. There was meteor activity in Earth's atmosphere the same night from the Virginid Meteor Complex. The impact crater associated with the impact flash was found and imaged by Lunar Reconnaissance Orbiter (LRO). Goal: Monitor the Moon for impact flashes produced by meteoroids striking the lunar surface. Determine meteoroid flux in the 10's gram to kilogram size range.

  9. Dunes in a Crater Floor

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 6 August 2003

    This image shows the floor of a crater just north of the Argyre basin in the southern hemisphere. Dark dunes have been pushed up against the northeastern interior rim of the crater, indicating that the prevailing winds blow from the southwest.

    Image information: VIS instrument. Latitude -35.7, Longitude 324.1 East (35.9 West). 19 meter/pixel resolution.

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

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

  10. Regolith transport in craters on Eros

    NASA Astrophysics Data System (ADS)

    Mantz, A.; Sullivan, R.; Veverka, J.

    2004-01-01

    Images of Eros from the NEAR Shoemaker spacecraft reveal bright and dark albedo features on steep crater walls unlike markings previously observed on asteroids. These features have been attributed to the downslope movement of space-weathered regolith, exposing less weathered material (Science 292 (2001) 484; Meteor. Planet. Sci. 36 (2001) 1617; Icarus 155 (2002) 145). Here we present observations of the interiors of large craters (>1 km in diameter) to test this hypothesis and constrain the origin of the features. We find that bright regions in these craters correspond to steep slopes, consistent with previous work. The geographic distribution of craters with albedo variations shows no pattern and does not resemble the distribution of ponds, another phenomenon on Eros attributed to regolith movement. Shadows and other indications of topography are not observed at feature boundaries, implying that the transported layer is ⩽1 m thick. The presence of multiple bright and dark units on long slopes with sharp boundaries between them suggests that mobilized regolith may be halted by frictional or other effects before reaching the foot of the slope. Features on crater walls should darken at the same rate as bright ejecta deposits from crater formation; the lack of observed, morphologically fresh craters with bright interiors or ejecta suggests that the albedo patterns are younger than the most recently formed craters greater than about 100 m in diameter. Smaller or micrometeorite impacts, which would not necessarily leave evident deposits of bright ejecta, remain possible causes of albedo patterns. Although their effectiveness is difficult to assess, electrostatic processes and thermal creep are also candidates.

  11. Crater Floor Dune Field

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    Our final dune image shows a small dune field inside an unnamed crater south of Nili Fossae.

    Image information: VIS instrument. Latitude 20.6, Longitude 79 East (281 West). 19 meter/pixel resolution.

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

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

  12. Crater Dust Avalanches

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Dust avalanches, also called slope streaks, occur on many Martian terrains. The deposition of airborne dust on surfaces causes a bright tone in the THEMIS VIS images. Any movement of the dust downhill, a dust avalanche, will leave behind a streak where the darker, dust-free surface is exposed.

    These dust avalanches are located in a small canyon within a crater rim northeast of Naktong Vallis.

    Image information: VIS instrument. Latitude 7.1, Longitude 34.7 East (325.3 West). 17 meter/pixel resolution.

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

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

  13. Crater Dust Avalanches

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Dust avalanches, also called slope streaks, occur on many Martian terrains. The deposition of airborne dust on surfaces causes a bright tone in the THEMIS VIS images. Any movement of the dust downhill, a dust avalanche, will leave behind a streak where the darker, dust-free surface is exposed.

    This region of dust avalanches is located in and around a crater to the west of yesterday's image.

    Image information: VIS instrument. Latitude 14.7, Longitude 32.7 East (327.3 West). 18 meter/pixel resolution.

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

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

  14. Chipped Paint Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 9 April 2003

    In the high northern latitudes NW of Alba Patera, a smooth mantle of material that covers the landscape appears chipped away from the rim of a large crater. The prominent scarp that has formed from the retreat of the mantle lacks the rounded appearance of other ice-rich mantles found in the mid-latitudes. The nature of this mantling layer therefore is more enigmatic.

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

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

    Image information: VIS instrument. Latitude 62.9, Longitude 226.2 East (133.8 West). 19 meter/pixel resolution.

  15. Crater Dust Avalanches

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Dust avalanches, also called slope streaks, occur on many Martian terrains. The deposition of airborne dust on surfaces causes a bright tone in the THEMIS VIS images. Any movement of the dust downhill, a dust avalanche, will leave behind a streak where the darker, dust-free surface is exposed.

    These dust avalanches are located in a small canyon within a crater rim northeast of Naktong Vallis.

    Image information: VIS instrument. Latitude 7.1, Longitude 34.7 East (325.3 West). 17 meter/pixel resolution.

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

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

  16. Lava-Filled Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 12 June 2003

    Craters and hills form high standing streamlined plateaus or islands in a channeled area. The plateaus are rounded in the upstream direction and taper to a point in the downstream direction, indicating that the direction of flow in this area was roughly south to north, or bottom to top. The channels appear to be filled with lava flow deposits that are raised above the channel in some areas. A lava flow diverges around a small streamlined hill near the bottom of the image and then merges again around the northern end of it. Near the top of the image is a crater with a breach on the east (right) side that allowed the lava to flow in, leaving a lobate, high standing deposit. The channels may have been formed by the lava flows that currently fill them or there may have been flow of liquid water that created them before the lava was emplaced.

    Image information: VIS instrument. Latitude 16, Longitude 183 East (177 West). 19 meter/pixel resolution.

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

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

  17. Lava-Filled Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 12 June 2003

    Craters and hills form high standing streamlined plateaus or islands in a channeled area. The plateaus are rounded in the upstream direction and taper to a point in the downstream direction, indicating that the direction of flow in this area was roughly south to north, or bottom to top. The channels appear to be filled with lava flow deposits that are raised above the channel in some areas. A lava flow diverges around a small streamlined hill near the bottom of the image and then merges again around the northern end of it. Near the top of the image is a crater with a breach on the east (right) side that allowed the lava to flow in, leaving a lobate, high standing deposit. The channels may have been formed by the lava flows that currently fill them or there may have been flow of liquid water that created them before the lava was emplaced.

    Image information: VIS instrument. Latitude 16, Longitude 183 East (177 West). 19 meter/pixel resolution.

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

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

  18. Map showing the Elko crater field, Elko County, Nevada

    USGS Publications Warehouse

    Ketner, Keith B.; Roddy, David J.

    1980-01-01

    The Elko crater field consists of two arrays of rimmed craters in the valleys of Dorsey, Susie, and McClellan Creeks, 30 to 50 km north of Elko, Nevada. In the principal array, more the 165 craters are scattered irregularly in an area 3 km wide and 20 km long. Most of the the craters are circular but some, formed by overlap, are oval or irregular. They range from 5 m to 250 m in diameter and the relief of the largest ones, from the sedimentary floor of the cater to the top of the rim, is at least 6 m. The surficial material of the rims is principally gravel similar to that in the surrounding terrane. The surficial material inside the craters is primarily silt, probably blown in by the wind, and pebbles, apparently washed in from the rims. There is also a later of volcanic ash at a depth of about 2 m. This ash was identified by its physical and mineralogical composition as the Mazama ash (R. E. Wilcox, oral commun., 1976), a ±6600 year old ash bed also present in the alluvium of Dorsey and Susie Creeks. The craters are presently interpreted as having been formed by a meteor shower although no meteor material has been discovered. Investigation is continuing.

  19. Fresh Dark Ray Crater

    NASA Image and Video Library

    2011-10-15

    The crater on asteroid Vesta shown in this image from NASA Dawn spacecraft was emplaced onto the ejecta blanket of two large twin craters. Commonly, rays from impact craters are brighter than the surrounding surface.

  20. Central Peak Crater

    NASA Image and Video Library

    2010-10-07

    As crater size increases, craters become more complex. This moderate size crater contains a central peak, created by rebound of molten material just following the impact. This image was captured by NASA Mars Odyssey on Sept. 8, 2010.

  1. Venus - Impact Crater Isabella

    NASA Image and Video Library

    1996-11-26

    Crater Isabella is seen in this radar image from NASA Magellan spacecraft. The second largest impact crater on Venus, the crater is named in honor of the 15th Century queen of Spain, Isabella of Castile.

  2. Gusev Crater

    NASA Image and Video Library

    2003-03-13

    Images from NASA's Mars Odyssey spacecraft were used to create this mosaic of nighttime infrared images of Gusev Crater, which has been draped over topography data obtained by NASA Mars Global Surveyor. Variations in nighttime temperatures are due to differences in the abundance of rocky materials that retain their heat at night and stay relatively warm (bright). Fine grained dust and sand (dark) cools off more rapidly at night. This image mosaic covers an area approximately 180 kilometers (110 miles) on each side centered near 14 degrees S, 175 degrees E, looking toward the south in this simulated view. http://photojournal.jpl.nasa.gov/catalog/PIA04261

  3. Buried Craters

    NASA Technical Reports Server (NTRS)

    2005-01-01

    26 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows two circular features on the plains of northern Utopia. A common sight on the martian northern plains, these rings indicate the locations of buried impact craters.

    Location near: 65.1oN, 261.2oW Image width: 2 km (1.2 mi) Illumination from: lower left Season: Northern Summer

  4. Database of Properties of Meteors

    NASA Technical Reports Server (NTRS)

    Suggs, Rob; Anthea, Coster

    2006-01-01

    A database of properties of meteors, and software that provides access to the database, are being developed as a contribution to continuing efforts to model the characteristics of meteors with increasing accuracy. Such modeling is necessary for evaluation of the risk of penetration of spacecraft by meteors. For each meteor in the database, the record will include an identification, date and time, radiant properties, ballistic coefficient, radar cross section, size, density, and orbital elements. The property of primary interest in the present case is density, and one of the primary goals in this case is to derive densities of meteors from their atmospheric decelerations. The database and software are expected to be valid anywhere in the solar system. The database will incorporate new data plus results of meteoroid analyses that, heretofore, have not been readily available to the aerospace community. Taken together, the database and software constitute a model that is expected to provide improved estimates of densities and to result in improved risk analyses for interplanetary spacecraft. It is planned to distribute the database and software on a compact disk.

  5. A Crater Split In Two

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 23 September 2003

    A 22 km-diameter crater has been sliced by the tectonic forces that produced the rift known as Sirenum Fossae. The orientation of this rift is roughly radial to the great Tharsis volcano Arsia Mons, probably indicating a link between the formation of the rift and the volcano. Note how the rift cuts through a jumble of mounds on the floor of the crater. This indicates a sequence of events beginning with the formation of the crater followed by an infilling of material that was then eroded into the mounds and ultimately split open by the shifting martian crust.

    Image information: VIS instrument. Latitude -29.7, Longitude 211.7 East (148.3 West). 19 meter/pixel resolution.

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

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

  6. Concentric Crater Floor Deposits in Daedalia Planum

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 3 September 2003

    Concentric crater floor deposits in Daedalia Planum. Lava flows appear to be converging on this crater from the northeast as well as on the crater floor. The concentric floor deposits may be the result of exposed and eroded layers of sediment that make up the crater floor.

    Image information: VIS instrument. Latitude -22.3, Longitude 221.5 East (138.5 West). 19 meter/pixel resolution.

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

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

  7. Signs of Landscape Modifications at Martian Crater

    NASA Technical Reports Server (NTRS)

    2009-01-01

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

    The lower portion of this image from the Thermal Emission Imaging System camera (THEMIS) on NASA's Mars Odyssey orbiter shows a crater about 16 kilometers (10 miles) in diameter with features studied as evidence of deposition or erosion. The crater is centered at 40.32 degrees south latitude and 132.5 degrees east longitude, in the eastern portion of the Hellas basin on Mars. It has gullies and arcuate ridges on its north, pole-facing interior wall. This crater is in the center of a larger (60-kilometer or 37-mile diameter) crater with lobate flows on its north, interior wall. The image, number V07798008 in the THEMIS catalog, covers a swath of ground 17.4 kilometers (10.8 miles) wide.

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

  8. A fast meteor detection algorithm

    NASA Astrophysics Data System (ADS)

    Gural, P.

    2016-01-01

    A low latency meteor detection algorithm for use with fast steering mirrors had been previously developed to track and telescopically follow meteors in real-time (Gural, 2007). It has been rewritten as a generic clustering and tracking software module for meteor detection that meets both the demanding throughput requirements of a Raspberry Pi while also maintaining a high probability of detection. The software interface is generalized to work with various forms of front-end video pre-processing approaches and provides a rich product set of parameterized line detection metrics. Discussion will include the Maximum Temporal Pixel (MTP) compression technique as a fast thresholding option for feeding the detection module, the detection algorithm trade for maximum processing throughput, details on the clustering and tracking methodology, processing products, performance metrics, and a general interface description.

  9. Spectroscopic Analysis of Geminid Meteors

    NASA Astrophysics Data System (ADS)

    Borovicka, J.

    2010-12-01

    I have analyzed 89 spectra of Geminid meteors obtained with image intensified video cameras in 1997-2004. Details of observation techniques and spectra analysis are given. Intensities of lines of Mg, Na, and Fe have been studied. Both Fe and Na lines were found to be fainter relatively to Mg than expected for chondritic composition. Moreover, the Na line intensity varied strongly from meteor to meteor. Based on the low Fe/Mg ratio, similar to other cometary meteoroids, I argue that 3200 Phaethon, the parent body of Geminids, is of cometary origin. Severe loss of Na occurred due to solar heating at the low perihelion distance of 0.14 AU. Varying meteoroid age seems to be the most plausible explanation of varying Na content from meteoroid to meteoroid, although other explanations, such as meteoroid origin in different depths in Phaethon or internal Phaethon inhomogeneities, are possible as well.

  10. Maunder Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 24 May 2002) The Science This image is of a portion of Maunder Crater located at about 49 S and 358 W (2 E). There are a number of interesting features in this image. The lower left portion of the image shows a series of barchan dunes that are traveling from right to left. The sand does not always form dunes as can be seen in the dark and diffuse areas surrounding the dune field. The other interesting item in this image are the gullies that can be seen streaming down from just beneath a number of sharp ridgelines in the upper portion of the image. These gullies were first seen by the MOC camera on the MGS spacecraft and it is though that they formed by groundwater leaking out of the rock layers on the walls of craters. The water runs down the slope and forms the fluvial features seen in the image. Other researchers think that these features could be formed by other fluids, such as CO2. These features are typically seen on south facing slopes in the southern hemisphere, though this image has gullies on north facing slopes as well. The Story Little black squigglies seem to worm their way down the left-hand side of this image. These land features are called barchan (crescent-shaped) dunes. Barchan dunes are found in sandy deserts on Earth, so it's no surprise the Martian wind makes them a common site on the red planet too. They were first named by a Russian scientist named Alexander von Middendorf, who studied the inland desert dunes of Turkistan. The barchan dunes in this image occur in the basin of Maunder crater on Mars, and are traveling from right to left. The sand does not always form dunes, though, as can be seen in the dark areas of scattered sand surrounding the dune field. Look for the streaming gullies that appear just beneath a number of sharp ridgelines in the upper portion of the image. These gullies were first discovered by the Mars Orbital Camera on the Mars Global Surveyor spacecraft. While most crater gullies are found on south

  11. Maunder Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 24 May 2002) The Science This image is of a portion of Maunder Crater located at about 49 S and 358 W (2 E). There are a number of interesting features in this image. The lower left portion of the image shows a series of barchan dunes that are traveling from right to left. The sand does not always form dunes as can be seen in the dark and diffuse areas surrounding the dune field. The other interesting item in this image are the gullies that can be seen streaming down from just beneath a number of sharp ridgelines in the upper portion of the image. These gullies were first seen by the MOC camera on the MGS spacecraft and it is though that they formed by groundwater leaking out of the rock layers on the walls of craters. The water runs down the slope and forms the fluvial features seen in the image. Other researchers think that these features could be formed by other fluids, such as CO2. These features are typically seen on south facing slopes in the southern hemisphere, though this image has gullies on north facing slopes as well. The Story Little black squigglies seem to worm their way down the left-hand side of this image. These land features are called barchan (crescent-shaped) dunes. Barchan dunes are found in sandy deserts on Earth, so it's no surprise the Martian wind makes them a common site on the red planet too. They were first named by a Russian scientist named Alexander von Middendorf, who studied the inland desert dunes of Turkistan. The barchan dunes in this image occur in the basin of Maunder crater on Mars, and are traveling from right to left. The sand does not always form dunes, though, as can be seen in the dark areas of scattered sand surrounding the dune field. Look for the streaming gullies that appear just beneath a number of sharp ridgelines in the upper portion of the image. These gullies were first discovered by the Mars Orbital Camera on the Mars Global Surveyor spacecraft. While most crater gullies are found on south

  12. Meteor Shower Identification and Characterization with Python

    NASA Technical Reports Server (NTRS)

    Moorhead, Althea

    2015-01-01

    The short development time associated with Python and the number of astronomical packages available have led to increased usage within NASA. The Meteoroid Environment Office in particular uses the Python language for a number of applications, including daily meteor shower activity reporting, searches for potential parent bodies of meteor showers, and short dynamical simulations. We present our development of a meteor shower identification code that identifies statistically significant groups of meteors on similar orbits. This code overcomes several challenging characteristics of meteor showers such as drastic differences in uncertainties between meteors and between the orbital elements of a single meteor, and the variation of shower characteristics such as duration with age or planetary perturbations. This code has been proven to successfully and quickly identify unusual meteor activity such as the 2014 kappa Cygnid outburst. We present our algorithm along with these successes and discuss our plans for further code development.

  13. The making of meteor astronomy: part V.

    NASA Astrophysics Data System (ADS)

    Beech, M.

    1993-12-01

    The first true comparisons between the observations and the "rising vapors" hypothesis of meteor origins were made in the early eighteenth century. One of the key figures in the new meteoric dialogue was Edmond Halley.

  14. Global Variation of Meteor Trail Plasma Turbulence

    NASA Technical Reports Server (NTRS)

    Dyrud, L. P.; Hinrichs, J.; Urbina, J.

    2011-01-01

    We present the first global simulations on the occurrence of meteor trail plasma irregularities. These results seek to answer the following questions: when a meteoroid disintegrates in the atmosphere will the resulting trail become plasma turbulent, what are the factors influencing the development of turbulence, and how do they vary on a global scale. Understanding meteor trail plasma turbulence is important because turbulent meteor trails are visible as non-specular trails to coherent radars, and turbulence influences the evolution of specular radar meteor trails, particularly regarding the inference of mesospheric temperatures from trail diffusion rates, and their usage for meteor burst communication. We provide evidence of the significant effect that neutral atmospheric winds and density, and ionospheric plasma density have on the variability of meteor trail evolution and the observation of nonspecular meteor trails, and demonstrate that trails are far less likely to become and remain turbulent in daylight, explaining several observational trends using non-specular and specular meteor trails.

  15. Wake in faint television meteors

    NASA Technical Reports Server (NTRS)

    Robertson, M. C.; Hawkes, Robert L.

    1992-01-01

    The two component dustball model was used in numerical lag computation. Detached grain lag is typically less than 2 km, with expected wakes of a few hundred meters. True wake in television meteors is masked by apparent wake due to the combined effects of image persistence and blooming. To partially circumvent this problem, we modified a dual MCP intensified CID video system by addition of a rotating shutter to reduce the effective exposure time to about 2.0 ms. Preliminary observations showed that only 2 of 27 analyzed meteors displayed statistically significant wake.

  16. Leonid meteors, 2001 November 18

    NASA Astrophysics Data System (ADS)

    McGee, H. W.; Mobberley, M. P.

    2002-02-01

    Leonid meteors photographed from Palau, Micronesia, on 2001 November 18. Clockwise from top right: 3 meteors in Corvus, 19.18-19.20 UT; brilliant fireball in Orion, 18.48.30 UT; bright Leonid in Hydra, 19.06 UT. 50mm f/1.8 lens, 1600 ISO Fuji Superia film; M.P. Mobberley. Top left: Composite of three 5-minute exposures between 19.15 and 19.36 UT. 28mm f2.8 lens, 800 ISO Kodak Gold film; H.W. McGee.

  17. A Bright Lunar Impact Flash Linked to the Virginid Meteor Complex

    NASA Technical Reports Server (NTRS)

    Moser, D. E.; Suggs, R. M.; Suggs, R. J.

    2015-01-01

    Since early 2006, NASA's Marshall Space Flight Center (MSFC) has observed over 330 impact flashes on the Moon, produced by meteoroids striking the lunar surface. On 17 March 2013 at 03:50:54.312 UTC, the brightest flash of a 9-year routine observing campaign was observed by two 0.35 m telescopes at MSFC. The camera onboard the Lunar Reconnaissance Orbiter (LRO), a NASA spacecraft mapping the Moon from lunar orbit, discovered the fresh crater associated with this impact [1] approximately 3 km from the location predicted by a newly developed geolocation technique [2]. The meteoroid impactor responsible for this event may have been part of a stream of large particles encountered by the Earth/Moon associated with the Virginid Meteor Complex, as evidenced by a cluster of five fireballs seen in Earth's atmosphere on the same night by the NASA All Sky Fireball Network [3] and the Southern Ontario Meteor Network [4]. Crater size calculations based on assumptions derived from fireball measurements yielded an estimated crater diameter of 10-23 m rim-to-rim using the Holsapple [5] and Gault [6] models, a result consistent with the observed crater measured to be 18 m across. This is the first time a lunar impact flash has been associated with fireballs in Earth's atmosphere and an observed crater.

  18. Note on the 1972 Giacobinid meteor shower.

    NASA Technical Reports Server (NTRS)

    Harvey, G. A.

    1973-01-01

    It is shown that the 1972 Giacobinid meteor shower was extremely weak with a peak activity of two to three visual meteors per hour. Only two meteor spectra were obtained from the 17 slitless spectrograph systems operated by the Langley Research Center. The largely unexpected, essentially null results of the 1972 Giacobinid meteor shower observations are indicative of the present limited understanding and predictability of cosmic dust storms.

  19. The new July meteor shower

    NASA Astrophysics Data System (ADS)

    Zoladek, Przemyslaw; Wisniewski, Mariusz

    2012-12-01

    A new meteor stream was found after an activity outburst observed on 2005 July 15. The radiant was located five degrees west of the possible early Perseid radiant, close to the star Zeta Cassiopeiae. Numerous bright meteors and fireballs were observed during this maximum. Analysis of the IMO Video Database and the SonotaCo orbital database revealed an annual stream which is active just before the appearance of the first Perseids, with a clearly visible maximum at solar longitude 113°1. Activity of the stream was estimated as two times higher than activity of the Alpha Capricornids at the same time. The activity period extends from July 12 to 17, during maximum the radiant is visible at coordinates alpha = 5°9, delta = +50°5, and observed meteors are fast, with Vg = 57.4 km/s. The shower was reported to the IAU Meteor Data Center and recognized as a new discovery. According to IAU nomenclature the new stream should be named the Zeta Cassiopeiids (ZCS). %z Arlt R. (1992). WGN, Journal of the IMO, 20:2, 62-69. Drummond J. D. (1981). Icarus, 45, 545-553. Kiraga M. and Olech A. (2001). In Arlt R., Triglav M., and Trayner C., editors, Proceedings of the International Meteor Conference, Pucioasa, Romania, 21-24 September 2000, pages 45-51. IMO. Molau S. (2007). In Bettonvil F. and Kac J., editors, Proceedings of the International Meteor Conference, Roden, The Netherlands, 14-17 September 2006, pages 38-55. IMO. Molau S. and Rendtel J. (2009). WGN, Journal of the IMO, 37:4, 98-121. Olech A., Zoladek P., Wisniewski M., Krasnowski M., Kwinta M., Fajfer T., Fietkiewicz K., Dorosz D., Kowalski L., Olejnik J., Mularczyk K., and Zloczewski K. (2006). In Bastiaens L., Verbert J., Wislez J.-M., and Verbeeck C., editors, Proceedings of the International Meteor Conference, Oostmalle, Belgium, 15-18 September 2005, pages 53-62. IMO. Poleski R. and Szaruga K. (2006). In Bastiaens L., Verbert J., Wislez J.-M., and Verbeeck C., editors, Proceedings of the International Meteor

  20. New trends in meteor radio receivers

    NASA Astrophysics Data System (ADS)

    Rault, Jean-Louis

    2014-01-01

    Recent progresses in low cost—but performing—SDR (software defined radio) technology presents a major breakthrough in the domain of meteor radio observations. Their performances are now good enough for meteor work and should therefore encourage newcomers to join the meteor radio community.

  1. Croatian Meteor Network: Ongoing work 2015 - 2016

    NASA Astrophysics Data System (ADS)

    Šegon, D.; Vida, D.; Korlević, K.; Andreić, Ž.

    2016-01-01

    Ongoing work of the Croatian Meteor Network (CMN) between the 2015 and 2016 International Meteor Conferences is presented. The current sky coverage is considered, software updates and updates of orbit catalogues are described. Furthermore, the work done on meteor shower searches, international collaborations as well as new fields of research are discussed. Finally, the educational efforts made by the CMN are described.

  2. Review of the advances in meteor studies

    NASA Astrophysics Data System (ADS)

    Borovička, J.

    2014-07-01

    I will present a personal conference summary in the field of meteor studies. The most important advances concerning meteors since the last ACM conference (2012 in Japan) will be highlighted. The most interesting event, which occurred in between and was discussed also on this conference, was the Chelyabinsk superbolide. Nevertheless, progress was made also in other meteor studies.

  3. A Crater on a Crater Wall

    NASA Image and Video Library

    2017-06-13

    It's not that common to see craters on steep hills, partly because rocks falling downhill can quickly erase such craters. Here, however, NASA's Mars Reconnaissance Orbiter (MRO) observes a small impact has occurred on the sloping wall of a larger crater and is well-preserved. Dark, blocky ejecta from the smaller crater has flowed downhill (to the west) toward the floor of the larger crater. Understanding the emplacement of such ejecta on steep hills is an area of ongoing research. https://photojournal.jpl.nasa.gov/catalog/PIA21758

  4. Meteor Beliefs Project: Meteors in the Maori astronomical traditions of New Zealand

    NASA Astrophysics Data System (ADS)

    Britton, Tui R.; Hamacher, Duane W.

    2014-02-01

    We review the literature for perceptions of meteors in the Maori culture of Aotearoa or New Zealand. We examine representations of meteors in religion, story, and ceremony. We find that meteors are sometimes personified as gods or children, or are seen as omens of death and destruction. The stories we found highlight the broad perception of meteors found throughout the Maori culture, and note that some early scholars conflated the terms comet and meteor.

  5. Meteor detections using the LWA

    NASA Astrophysics Data System (ADS)

    Obenberger, K.; Taylor, G. B.; Holmes, J. M.

    2016-12-01

    Using the all-sky imaging capability of the LWA1 radio telescope, we have discovered hundreds of radio pulses lasting 5 - 300 seconds at frequencies between 20 and 50 MHz. These pluses are associated with meteors and are thought to be radio afterglows that are occasionally emitted from meteor trails. With wideband measurements from 4 events, we now know the spectra is broad, following a steep inverse power law. The range in frequencies follows the range of plasma frequencies expected within turbulent trails of large meteors, suggesting a plasma emission process. Furthermore, a recent optical/radio campaign has shown that radio afterglows are either severely suppressed or do not exist below a cutoff of 90 km. This finding agrees with the plasma wave emission hypothesis where electron collisions would damp low altitude wave generation. Finally, using both the LWA1 and a newly construction LWA station 75 km away, we are now observing the same radio afterglows from multiple perspectives. This allows for night and day triangulation of radio afterglows, and possibly even long baseline interferometry, a powerful technique that could be used to probe the structure and dynamics of meteor trails and the surrounding ionosphere.

  6. Chasing Meteors With a Microscope.

    ERIC Educational Resources Information Center

    Jones, Richard C.

    1993-01-01

    Describes types of meteors and micrometeorites that enter the Earth's atmosphere. Presents an activity where students collect micrometeorites with a strip of tape in an undisturbed outdoor area. After 24 hours, they examine the tape by sandwiching it between 2 glass slides and view through a microscope at 100X. (PR)

  7. Chasing Meteors With a Microscope.

    ERIC Educational Resources Information Center

    Jones, Richard C.

    1993-01-01

    Describes types of meteors and micrometeorites that enter the Earth's atmosphere. Presents an activity where students collect micrometeorites with a strip of tape in an undisturbed outdoor area. After 24 hours, they examine the tape by sandwiching it between 2 glass slides and view through a microscope at 100X. (PR)

  8. Meteors Without Borders: a global campaign

    NASA Astrophysics Data System (ADS)

    Heenatigala, T.

    2012-01-01

    "Meteors Without Borders" is a global project, organized by Astronomers Without Borders and launched during the Global Astronomy Month in 2010 for the Lyrid meteor shower. The project focused on encouraging amateur astronomy groups to hold public outreach events for major meteor showers, conduct meteor-related classroom activities, photography, poetry and art work. It also uses social-media platforms to connect groups around the world to share their observations and photography, live during the events. At the International Meteor Conference 2011, the progress of the project was presented along with an extended invitation for collaborations for further improvements of the project.

  9. Physical and dynamical studies of meteors

    NASA Technical Reports Server (NTRS)

    Southworth, R. B.; Sekanina, Z.

    1973-01-01

    Interplanetary distributions from a sample of 20,000 radar meteor observations are presented. These distributions are freed from all known selection effects with the exception of a possible bias against fragmenting meteors which has not yet been adequately assessed. These data thus represent the largest and most accurate collection of radar meteor distributions. Both general average distribution and the distribution of meteor streams with their comet and asteroid associations are presented. Sporadic space density and space density of meteor streams are also included.

  10. Four years of meteor spectra patrol

    NASA Technical Reports Server (NTRS)

    Harvey, G. A.

    1974-01-01

    The development of the NASA-Langley Research Center meteor spectra patrol is described in general terms. The recording of very faint meteors was made possible by three great strides in optical and photographic technology in the 1960's: (1) the availability of optical-grade fused silica at modest cost, (2) the development of large transmission gratings with high blaze efficiency, and (3) the development of a method for avoiding plate fogging due to background skylight, which consisted of using a photoelectric meteor detector which actuates the spectrograph shutter when a meteor occurs in the field. The classification scheme for meteor spectra developed by Peter M. Millman is described.

  11. Arizona Copper

    NASA Image and Video Library

    2017-09-27

    Arizona produces 60% of the total copper mined in the US; in 2007, 750,000 tons of copper came out of the state. One of the major mining districts is located about 30 km south of Tucson. Starting around 1950, open-pit mining replaced underground operations, and the ASARCO-Mission complex, Twin Buttes, and Sierrita mines became large open pit operations. Accompanying copper mineralization, silver, molybdenum, zinc, lead and gold are extracted. In addition to the pits themselves, enormous leach ponds and tailings piles surround the pits. The image was acquired May 31, 2012, covers an area of 22 by 28 km, and is located at 31.9 degrees north, 111 degrees west. With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on Terra. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate, Washington, D.C. More information about ASTER is available at asterweb.jpl.nasa.gov/ Credit: NASA

  12. Structure of the Chesapeake Bay Impact Crater from Wide-Angle Seismic Waveform Tomography

    NASA Astrophysics Data System (ADS)

    Lester, W. R.; Hole, J. A.; Catchings, R. D.; Bleibinhaus, F.

    2006-12-01

    The 35 million year old Chesapeake Bay impact structure is one of the largest and most well preserved meteor/comet impact structures on Earth. As a marine impact on a continental shelf, its morphology consists of a deep inner crater penetrating pre-existing crystalline basement surrounded by a much wider, shallower crater within the overlying sediments. In 2004, the U.S. Geological Survey conducted a combined refraction and low-fold reflection seismic survey across the northern part of the inner crater with the goals of constraining crater structure and identifying an ideal drill site for a deep borehole. Waveform inversion was applied to the seismic data to produce a high-resolution seismic velocity model of the inner crater. This significantly improved the spatial resolution over previous images based on travel times. Under the northeastern part of the outer crater, eastward-sloping, relatively intact crystalline basement is at a depth of ~1.5 km. The edge of the inner crater is at ~17 km radius and slopes gradually inward to penetrate pre-existing crystalline basement. The top of crystalline rock on the central uplift is about 0.8 km higher than its surroundings. Seismic velocity of crystalline rocks under the inner crater is much lower than under the outer crater, suggesting strong fracturing/brecciation of the inner crater floor and even stronger brecciation of the central uplift. A basement uplift and lateral change of basement velocity occurs at a radius of ~12 km and is interpreted as possibly indicating the edge of the transient crater caused by impact excavation prior to collapse. Assuming a 24 km diameter transient crater, scaling laws based on extraterrestrial craters and numerical models predict the observed inner crater diameter, central uplift diameter, and inner crater depth. This suggests that the crater collapse processes that created the inner crater in crystalline rocks were unaffected by the much weaker rheology of the overlying sediments.

  13. Determination of the meteor limiting magnitude

    NASA Astrophysics Data System (ADS)

    Kingery, A.; Blaauw, R. C.

    2017-09-01

    We present our method to calculate the meteor limiting magnitude. The limiting meteor magnitude defines the faintest magnitude at which all meteors are still detected by a given system. An accurate measurement of the limiting magnitude is important in order to calculate the meteoroid flux from a meteor shower or sporadic source. Since meteor brightness is linked to meteor mass, the limiting magnitude is needed to calculate the limiting mass of the meteor flux measurement. The mass distribution of meteoroids is thought to follow a power law, thus being slightly off in the limiting magnitude can have a significant effect on the measured flux. Sky conditions can change on fairly short timescales; therefore one must monitor the meteor limiting magnitude at regular intervals throughout the night, rather than just measuring it once. We use the stellar limiting magnitude as a proxy of the meteor limiting magnitude. Our method for determining the stellar limiting magnitude and how we transform it into the meteor limiting magnitude is presented. These methods are currently applied to NASA's wide-field meteor camera network to determine nightly fluxes, but are applicable to other camera networks.

  14. Recent Advances in Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Meachem, Terry; Cooke, William J.

    2003-01-01

    One of the most common (and obvious) problems with video meteor data involves the saturation of the output signal produced by bright meteors, resulting in the elimination of such meteors from photometric determinations. It is important to realize that a "bright" meteor recorded by intensified meteor camera is not what would be considered "bright" by a visual observer - indeed, many Generation II or III camera systems are saturated by meteors with a visual magnitude of 3, barely even noticeable to the untrained eye. As the relatively small fields of view (approx.30 ) of the camera systems captures at best modest numbers of meteors, even during storm peaks, the loss of meteors brighter than +3 renders the determination of shower population indices from video observations even more difficult. Considerable effort has been devoted by the authors to the study of the meteor camera systems employed during the Marshall Space Flight Center s Leonid ground-based campaigns, and a calibration scheme has been devised which can extend the useful dynamic range of such systems by approximately 4 magnitudes. The calibration setup involves only simple equipment, available to amateur and professional, and it is hoped that use of this technique will make for better meteor photometry, and move video meteor analysis beyond the realm of simple counts.

  15. Recent Advances in Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Meachem, Terry; Cooke, William J.

    2003-01-01

    One of the most common (and obvious) problems with video meteor data involves the saturation of the output signal produced by bright meteors, resulting in the elimination of such meteors from photometric determinations. It is important to realize that a "bright" meteor recorded by intensified meteor camera is not what would be considered "bright" by a visual observer - indeed, many Generation II or III camera systems are saturated by meteors with a visual magnitude of 3, barely even noticeable to the untrained eye. As the relatively small fields of view (approx.30 ) of the camera systems captures at best modest numbers of meteors, even during storm peaks, the loss of meteors brighter than +3 renders the determination of shower population indices from video observations even more difficult. Considerable effort has been devoted by the authors to the study of the meteor camera systems employed during the Marshall Space Flight Center s Leonid ground-based campaigns, and a calibration scheme has been devised which can extend the useful dynamic range of such systems by approximately 4 magnitudes. The calibration setup involves only simple equipment, available to amateur and professional, and it is hoped that use of this technique will make for better meteor photometry, and move video meteor analysis beyond the realm of simple counts.

  16. Determination of the Meteor Limiting Magnitude

    NASA Technical Reports Server (NTRS)

    Kingery, A.; Blaauw, R.; Cooke, W. J.

    2016-01-01

    The limiting meteor magnitude of a meteor camera system will depend on the camera hardware and software, sky conditions, and the location of the meteor radiant. Some of these factors are constants for a given meteor camera system, but many change between meteor shower or sporadic source and on both long and short timescales. Since the limiting meteor magnitude ultimately gets used to calculate the limiting meteor mass for a given data set, it is important to have an understanding of these factors and to monitor how they change throughout the night, as a 0.5 magnitude uncertainty in limiting magnitude translates to a uncertainty in limiting mass by a factor of two.

  17. Meteor light curves: the relevant parameters

    NASA Astrophysics Data System (ADS)

    Brosch, N.; Helled, Ravit; Polishook, D.; Almoznino, E.; David, N.

    2004-11-01

    We investigate a uniform sample of 113 light curves of meteors collected at the Wise Observatory in 2002 November during a campaign to observe the Leonid meteor shower. We use previously defined descriptors, such as the classical skewness parameter F and a recently defined pointedness variable P, along with a number of other measurable or derived quantities, in order to explore the parameter space in search of meaningful light curve descriptors. In comparison with previous publications, we make extensive use of statistical techniques to reveal links among the various parameters and to understand their relative importance. In particular, we show that meteors with long-duration trails rise slowly to their maximal brightness and also decay slowly from the peak, while showing milder flaring than other meteors. Early skewed meteors, with their peak brightness in the first half of the light curve, show a fast rise to the peak. We show that the duration of the luminous phase of the meteor is the most important variable differentiating among the 2002 meteor trails. The skewness parameter F, which is widely used in meteor light curve analyses, appears only as the second or third in order of importance in explaining the variance among the observed light curves, with the most important parameter being related to the duration of the meteor light-producing phase. We suggest that the pointedness parameter P could possibly be useful in describing differences among meteor showers, perhaps by being related to the different compositions of meteoroids, and also in comparing observations to model light curves. We compare the derived characteristics of the 2002 meteors with model predictions and conclude that more work is required to define a consistent set of measurable and derived light-curve parameters that would characterize the light production from meteors. We suggest that meteor observers should consider publishing more characterizing parameters from the light curves they

  18. Extraterrestrial meteors: a martian meteor and its parent comet.

    PubMed

    Selsis, Franck; Lemmon, Mark T; Vaubaillon, Jérémie; Bell, James F

    2005-06-02

    Regular meteor showers occur when a planet approaches the orbit of a periodic comet--for example, the Leonid shower is evident around 17 November every year as Earth skims past the dusty trail of comet Tempel-Tuttle. Such showers are expected to occur on Mars as well, and on 7 March last year, the panoramic camera of Spirit, the Mars Exploration Rover, revealed a curious streak across the martian sky. Here we show that the timing and orientation of this streak, and the shape of its light curve, are consistent with the existence of a regular meteor shower associated with the comet Wiseman-Skiff, which could be characterized as martian Cepheids.

  19. Small Impact Craters with Dark Ejecta Deposits

    NASA Technical Reports Server (NTRS)

    1999-01-01

    When a meteor impacts a planetary surface, it creates a blast very much like a bomb explosion. Shown here are two excellent examples of small impact craters on the martian surface. Each has a dark-toned deposit of material that was blown out of the crater (that is, ejected) during the impact. Materials comprising these deposits are called ejecta. The ejecta here is darker than the surrounding substrate because each crater-forming blast broke through the upper, brighter surface material and penetrated to a layer of darker material beneath. This darker material was then blown out onto the surface in the radial pattern seen here.

    The fact that impact craters can penetrate and expose material from beneath the upper surface of a planet is very useful for geologists trying to determine the nature and composition of the martian subsurface. The scene shown here is illuminated from the upper left and covers an area 1.1 km (0.7 mi) wide by 1.4 km (0.9 mi). The larger crater has a diameter of about 89 meters (97 yards), the smaller crater is about 36 meters (39 yards) across. The picture is located in Terra Meridiani and was taken by the Mars Global Surveyor Mars Orbiter Camera.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  20. Venus - Transitional Crater

    NASA Image and Video Library

    1996-10-23

    During orbits 423 through 424 on 22 September 1990, NASA's Magellan imaged this impact crater that is located at latitude 10.7 degrees north and longitude 340.7 degrees east. This crater is shown as a representative of Venusian craters that are of the proper diameter (about 15 kilometers) to be 'transitional' in their morphology between 'complex' and irregular' craters. Complex craters account for about 96 percent of all craters on Venus with diameters larger than about 15 kilometers; they are thought to have been formed by the impact of a large, more or less intact, mass of asteroidal material that has not been excessively effected during its passage through the dense Venusian atmosphere. Complex craters are characterized by circular rims, terraced inner wall slopes, well developed ejecta deposits, and flat floors with a central peak or peak ring. Irregular craters make up about 60 percent of the craters with diameters less than about 15 kilometers. Irregular craters are thought to form as the result of the impact of asteroidal projectiles that have been aerodynamically crushed and fragmented during their passage through the atmosphere. Irregular craters are characterized by irregular and/or discontinuous rims and hummocky or multiple floors. The 'transitional' crater shown here has a somewhat circular rim like larger complex craters, but has the hummocky floor and asymmetric ejecta characteristic of smaller irregular craters. http://photojournal.jpl.nasa.gov/catalog/PIA00468

  1. Meteor observations under the INASAN supervision

    NASA Astrophysics Data System (ADS)

    Kartashova, A. P.; Bagrov, A. V.

    2012-09-01

    Meteor observations have the specific property: we do not know in advance neither area on the celestial sphere, not the time when the event occurs. Besides that, a meteor flash in the atmosphere has duration few seconds or less, and it is hard problem to gather enough photons from it to register a faint or fast meteor. There are a number of tasks in meteor astronomy for solution of which not only a simple registration of meteors in the optical range is required, but a high spatial and time resolution as well. Television method is the most acceptable for such a case and is widely used in the practice of meteor observations. Television meteor observations in Russia are carried out under the Institute of Astronomy of the Russian Academy of Sciences (INASAN) supervision in different regions of Russia: Moscow region, Irkutsk, Ryazan and North Caucasus. The TV system PatrolCa designed for observations in the wide field of view (the ordinary for most of meteor cameras), consists of the following components: the high resolution cameras Watec LCL-902HS, the wide-angle photograph objectives Canon 6/0.8 (F=6 mm, the aperture 1:0.8). The cameras have fields of view of 50°x40° and have a limiting magnitude (for meteors) of +4 m ÷ +5 m. The FAVOR (FAst Variability Optical Registrator) camera is used for observations of faint meteors at the North Caucasus [1]. The basic components of this camera are the following: the high-aperture lense objective with the aperture 150 mm and the focal length 180mm (the aperture 1:1.2), the image intensifier, the objective reversal, CCD receiver "Videoscan" VS-СTT285 2001. The CCD "Sony" ICX285 has format 1380 х 1024 pixels. The camera has a field of view of 18 ° х 20°, and has a limiting magnitude of above +10m (for meteors). The two cameras similar to FAVOR (named SMAC) were designed for double-station observations of faint meteors. The results of observations at these cameras are presented. The observations were held by both methods

  2. Artificial meteor ablation studies: Olivine

    NASA Technical Reports Server (NTRS)

    Blanchard, M. B.; Cunningham, G. G.

    1973-01-01

    Artificial meteor ablation was performed on a Mg-rich olivine sample using an arc-heated plasma of ionized air. Experimental conditions simulated a meteor traveling about 12 km/sec at an altitude of 70 km. The mineral content of the original olivine sample was 98% olivine (including traces of olivine alteration products) and 2% chromite. Forsterite content of the original olivine was Fo-89. After ablation, the forsterite content had increased to Fo-94 in the recrystallized olivine. In addition, lamella-like intergrowths of magnetite were prevalent constituents. Wherever magnetite occurred, there was an increase in Mg and a corresponding decrease in Fe for the recrystallized olivine. The Allende fusion crust consisted of a recrystallized olivine, which was more Mg-rich and Fe-deficient than the original meteorite's olivine, and abundant magnetite grains. Although troilite and pentlandite were the common opaque mineral constituents in this meteorite, magnetite was the principal opaque mineral found in the fusion crust.

  3. The ALTAIR Meteor Measurements Program

    NASA Technical Reports Server (NTRS)

    Cooke, William J.

    2007-01-01

    Established in late 2006, the Meteor Measurements Program is in the process of using the ALTAIR radar located on Kwajelein Atoll to obtain radar observations of sporadic and shower meteoroids. The goals are to determine meteoroid masses, orbits, ballistic coefficients and densities, which shall be provided to the Meteoroid Environment Office (MEO) at Marshall Space Flight Center. These data and analyses shall then be used by the MEO to 1) Add a realistic density distribution to the new Meteoroid Engineering Model (MEM), which is the specified environment for vehicle design in the NASA Constellation (return to Moon) program. This program is the implementation of President Bush's Vision for Space Exploration (VSE). 2) Investigate the meteoroid velocity distribution at smaller masses. 3) Strive to understand the differences (biases) in meteoroid observations produced by systems like ALTAIR and those of the meteor patrol radars, such as the University of Western Ontario's CMOR system. This paper outlines the program details and its progress.

  4. The ALTAIR Meteor Measurements Program

    NASA Technical Reports Server (NTRS)

    Cooke, William J.

    2007-01-01

    Established in late 2006, the Meteor Measurements Program is in the process of using the ALTAIR radar located on Kwajelein Atoll to obtain radar observations of sporadic and shower meteoroids. The goals are to determine meteoroid masses, orbits, ballistic coefficients and densities, which shall be provided to the Meteoroid Environment Office (MEO) at Marshall Space Flight Center. These data and analyses shall then be used by the MEO to 1) Add a realistic density distribution to the new Meteoroid Engineering Model (MEM), which is the specified environment for vehicle design in the NASA Constellation (return to Moon) program. This program is the implementation of President Bush's Vision for Space Exploration (VSE). 2) Investigate the meteoroid velocity distribution at smaller masses. 3) Strive to understand the differences (biases) in meteoroid observations produced by systems like ALTAIR and those of the meteor patrol radars, such as the University of Western Ontario's CMOR system. This paper outlines the program details and its progress.

  5. High temperature condensates among meteors

    NASA Technical Reports Server (NTRS)

    Wilkening, L. L.

    1975-01-01

    It is noted that two meteors which exhibited no lines of iron or sodium in their spectra have been tentatively attributed to aubrites in order to explain their lack of iron. It is shown, however, that no meteorites, including aubrites, have simultaneously low abundances of iron and sodium and that possible parent materials other than aubrites must be considered for the observed meteors. Other possible parent materials considered in this letter include melilite and diopside, two minerals containing both Ca and Mg but neither Fe nor Na. It is suggested that meteoroids rich in Ca and Mg but lacking Fe and Na might form a reservoir for the so-called 'lost' elements (Ca, Mg, Al, Ti, the lanthanides, and other refractory elements) which are depleted in ordinary and enstatite chondrites relative to cosmic abundances.

  6. Meteors in the Earth's Atmosphere

    NASA Astrophysics Data System (ADS)

    Murad, Edmond; Williams, Iwan P.

    2002-09-01

    1. Introduction Iwan Williams and Edmond Murad; 2. The evolution of meteoroid streams Iwan Williams; 3. Space dust measurements Eberhard Grun, Valeri Dikarev, Harald Kruger and Markus Landgraf; 4. Extraterrestrial dust in the near-Earth environment George Flynn; 5. Detection and analysis procedures for visual photographic and image intensified CCD meteor observations Robert Hawkes; 6. Radar observations W. Jack Baggaley; 7. Meteor trails as observed by Lidar Ulf von Zahn, J. Hoffner and William McNeil; 8. In situ measurements of meteoritic ions Joseph Grebowsky and Arthur Aikin; 9. Collected extraterrestrial materials: interplanetary dust particles, micrometeorites, meteorites, and meteoritic dust Frans Rietmeijer; 10. Meteoroid impacts on spacecraft; Luigi Foschini; 11. Models of meteoritic metals in the atmosphere William McNeil, Edmond Murad and John Plane; 12. Laboratory studies of meteoritic metal chemistry John Plane; 13. Summary and future outlook Edmond Murad and Iwan Williams.

  7. Kharkiv Meteor Radar System (the XX Age)

    NASA Astrophysics Data System (ADS)

    Kolomiyets, S. V.

    2012-09-01

    Kharkiv meteor radar research are of historic value (Kolomiyets and Sidorov 2007). Kharkiv radar observations of meteors proved internationally as the best in the world, it was noted at the IAU General Assembly in 1958. In the 1970s Kharkiv meteor automated radar system (MARS) was recommended at the international level as a successful prototype for wide distribution. Until now, this radar system is one of the most sensitive instruments of meteor radars in the world for astronomical observations. In 2004 Kharkiv meteor radar system is included in the list of objects which compose the national property of Ukraine. Kharkiv meteor radar system has acquired the status of the important historical astronomical instrument in world history. Meteor Centre for researching meteors in Kharkiv is a analogue of the observatory and performs the same functions of a generator and a battery of special knowledge and skills (the world-famous studio). Kharkiv and the location of the instrument were brand points on the globe, as the place where the world-class meteor radar studies were carried out. They are inscribed in the history of meteor astronomy, in large letters and should be immortalized on a world-wide level.

  8. Meteor Observations as Big Data Citizen Science

    NASA Astrophysics Data System (ADS)

    Gritsevich, M.; Vinkovic, D.; Schwarz, G.; Nina, A.; Koschny, D.; Lyytinen, E.

    2016-12-01

    Meteor science represents an excellent example of the citizen science project, where progress in the field has been largely determined by amateur observations. Over the last couple of decades technological advancements in observational techniques have yielded drastic improvements in the quality, quantity and diversity of meteor data, while even more ambitious instruments are about to become operational. This empowers meteor science to boost its experimental and theoretical horizons and seek more advanced scientific goals. We review some of the developments that push meteor science into the Big Data era that requires more complex methodological approaches through interdisciplinary collaborations with other branches of physics and computer science. We argue that meteor science should become an integral part of large surveys in astronomy, aeronomy and space physics, and tackle the complexity of micro-physics of meteor plasma and its interaction with the atmosphere. The recent increased interest in meteor science triggered by the Chelyabinsk fireball helps in building the case for technologically and logistically more ambitious meteor projects. This requires developing new methodological approaches in meteor research, with Big Data science and close collaboration between citizen science, geoscience and astronomy as critical elements. We discuss possibilities for improvements and promote an opportunity for collaboration in meteor science within the currently established BigSkyEarth http://bigskyearth.eu/ network.

  9. SPA Meteor Section Results: 2006

    NASA Astrophysics Data System (ADS)

    McBeath, Alastair

    2010-12-01

    A summary of the main analyzed results and other information provided to the SPA Meteor Section from 2006 is presented and discussed. Events covered include: the radio Quadrantid maximum on January 3/4; an impressive fireball seen from parts of England, Belgium and the Netherlands at 22h53m51s UT on July 18, which was imaged from three EFN stations as well; the Southern delta-Aquarid and alpha-Capricornid activity from late July and early August; the radio Perseid maxima on August 12/13; confirmation that the October 5/6 video-meteor outburst was not observed by radio; visual and radio findings from the strong, bright-meteor, Orionid return in October; another impressive UK-observed fireball on November 1/2, with an oil painting of the event as seen from London; the Leonids, which produced a strong visual maximum around 04h-05h UT on November 18/19 that was recorded much less clearly by radio; radio and visual reports from the Geminids, with a note regarding NASA-observed Geminid lunar impact flashes; and the Ursid outburst recorded by various techniques on December 22.

  10. Big data era in meteor science

    NASA Astrophysics Data System (ADS)

    Vinković, D.; Gritsevich, M.; Srećković, V.; Pečnik, B.; Szabó, G.; Debattista, V.; Škoda, P.; Mahabal, A.; Peltoniemi, J.; Mönkölä, S.; Mickaelian, A.; Turunen, E.; Kákona, J.; Koskinen, J.; Grokhovsky, V.

    2016-01-01

    Over the last couple of decades technological advancements in observational techniques in meteor science have yielded drastic improvements in the quality, quantity and diversity of meteor data, while even more ambitious instruments are about to become operational. This empowers meteor science to boost its experimental and theoretical horizons and seek more advanced science goals. We review some of the developments that push meteor science into the big data era that requires more complex methodological approaches through interdisciplinary collaborations with other branches of physics and computer science. We argue that meteor science should become an integral part of large surveys in astronomy, aeronomy and space physics, and tackle the complexity of micro-physics of meteor plasma and its interaction with the atmosphere.

  11. Automated Crater Delineation

    NASA Astrophysics Data System (ADS)

    Marques, J. S.; Pina, P.

    2015-05-01

    An algorithm to delineate impact craters based on Edge Maps and Dynamic Programming is presented. The global performance obtained on 1045 craters from Mars (5 m to about 200 km in diameter), achieved 96% of correct contour delineations.

  12. Crater Wall and Floor

    NASA Image and Video Library

    2003-02-18

    The impact crater observed in this NASA Mars Odyssey image taken in Terra Cimmeria suggests sediments have filled the crater due to the flat and smooth nature of the floor compared to rougher surfaces at higher elevations.

  13. Fresh Crater with Gullies

    NASA Image and Video Library

    2010-11-12

    The crater shown in this image from NASA Mars Reconnaissance Orbiter has very few craters superposed on it, which attests to its youth. It also has very steep slopes and a sharp rim; more evidence of its young age.

  14. Rabe Crater Dunes IR

    NASA Image and Video Library

    2009-10-20

    The Thermal Emission Imaging System aboard NASA Mars Odyssey captured this daytime infrared image of Rabe Crater shows the large dune field located within the crater. Note that the dunes are not confined to the lowest elevation depressions on the

  15. Meteor Beliefs Project: Meteoric Imagery in SF, Part V: This Island Earth

    NASA Astrophysics Data System (ADS)

    McBeath, Alastair; Gheorghe, Andrei Dorian

    2007-04-01

    The classic 1950s science fiction film This Island Earth is discussed for its meteoric elements, along with a more recent movie which pokes fun at it, by way of celebrating the Meteor Beliefs Project's fourth anniversary.

  16. The Upsilon Pegasid Meteor Shower

    NASA Astrophysics Data System (ADS)

    Povenmire, H.

    1995-09-01

    On the morning of August 8, 1975, meteors were observed from a previously unrecognized radiant in Pegasus. The rates were approximately seven per hour [1]. The radiant was alpha = 350 degrees, delta = +19 degrees (2000.0). These meteors are characterized as swift, yellow-white and without significant ionization trains [1]. The average magnitude of several hundred meteors from this shower is approximately +3.50, slightly fainter than the Perseids which occur at the same time. A broad maximum seems to occur about August 8. The three active fireball networks (Prairie, MORP and European) were contacted in a search for previously recorded fireballs with negative results. Ceplecha [2] of the European Network computed the orbital elements using the FIRBAL program. On August 19, 1982 at 02:09:57 UT, a magnitude -14.76 f1reball occurred over the White Carpathian Mountains of Austria and Czechoslovakia. It was photographed by five cameras of the European Network. Reduction of this Upsilon Pegasid fireball (EN 190882A) showed it to be a type IIIb fireball [2] - that is, an extremely low density, cometary, snow-like material with a specific gravity of approximately 0.27 g/cm^3. This material ablates at high altitude and cannot produce sonic phenomena or meteorites. It is similar to the material in the Draconid meteor shower. The orbital elements derived from EN 190882A are given in Table I. Table I: Orbital elements for the Upsilon Pegasid stream from EN 190882A. omega = 305.9009 degrees Omega = 145.3431 degrees i = 85.0817 degrees q = 0.2022 e = 1.0 velocity = 51.8608 km/s Using these refined elements, Kronk [3] computed the radiant drift. The radiant drifts from the SSW to NNE at a relatively steep angle and at an average rate of 20 arc-min per day. An intensive literature search [3] revealed four double station Upsilon Pegasids which had previously been listed as sporadics. Institutions providing these data were Yale [4], Stalinabad [5], Tadjikistan [6] and Harvard [7

  17. 1. VIEW OF ARIZONA FALLS ON THE ARIZONA CANAL, PRIOR ...

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

    1. VIEW OF ARIZONA FALLS ON THE ARIZONA CANAL, PRIOR TO CONSTRUCTION OF POWER PLANT IN 1901, FACING EAST Photographer: unknown. No date. - Arizona Canal, North of Salt River, Phoenix, Maricopa County, AZ

  18. Dynasonde Measurements of Ionospheric Meteor Effects

    NASA Astrophysics Data System (ADS)

    Berkey, F. T.; Sikdar, P.; Fish, C. S.; Jones, O.; Tsai, L.; Yen, C.

    2002-12-01

    The ionization created when meteoric particles impinge on the upper atmosphere has been studied extensively, both with optical methods and by radar techniques. Traditionally, meteor radars have been configured as dedicated, fixed-frequency systems that operate in the HF/VHF bands and are employed to measure winds and other parameters in the mesosphere-lower thermosphere region. It has long been recognized that ionosondes are capable of detecting meteor ionization although the sparse sounding format of most synoptic instruments does not facilitate a rigorous analysis of meteor ionization effects. Furthermore, most ionosonde-based studies have focused on meteor shower intervals when the meteor ionization is especially prominent (e.g. Chandra et. al., 2001). However, the capabilities of digital ionosondes such as the NOAA dynasonde allow the detailed study of various parameters of the meteor-induced ionization such as amplitude, polarization and spatial location, in addition to the time-of-flight, as a function of time and frequency. In this report, we will examine meteor ionization recorded by dynasondes located at Bear Lake (Utah) and Halley (Antarctica) demonstrating that these ionogram data can be used to distinguish between underdense and overdense meteor ionization. Other characteristics of the meteor-induced ionization, such as spatial location and Doppler velocity will also be presented. The dynasonde operated at the USU Bear Lake Observatory (42° N, 111° W) detects a large flux of meteor echoes and will be the primary source of data for this study. Chandra, H., et. al., Sporadic-E associated with the Leonid meteor shower event of November 1998 over low and equatorial latitudes, Annales. Geophys., 19, 59-69, 2001.

  19. On the very high velosity meteors

    NASA Astrophysics Data System (ADS)

    Hajduk, A.

    2001-11-01

    The reexamination of radar methods used in the AMOR meteor project for the determination of meteor velocities leads to the conclusion that the sets of highly hyperbolic velocities in the range 100 - 500 km s-1, based on the time-lag method and its combinations, cannot be accepted, until the approval of this dataset by means of suggested tests of meteor astronomy is not made. Therefore, also the conclusions based on these highly hyperbolic orbits, derived from AMOR system needs some revision.

  20. A Triple Crater

    NASA Image and Video Library

    2017-06-01

    This image from NASA's Mars Reconnaissance Orbiter shows an elongated depression from three merged craters. The raised rims and ejecta indicate that these are impact craters rather than collapse or volcanic landforms. The pattern made by the ejecta and the craters suggest this was a highly oblique (low angle to the surface) impact, probably coming from the west. There may have been three major pieces flying in close formation to make this triple crater. https://photojournal.jpl.nasa.gov/catalog/PIA21652

  1. Dome craters on Ganymede

    NASA Technical Reports Server (NTRS)

    Moore, J. M.; Malin, M. C.

    1987-01-01

    Voyager observations reveal impact craters on Ganymede that are characterized by the presence of broad, high albedo, topographic domes situated within a central pit. Fifty-seven craters with central domes were identified in images covering approx. 50% of the surface. Owing to limitations in resolution, and viewing and illumination angles, the features identified are most likely a subset of dome craters. The sample appears to be sufficiently large to infer statistically meaningful trends. Dome craters appear to fall into two distinct populations on plots of the ratio of dome diameter to crater rim diameter, large-dome craters and small-dome craters. The two classes are morphologically distinct from one another. In general, large dome craters show little relief and their constituent landforms appear subdued with respect to fresh craters. The physical attributes of small-dome craters are more sharply defined, a characteristic they share with young impact craters of comparable size observed elsewhere in the solar system. Both types of dome craters exhibit central pits in which the dome is located. As it is difficult to produce domes by impact and/or erosional processes, an endogenic origin for the domes is reasonably inferred. Several hypotheses for their origin are proposed. These hypotheses are briefly reviewed.

  2. Dione Ray Crater

    NASA Image and Video Library

    2012-10-01

    NASA Cassini spacecraft looks at an example of a ray crater on the leading hemisphere of Saturn moon Dione. The ray crater is in the upper-left of the image and ejecta rays show up as brighter material emanating from the crater.

  3. Venus - Stein Triplet Crater

    NASA Image and Video Library

    1996-01-29

    NASA Magellan synthetic aperture radar SAR imaged this unique triplet crater, or crater field during orbits 418-421 on Sept. 21, 1990. The three craters appear to have relatively steep walls. http://photojournal.jpl.nasa.gov/catalog/PIA00088

  4. Venus - Adivar Crater

    NASA Image and Video Library

    1996-02-07

    Many of the impact craters of Venus revealed by NASA Magellan spacecraft have characteristics unlike craters on any other planetary body. This crater, named Adivar, is located just north of the western Aphrodite highland. http://photojournal.jpl.nasa.gov/catalog/PIA00083

  5. Crater Impacts on Vesta

    NASA Image and Video Library

    2012-05-10

    This graphic shows the global distribution of craters that hit the giant asteroid Vesta, based on data from NASA Dawn mission. The yellow circles indicate craters of 2 miles or wider, with the size of the circles indicating the size of the crater.

  6. Vesta Cratered Landscape: Double Crater and Craters with Bright Ejecta

    NASA Image and Video Library

    2011-11-23

    This image from NASA Dawn spacecraft is dominated by a double crater which may have been formed by the simultaneous impact of a binary asteroid. Binary asteroids are asteroids that orbit their mutual center of mass.

  7. Impact craters on Titan

    USGS Publications Warehouse

    Wood, C.A.; Lorenz, R.; Kirk, R.; Lopes, R.; Mitchell, Ken; Stofan, E.

    2010-01-01

    Five certain impact craters and 44 additional nearly certain and probable ones have been identified on the 22% of Titan's surface imaged by Cassini's high-resolution radar through December 2007. The certain craters have morphologies similar to impact craters on rocky planets, as well as two with radar bright, jagged rims. The less certain craters often appear to be eroded versions of the certain ones. Titan's craters are modified by a variety of processes including fluvial erosion, mass wasting, burial by dunes and submergence in seas, but there is no compelling evidence of isostatic adjustments as on other icy moons, nor draping by thick atmospheric deposits. The paucity of craters implies that Titan's surface is quite young, but the modeled age depends on which published crater production rate is assumed. Using the model of Artemieva and Lunine (2005) suggests that craters with diameters smaller than about 35 km are younger than 200 million years old, and larger craters are older. Craters are not distributed uniformly; Xanadu has a crater density 2-9 times greater than the rest of Titan, and the density on equatorial dune areas is much lower than average. There is a small excess of craters on the leading hemisphere, and craters are deficient in the north polar region compared to the rest of the world. The youthful age of Titan overall, and the various erosional states of its likely impact craters, demonstrate that dynamic processes have destroyed most of the early history of the moon, and that multiple processes continue to strongly modify its surface. The existence of 24 possible impact craters with diameters less than 20 km appears consistent with the Ivanov, Basilevsky and Neukum (1997) model of the effectiveness of Titan's atmosphere in destroying most but not all small projectiles. ?? 2009 Elsevier Inc.

  8. Impact craters on Titan

    USGS Publications Warehouse

    Wood, Charles A.; Lorenz, Ralph; Kirk, Randy; Lopes, Rosaly; Mitchell, Karl; Stofan, Ellen; ,

    2010-01-01

    Five certain impact craters and 44 additional nearly certain and probable ones have been identified on the 22% of Titan's surface imaged by Cassini's high-resolution radar through December 2007. The certain craters have morphologies similar to impact craters on rocky planets, as well as two with radar bright, jagged rims. The less certain craters often appear to be eroded versions of the certain ones. Titan's craters are modified by a variety of processes including fluvial erosion, mass wasting, burial by dunes and submergence in seas, but there is no compelling evidence of isostatic adjustments as on other icy moons, nor draping by thick atmospheric deposits. The paucity of craters implies that Titan's surface is quite young, but the modeled age depends on which published crater production rate is assumed. Using the model of Artemieva and Lunine (2005) suggests that craters with diameters smaller than about 35 km are younger than 200 million years old, and larger craters are older. Craters are not distributed uniformly; Xanadu has a crater density 2-9 times greater than the rest of Titan, and the density on equatorial dune areas is much lower than average. There is a small excess of craters on the leading hemisphere, and craters are deficient in the north polar region compared to the rest of the world. The youthful age of Titan overall, and the various erosional states of its likely impact craters, demonstrate that dynamic processes have destroyed most of the early history of the moon, and that multiple processes continue to strongly modify its surface. The existence of 24 possible impact craters with diameters less than 20 km appears consistent with the Ivanov, Basilevsky and Neukum (1997) model of the effectiveness of Titan's atmosphere in destroying most but not all small projectiles.

  9. Degraded Crater Rim

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 3 May 2002) The Science The eastern rim of this unnamed crater in Southern Arabia Terra is very degraded (beaten up). This indicates that this crater is very ancient and has been subjected to erosion and subsequent bombardment from other impactors such as asteroids and comets. One of these later (younger) craters is seen in the upper right of this image superimposed upon the older crater rim material. Note that this smaller younger crater rim is sharper and more intact than the older crater rim. This region is also mantled with a blanket of dust. This dust mantle causes the underlying topography to take on a more subdued appearance. The Story When you think of Arabia, you probably think of hot deserts and a lot of profitable oil reserves. On Mars, however, Southern Arabia Terra is a cold place of cratered terrain. This almost frothy-looking image is the badly battered edge of an ancient crater, which has suffered both erosion and bombardment from asteroids, comets, or other impacting bodies over the long course of its existence. A blanket of dust has also settled over the region, which gives the otherwise rugged landscape a soft and more subdued appearance. The small, round crater (upper left) seems almost gemlike in its setting against the larger crater ring. But this companionship is no easy romance. Whatever formed the small crater clearly whammed into the larger crater rim at some point, obliterating part of its edge. You can tell the small crater was formed after the first and more devastating impact, because it is laid over the other larger crater. How much younger is the small one? Well, its rim is also much sharper and more intact, which gives a sense that it is probably far more youthful than the very degraded, ancient crater.

  10. Planetary cratering - Statistical recognition of secondary-crater fields

    NASA Astrophysics Data System (ADS)

    Fulchignoni, M.; Poscolieri, M.

    1980-06-01

    A statistical model of a cratered planetary surface is developed for the cases of primary impact events and a secondary crater field. The method of the strictly reflexive closeness of crater centers is used to test the crater-grouping tendency. Results show the differences, with regard to grouping probability, between a population of fictitious craters and that including a secondary field. Several crater surfaces on Mars and Mercury were studied by this method, and an upper limit for crater density was determined.

  11. Northern Arizona Volcanoes

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Northern Arizona is best known for the Grand Canyon. Less widely known are the hundreds of geologically young volcanoes, at least one of which buried the homes of local residents. San Francisco Mtn., a truncated stratovolcano at 3887 meters, was once a much taller structure (about 4900 meters) before it exploded some 400,000 years ago a la Mt. St. Helens. The young cinder cone field to its east includes Sunset Crater, that erupted in 1064 and buried Native American homes. This ASTER perspective was created by draping ASTER image data over topographic data from the U.S. Geological Survey National Elevation Data.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

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

    Size: 20.4 by 24.6 kilometers (12.6 by 15.2 miles) Location: 35.3 degrees North latitude, 111

  12. Possible Layers on Floor of Suzhi Crater

    NASA Image and Video Library

    2016-12-14

    This image shows the floor of Suzhi Crater, an approximately 25-kilometer diameter impact crater located northeast of Hellas Planitia. The crater floor is mostly covered by dark-toned deposits; however some patches of the underlying light-toned bedrock are now exposed, like in this Context Camera image. This enhanced-color infrared image shows a close up of the exposed bedrock on the floor of the crater. Here we can see the lighter-toned bedrock partially covered up by darker-toned bedrock and a few wind-blown bedforms. The lighter-toned bedrock appears to lie over yet another type of bedrock in our image, which appears to be yellowish and heavily fractured. What complex tale of Martian geologic and climate history might these rocks tell us if we were able to sample them in person? Perhaps, one day we'll know. The University of Arizona, Tucson, operates HiRISE, which was http://photojournal.jpl.nasa.gov/catalog/PIA21273

  13. Large Crater Clustering tool

    NASA Astrophysics Data System (ADS)

    Laura, Jason; Skinner, James A.; Hunter, Marc A.

    2017-08-01

    In this paper we present the Large Crater Clustering (LCC) tool set, an ArcGIS plugin that supports the quantitative approximation of a primary impact location from user-identified locations of possible secondary impact craters or the long-axes of clustered secondary craters. The identification of primary impact craters directly supports planetary geologic mapping and topical science studies where the chronostratigraphic age of some geologic units may be known, but more distant features have questionable geologic ages. Previous works (e.g., McEwen et al., 2005; Dundas and McEwen, 2007) have shown that the source of secondary impact craters can be estimated from secondary impact craters. This work adapts those methods into a statistically robust tool set. We describe the four individual tools within the LCC tool set to support: (1) processing individually digitized point observations (craters), (2) estimating the directional distribution of a clustered set of craters, back projecting the potential flight paths (crater clusters or linearly approximated catenae or lineaments), (3) intersecting projected paths, and (4) intersecting back-projected trajectories to approximate the local of potential source primary craters. We present two case studies using secondary impact features mapped in two regions of Mars. We demonstrate that the tool is able to quantitatively identify primary impacts and supports the improved qualitative interpretation of potential secondary crater flight trajectories.

  14. Impact Crater Collapse

    NASA Astrophysics Data System (ADS)

    Melosh, H. J.; Ivanov, B. A.

    The detailed morphology of impact craters is now believed to be mainly caused by the collapse of a geometrically simple, bowl-shaped "transient crater." The transient crater forms immediately after the impact. In small craters, those less than approximately 15 km diameter on the Moon, the steepest part of the rim collapses into the crater bowl to produce a lens of broken rock in an otherwise unmodified transient crater. Such craters are called "simple" and have a depth-to-diameter ratio near 1:5. Large craters collapse more spectacularly, giving rise to central peaks, wall terraces, and internal rings in still larger craters. These are called "complex" craters. The transition between simple and complex craters depends on 1/g, suggesting that the collapse occurs when a strength threshold is exceeded. The apparent strength, however, is very low: only a few bars, and with little or no internal friction. This behavior requires a mechanism for temporary strength degradation in the rocks surrounding the impact site. Several models for this process, including acoustic fluidization and shock weakening, have been considered by recent investigations. Acoustic fluidization, in particular, appears to produce results in good agreement with observations, although better understanding is still needed.

  15. Grand Canyon in Colorado Plateau in Arizona as seen from Apollo 9

    NASA Image and Video Library

    1969-03-09

    AS09-20-3137 (3-13 March 1969) --- The Grand Canyon is sharply etched on the snow-covered Colorado Plateau in Arizona in this photograph from the Apollo 9 spacecraft during its Earth-orbital mission. Lake Powell behind Glen Canyon Dam is in the upper right corner. Humphreys Peak and the many volcanic craters around the San Francisco Mountains near Flagstaff, Arizona, are right of center. Prescott is under clouds at lower center.

  16. Martian Central Pit Craters

    NASA Technical Reports Server (NTRS)

    Hillman, E.; Barlow, N. G.

    2005-01-01

    Impact craters containing central pits are rare on the terrestrial planets but common on icy bodies. Mars is the exception among the terrestrial planets, where central pits are seen on crater floors ( floor pits ) as well as on top of central peaks ( summit pits ). Wood et al. [1] proposed that degassing of subsurface volatiles during crater formation produced central pits. Croft [2] argued instead that central pits might form during the impact of volatile-rich comets. Although central pits are seen in impact craters on icy moons such as Ganymede, they do show some significant differences from their martian counterparts: (a) only floor pits are seen on Ganymede, and (b) central pits begin to occur at crater diameters where the peak ring interior morphology begins to appear in terrestrial planet craters [3]. A study of craters containing central pits was conducted by Barlow and Bradley [4] using Viking imagery. They found that 28% of craters displaying an interior morphology on Mars contain central pits. Diameters of craters containing central pits ranged from 16 to 64 km. Barlow and Bradley noted that summit pit craters tended to be smaller than craters containing floor pits. They also noted a correlation of central pit craters with the proposed rings of large impact basins. They argued that basin ring formation fractured the martian crust and allowed subsurface volatiles to concentrate in these locations. They favored the model that degassing of the substrate during crater formation was responsible for central pit formation due to the preferential location of central pit craters along these basin rings.

  17. An assessment of crater erosional histories on the Earth and Mars using digital terrain models.

    NASA Astrophysics Data System (ADS)

    Paul, R. L.; Muller, J.-P.; Murray, J. B.

    The research will examine quantitatively the geomorphology of both Terrestrial and Martian craters. The erosional and sub-surface processes will be investigated to understand how these affect a crater's morphology. For example, the Barringer crater in Arizona has an unusual shape. The Earth has a very high percentage of water both in the atmosphere as clouds or rain and under the surface. The presence of water will therefore affect a crater's formation and its subsequent erosional modification. On Mars there is little or no water present currently, though recent observations suggest there may be near-surface ice in some areas. How do craters formed in the Martian environment therefore differ from Terrestrial ones? How has the structure of Martian craters changed in areas of possible fluvial activity? How does the surface material affect crater formation? How does the Earth's fluvial activity affect a crater's evolution? At present, four measurements of circularity have been used to describe a crater (Murray & Guest, 1972). These parameters will be re-examined to see how effectively they describe Terrestrial and Martian craters using high resolution DTMs which were not available at the time of the original study. The model described by Forsberg-Taylor et al. 2004, and others will also be applied to results obtained from the chosen craters to assess how effectively these craters are described. Both hypsometric curves and hydrological analysis will be used to assess crater evolution. A suitable criterion for the selection of Terrestrial and Martian craters is essential for this type of research. Terrestrial craters have been selected in arid or semi-arid terrain with crater diameters larger than one kilometre. Craters less than five million years old would be ideal. However, this was too restrictive and so a variety of crater ages have had to be used. Eight terrestrial craters have been selected in arid or semi-arid areas for study, using the Earth Impact Database and

  18. ScienceCast 20: Summer Meteor Shower

    NASA Image and Video Library

    2011-07-21

    If you're camping out and can't sleep, maybe your slumber is being interrupted by the flash of meteors. The summer Perseid meteor shower is getting underway as Earth enters the debris stream from comet Swift-Tuttle.

  19. Meteor spectra in the EDMOND database

    NASA Astrophysics Data System (ADS)

    Koukal, J.; Gorková, S.; Srba, J.; Ferus, M.; Civiš, S.; di Pietro, C. A.

    2015-01-01

    We present a selection of five interesting meteor spectra obtained in the years 2014 and 2015 via CCTV video systems with a holographic grating, working in CEMENT and BRAMON meteor observation networks. Based on the EDMOND multi stations video meteor trajectory data an orbital classification of these meteors was performed. Selected meteors are members of the LYR, SPE, DSA and LVI meteor streams, one meteor is classified as sporadic background (SPO). In calibrated spectra the main chemical components were identified. Meteors are chemically classified based on relative intensities of the main spectral lines (or multiplets): Mg I (2), Na I (1), and Fe I (15). Bolide EN091214 is linked with the 23rd meteorite with known orbit (informally known as "Žďár"), two fragments of the parent body were found in the Czech Republic so far (August, 2015). For this particular event a time resolved spectral observation and comparison with laboratory spectra of LL3.2 chondritic meteorite are presented.

  20. Meteor radio detection. (Italian Title: Radiometeore, oggi)

    NASA Astrophysics Data System (ADS)

    Aglialoro, A.; Devetti, M.

    2013-08-01

    Meteor detection using the radio technique called "Meteor-Scatter" and some results obtained since 2005 by our team. This kind of activity has become difficult after the switch-off of analog TV; a hope may be a French VHF trasmitter: the Graves radar.

  1. Models of sporadic meteor body distributions

    NASA Technical Reports Server (NTRS)

    Andreev, V. V.; Belkovich, O. I.

    1987-01-01

    The distribution of orbital elements and flux density over the celestial sphere are the most common forms of representation of the meteor body distribution in the vicinity of the Earth's orbit. The determination of flux density distribution of sporadic meteor bodies was worked out. The method and its results are discussed.

  2. Meteor Terminology poster translated into different languages

    NASA Astrophysics Data System (ADS)

    Perlerin, Vincent; Hankey, Mike

    2014-02-01

    The American Meteor Society (AMS) has created an educational poster that defines the major terms of the meteor terminology. This poster is an educational tool made available for free on the AMS website. We offer this poster to be translated and shared among the IMO members.

  3. Croatian Meteor Network: ongoing work 2014 - 2015

    NASA Astrophysics Data System (ADS)

    Šegon, D.; Andreić, Ž.; Korlević, K.; Vida, D.

    2015-01-01

    Ongoing work mainly between 2014-2015 International Meteor Conferences (IMC) has been presented. Current sky coverage, software updates, orbit catalogues updates, shower search updates, international collaboration as well as new fields of research and educational efforts made by the Croatian Meteor Network are described.

  4. Commission 22: Meteors, Meteorites and Interplanetary Dust

    NASA Astrophysics Data System (ADS)

    Spurný, Pavel; Watanabe, Jun-ichi; Mann, Ingrid; Borovička, Jiří; Baggaley, William J.; Brown, Peter G.; Consolmagno, Guy J.; Jenniskens, Peter M. M.; Pellinen-Wannberg, Asta K.; Porubčan, Vladimír; Williams, Iwan P.; Yano, Hajime

    Commission 22 is part of Division III on Planetary System Sciences of the International Astronomical Union. Members of Commission 22 are professional scientists studying bodies in the Solar System smaller than asteroids and comets, and their interactions with planets. The main subjects of interest are meteors, meteoroids, meteoroid streams, interplanetary dust particles, and also zodiacal cloud, meteor trains, meteorites, tektites, etc.

  5. The Makings of Meteor Astronomy: Part XIII

    NASA Astrophysics Data System (ADS)

    Beech, M.

    1996-10-01

    In 1848, Sir John Lubbock advanced the hypothesis that meteors shine by reflected sunlight. He developed a set of equations describing the geometry of meteor encounters, and for a decade or so, his idea was at least marginally supported by other observers.

  6. Northern Arizona University

    ERIC Educational Resources Information Center

    Butcher, Michael F.; Saltonstall, Margot; Bickel, Sarah; Brandel, Rick

    2009-01-01

    Northern Arizona University (NAU) is a public university nestled below the San Francisco Peaks in Flagstaff, Arizona. It enrolls more than 21,000 undergraduate and graduate students at its main campus in Flagstaff, through its 35 statewide sites, and via online program offerings. Within the university organizational system, Student Affairs has a…

  7. Northern Arizona University

    ERIC Educational Resources Information Center

    Butcher, Michael F.; Saltonstall, Margot; Bickel, Sarah; Brandel, Rick

    2009-01-01

    Northern Arizona University (NAU) is a public university nestled below the San Francisco Peaks in Flagstaff, Arizona. It enrolls more than 21,000 undergraduate and graduate students at its main campus in Flagstaff, through its 35 statewide sites, and via online program offerings. Within the university organizational system, Student Affairs has a…

  8. Arizona Charter Schools Handbook.

    ERIC Educational Resources Information Center

    Arizona State Dept. of Education, Phoenix.

    This handbook provides information and materials to assist applicants in preparing an application to establish a charter school in Arizona. The topics discussed reflect the technical requirements of Arizona's charter-school legislation. It does not necessarily reflect the selection requirements or the policies of the State Board of Education, the…

  9. Impact cratering: A geologic process

    NASA Technical Reports Server (NTRS)

    Melosh, H. J.

    1989-01-01

    The mechanisms involved in the formation of impact craters are examined theoretically, reviewing the results of recent investigations. Topics addressed include crater morphology, stress waves in solids, the contact and compression stage, the excavation stage, and ejecta deposits. Consideration is given to the scaling of crater dimensions, the crater modification stage, multiring basins, cratered landscapes, atmospheric interactions, and the implications of impact cratering for planetary evolution. Extensive diagrams, graphs, tables, and images of typical craters are provided.

  10. Impact cratering: A geologic process

    NASA Astrophysics Data System (ADS)

    Melosh, H. J.

    The mechanisms involved in the formation of impact craters are examined theoretically, reviewing the results of recent investigations. Topics addressed include crater morphology, stress waves in solids, the contact and compression stage, the excavation stage, and ejecta deposits. Consideration is given to the scaling of crater dimensions, the crater modification stage, multiring basins, cratered landscapes, atmospheric interactions, and the implications of impact cratering for planetary evolution. Extensive diagrams, graphs, tables, and images of typical craters are provided.

  11. The geology and mechanics of formation of the Fort Rock Dome, Yavapai County, Arizona

    USGS Publications Warehouse

    Fuis, Gary S.

    1996-01-01

    The Fort Rock Dome, a craterlike structure in northern Arizona, is the erosional product of a circular domal uplift associated with a Precambrian shear zone exposed within the crater and with Tertiary volcanism. A section of Precambrian to Quaternary rocks is described, and two Tertiary units, the Crater Pasture Formation and the Fort Rock Creek Rhyodacite, are named. A mathematical model of the doming process is developed that is consistent with the history of the Fort Rock Dome.

  12. Meteor Beliefs Project: meteoritic weapons

    NASA Astrophysics Data System (ADS)

    Kristine Larsen, K.; McBeath, A.

    2012-01-01

    A discussion of meteoritic iron weapons and weapon-like tools is given, drawing on fictional, mythological, and real-world examples. The evidence suggests that no great significance was attached to such metal purely because of its "heavenly" provenance prior to the early 19th century AD, despite later assumptions, including during the period of increased interest in meteorites, cratering events and the early usage of meteoritic iron, beginning in the early 20th century.

  13. Impact cratering on slopes

    NASA Astrophysics Data System (ADS)

    Aschauer, Johannes; Kenkmann, Thomas

    2017-07-01

    The majority of impact craters have circular outlines and axially symmetric morphologies. Deviation from crater circularity is caused by either target heterogeneity, a very oblique impact incidence, post-impact deformation, or by topography. Here, we investigate the effect of topography on crater formation and systematically study impact cratering processes on inclined hillsides up to 25° slope utilizing analogue experiments. A spring-driven air gun mounted in a vertical position shoots into three different types of granular bulk solids (two sorts of glass beads, quartz sand) to emulate impact cratering on slopes. In all, 170 experiments were conducted. The transient crater develops roughly symmetrically perpendicular to the slope plane, resulting in higher ejection angles uphill than downhill when measured with respect to a horizontal plane. Craters become increasingly elliptical with increasing slope angle. At slope angles close to angle of repose of the respective bulk solids, aspect ratios of the craters reach ∼1.7. Uphill-downhill cross sections become increasingly asymmetric, the depth-diameter ratio of the craters decreases, and the deepest point shifts downhill with increasing slope angle. Mass wasting is initiated both in the uphill and downhill sectors of the crater rim. For steep slopes the landslides that emanate from the uphill rim can overshoot the crater cavity and superpose the downhill crater rim in a narrow tongue. Mass wasting initiated at the downhill sector forms broader and shallower tongues and is triggered by the deposition of ejecta on the inclined slope. Our experiments help to explain asymmetric crater morphologies observed on asteroids such as Ceres, Vesta, Lutetia, and also on Mars.

  14. Simulated Craters on Venus

    NASA Technical Reports Server (NTRS)

    Zahnle, Kevin; Cuzzi, Jeffrey N. (Technical Monitor)

    1995-01-01

    The thick atmosphere of Venus prevents all but the largest impactors from cratering the surface. The number of small craters on Venus provides an interesting, and statistically significant test of models for the disruption and deceleration of impacting bodies. Here we compare Monte Carlo simulated crater distributions to the observed crater distribution on Venus. The simulation assumes: (1) a power law mass distribution for impactors of the form N(sub cum) alpha m (exp-b) where b=0.8; (2) isotropic incidence angles; (3) velocity at the top of the atmosphere of 20 kilometers per second (more realistic velocity distributions are also considered); (4) Schmidt-Housen crater scaling, modified such that only the normal component of the impact velocity contributes to cratering, and using crater slumping as parameterized (5) and modern populations (60% carbonaceous, 40% stone, 3% iron) and fluxes of asteroids. We use our previously developed model for the disruption and deceleration of large bodies striking thick planetary atmospheres to calculate the impact velocity at the surface as a function of impactor mass, incident velocity, and incident angle. We use a drag coefficient c(sub d) =1; other parameters are as described in Chyba et al. We set a low velocity cutoff of 500 meters per second on crater-forming impacts. Venus's craters are nicely matched by the simulated craters produced by 700 million years of striking asteroids. Shown for comparison are the simulated craters produced by incident comets over the same period, where for comets we have assumed b=0.7 and a flux at 10(exp 14) g 30% that of asteroids. Systematic uncertainties in crater scaling and crater slumping may make the surface age uncertain by a factor of two.

  15. Shadowed Craters on Ceres

    NASA Image and Video Library

    2016-07-08

    At the poles of Ceres, scientists have found craters that are permanently in shadow (indicated by blue markings). Such craters are called "cold traps" if they remain below about minus 240 degrees Fahrenheit (minus 151 degrees Celsius). These shadowed craters may have been collecting ice for billions of years because they are so cold. This image was created using data from NASA's Dawn spacecraft. http://photojournal.jpl.nasa.gov/catalog/PIA20696

  16. A meteor stream study of 1966

    NASA Astrophysics Data System (ADS)

    Terentjeva, Alexandra

    2017-03-01

    3600 individual photographic orbits of meteor bodies and about 2000 visual meteor radiants with corresponding velocities were compiled and carefully studied in detail. 154 minor meteor streams were detected in the Solar System, their basic orbital and other data are given. Firstly some remarkable shower and stream properties are established: examples of the large elliptic radiation areas with semi-major axes perpendicular to the Ecliptic; the existence of the Northern (N) , Southern (S) and Ecliptical (Q) branches of some streams; stream-antipodes and radiant-antipodes (symmetrically arranged relatively to the Ecliptic) with angular distances from the Ecliptic to 40-80°; a number of short-perihelion streams (q 0.05-0.07 A.U.); some meteor streams perpendicular to the Ecliptic's plane. There are also some unique meteor bodies with their orbits enclosed within the limits of the Earth's one, or having the clockwise and anticlockwise direction in two similar orbits. Hyperbolic photographic velocities vh = 57-88 km /sec are treated as real ones according to the best radar and visual observations. A "bunch" of ecliptical streams, discovered in the USSR in 1950, is a complex of orbits of the mostly massive meteor particles of the Zodiacal Cloud. The stream evolution rate is comparatively high. The total complex of sporadic meteor bodies is not totally chaotic and accidental.

  17. Research on artificial meteor trail emergency communication

    NASA Astrophysics Data System (ADS)

    Juntao, Liu; Xijun, Yan; Li, Jia

    As the particles known as meteors enter the earth's atmosphere, a small fraction of which can form ionized cloud, this ionized cloud has property useful for reflecting electromagnetic wave. Meteor burst communication is a point to point communication technology base on the above principle. Similarly, artificial meteor trail communication establishes “ionized cloud” signal channel by alkali metal ionizing at high-altitude ionosphere to reflect electromagnetic waves. Currently, Meteor burst communication is a mature communication technology with many advantages. However, as a completely uncontrollable natural phenomena, the communication time, duration time, the amount of information transmitted and antenna alignment direction are all uncontrollable. We can only figure out key parameters such as throughput and waiting time within a certain time relying on statistical regularities. Information transmission between specified sites in certain time is impossible to predict accurately. These disadvantages greatly reduce the dependability of meteor trail communication and cannot meet emergency communication’s requirements for real-time, controllable and uninterrupted. Artificial meteor trail emergency communication technology solves the above problems, it’s a reliable emergency telecommunication method. This paper focuses on the necessity and feasibility of artificial meteor trail emergency communication technology, as well as its future application.

  18. Coral Cratering Phenomenology.

    DTIC Science & Technology

    1980-10-31

    effect for producing the final crater volumes. Based on a known relationship between high-explosive cratering in coral and a similar continen- tal...mhh|hhMENENEinllmiEilEEE- IIIELJEIEOIOEIII E~hhhhhEE|hlhI �oo 96 3 DNA 5813T 0 4f CORAL CRATERING PHENOMENOLOGY R. L. LaFrenz Systems, Science...PERIOD COVERED Topical Report for Perio CORAL CRATERING PHENOMENOLOGY 1 May 77-31 Oct 80 S. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(s) 8. CONTRACT OR

  19. Messor Crater from LAMO

    NASA Image and Video Library

    2016-01-12

    This image from NASA's Dawn spacecraft shows part of Messor Crater (25 miles or 40 kilometers, wide), located at northern mid-latitudes on Ceres. The scene shows an older crater in which a large lobe-shaped flow partly covers the northern (top) part of the crater floor. The flow is a mass of material ejected when a younger crater formed just north of the rim. Dawn took this image on Dec. 19 from its low-altitude mapping orbit (LAMO) from an approximate altitude of 240 miles (385 kilometers) above Ceres. The image resolution is 120 feet (35 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20191

  20. Crater Rays on Ganymede

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This mosaic of Voyager 2 images taken July 9, 1979, shows a prominent rayed crater on Jupiter's icy moon, Ganymede. The view on the left is a monochrome image, and that on the right is the same scene shown in false color designed to accentuate the icy ejecta rays splashed out by the impact. This crater is about 150 km (93 miles) across. Like several other large craters in this scene, the rayed one has a central pit, whose origins remain speculative but may involve impact melting or solid-state fluidization of the icy crust. Bright crater rays on Ganymede, like those on our own Moon, are useful to geologists because they constitute a set of features that were laid across the moon's surface at a discrete point in time--thus they serve as time markers that can be used to establish the sequence of events that shaped Ganymede's surface. For instance, the crater rays appear to be painted over, hence are younger than, areas of grooved terrain (lower left quadrant), whereas a somewhat smaller crater at the center of the scene has icy ejecta that appears to bury (hence, post-dates) the large crater ray system. One can conclude that the grooved terrain formed first, then the large crater and its rays, and then the smaller crater and its fresh icy ejecta deposits.

  1. Venus - Stein Triplet Crater

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Magellan synthetic aperture radar (SAR) imaged this unique 'triplet crater,' or 'crater field' during orbits 418-421 on 21 September 1990. These craters are 14 kilometers, 11 kilometers, and 9 kilometers in diameter, respectively, and are centered at latitude -30.1 degrees south and longitude 345.5 degrees east. The Magellan Science Team has proposed the name Stein for this crater field after the American author, Gertrude Stein. This name has not yet been approved by the International Astronomical Union. The crater field was formed on highly fractured plains. The impacts generated a considerable amount of low viscosity 'flows' thought to consist largely of shock-melted target material along with fragmented debris from the crater. The three craters appear to have relatively steep walls based on the distortion in the image of the near and far walls of the craters in the Magellan radar look direction (from the left). The flow deposits from the three craters extend dominantly to the northeast (upper right).

  2. Planetary cratering mechanics

    NASA Astrophysics Data System (ADS)

    O'Keefe, John D.; Ahrens, Thomas J.

    1993-09-01

    The objective of this study was to obtain a quantitative understanding of the cratering process over a broad range of conditions. Our approach was to numerically compute the evolution of impact induced flow fields and calculate the time histories of the key measures of crater geometry (e.g., depth, diameter, lip height) for variations in planetary gravity (0 to 109 cm/s2), material strength (0 to 2400 kbar), and impactor radius (0.05 to 5000 km). These results were used to establish the values of the open parameters in the scaling laws of Holsapple and Schmidt (1987). We describe the impact process in terms of four regimes: (1) penetration, (2) inertial, (3) terminal, and (4) relaxation. During the penetration regime, the depth of impactor penetration grows linearly for dimensionless times τ=(Ut/a)<5.1. Here, U is projectile velocity, t is time, and a is projectile radius. In the inertial regime, τ>5.1, the crater grows at a slower rate until it is arrested by either strength or gravitational forces. In this regime, the increase of crater depth, d, and diameter, D, normalized by projectile radius is given by d/a=1.3 (Ut/a)0.36 and D/a=2.0(Ut/a)0.36. For strength-dominated craters, growth stops at the end of the inertial regime, which occurs at τ=0.33 (Yeff/ρU2)-0.78, where Yeff is the effective planetary crustal strength. The effective strength can be reduced from the ambient strength by fracturing and shear band melting (e.g., formation of pseudo-tachylites). In gravity-dominated craters, growth stops when the gravitational forces dominate over the inertial forces, which occurs at τ=0.92 (ga/U2)-0.61. In the strength and gravity regimes, the maximum depth of penetration is dp/a=0.84 (Y/ρ U2)-0.28 and dp/a=1.2 (ga/U2)-0.22, respectively. The transition from simple bowl-shaped craters to complex-shaped craters occurs when gravity starts to dominate over strength in the cratering process. The diameter for this transition to occur is given by Dt=9.0 Y/ρg, and

  3. Dusty Crater In False Color

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The theme for the weeks of 1/17 and 1/24 is the north polar region of Mars as seen in false color THEMIS images. Ice/frost will typically appear as bright blue in color; dust mantled ice will appear in tones of red/orange.

    This false color image of a crater rim illustrates just how complete the dust cover can be. The small white/blue regions on the rim are of areas where the dust cover has been removed - due to heating on sun facing slopes or by gravitational effects.

    Image information: VIS instrument. Latitude 70.1, Longitude 352.8 East (7.2 West). 40 meter/pixel resolution.

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

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

  4. A Tale of Two Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    In western Acidalia, two craters of similar size (a few km's) dramatically display the effects of geologic activity. The younger one on the left has been left relatively well preserved, retaining a sharp rim crest, a classic bowl shape, and a clearly defined ejecta blanket. The older one on the right likely has experienced a flood of lava that covered over the ejecta and filled in the bowl (note the breach in the rim). Its rim crest has been worn down by a multitude of subsequent impacts.

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

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

    Image information: VIS instrument. Latitude 35.9, Longitude 311.1 East (48.9 West). 19 meter/pixel resolution.

  5. A Tale of Two Craters

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    In western Acidalia, two craters of similar size (a few km's) dramatically display the effects of geologic activity. The younger one on the left has been left relatively well preserved, retaining a sharp rim crest, a classic bowl shape, and a clearly defined ejecta blanket. The older one on the right likely has experienced a flood of lava that covered over the ejecta and filled in the bowl (note the breach in the rim). Its rim crest has been worn down by a multitude of subsequent impacts.

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

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

    Image information: VIS instrument. Latitude 35.9, Longitude 311.1 East (48.9 West). 19 meter/pixel resolution.

  6. Basaltic Crater in Color IR

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released August 6, 2004 This image shows two representations of the same infra-red image near Nili Fosse in the the Isidis region of Mars. On the left is a grayscale image showing surface temperature, and on the right is a false-color composite made from 3 individual THEMIS bands. The false-color image is colorized using a technique called decorrelation stretch (DCS), which emphasizes the spectral differences between the bands to highlight compositional variations. In many cases craters trap sand in their topographic depressions, interrupting the sand's migration across the Martian surface. This image is particularly interesting because there appears to be more than 1 type of sand in the bottom of this crater and in the hummocky terrain near the bottom of the image. The pink/magenta areas are characteristic of a basaltic composition, but there are also orange areas that are likely caused by the presence of andesite. These two compositions, basalt and andesite, are some of the most common found on Mars.

    Image information: IR instrument. Latitude 24, Longitude 80.7 East (297.3 West). 100 meter/pixel resolution.

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

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip

  7. Basaltic Crater in Color IR

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released August 6, 2004 This image shows two representations of the same infra-red image near Nili Fosse in the the Isidis region of Mars. On the left is a grayscale image showing surface temperature, and on the right is a false-color composite made from 3 individual THEMIS bands. The false-color image is colorized using a technique called decorrelation stretch (DCS), which emphasizes the spectral differences between the bands to highlight compositional variations. In many cases craters trap sand in their topographic depressions, interrupting the sand's migration across the Martian surface. This image is particularly interesting because there appears to be more than 1 type of sand in the bottom of this crater and in the hummocky terrain near the bottom of the image. The pink/magenta areas are characteristic of a basaltic composition, but there are also orange areas that are likely caused by the presence of andesite. These two compositions, basalt and andesite, are some of the most common found on Mars.

    Image information: IR instrument. Latitude 24, Longitude 80.7 East (297.3 West). 100 meter/pixel resolution.

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

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip

  8. Sand Sheet on Crater Floor

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    As with yesterday's image, this dune field is located inside a crater, in this case an unnamed crater at 26 degrees North latitude. In this VIS image the dunes are coalescing into a sand sheet, note the lack of dune forms to the north of the small hills. The presence of ridges and hills in the area is affecting the dune shapes.

    Image information: VIS instrument. Latitude 26.4, Longitude 62.7 East (297.3 West). 19 meter/pixel resolution.

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

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

  9. Collapse Pits in Bernard Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    We will be looking at collapse pits for the next two weeks. Collapse pits on Mars are formed in serveral ways. In volcanic areas, channelized lava flows can form roofs which insulate the flowing lava. These features are termed lava tubes on Earth and are common features in basaltic flows. After the lava has drained, parts of the roof of the tube will collapse under its own weight. These collapse pits will only be as deep as the bottom of the original lava tube. Another type of collapse feature associated with volcanic areas arises when very large eruptions completely evacuate the magma chamber beneath the volcano. The weight of the volcano will cause the entire ediface to subside into the void space below it. Structural features including fractures and graben will form during the subsidence. Many times collapse pits will form within the graben. In addition to volcanic collapse pits, Mars has many collapse pits formed when volatiles (such as subsurface ice) are released from the surface layers. As the volatiles leave, the weight of the surrounding rock causes collapse pits to form.

    These pits occur in the floor of Bernard Crater. These collapse pits were likely formed by the release of volatiles from the materials deposited in the crater floor.

    Image information: VIS instrument. Latitude -24, Longitude 205.5 East (154.5 West). 19 meter/pixel resolution.

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

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission

  10. Gale Crater in IR Color

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released August 4, 2004 This image shows two representations of the same infra-red image of Gale Crater. On the left is a grayscale image showing surface temperature, and on the right is a false-color composite made from 3 individual THEMIS bands. The false-color image is colorized using a technique called decorrelation stretch (DCS), which emphasizes the spectral differences between the bands to highlight compositional variations.

    In the bottom of the crater, surrounding the central mound, there are extensive basaltic sand deposits. The basaltic sand spectral signature combined with the warm surface (due to the low albedo of basaltic sand) produces a very strong pink/magenta color. This color signature contrasts with the green/yellow color of soil and dust in the top of the image, and the cyan color due to the presence of water ice clouds at the bottom of the image. This migrating sand may be producing the erosional features seen on the central mound.

    Image information: IR instrument. Latitude -4.4, Longitude 137.4 East (222.6 West). 100 meter/pixel resolution.

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

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University

  11. Impact and cratering rates onto Pluto

    NASA Astrophysics Data System (ADS)

    Greenstreet, Sarah; Gladman, Brett; McKinnon, William B.

    2015-09-01

    The New Horizons spacecraft fly-through of the Pluto system in July 2015 will provide humanity's first data for the crater populations on Pluto and its binary companion, Charon. In principle, these surfaces could be dated in an absolute sense, using the observed surface crater density (# craters/km2 larger than some threshold crater diameter D). Success, however, requires an understanding of both the cratering physics and absolute impactor flux. The Canada-France Ecliptic Plane Survey (CFEPS) L7 synthetic model of classical and resonant Kuiper belt populations (Petit, J.M. et al. [2011]. Astron. J. 142, 131-155; Gladman, B. et al. [2012]. Astron. J. 144, 23-47) and the scattering object model of Kaib et al. (Kaib, N., Roškar, R., Quinn, T. [2011]. Icarus 215, 491-507) calibrated by Shankman et al. (Shankman, C. et al. [2013]. Astrophys. J. 764, L2-L5) provide such impact fluxes and thus current primary cratering rates for each dynamical sub-population. We find that four sub-populations (the q < 42AU hot and stirred main classicals, the classical outers, and the plutinos) dominate Pluto's impact flux, each providing ≈ 15- 25 % of the total rate. Due to the uncertainty in how the well-characterized size distribution for Kuiper belt objects (with impactor diameter d > 100km) connects to smaller projectiles, we compute cratering rates using five model impactor size distributions: a single power-law, a power-law with a knee, a power-law with a divot, as well as the "wavy" size distributions described in Minton et al. (Minton, D.A. et al. [2012]. Asteroids Comets Meteors Conf. 1667, 6348) and Schlichting et al. (Schlichting, H.E., Fuentes, C.I., Trilling, D.E. [2013]. Astron. J. 146, 36-42). We find that there is only a small chance that Pluto has been hit in the past 4 Gyr by even one impactor with a diameter larger than the known break in the projectile size distribution (d ≈ 100km) which would create a basin on Pluto (D ⩾ 400km in diameter). We show that due to

  12. Visual data of minor meteor showers limits of the method

    NASA Technical Reports Server (NTRS)

    Rendtel, Jurgen; Koschack, R.

    1992-01-01

    Visual meteor observations are carried out on a regular basis by many experienced observers worldwide, thus supplying information about activity of meteor showers. The limits of the method are determined by the accuracy of the detection of the meteor trail. This study shows that visual meteor observations provide reliable data for an observable hourly rate of greater than or equal to 3.

  13. The First Confirmed Videorecordings of Lunar Meteor Impacts

    NASA Technical Reports Server (NTRS)

    Dunham, D. W.; Cudnik, B.; Palmer, D. M.; Sada, P. V.; Melosh, J.; Beech, M.; Pellerin, L.; Asher, D.; Frankenberger R.; Venable R.

    2000-01-01

    North American observers recorded at least six meteors striking the Moon's surface during the Leonid meteor shower on 1999 Nov. 18. Each meteor produced a flash that was recorded from at least two separate locations, marking the first confirmed lunar meteor impacts.

  14. Calibrating Video Cameras For Meteor Works

    NASA Astrophysics Data System (ADS)

    Khaleghy-Rad, Mona; Campbell-Brown, M.

    2006-09-01

    The calculation of the intensity of light produced by a meteor ablating in the atmosphere is crucial to determination of meteoroid masses, and to uncovering the meteoroid's physical structure through ablation modeling. A necessary step in the determination is to use cameras which have been end-to-end calibrated to determine their precise spectral response. We report here a new procedure for calibrating low-light video cameras used for meteor observing, which will be used in conjunction with average meteor spectra to determine absolute light intensities.

  15. Radio Meteors Observations Techniques at RI NAO

    NASA Astrophysics Data System (ADS)

    Vovk, Vasyl; Kaliuzhnyi, Mykola

    2016-07-01

    The Solar system is inhabited with large number of celestial bodies. Some of them are well studied, such as planets and vast majority of big asteroids and comets. There is one group of objects which has received little attention. That is meteoroids with related to them meteors. Nowadays enough low-technology high-efficiency radio-technical solutions are appeared which allow to observe meteors daily. At RI NAO three methodologies for meteor observation are developed: single-station method using FM-receiver, correlation method using FM-receiver and Internet resources, and single-station method using low-cost SDR-receiver.

  16. The 2014 May Camelopardalid Meteor Shower

    NASA Technical Reports Server (NTRS)

    Cooke, Bill; Moser, Danielle

    2014-01-01

    On May 24, 2014 Earth will encounter multiple streams of debris laid down by Comet 209P LINEAR. This will likely produce a new meteor shower, never before seen. Rates predicted to be from 100 to 1000 meteors per hour between 2 and 4 AM EDT, so we are dealing with a meteor outburst, potentially a storm. Peak rate of 200 per hour best current estimate. Difficult to calibrate models due to lack of past observations. Models indicate mm size particles in stream, so potential risk to Earth orbiting spacecraft.

  17. Investigating the effects of target heterogeneity on the cratering process.

    NASA Astrophysics Data System (ADS)

    Barnouin, O. S.

    2012-12-01

    Pre-existing target structures are known to influence the dynamics and morphologies of many terrestrial and planetary impact craters. Good examples include the Chesapeake and Ries craters, which both possess an inverted sombrero structure as a result of a weaker sedimentary surface layer overlying a stronger crystalline basement. But beyond such horizontal layering, closer analyses of the subsurface geology present in these and other planetary craters indicate that vertical heterogeneity in the strength and geochemistry of a target are also often present. These may influence the formation and subsequent modification of terrestrial craters. Evidence indicates that at Meteor crater, for example, pre-existing vertical jointing of the target gives this crater its square appearance, either by confining and re-directing the shock and subsequent rarefraction waves, or by allowing preferential weathering zones of weakness along the joints. In this study, we present a series of laboratory investigations and 2- and 3-dimensional numerical calculations of crater formation in a conceptually simple but physically complex target: a box of randomly distributed quartz spheres of identical size. These investigations provide constraints on how all types of target heterogeneity influence the cratering process. In both the laboratory and numerical studies, we measure the rate of crater growth, the transient crater shape, and in some instances the velocity of individual ejecta. These investigations vary the ratio of the impact shock thickness to target grain size by altering the impact velocity, projectile size, and target grain size. The laboratory data were collected at the NASA Ames vertical gun range, the NASA Johnson Space Center vertical gun range, and the University of Tokyo vertical gun range using non-intrusive diagonistic techniques. The numerical investigations were performed using the CTH hydrocode that solves the equations of motion, while conserving mass, energy, and

  18. Impact Crater with Smoothed Rim

    NASA Image and Video Library

    2012-03-01

    This image from NASA Dawn spacecraft of asteroid Vesta shows hows a large impact crater whose rim is rather smoothed and degraded. There are many smaller, younger craters surrounding and inside of this crater and these have sharper, fresher rims.

  19. Shirakatsi Crater on the Moon

    NASA Astrophysics Data System (ADS)

    Harutyunyan, G. S.

    2014-10-01

    One of the Moon's craters is named after Anania Shirakatsi. It was named due to Viktor Ambartsumian's application to the International Astronomical Union. The crater has 51km diameter and is coupled with the neighboring crater Dobrovolski.

  20. Physical and dynamical studies of meteors. Meteor-fragmentation and stream-distribution studies

    NASA Technical Reports Server (NTRS)

    Sekanina, Z.; Southworth, R. B.

    1975-01-01

    Population parameters of 275 streams including 20 additional streams in the synoptic-year sample were found by a computer technique. Some 16 percent of the sample is in these streams. Four meteor streams that have close orbital resemblance to Adonis cannot be positively identified as meteors ejected by Adonis within the last 12000 years. Ceplecha's discrete levels of meteor height are not evident in radar meteors. The spread of meteoroid fragments along their common trajectory was computed for most of the observed radar meteors. There is an unexpected relationship between spread and velocity that perhaps conceals relationships between fragmentation and orbits; a theoretical treatment will be necessary to resolve these relationships. Revised unbiased statistics of synoptic-year orbits are presented, together with parallel statistics for the 1961 to 1965 radar meteor orbits.

  1. Video meteor detection filtering using soft computing methods

    NASA Astrophysics Data System (ADS)

    Silađi, E.; Vida, D.; Nyarko, K.

    2015-01-01

    In this paper we present the current progress and results from the filtering of Croatian Meteor Network video meteor detections using soft computing methods such as neural networks and support vector machines (SVMs). The goal is to minimize the number of false-positives while preserving the real meteor detections. This is achieved by pre-processing the data to extract meteor movement parameters and then recognizing patterns distinct to meteors. The input data format is fully compliant with the CAMS meteor data standard, and as such the proposed method could be utilized by other meteor networks of the similar kind.

  2. Effects of meteoric debris on stratospheric aerosols and gases

    NASA Technical Reports Server (NTRS)

    Turco, R. P.; Toon, O. B.; Whitten, R. C.; Hamill, P.

    1981-01-01

    Characterizations of meteoric dust height and size distributions are obtained using Hunten's calculations of meteor ablation and recondensation rates. The contribution of meteor residues to aerosol composition, the role of meteoric dust as condensation nuclei, and the effects of meteor debris on aerosol size distributions are quantified, and particle surface areas are estimated. The potential importance of heterogeneous chemistry for stratospheric trace gases is discussed. The interaction between H2SO4 vapor and meteor metal vapors is investigated. It is concluded that meteoric particles may dominate the natural stratospheric aerosols at small (less than .01 micron radius) and large (greater than 1 micron radius) sizes under normal conditions.

  3. Cove, Arizona Mines: Factsheets

    EPA Pesticide Factsheets

    This factsheet contains information about planned construction activities to mitigate surface erosion at the former transfer area located in the Cove/Red Valley Chapter of the Navajo Nation in eastern Arizona.

  4. Clayheads in Arizona.

    ERIC Educational Resources Information Center

    Schubert, Thorne Erwin

    1990-01-01

    Describes how junior high school students in Arizona combine what they have learned in ceramic history class with ceramic production skills to create their own personal ceramic heads in their images. (KM)

  5. Clayheads in Arizona.

    ERIC Educational Resources Information Center

    Schubert, Thorne Erwin

    1990-01-01

    Describes how junior high school students in Arizona combine what they have learned in ceramic history class with ceramic production skills to create their own personal ceramic heads in their images. (KM)

  6. Northern Arizona Volcanoes

    NASA Image and Video Library

    2006-05-01

    Northern Arizona is best known for the Grand Canyon. Less widely known are the hundreds of geologically young volcanoes, at least one of which buried the homes of local residents. This image was acquired by NASA Terra spacecraft.

  7. Crater in the Mangala Valles Region

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 26 May 2003

    Just south of the 2 km high main mass of the Medusae Fossae Formation, in a region dissected by channels, lies an unnamed crater that may have been filled by mud. A channel spills into this crater on its eastern side and may have delivered the material that now covers the floor of the crater. The subdued ridges may be wrinkle ridges in a preexisting lava flow that are now covered by a layer of sediment. The cracked surface is evidence for the subsequent deposition of mud.

    Image information: VIS instrument. Latitude -6, Longitude 206.7 East (153.3 West). 19 meter/pixel resolution.

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

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

  8. Effects of Pre-Existing Target Structure on the Formation of Large Craters

    NASA Technical Reports Server (NTRS)

    Barnouin-Jha, O. S.; Cintala, M. J.; Crawford, D. A.

    2003-01-01

    The shapes of large-scale craters and the mechanics responsible for melt generation are influenced by broad and small-scale structures present in a target prior to impact. For example, well-developed systems of fractures often create craters that appear square in outline, good examples being Meteor Crater, AZ and the square craters of 433 Eros. Pre-broken target material also affects melt generation. Kieffer has shown how the shock wave generated in Coconino sandstone at Meteor crater created reverberations which, in combination with the natural target heterogeneity present, created peaks and troughs in pressure and compressed density as individual grains collided to produce a range of shock mineralogies and melts within neighboring samples. In this study, we further explore how pre-existing target structure influences various aspects of the cratering process. We combine experimental and numerical techniques to explore the connection between the scales of the impact generated shock wave and the pre-existing target structure. We focus on the propagation of shock waves in coarse, granular media, emphasizing its consequences on excavation, crater growth, ejecta production, cratering efficiency, melt generation, and crater shape. As a baseline, we present a first series of results for idealized targets where the particles are all identical in size and possess the same shock impedance. We will also present a few results, whereby we increase the complexities of the target properties by varying the grain size, strength, impedance and frictional properties. In addition, we investigate the origin and implications of reverberations that are created by the presence of physical and chemical heterogeneity in a target.

  9. Meteor shower activity derived from meteor watching public campaign in Japan

    NASA Astrophysics Data System (ADS)

    Ishizaki, Masaharu; Watanabe, Jun-ichi; Sato, Mikiya

    2017-09-01

    We have carried out a meteor watching public campaigns from 2004 for major meteor showers in the case of appropriate observing condition as one of the outreach programs conducted by National Astronomical Observatory of Japan. We received a huge number of the reports on meteor counts from the general public participants. The results sometimes show similar time variation of the hourly rates derived from the data collected by skilled observers. In this paper, some of the results are presented showing that such campaigns have a potential to extract scientific result related to the meteor showers mainly due to the large number of the data collected by unskilled observers.

  10. The KUT meteor radar: An educational low cost meteor observation system by radio forward scattering

    NASA Astrophysics Data System (ADS)

    Madkour, W.; Yamamoto, M.

    2016-01-01

    The Kochi University of Technology (KUT) meteor radar is an educational low cost observation system built at Kochi, Japan by successive graduate students since 2004. The system takes advantage of the continuous VHF- band beacon signal emitted from Fukui National College of Technology (FNCT) for scientific usage all over Japan by receiving the forward scattered signals. The system uses the classical forward scattering setup similar to the setup described by the international meteor organization (IMO), gradually developed from the most basic single antenna setup to the multi-site meteor path determination setup. The primary objective is to automate the observation of the meteor parameters continuously to provide amounts of data sufficient for statistical analysis. The developed software system automates the observation of the astronomical meteor parameters such as meteor direction, velocity and trajectory. Also, automated counting of meteor echoes and their durations are used to observe mesospheric ozone concentration by analyzing the duration distribution of different meteor showers. The meteor parameters observed and the methodology used for each are briefly summarized.

  11. Precise Orbit Determination of Meteors by HPLA Radar and the MU Radar Meteor Head Echo Database

    NASA Astrophysics Data System (ADS)

    Nakamura, Takuji; Yamamoto, Mamoru; Tanaka, Yoshi; Kero, Johan; Szasz, Csilla; Watanabe, Juniichi; Abe, Shinsuke; Kastinen, Daniel

    Mass influx from the space into the terrestrial atmosphere is mainly caused by meteors. Meteors delivers various elements into the atmosphere, but the meteoric dust particles are also of great importance in the terrestrial atmosphere, as they act as nucleus for condensation and clouds and affect various atmospheric phenomena both in physical and chemical aspects. Thus, to investigate the meteor flux, orbits and their interactions in the upper atmosphere is very important but at the same time the method of investigation is limited, especially for the precise measurements High power large aperture (HPLA) radar observation is a recent technique to provide useful information on meteor influx and orbits, as well as interactions with the atmosphere. The recent development of the technique carried out using the middle and upper atmosphere radar (MU radar) of Kyoto University at Shigaraki (34.9N, 136.1S), which is a large atmospheric VHF radar with 46.5 MHz frequency, 1 MW output transmission power and 8330 m2 aperture array antenna, has established very precise orbit observations from meteor head echoes. Since 2009, orbital data of about 120,000 meteors have been collected. An open database (MU radar meteor head echo database: MURMHED) for research and education is now being created. In this study, we present the physical quantities and precisions obtained from the MU radar meteor head echo observations and the details of the open database.

  12. Meteor radar response function: Application to the interpretation of meteor backscatter at medium frequency

    NASA Astrophysics Data System (ADS)

    Cervera, M. A.; Holdsworth, D. A.; Reid, I. M.; Tsutsumi, M.

    2004-11-01

    Recently, Cervera and Elford (2004) extended earlier work on the development of the meteor radar response function (Elford, 1964; Thomas et al., 1988) to include a nonuniform meteor ionization profile. This approach has the advantage that the height distribution of meteors expected to be observed by a radar meteor system is able to be accurately modeled and insights into the meteoroid chemistry to be gained. The meteor radar response function is also an important tool with regard to the interpretation of meteor backscatter in other areas, e.g., modeling the expected diurnal variation of sporadic meteors, investigating the expected echo distribution over the sky, and the calculation of the expected rate curves of meteor showers. We exemplify each of these techniques from the analysis of meteor data collected by the Buckland Park 2 MHz system during October 1997. In addition, we show that the response function may be used to quantify the echo rate of a given shower relative to the sporadic background and thus determine if that shower is able to be detected by the radar.

  13. Reuyl Crater Dust Avalanches

    NASA Image and Video Library

    2002-06-04

    The rugged, arcuate rim of the 90 km crater Reuyl dominates this NASA Mars Odyssey image. Reuyl crater is at the southern edge of a region known to be blanketed in thick dust based on its high albedo brightness and low thermal inertia values.

  14. Gale Crater Mound

    NASA Image and Video Library

    2003-03-27

    The eroded, layered deposit in this NASA Mars Odyssey image of Gale Crater is a mound of material rising 3 km about 2 miles above the crater floor. It has been sculpted by wind and possibly water to produce the dramatic landforms seen today.

  15. Proctor Crater Dune Field

    NASA Image and Video Library

    2010-11-16

    This observation from NASA Mars Reconnaissance Orbiter shows the edge of a dark dune field on the floor of Proctor Crater in the Southern highlands of Mars. The dark dunes are composed of basaltic sand that has collected on the bottom of the crater.

  16. 'Endurance Crater' Overview

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This overview of 'Endurance Crater' traces the path of the Mars Exploration Rover Opportunity from sol 94 (April 29, 2004) to sol 205 (August 21, 2004). The route charted to enter the crater was a bit circuitous, but well worth the extra care engineers took to ensure the rover's safety. On sol 94, Opportunity sat on the edge of this impressive, football field-sized crater while rover team members assessed the scene. After traversing around the 'Karatepe' region and past 'Burns Cliff,' the rover engineering team assessed the possibility of entering the crater. Careful analysis of the angles Opportunity would face, including testing an Earth-bound model on simulated martian terrain, led the team to decide against entering the crater at that particular place. Opportunity then backed up before finally dipping into the crater on its 130th sol (June 5, 2004). The rover has since made its way down the crater's inner slope, grinding, trenching and examining fascinating rocks and soil targets along the way. The rover nearly made it to the intriguing dunes at the bottom of the crater, but when it got close, the terrain did not look safe enough to cross.

  17. Fresh Copernican Crater

    NASA Image and Video Library

    2009-12-21

    A subset of NAC Image M112162602L showing landslides bottom covering impact melt on the floor top of a fresh Copernican-age crater at the edge of Oceanus Procellarum and west of Balboa crater taken by NASA Lunar Reconnaissance Orbiter.

  18. Dunes in Herschel Crater

    NASA Image and Video Library

    2010-10-14

    This image from NASA Mars Reconnaissance Orbiter shows dunes on the floor of Herschel Crater. Steep faces lipfaces are oriented downwind, in the direction of motion of the dunes. A dune-free area downwind of the crater is seen at the image center.

  19. Venus - Mead Crater

    NASA Image and Video Library

    1996-02-07

    NASA's Magellan image mosaic shows the largest impact crater known to exist on Venus at this point in the Magellan mission. The crater is located north of Aphrodite Terra and east of Eistla Regio and was imaged during orbit 804 on November 12, 1990. http://photojournal.jpl.nasa.gov/catalog/PIA00148

  20. Topography of Gale Crater

    NASA Image and Video Library

    2011-11-21

    Color coding in this image of Gale Crater on Mars represents differences in elevation. The vertical difference from a low point inside the landing ellipse for NASA Mars Science Laboratory yellow dot to a high point on the mountain inside the crater.

  1. Meteor Shower Forecasting for Spacecraft Operations

    NASA Technical Reports Server (NTRS)

    Moorhead, Althea V.; Cooke, William J.; Campbell-Brown, Margaret D.

    2017-01-01

    Although sporadic meteoroids generally pose a much greater hazard to spacecraft than shower meteoroids, meteor showers can significantly increase the risk of damage over short time periods. Because showers are brief, it is sometimes possible to mitigate the risk operationally, which requires accurate predictions of shower activity. NASA's Meteoroid Environment Office (MEO) generates an annual meteor shower forecast that describes the variations in the near-Earth meteoroid flux produced by meteor showers, and presents the shower flux both in absolute terms and relative to the sporadic flux. The shower forecast incorporates model predictions of annual variations in shower activity and quotes fluxes to several limiting particle kinetic energies. In this work, we describe our forecasting methods and present recent improvements to the temporal profiles based on flux measurements from the Canadian Meteor Orbit Radar (CMOR).

  2. Meteor Shower Forecasting for Spacecraft Operations

    NASA Technical Reports Server (NTRS)

    Moorhead, Althea V.; Cooke, William J.; Campbell-Brown, Margaret D.

    2017-01-01

    Although sporadic meteoroids are a much greater hazard to spacecraft than shower meteoroids in general, meteor showers can significantly increase the risk of damage over short time periods. Because showers are brief, it is sometimes possible to mitigate the risk operationally, which requires accurate predictions of shower activity. NASA's Meteoroid Environment Office generates an annual meteor shower forecast that describes the variations in the near-Earth meteoroid flux produced by meteor showers, which presents the shower flux both in absolute terms and relative to the sporadic ux. The shower forecast incorporates model predictions of annual variations in shower activity and quotes fluxes to several limiting particle kinetic energies. In this work, we describe our forecasting methods, compare them to actual observations, and highlight recent improvements to the temporal pro les based on flux measurements from the Canadian Meteor Orbit Radar (CMOR).

  3. Meteor showers associated with 2003EH1

    NASA Astrophysics Data System (ADS)

    Babadzhanov, P. B.; Williams, I. P.; Kokhirova, G. I.

    2008-06-01

    Using the Everhart RADAU19 numerical integration method, the orbital evolution of the near-Earth asteroid 2003EH1 is investigated. This asteroid belongs to the Amor group and is moving on a comet-like orbit. The integrations are performed over one cycle of variation of the perihelion argument ω. Over such a cycle, the orbit intersect that of the Earth at eight different values of ω. The orbital parameters are different at each of these intersections and so a meteoroid stream surrounding such an orbit can produce eight different meteor showers, one at each crossing. The geocentric radiants and velocities of the eight theoretical meteor showers associated with these crossing points are determined. Using published data, observed meteor showers are identified with each of the theoretically predicted showers. The character of the orbit and the existence of observed meteor showers associated with 2003EH1 confirm the supposition that this object is an extinct comet.

  4. SAGE III/Meteor - 3M

    NASA Technical Reports Server (NTRS)

    1999-01-01

    From left to right: Richard Rawls, Chip Holloway, and Art Hayhurst standing next to the Stratospheric Aerosol Gastropheric Experiment (SAGE)/Meteor - 3M flight instrument. Photographed in building 1250, 40 foot clean room.

  5. SAGE III/Meteor - 3M

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Back view of the SAGE III Bench Checkout Unit, Portable Image Generator (PIG) on tripod, and the Stratospheric Aerosol Gastropheric Experiment (SAGE)/Meteor - 3M flight instrument. Photographed in building 1250, 40 foot clean room.

  6. SAGE III/Meteor - 3M

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Full view of the SAGE III Bench Checkout Unit, Collimated Source Bench (CSB), Portable Image Generator (PIG) on tripod, and Stratospheric Aerosol Gastropheric Experiment (SAGE)/Meteor - 3M flight instrument. Photographed in building 1250, 40 foot clean room.

  7. The archiving of meteor research information

    NASA Technical Reports Server (NTRS)

    Nechitailenko, V. A.

    1987-01-01

    The results obtained over the past years under GLOBMET are not reviewed but some of the problems the solution of which will guide further development of meteor investigation and international cooperation in this field for the near term are discussed. The main attention is paid to problems which the meteor community itself can solve, or at least expedite. Most of them are more or less connected with the problem of information archiving. Information archiving deals with methods and techniques of solving two closely connected groups of problems. The first is the analysis of data and information as an integral part of meteor research and deals with the solution of certain methodological problems. The second deals with gathering data and information for the designing of models of the atmosphere and/or meteor complex and its utilization. These problem solutions are discussed.

  8. Large Meteor Tracked over Northeast Alabama

    NASA Image and Video Library

    On the evening of May 18, NASA all-sky meteor cameras located at NASA’s Marshall Space Flight Center and at the Walker County Science Center near Chickamauga, Ga. tracked the entry of a large meteo...

  9. Man-Sized Meteor Over Macon

    NASA Image and Video Library

    Astronomers at NASA's Marshall Space Flight Center have recorded the brightest meteor ever seen by their network. On May 20, 2011, six-foot diameter fragment of an unknown comet entered the atmosph...

  10. Monte Carlo modeling and meteor showers

    NASA Technical Reports Server (NTRS)

    Kulikova, N. V.

    1987-01-01

    Prediction of short lived increases in the cosmic dust influx, the concentration in lower thermosphere of atoms and ions of meteor origin and the determination of the frequency of micrometeor impacts on spacecraft are all of scientific and practical interest and all require adequate models of meteor showers at an early stage of their existence. A Monte Carlo model of meteor matter ejection from a parent body at any point of space was worked out by other researchers. This scheme is described. According to the scheme, the formation of ten well known meteor streams was simulated and the possibility of genetic affinity of each of them with the most probable parent comet was analyzed. Some of the results are presented.

  11. ScienceCast 31: Draconid Meteor Outburst

    NASA Image and Video Library

    2011-10-05

    Forecasters say Earth is heading for a stream of dust from Comet 21P/Giacobini-Zinner. A close encounter with the comet's fragile debris could spark a meteor outburst over parts of our planet on October 8th.

  12. Comparison with Russian analyses of meteor impact

    SciTech Connect

    Canavan, G.H.

    1997-06-01

    The inversion model for meteor impacts is used to discuss Russian analyses and compare principal results. For common input parameters, the models produce consistent estimates of impactor parameters. Directions for future research are discussed and prioritized.

  13. Bigger Crater Farther South of 'Victoria' on Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Annotated version

    The team operating NASA's Mars Exploration Rover Opportunity has chosen southeast as the direction for the rover's next extended journey, toward a crater more than 20 times wider than 'Victoria Crater.' Opportunity exited Victoria Crater on Aug. 28, 2008, after nearly a year investigating the interior.

    The crater to the southeast is about 22 kilometers (13.7 miles) in diameter and about 300 meters (1,000 feet) deep, exposing a much thicker stack of rock layers than those examined in Victoria Crater.

    The rover team informally calls the bigger crater 'Endeavour' and emphasizes that Opportunity may well never reach it. The rover has already operated more than 18 times longer than originally planned, and the distance to the big crater, about 12 kilometers (7 miles) matches the total distance Opportunity has driven since landing in early 2004. Driving southeastward is expected to take Opportunity to exposures of younger rock layers than is has previously seen and to provide access to rocks on the plain that were thrown long distances by impacts that excavated even deeper, more distant craters.

    The crater that Opportunity will drive toward dominates this orbital view from the Thermal Emission Imaging System (THEMIS) camera on NASA's Mars Odyssey orbiter. The much smaller Victoria Crater is the most prominent circle near the upper left corner of the image. This view is a mosaic of about 50 separate visible-light images taken by THEMIS.

    NASA's Jet Propulsion Laboratory manages the Mars Odyssey and Mars Exploration Rover missions for the NASA Science Mission Directorate, Washington, D.C. THEMIS was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the

  14. Analysis of ALTAIR 1998 Meteor Radar Data

    NASA Technical Reports Server (NTRS)

    Zinn, J.; Close, S.; Colestock, P. L.; MacDonell, A.; Loveland, R.

    2011-01-01

    We describe a new analysis of a set of 32 UHF meteor radar traces recorded with the 422 MHz ALTAIR radar facility in November 1998. Emphasis is on the velocity measurements, and on inferences that can be drawn from them regarding the meteor masses and mass densities. We find that the velocity vs altitude data can be fitted as quadratic functions of the path integrals of the atmospheric densities vs distance, and deceleration rates derived from those fits all show the expected behavior of increasing with decreasing altitude. We also describe a computer model of the coupled processes of collisional heating, radiative cooling, evaporative cooling and ablation, and deceleration - for meteors composed of defined mixtures of mineral constituents. For each of the cases in the data set we ran the model starting with the measured initial velocity and trajectory inclination, and with various trial values of the quantity mPs 2 (the initial mass times the mass density squared), and then compared the computed deceleration vs altitude curves vs the measured ones. In this way we arrived at the best-fit values of the mPs 2 for each of the measured meteor traces. Then further, assuming various trial values of the density Ps, we compared the computed mass vs altitude curves with similar curves for the same set of meteors determined previously from the measured radar cross sections and an electrostatic scattering model. In this way we arrived at estimates of the best-fit mass densities Ps for each of the cases. Keywords meteor ALTAIR radar analysis 1 Introduction This paper describes a new analysis of a set of 422 MHz meteor scatter radar data recorded with the ALTAIR High-Power-Large-Aperture radar facility at Kwajalein Atoll on 18 November 1998. The exceptional accuracy/precision of the ALTAIR tracking data allow us to determine quite accurate meteor trajectories, velocities and deceleration rates. The measurements and velocity/deceleration data analysis are described in Sections

  15. Centrifuge Impact Cratering Experiments

    NASA Technical Reports Server (NTRS)

    Schmidt, R. M.; Housen, K. R.; Bjorkman, M. D.

    1985-01-01

    The kinematics of crater growth, impact induced target flow fields and the generation of impact melt were determined. The feasibility of using scaling relationships for impact melt and crater dimensions to determine impactor size and velocity was studied. It is concluded that a coupling parameter determines both the quantity of melt and the crater dimensions for impact velocities greater than 10km/s. As a result impactor radius, a, or velocity, U cannot be determined individually, but only as a product in the form of a coupling parameter, delta U micron. The melt volume and crater volume scaling relations were applied to Brent crater. The transport of melt and the validity of the melt volume scaling relations are examined.

  16. Occator Crater in Perspective

    NASA Image and Video Library

    2015-12-09

    An image of Occator Crater draped over a digital terrain model provides a 3-D-like perspective view of the impact structure. Several bright areas can be seen in this crater. The inner part of the crater forms a type of "crater within a crater" measuring about 6 miles (10 kilometers) in diameter and 0.3 miles (0.5 miles) in depth, and contains the brightest material on all of Ceres. Occator measures about 60 miles (90 kilometers) wide. With its sharp rim and walls, and abundant terraces and landslide deposits, Occator appears to be among the youngest features on Ceres. Dawn mission scientists estimate its age to be about 78 million years old. http://photojournal.jpl.nasa.gov/catalog/PIA20179

  17. Pedestal Crater Development

    NASA Image and Video Library

    2015-07-01

    In this image, we see an approximately 500-meter crater that is fairly fresh (in geological terms), but the ejecta is already high-standing. Could this be an indication of early stage of pedestal development? A pedestal crater is when the ejecta from an impact settles around the new crater and is more erosion-resistant than the surrounding terrain. Over time, the surrounding terrain erodes much faster than the ejecta; in fact, some pedestal craters are measured to be hundreds of meters above the surrounding area. HiRISE has imaged many other pedestal craters before, and the ejecta isn't always symmetrical, as in this observation. http://photojournal.jpl.nasa.gov/catalog/PIA19849

  18. 10Be content in clasts from fallout suevitic breccia in drill cores from the Bosumtwi impact crater, Ghana: Clues to preimpact target distribution

    NASA Astrophysics Data System (ADS)

    Losiak, Anna; Wild, Eva Maria; Michlmayr, Leonard; Koeberl, Christian

    2014-03-01

    Rocks from drill cores LB-07A (crater fill) and LB-08A (central uplift) into the Bosumtwi impact crater, Ghana, were analyzed for the presence of the cosmogenic radionuclide 10Be. The aim of the study was to determine the extent to which target rocks of various depths were mixed during the formation of the crater-filling breccia, and also to detect meteoric water infiltration within the impactite layer. 10Be abundances above background were found in two (out of 24) samples from the LB-07A core, and in none of five samples from the LB-08A core. After excluding other possible explanations for an elevated 10Be signal, we conclude that it is most probably due to a preimpact origin of those clasts from target rocks close to the surface. Our results suggest that in-crater breccias were well mixed during the impact cratering process. In addition, the lack of a 10Be signal within the rocks located very close to the lake sediment-impactite boundary suggests that infiltration of meteoric water below the postimpact crater floor was limited. This may suggest that the infiltration of the meteoric water within the crater takes place not through the aerial pore-space, but rather through a localized system of fractures.

  19. Yalode Crater on Ceres

    NASA Image and Video Library

    2017-06-28

    Yalode crater is so large -- at 162 miles, 260 kilometers in diameter -- that a variety of vantage points is necessary to understand its geological context. This view of the northern portion of Yalode is one of many images NASA's Dawn spacecraft has taken of this crater. The large impact that formed the crater likely involved a lot of heat, which explains the relatively smooth crater floor punctuated by smaller craters. A couple of larger craters in Yalode have polygonal shapes. This type of crater shape is frequently found on Ceres and may be indicative of extensive underground fractures. The larger crater to the right of center in this image is called Lono (12 miles, 20 kilometers in diameter) and the one below it is called Besua (11 miles, 17 kilometers). Some of the small craters are accompanied by ejecta blankets that are more reflective than their surroundings. The strange Nar Sulcus fractures can be seen in the bottom left corner of the picture. Linear features seen throughout the image may have formed when material collapsed above empty spaces underground. These linear features include linear chains of craters called catenae. Dawn took this image on September 27, 2015, from 915 miles (1,470 kilometers) altitude. The center coordinates of this image are 32 degrees south latitude and 300 degrees east longitude. Yalode gets its name from a goddess worshipped by women at the harvest rites in the Dahomey culture of western Africa. Besua takes its name from the Egyptian grain god, and Lono from the Hawaiian god of agriculture. https://photojournal.jpl.nasa.gov/catalog/PIA21410

  20. Meteor showers of the southern hemisphere

    NASA Astrophysics Data System (ADS)

    Molau, Sirko; Kerr, Steve

    2014-04-01

    We present the results of an exhaustive meteor shower search in the southern hemisphere. The underlying data set is a subset of the IMO Video Meteor Database comprising 50,000 single station meteors obtained by three Australian cameras between 2001 and 2012. The detection technique was similar to previous single station analysis. In the data set we find 4 major and 6 minor northern hemisphere meteor showers, and 12 segments of the Antihelion source (including the Northern and Southern Taurids and six streams from the MDC working list). We present details for 14 southern hemisphere showers plus the Centaurid and Puppid-Velid complex, with the η Aquariids and the Southern δ Aquariids being the strongest southern showers. Two of the showers (θ^2 Sagittariids and τ Cetids) were previously unknown and have received preliminary designations by the MDC. Overall we find that the fraction of southern meteor showers south of -30deg declination (roughly 25%) is clearly smaller than the fraction of northern meteor showers north of +30deg declination (more than 50%) obtained in our previous analysis.

  1. Eagle Crater Traverse Area

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image shows an overhead view of the Mars Exploration Rover Opportunity landing site at Meridiani Planum, nicknamed 'Eagle Crater.' Scientists are conducting a soil survey here to see how the soils in this crater relate to the soils near the Meridiani Planum rock outcrop, as well as on the plains outside the crater. Scientists have studied the soils in great detail on the north and west sides of the crater, and plan to study five more locations before Opportunity exits the crater. As of sol 54 of Opportunity's journey (March 18, 2004), the rover is stationed at the sol 53 stop, located in the bottom right quadrant of this image. Scientists are examining light and dark soil targets at this spot, dubbed 'Neopolitan' because it is a triple boundary between light soil, dark soil, and an airbag bounce mark.

    This 3-D visualization was displayed using software developed by NASA's Ames Research Center and images from Opportunity's panoramic camera, taken while the rover was still on the lander.

    [figure removed for brevity, see original site] Figure 1

    Eagle Crater Traverse Map Figure 1 shows an overhead view of the Mars Exploration Rover Opportunity landing site at Meridiani Planum, nicknamed 'Eagle Crater.' Scientists are conducting a soil survey here to see how the soils in this crater relate to the soils by the Meridiani Planum rock outcrop, as well as on the plains outside the crater. They have studied the soils in great detail on the north and west sides of the crater. Locations within the crater where scientists have taken microscopic images of the soil are shown in blue.

    [figure removed for brevity, see original site] Figure 2

    Sampling 'Eagle Crater' Scientists have studied five unique target soil patches on the south and east sides of the crater using the microscopic imager and Moessbauer spectrometer. 'Goal 5' is a wind-rippled spot on the upper part of the crater, which the miniature thermal emission spectrometer shows is

  2. 'Mazatzal' Rock on Crater Rim

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Spirit took this navigation camera image of the 2-meter-wide (6.6-foot-wide) rock called 'Mazatzal' on sol 76, March 21, 2004. Scientists intend to aggressively analyze this target with Spirit's microscopic imager, Moessbauer spectrometer and alpha particle X-ray spectrometer before brushing and 'digging in' with the rock abrasion tool on upcoming sols.

    Mazatzal stood out to scientists because of its large size, light tone and sugary surface texture. It is the largest rock the team has seen at the rim of the crater informally named 'Bonneville.' It is lighter-toned than previous rock targets Adirondack and Humphrey. Its scalloped pattern may be a result of wind sculpting, a very slow process in which wind-transported silt and sand abrade the rock's surface, creating depressions. This leads scientists to believe that Mazatzal may have been exposed to the wind in this location for an extremely long time.

    The name 'Mazatzal' comes from a mountain range and rock formation that was deposited around 1.2 billion years ago in the Four Peaks area of Arizona.

  3. January and February Meteor Showers Detected by CAMS: the Cameras for Allsky Meteor Surveillance

    NASA Astrophysics Data System (ADS)

    Johnson, Beth; Jenniskens, P. M.

    2014-01-01

    Many meteor showers are in need of validation. Of 493 meteor showers listed in the IAU Working List of Mete-or Showers, only 95 are established. Of the rest, it is uncertain whether they exist or not. The goal of the Cameras for Allsky Meteor Surveillance (CAMS) project in California is to validate or remove the remaining 325 showers. CAMS scales up the use of low-light-level video for meteor triangulation, by deploying 60 video cameras spread over three sites. Once the video data has been analyzed, showers can be confirmed by comparing arrival time, direc-tion of the radiant, and speed of the individual meteors. Once established, showers can be linked to their parent bod-ies and meteoroid streams. The CAMS stations are located in Sunnyvale, at Fremont Peak Observatory, and at Lick Observatory, to the south and east of Sunnyvale, respectively. Each station contains 20 low-light-level security cameras arrayed to view the entire sky above 30°. During the night, the video data from the cameras is written to disk and analysed in day-time with the MeteorScan software package to find moving objects. Eight-second video sequences are saved for all detections. The video sequences are combined at the SETI Institute, where astrometric calibration files are generated and meteors detected from at least two stations simultaneously are found interactively using the Coincidence program. Coincidence also calculates the radiant and velocity of each meteor. Here, we discuss results obtained in January and February 2013. Over 7,500 meteor orbits were cataloged in this period. This outcome doubled the detection rate from the previous two years of CAMS data.We will present graphs of the detected meteor showers and discuss their parent body sources.

  4. Meteoric Ions in Planetary Ionospheres

    NASA Technical Reports Server (NTRS)

    Pesnell, W. D.; Grebowsky, Joseph M.; Vondrak, Richard R. (Technical Monitor)

    2001-01-01

    Solar system debris, in the form of meteoroids, impacts every planet. The flux, relative composition and speed of the debris at each planet depends on the planet's size and location in the solar system. Ablation in the atmosphere evaporates the meteoric material and leaves behind metal atoms. During the ablation process metallic ions are formed by impact ionization. For small inner solar system planets, including Earth, this source of ionization is typically small compared to either photoionization or charge exchange with ambient molecular ions. For Earth, the atmosphere above the main deposition region absorbs the spectral lines capable of ionizing the major metallic atoms (Fe and Mg) so that charge exchange with ambient ions is the dominant source. Within the carbon dioxide atmosphere of Mars (and possibly Venus), photoionization is important in determining the ion density. For a heavy planet like Jupiter, far from the sun, impact ionization of ablated neutral atoms by impacts with molecules becomes a prominent source of ionization due to the gravitational acceleration to high incident speeds. We will describe the processes and location and extent of metal ion layers for Mars, Earth and Jupiter, concentrating on flagging the uncertainties in the models at the present time. This is an important problem, because low altitude ionosphere layers for the planets, particularly at night, probably consist predominantly of metallic ions. Comparisons with Earth will be used to illustrate the differing processes in the three planetary atmospheres.

  5. Results of Lunar Impact Observations During Geminid Meteor Shower Events

    NASA Technical Reports Server (NTRS)

    Suggs, R. J.; Suggs, R. M.

    2015-01-01

    Meteoroids are natural particles with origins from comets, asteroids, and planets from within the solar system. On average, 33 metric tons (73,000 lb) of meteoroids hit Earth everyday with velocities ranging between 20 and 72 km/s. However, the vast majority of these meteoroids disintegrate in the atmosphere and never make it to the ground. The Moon also encounters the same meteoroid flux, but has no atmosphere to stop them from striking the surface. At such speeds even a small meteoroid has incredible energy. A meteoroid with a mass of only 5 kg can excavate a crater over 9 m across, hurling 75 metric tons (165,000 lb) of lunar soil and rock on ballistic trajectories above the lunar surface. Meteoroids with particle sizes as small as 100 micrometer (1 Microgram) can do considerable damage to spacecraft in Earth's orbit and beyond. Impacts can damage thermal protection systems, radiators, windows, and pressurized containers. Secondary effects might include partial penetration or pitting, local deformation, and surface degradation that can cause a failure upon reentry. The speed, mass, density, and flux of meteoroids are important factors for design considerations and mitigation during operations. Lunar operations (unmanned and manned) are also adversely affected by the meteoroid flux. Ejecta from meteoroid impacts is also part of the lunar environment and must be characterized. Understanding meteoroid fluxes and the associated risk of meteoroids impacting spacecraft traveling in and beyond Earth's orbit is the objective of the Meteoroid Environment Office (MEO) located at Marshall Space Flight Center (MSFC). One of the MEO's programs is meteoroid impact monitoring of the Moon. The large collecting area of the night side of the lunar disk provides statistically significant counts of meteoroids that can provide useful information about the flux of meteoroids in the hundreds of grams to kilograms size range. This information is not only important for characterizing

  6. Venus - Impact Crater 'Jeanne

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This Magellan full-resolution image shows Jeanne crater, a 19.5 kilometer (12 mile) diameter impact crater. Jeanne crater is located at 40.0 degrees north latitude and 331.4 degrees longitude. The distinctive triangular shape of the ejecta indicates that the impacting body probably hit obliquely, traveling from southwest to northeast. The crater is surrounded by dark material of two types. The dark area on the southwest side of the crater is covered by smooth (radar-dark) lava flows which have a strongly digitate contact with surrounding brighter flows. The very dark area on the northeast side of the crater is probably covered by smooth material such as fine-grained sediment. This dark halo is asymmetric, mimicking the asymmetric shape of the ejecta blanket. The dark halo may have been caused by an atmospheric shock or pressure wave produced by the incoming body. Jeanne crater also displays several outflow lobes on the northwest side. These flow-like features may have formed by fine-grained ejecta transported by a hot, turbulent flow created by the arrival of the impacting object. Alternatively, they may have formed by flow of impact melt.

  7. Venus - Impact Crater Jeanne

    NASA Image and Video Library

    1996-11-20

    This full-resolution image from NASA Magellan spacecraft shows Jeanne crater, a 19.5 kilometer (12 mile) diameter impact crater. Jeanne crater is located at 40.0 degrees north latitude and 331.4 degrees longitude. The distinctive triangular shape of the ejecta indicates that the impacting body probably hit obliquely, traveling from southwest to northeast. The crater is surrounded by dark material of two types. The dark area on the southwest side of the crater is covered by smooth (radar-dark) lava flows which have a strongly digitate contact with surrounding brighter flows. The very dark area on the northeast side of the crater is probably covered by smooth material such as fine-grained sediment. This dark halo is asymmetric, mimicking the asymmetric shape of the ejecta blanket. The dark halo may have been caused by an atmospheric shock or pressure wave produced by the incoming body. Jeanne crater also displays several outflow lobes on the northwest side. These flow-like features may have formed by fine-grained ejecta transported by a hot, turbulent flow created by the arrival of the impacting object. Alternatively, they may have formed by flow of impact melt. http://photojournal.jpl.nasa.gov/catalog/PIA00472

  8. Crater with Exposed Layers

    NASA Image and Video Library

    2017-01-17

    On Earth, geologists can dig holes and pull up core samples to find out what lies beneath the surface. On Mars, geologists cannot dig holes very easily themselves, but a process has been occurring for billions of years that has been digging holes for them: impact cratering. Impact craters form when an asteroid, meteoroid, or comet crashes into a planet's surface, causing an explosion. The energy of the explosion, and the resulting size of the impact crater, depends on the size and density of the impactor, as well as the properties of the surface it hits. In general, the larger and denser the impactor, the larger the crater it will form. The impact crater in this image is a little less than 3 kilometers in diameter. The impact revealed layers when it excavated the Martian surface. Layers can form in a variety of different ways. Multiple lava flows in one area can form stacked sequences, as can deposits from rivers or lakes. Understanding the geology around impact craters and searching for mineralogical data within their layers can help scientists on Earth better understand what the walls of impact craters on Mars expose. http://photojournal.jpl.nasa.gov/catalog/PIA12328

  9. Mesospheric temperature estimation from meteor decay times during Geminids meteor shower

    NASA Astrophysics Data System (ADS)

    Kozlovsky, Alexander; Lukianova, Renata; Shalimov, Sergey; Lester, Mark

    2016-02-01

    Meteor radar observations at the Sodankylä Geophysical Observatory (67° 22'N, 26° 38'E, Finland) indicate that the mesospheric temperature derived from meteor decay times is systematically underestimated by 20-50 K during the Geminids meteor shower which has peak on 13 December. A very good coincidence of the minimum of routinely calculated temperature and maximum of meteor flux (the number of meteors detected per day) was observed regularly on that day in December 2008-2014. These observations are for a specific height-lifetime distribution of the Geminids meteor trails and indicate a larger percentage of overdense trails compared to that for sporadic meteors. A consequence of this is that the routine estimates of mesospheric temperature during the Geminids are in fact underestimates. The observations do, however, indicate unusual properties (e.g., mass, speed, or chemical composition) of the Geminids meteoroids. Similar properties were found also for Quadrantids in January 2009-2015, which like the Geminids has as a parent body an asteroid, but not for other meteor showers.

  10. Meteor beliefs project: Meteoric imagery in the works of William Blake

    NASA Astrophysics Data System (ADS)

    McBeath, A.

    2004-12-01

    Meteoric images, which are sometimes not clearly distinguishable from cometary ones, in the poems and artworks of Englishman William Blake (1757-1827) are presented and discussed. Attention is drawn too the turbulent events that occurred during Blake's lifetime, and which influenced his work. An annotated timeline, including major cometary, meteoric and meteoritic occurrences, covering 1757-1827, is also given.

  11. Venus - Mead Crater

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This Magellan image mosaic shows the largest (275 kilometers in diameter [170 miles]) impact crater known to exist on Venus at this point in the Magellan mission. The crater is located north of Aphrodite Terra and east of Eistla Regio at latitude 12.5 degrees north and longitude 57.4 degrees east, and was imaged during Magellan orbit 804 on November 12, 1990. The Magellan science team has proposed to name this crater Mead, after Margaret Mead, the American Anthropologist (1901- 1978). All Magellan-based names of features on Venus are, of course, only proposed until final approval is given by the International Astronomical Union-Commission on Planetary Nomenclature. Mead is classified as a multi-ring crater with its innermost, concentric scarp being interpreted as the rim of the original crater cavity. No inner peak-ring of mountain massifs is observed on Mead. The presence of hummocky, radar-bright crater ejecta crossing the radar-dark floor terrace and adjacent outer rim scarp suggests that the floor terrace is probably a giant rotated block that is concentric to, but lies outside of, the original crater cavity. The flat, somewhat brighter inner floor of Mead is interpreted to result from considerable infilling of the original crater cavity by impact melt and/or by volcanic lavas. To the southeast of the crater rim, emplacement of hummocky ejecta appears to have been impeded by the topography of preexisting ridges, thus suggesting a very low ground-hugging mode of deposition for this material. Radar illumination on this and all other Magellan image products is from the left to the right in the scene.

  12. Doublet craters on Venus

    NASA Astrophysics Data System (ADS)

    Cook, Cheryl M.; Melosh, H. Jay; Bottke, William F.

    2003-09-01

    Of the impact craters on Earth larger than 20 km in diameter, 10-15% (3 out of 28) are doublets, having been formed by the simultaneous impact of two well-separated projectiles. The most likely scenario for their formation is the impact of well-separated binary asteroids. If a population of binary asteroids is capable of striking the Earth, it should also be able to hit the other terrestrial planets as well. Venus is a promising planet to search for doublet craters because its surface is young, erosion is nearly nonexistent, and its crater population is significantly larger than the Earth's. After a detailed investigation of single craters separated by less than 150 km and "multiple" craters having diameters greater than 10 km, we found that the proportion of doublet craters on Venus is at most 2.2%, significantly smaller than Earth's, although several nearly incontrovertible doublets were recognized. We believe this apparent deficit relative to the Earth's doublet population is a consequence of atmospheric screening of small projectiles on Venus rather than a real difference in the population of impacting bodies. We also examined "splotches," circular radar reflectance features in the Magellan data. Projectiles that are too small to form craters probably formed these features. After a careful study of these patterns, we believe that the proportion of doublet splotches on Venus (14%) is comparable to the proportion of doublet craters found on Earth (10-15%). Thus, given the uncertainties of interpretation and the statistics of small numbers, it appears that the doublet crater population on Venus is consistent with that of the Earth.

  13. Cratering on Small Bodies: Lessons from Eros

    NASA Astrophysics Data System (ADS)

    Chapman, C. R.

    2003-01-01

    Cratering and regolith processes on small bodies happen continuously as interplanetary debris rains down on asteroids, comets, and planetary satellites. Butthey are very poorly observed and not well understood. On the one hand, we have laboratory experimentation at small scales and we have examination of large impact craters (e.g. Meteor Crater on Earth and imaging of abundant craters on terrestrial planets and outer planet moons). Understanding cratering on bodies of intermediate scales, tens of meters to hundreds of km in size, involves either extrapolation from our understanding of cratering phenomena at very different scales or reliance on very preliminary, incomplete examination of the observational data we now have for a few small bodies. I review the latter information here. It has been generally understood that the role of gravity is greatly diminished for smaller bodies, so a lot of cratering phenomena studied for larger bodies is less applicable. But it would be a mistake to imagine that laboratory experiments on gravitationless rocks (usually at 1 g) are directly applicable, except perhaps to those monolithic Near Earth Asteroids (NEAs) some tens of meters in size that spin very rapidly and can be assumed to be "large bare rocks" with "negative gravity". Whereas it had once been assumed that asteroids smaller than some tens of km diameter would retain little regolith, it is increasingly apparent that regolith and megoregolith processes extend down to bodies only hundreds of meters in size, perhaps smaller. Yet these processes are very different from those that pertain to the Moon, which is our chief prototype of regolith processes. The NEAR Shoemaker spacecraft's studies of Eros provide the best evidence to date about small-body cratering processes, as well as a warning that our theoretical understanding requires anchoring by direct observations. Eros: "Ponds", Paucity of Small Craters, and Other Mysteries. Although Eros is currently largely detached

  14. Lunar secondary craters, part K

    NASA Technical Reports Server (NTRS)

    Overbeck, V. R.; Morrison, R. H.; Wedekind, J.

    1972-01-01

    Formation of V-shaped structures surrounding the fresh Copernicus Crater and its secondary craters are reviewed, and preliminary observations of the more extensively eroded secondary crater field of Theophilus are presented. Results of laboratory simulation of secondary lunar craters to examine their effects on V-shaped ridges are also described.

  15. An Inverted Crater

    NASA Image and Video Library

    2016-06-01

    There is a circular feature in this observation from NASA Mars Reconnaissance Orbiter spacecraft that appears to stand above the surrounding terrain. This feature is probably an inverted crater that was filled in with sediment. The fill became indurated, or hardened, until it was more resistant to subsequent erosion than the surrounding material. Other craters in this image are not inverted or substantially infilled. This suggests that they were formed after the events that filled in and later exposed the inverted crater. http://photojournal.jpl.nasa.gov/catalog/PIA20729

  16. Central Pit Crater

    NASA Image and Video Library

    2015-11-13

    Crater floors can have a range of features, from flat to a central peak or a central pit. This image from NASA 2001 Mars Odyssey spacecraft shows an unnamed crater in Terra Sabaea has a central pit. This unnamed crater in Terra Sabaea has a central pit. The different floor features develop do due several factors, including the size of the impactor, the geology of the surface material and the geology of the materials at depth. Orbit Number: 60737 Latitude: 22.3358 Longitude: 61.2019 Instrument: VIS Captured: 2015-08-23 20:13 http://photojournal.jpl.nasa.gov/catalog/PIA20092

  17. Crater in Utopia

    NASA Technical Reports Server (NTRS)

    2004-01-01

    23 March 2004 Craters of the martian northern plains tend to be somewhat shallow because material has filled them in. Their ejecta blankets, too, are often covered by younger materials. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example--a crater in Utopia Planitia near 43.7oN, 227.3oW. Erosion has roughened some of the surfaces of the material that filled the crater and covered its ejecta deposit. The picture covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the lower left.

  18. Venus - Crater Aurelia

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This Magellan image shows a complex crater, 31.9 kilometers (20 miles) in diameter with a circular rim, terraced walls, and central peaks, located at 20.3 degrees north latitude and 331.8 degrees east longitude. Several unusual features are evidenced in this image: large dark surface up range from the crater; lobate flows emanating from crater ejecta, and very radar-bright ejecta and floor. Aurelia has been proposed to the International Astronomical Union, Subcommittee of Planetary Nomenclature as a candidate name. Aurelia is the mother of Julius Caesar.

  19. The Southern Argentine Agile Meteor Radar (SAAMER)

    NASA Astrophysics Data System (ADS)

    Janches, Diego

    2014-11-01

    The Southern Argentina Agile Meteor Radar (SAAMER) is a new generation system deployed in Rio Grande, Tierra del Fuego, Argentina (53 S) in May 2008. SAAMER transmits 10 times more power than regular meteor radars, and uses a newly developed transmitting array, which focuses power upward instead of the traditional single-antenna-all-sky configuration. The system is configured such that the transmitter array can also be utilized as a receiver. The new design greatly increases the sensitivity of the radar enabling the detection of large number of particles at low zenith angles. The more concentrated transmitted power enables additional meteor studies besides those typical of these systems based on the detection of specular reflections, such as routine detections of head echoes and non-specular trails, previously only possible with High Power and Large Aperture radars. In August 2010, SAAMER was upgraded to a system capable to determine meteoroid orbital parameters. This was achieved by adding two remote receiving stations approximately 10 km away from the main site in near perpendicular directions. The upgrade significantly expands the science that is achieved with this new radar enabling us to study the orbital properties of the interplanetary dust environment. Because of the unique geographical location, SAAMER allows for additional inter-hemispheric comparison with measurements from Canadian Meteor Orbit Radar, which is geographically conjugate. Initial surveys show, for example, that SAAMER observes a very strong contribution of the South Toroidal Sporadic meteor source, of which limited observational data is available. In addition, SAAMER offers similar unique capabilities for meteor showers and streams studies given the range of ecliptic latitudes that the system enables detailed study of showers at high southern latitudes (e.g July Phoenicids or Puppids complex). Finally, SAAMER is ideal for the deployment of complementary instrumentation in both, permanent

  20. State-of-the-art meteor observing

    NASA Astrophysics Data System (ADS)

    Campbell-Brown, M.

    2014-07-01

    Meteors are an excellent way to sample the local population of small asteroidal and cometary material. Various methods are used to calculate the trajectory, energy, mass and orbit of meteoroids which collide with the atmosphere. Optical methods, including photographic and video observations, can provide information on how meteoroids ablate in the atmosphere, and from this their chemical and physical properties can be inferred. New observing systems have higher resolution than ever before, allowing details as small as a few meters to be distinguished in some cases (e.g. Weryk et al. 2013), and some optical systems are equipped with spectral detectors which allow the atomic composition of the meteoroids to be obtained. Computer automation of both the observing and data reduction process has become much more practical recently. Meteor patrol radars are capable of observing thousands of meteor orbits every day, allowing the details of the distribution of meteoroids at 1 au to be found (e.g. Brown et al. 2010). Radars can operate in daylight and through clouds, providing observations when optical methods fail. High power, large aperture radars allow the ionization curves of very small meteors to be used in the same way as optical light curves, and can also produce precise orbits for meteoroids (Kero et al. 2012). Other methods used to observe meteors, including infrasound, can estimate their position in the atmosphere and their energy, and are particularly useful for very bright fireballs (Ens et al., 2012). Recent advances in meteor observing techniques will be reviewed, including the systematic tracking of meteors with computer guided mirrors and a telescope, and multistation patrol radar observations.

  1. Tritium concentrations in the active Pu'u O'o crater, Kilauea volcano, Hawaii: implications for cold fusion in the Earth's interior

    USGS Publications Warehouse

    Quick, J.E.; Hinkley, T.K.; Reimer, G.M.; Hedge, C.E.

    1991-01-01

    The assertion that deuterium-deuterium fusion may occur at low temperature suggests a potential new source of geothermal heat. If a cold-fusion-like process occurs within the Earth, then a test for its existence would be a search for anomalous tritium in volcanic emissions. The Pu'u O'o crater is the first point at which large amounts of water are degassed from the magma that feeds the Kilauea system. The magma is probably not contaminated by meteoric-source ground water prior to degassing at Pu'u O'o, although mixing of meteoric and magmatic H2O occurs within the crater. Tritium contents of samples from within the crater are lower than in samples taken simultaneously from the nearby upwind crater rim. These results provide no evidence in support of a cold-fusion-like process in the Earth's interior. ?? 1991.

  2. Meteoroids and impact craters

    USGS Publications Warehouse

    Spall, H.

    1986-01-01

    Many meteoroids are associted with comets; as a comet travels around the sun it leaves a trail of debris behind it and it is this debris which produces meteor showers. Other meteoroids come from the asteroid belt, a zone between Mars and Jupiter filled with thousands of dwarf worlds that failed to coalesce into planets. 

  3. Arizona Telemedicine Program

    PubMed Central

    McNeill, Kevin M.; Weinstein, Ronald S.; Holcomb, Michael J.

    1998-01-01

    The Arizona Telemedicine Program was established in July 1996 by the Arizona state legislature. The organizational center for the program is the Arizona Health Sciences Center in Tucson. Key goals for the program include increased access to specialty services for rural, underserved populations; development of cost-effective telemedicine services; and expansion of opportunities for education of health professionals in rural areas. The program provides several levels of services based on both store-and-forward and real-time interactive applications. The telecommunication infrastructure is provided by two methods: The first is a private asynchronous transfer mode network established and operated by program personnel. The second is dial-up access via the public switched telephone network. After an extensive period of organization and vendor evaluations, most of the private network was implemented between June and December 1997. This paper describes experiences establishing the asynchronous transfer mode network. PMID:9760392

  4. Geologic evolution of Arizona

    SciTech Connect

    Penny, J.P.; Reynolds, S.J.

    1989-01-01

    Seven years in the making, the 35 papers in this volume summarize the stratigraphic, structural, and tectonic evolution of Arizona from Precambrian through Quaternary time. Intended as a compendium of current knowledge of Arizona geology, the papers synthesize previous work with new data, ideas, and concepts as well as identifying unresolved problems for future research. Emphasis is placed on the geologic evolution of the state as a whole rather than specific local areas. The papers are organized in terms of geologic eras: Proterozoic, Paleozoic, Mesozoic, and Cenozoic. The concluding section offers topical studies in the areas of geophysics, industrial minerals, uranium, oil and gas, geothermal resources, hydrogeology, and environmental geology. California readers will find much of interest in this research volume because many of the tectonic processes that formed Arizona also affected the development of this state.

  5. Secondary crater fields from 24 large primary craters on Mars: Insights into nearby secondary crater production

    NASA Astrophysics Data System (ADS)

    Robbins, Stuart J.; Hynek, Brian M.

    2011-10-01

    Crater statistics are used across a wide variety of applications on planetary surfaces, one of the most notable being estimating relative and absolute ages of those surfaces. This requires an assumed cratering rate over time and that craters be randomly distributed. Secondary craters - craters that form from the ejecta of an impact event - belie this assumption by creating greater crater density in a local area at a single time, significantly affecting crater statistics. There has been substantial debate over the relative importance of secondary craters, and our findings in this Mars study indicate that these events can be very significant and cannot be ignored when age-dating surfaces. We have analyzed secondary crater fields found close to 24 primary craters on Mars. Among other findings such as terrain control over secondary crater field characteristics, we conclude that a single large impact event (>100 km) can significantly affect crater statistics at the ˜1-5-km-diameter level over a non-trivial fraction of a planetary surface (minimum secondary crater diameters examined were ˜0.9 km; the minimum primary crater diameter was ˜20 km). We also suggest a potential way to avoid significant contamination by the majority of secondary craters that occur close to the primary impact event without the need to manually classify every crater as primary or secondary. Our findings are specific to Mars, but further work may show the patterns are applicable to other solid bodies.

  6. Clouds Near Mie Crater

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-572, 12 December 2003

    Mie Crater, a large basin formed by asteroid or comet impact in Utopia Planitia, lies at the center of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle image. The crater is approximately 104 km (65 mi) across. To the east and southeast (toward the lower right) of Mie, in this 5 December 2003 view, are clouds of dust and water ice kicked up by local dust storm activity. It is mid-winter in the northern hemisphere of Mars, a time when passing storms are common on the northern plains of the red planet. Sunlight illuminates this image from the lower left; Mie Crater is located at 48.5oN, 220.3oW. Viking 2 landed west/southwest of Mie Crater, off the left edge of this image, in September 1976.

  7. Ravi Vallis Crater

    NASA Image and Video Library

    2013-10-28

    This image shows another portion of Ravi Vallis. In this image taken by NASA 2001 Mars Odyssey spacecraft, a small crater and the resistant material formed during the impact form a donut on the floor of the valley.

  8. Craters in the Classroom.

    ERIC Educational Resources Information Center

    McArdle, Heather K.

    1997-01-01

    Details an activity in which students create and study miniature impact craters in the classroom. Engages students in making detailed, meaningful observations, drawing inferences, reaching conclusions based on scientific evidence, and designing experiments to test selected variables. (DDR)

  9. Shackleton Crater Illumination

    NASA Image and Video Library

    Simulated illumination conditions near the lunar South Pole. The 30km x 30km region highlights the Shackleton crater. The movie runs for 28 days, centered on the LCROSS impact date on October 9th, ...

  10. Hazardous crater lakes studied

    NASA Astrophysics Data System (ADS)

    Kusakabe, Minoru

    Crater lakes usually sit on top of volcanic conduits and act as condensers of magmatic vapor. Studies of crater lakes can therefore provide information on both deep magmatic activity and variations in the degassing state of a shallow magmatic body. The Lake Nyos gas disaster of August 1986 and a similar event in August 1984 at Lake Monoun, both in Cameroon, resulted from the accumulation of magmatic CO2 in the bottom layers of the lakes. Geochemical monitoring of crater lakes is a promising tool for forecasting not only limnic but also volcanic eruptions. Acid-mineralized waters formed by condensation of hot magmatic volatiles in crater lakes are thought to bear some resemblance to hydrothermal fluids acting in the genesis of acid-sulfate alteration and Au-Cu-Ag mineralization of volcanic-hosted precious metal deposits.

  11. Trouvelot Crater Deposit

    NASA Image and Video Library

    2002-12-04

    Like many of the craters in the Oxia Palus region of Mars, Trouvelot Crater, shown in this NASA Mars Odyssey image, hosts an eroded, light-toned, sedimentary deposit on its floor. Compared with the much larger example in Becquerel Crater to the NE, the Trouvelot deposit has been so eroded by the scouring action of dark, wind-blown sand that very little of it remains. Tiny outliers of bright material separated from the main mass attest to the once, more really extensive coverage by the deposit. A similar observation can be made for White Rock, the best known example of a bright, crater interior deposit. The origin of the sediments in these deposits remains enigmatic but they are likely the result of fallout from ash or dust carried by the thin martian atmosphere. http://photojournal.jpl.nasa.gov/catalog/PIA04017

  12. Exhumed Crater with Slope

    NASA Technical Reports Server (NTRS)

    2004-01-01

    MGS MOC Release No. MOC2-575, 15 December 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a crater in Arabia Terra that has been exhumed. The picture was acquired less than 1 week ago, on 9 December 2003. The crater was buried beneath layered material, but erosion later brought it back to the surface. A thick blanket of dust mantles the scene; dark streaks have formed as some of this dust slid down the crater walls. Old, dust-covered ripples of windblown sediment occur on the floor of the exhumed crater. The image is located near 20.9oN, 320.7oW, and covers an area 3 km (1.9 mi) wide; sunlight illuminates the scene from the lower left.

  13. Craters in the Classroom.

    ERIC Educational Resources Information Center

    McArdle, Heather K.

    1997-01-01

    Details an activity in which students create and study miniature impact craters in the classroom. Engages students in making detailed, meaningful observations, drawing inferences, reaching conclusions based on scientific evidence, and designing experiments to test selected variables. (DDR)

  14. Rubria and Occia Craters

    NASA Image and Video Library

    2012-05-09

    This image from NASA Dawn spacecraft of asteroid Vesta shows Rubria and Occia craters. Both Rubria and Occia contain dark and bright material and both have reasonably sharp, well-defined and regularly shaped rims.

  15. Poynting Crater Ejecta

    NASA Image and Video Library

    2002-08-05

    Located roughly equidistant between two massive volcanoes, the approximately 60 km Poynting Crater and its ejecta, shown in this image from NASA Mars Odyssey spacecraft, have experienced an onslaught of volcanic activity.

  16. Chipped Paint Crater

    NASA Image and Video Library

    2003-04-09

    In the high northern latitudes northwest of Alba Patera, a smooth mantle of material that covers the landscape appears chipped away from the rim of a large crater, as observed in this image from NASA Mars Odyssey spacecraft.

  17. Stop Sign Crater

    NASA Image and Video Library

    2003-03-06

    With its rim eroded off by catastrophic floods in Tiu Vallis and its strangely angular shape, this 12 km about 7.5 mile diameter crater imaged by NASA Mars Odyssey spacecraft looks vaguely like a stop sign.

  18. Exhumed Craters near Kaiser

    NASA Technical Reports Server (NTRS)

    2004-01-01

    24 August 2004 The upper left (northwest) corner of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a crater within which are several layers of eroded material. This crater, and probably all of its degraded neighbors, was once filled and buried, and was later exhumed. The burial and exhumation theme is one that repeats all over the surface of Mars, as ancient rocks are eroded to expose previously filled and buried craters, valleys, and landscapes. This particular image is located near the northwest rim of Kaiser Crater, in Noachis Terra, near 45.2oS, 342.7oW. The image covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the upper left.

  19. CAMS confirmation of previously reported meteor showers

    NASA Astrophysics Data System (ADS)

    Jenniskens, P.; Nénon, Q.; Gural, P. S.; Albers, J.; Haberman, B.; Johnson, B.; Holman, D.; Morales, R.; Grigsby, B. J.; Samuels, D.; Johannink, C.

    2016-03-01

    Leading up to the 2015 IAU General Assembly, the International Astronomical Union's Working List of Meteor Showers included 486 unconfirmed showers, showers that are not certain to exist. If confirmed, each shower would provide a record of past comet or asteroid activity. Now, we report that 41 of these are detected in the Cameras for Allsky Meteor Surveillance (CAMS) video-based meteor shower survey. They manifest as meteoroids arriving at Earth from a similar direction and orbit, after removing the daily radiant drift due to Earth's motion around the Sun. These showers do exist and, therefore, can be moved to the IAU List of Established Meteor Showers. This adds to 31 previously confirmed showers from CAMS data. For each shower, finding charts are presented based on 230,000 meteors observed up to March of 2015, calculated by re-projecting the drift-corrected Sun-centered ecliptic coordinates into more familiar equatorial coordinates. Showers that are not detected, but should have, and duplicate showers that project to the same Sun-centered ecliptic coordinates, are recommended for removal from the Working List.

  20. BRAMS: The Belgian RAdio Meteor Stations

    NASA Technical Reports Server (NTRS)

    Lamy, H.; Ranvier, S.; De Keyser, J.; Calders, S.; Gamby, E.; Verbeeck, C.

    2011-01-01

    In the last months, the Belgian Institute for Space Aeronomy has been developing a Belgian network for observing radio meteors using forward scattering technique. This network is called BRAMS for Belgian RAdio Meteor Stations. Two beacons emitting a circularly polarized pure sine wave toward the zenith act as the transmitters at frequencies of 49.97 and 49.99 MHz. The first one located in Dourbes (Southern Belgium) emits a constant power of 150 Watts while the one located in Ieper (Western Belgium) emits a constant power of 50 Watts. The receiving network consists of about 20 stations hosted mainly by radio amateurs. Two stations have crossed-Yagi antennas measuring horizontal and vertical polarizations of the waves reflected off meteor trails. This will enable a detailed analysis of the meteor power profiles from which physical parameters of the meteoroids can be obtained. An interferometer consisting of 5 Yagi-antennas will be installed at the site of Humain in order to determine the angular detection of one reflection point, allowing us to determine meteoroid trajectories. We describe this new meteor observing facility and present the goals we expect to achieve with the network.

  1. A spectral analysis of ablating meteors

    NASA Astrophysics Data System (ADS)

    Bloxam, K.; Campbell-Brown, M.

    2017-09-01

    Meteor ablation features in the spectral lines occurring at 394, 436, 520, and 589 nm were observed using a four-camera spectral system between September and December 2015. In conjunction with this multi-camera system the Canadian Automated Meteor Observatory was used to observe the orbital parameters and fragmentation of these meteors. In total, 95 light curves with complete data in the 520 and 589 nm filters were analyzed; some also had partial or complete data in the 394 nm filter, but no usable data was collected with the 436 nm filter. Of the 95 events, 70 exhibited some degree of differential ablation, and in all except 3 of these 70 events the 589 nm filter started or ended sooner compared with the 520 nm filter, indicating early ablation at the 589 nm wavelength. In the majority of cases the meteor showed evidence of fragmentation regardless of the type of ablation (differential or uniform). A surprising result was the lack of correlation found concerning the KB parameter, linked to meteoroid strength, and differential ablation. In addition, 22 shower-associated meteors were observed; Geminids showed mainly slight differential ablation, while Taurids were more likely to ablate uniformly.

  2. Asteroid 1620 Geographos: II. Associated Meteor Streams

    NASA Astrophysics Data System (ADS)

    Ryabova, G. O.

    2002-05-01

    This study attempts to answer the following questions. Are there meteor streams genetically related to asteroid 1620 Geographos? When and how were they generated? Can we find any of them in the catalogs of orbits of meteors that have been observed? Numerous model streams, varying in particle-ejection scheme and in the moment of generation, have been considered. It has been found that the meteor streams observed from the Earth were most likely produced as a result of a collision with a small body. However, the generation of the meteor stream under the combined effect of rotation and tidal forces during the asteroid's close approach to the Earth cannot also be ruled out. Meteoroid streams formed at high ejection velocities (up to 1 km/s) can approach the Earth's orbit twice per orbital period: once before perihelion (in February-March) and once after perihelion (in August). The 44 orbits close to the model ones were found in the catalogs of meteoroid orbits. A taxonomic structure has been built for them. The distribution of ejection velocities for the models of Earth-approaching meteoroids points to the impact of an overtaking body, but the moment of collision remains unknown. Thus, it is quite possible that asteroid Geographos is the parent body for twin meteor showers observed at the Earth: Spring and Autumn Geographids.

  3. Multivariate analyses of crater parameters and the classification of craters

    NASA Technical Reports Server (NTRS)

    Siegal, B. S.; Griffiths, J. C.

    1974-01-01

    Multivariate analyses were performed on certain linear dimensions of six genetic types of craters. A total of 320 craters, consisting of laboratory fluidization craters, craters formed by chemical and nuclear explosives, terrestrial maars and other volcanic craters, and terrestrial meteorite impact craters, authenticated and probable, were analyzed in the first data set in terms of their mean rim crest diameter, mean interior relief, rim height, and mean exterior rim width. The second data set contained an additional 91 terrestrial craters of which 19 were of experimental percussive impact and 28 of volcanic collapse origin, and which was analyzed in terms of mean rim crest diameter, mean interior relief, and rim height. Principal component analyses were performed on the six genetic types of craters. Ninety per cent of the variation in the variables can be accounted for by two components. Ninety-nine per cent of the variation in the craters formed by chemical and nuclear explosives is explained by the first component alone.

  4. Juling and Kupalo Craters

    NASA Image and Video Library

    2017-08-17

    This region on Ceres, located in the vicinity of Toharu Crater, presents two small craters: Juling at top (12 miles, 20 kilometers in diameter) and Kupalo at bottom (16 miles, 26 kilometers in diameter). Both craters are relatively young, as indicated by their sharp rims. These features are located at about the same latitude (about 38 degrees south) as Tawals Crater and show similar crater shapes and rugged terrain. These features may reflect the presence of ice below the surface. Subtle bright features can be distinguished in places. These likely were excavated by small impacts and landslides along the slopes of the crater rims. This suggests that a different type of material, likely rich in salts, is present in the shallow subsurface. Juling is named after the Sakai/Orang Asli spirit of the crops from Malaysia, and Kupalo gets its name from the Russian god of vegetation and of the harvest. NASA's Dawn spacecraft acquired this picture on August 24, 2016. The image was taken during Dawn's extended mission, from its low altitude mapping orbit at about 240 miles (385 kilometers) above the surface. The center coordinates of this image are 38 degrees south latitude, 165 degrees east longitude. https://photojournal.jpl.nasa.gov/catalog/PIA21753

  5. Mercury's Densely Cratered Surface

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Mariner 10 took this picture (FDS 27465) of the densely cratered surface of Mercury when the spacecraft was 18,200 kilometers (8085 miles) from the planet on March 29. The dark line across top of picture is a 'dropout' of a few TV lines of data. At lower left, a portion of a 61 kilometer (38 mile) crater shows a flow front extending across the crater floor and filling more than half of the crater. The smaller, fresh crater at center is about 25 kilometers (15 miles) in diameter. Craters as small as one kilometer (about one-half mile) across are visible in the picture.

    The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

    Image Credit: NASA/JPL/Northwestern University

  6. Granular Crater Formation

    NASA Astrophysics Data System (ADS)

    Clark, Abe; Behringer, Robert; Brandenburg, John

    2009-11-01

    This project characterizes crater formation in a granular material by a jet of gas impinging on a granular material, such as a retro-rocket landing on the moon. We have constructed a 2D model of a planetary surface, which consists of a thin, clear box partially filled with granular materials (sand, lunar and Mars simulants...). A metal pipe connected to a tank of nitrogen gas via a solenoid valve is inserted into the top of the box to model the rocket. The results are recorded using high-speed video. We process these images and videos in order to test existing models and develop new ones for describing crater formation. A similar set-up has been used by Metzger et al.footnotetextP. T. Metzger et al. Journal of Aerospace Engineering (2009) We find that the long-time shape of the crater is consistent with a predicted catenary shape (Brandenburg). The depth and width of the crater both evolve logarithmically in time, suggesting an analogy to a description in terms of an activated process: dD/dt = A (-aD) (D is the crater depth, a and A constants). This model provides a useful context to understand the role of the jet speed, as characterized by the pressure used to drive the flow. The box width also plays an important role in setting the width of the crater.

  7. Pandora Fretum Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site] (Released 26 July 2002) Another in a series of craters with unusual interior deposits, this THEMIS image shows an unnamed crater in the southern hemisphere Pandora Fretum region near the Hellas Basin. Craters with eroded layered deposits are quite common on Mars but the crusty textured domes in the center of the image make this crater more unusual. Looking vaguely like granitic intrusions, there erosional style is distinct from the rest of the interior deposit which shows a very obvious layered morphology. While it is unlikely that the domes are granite plutons, it is possible that they do represent some other shallowly emplaced magmatic intrusion. More likely still is that variations in induration of the layered deposit allow for variations in the erosional morphology. Note how the surface of the crater floor in the northernmost portion of the image has a texture similar to that of the domes. This may represent an incipient form of the erosion that has produced the domes but has not progressed as far. An analysis of other craters in the area may shed light on the origin of the domes.

  8. Named Venusian craters

    NASA Astrophysics Data System (ADS)

    Russell, Joel F.; Schaber, Gerald G.

    1993-03-01

    Schaber et al. compiled a database of 841 craters on Venus, based on Magellan coverage of 89 percent of the planet's surface. That database, derived from coverage of approximately 98 percent of Venus' surface, has been expanded to 912 craters, ranging in diameter from 1.5 to 280 km. About 150 of the larger craters were previously identified by Pioneer Venus and Soviet Venera projects and subsequently formally named by the International Astronomical Union (IAU). Altogether, the crater names submitted to the IAU for approval to date number about 550, a little more than half of the number of craters identified on Magellan images. The IAU will consider more names as they are submitted for approval. Anyone--planetary scientist or layman--may submit names; however, candidate names must conform to IAU rules. The person to be honored must be deceased for at least three years, must not be a religious figure or a military or political figure of the 19th or 20th century, and, for Venus, must be a woman. All formally and provisionally approved names for Venusian impact craters, along with their latitude, longitude, size, and origin of their name, will be presented at LPSC and will be available as handouts.

  9. Optical Meteor Systems Used by the NASA Meteoroid Environment Office

    NASA Technical Reports Server (NTRS)

    Kingery, A. M.; Blaauw, R. C.; Cooke, W. J.; Moser, D. E.

    2015-01-01

    The NASA Meteoroid Environment Office (MEO) uses two main meteor camera networks to characterize the meteoroid environment: an all sky system and a wide field system to study cm and mm size meteors respectively. The NASA All Sky Fireball Network consists of fifteen meteor video cameras in the United States, with plans to expand to eighteen cameras by the end of 2015. The camera design and All-Sky Guided and Real-time Detection (ASGARD) meteor detection software [1, 2] were adopted from the University of Western Ontario's Southern Ontario Meteor Network (SOMN). After seven years of operation, the network has detected over 12,000 multi-station meteors, including meteors from at least 53 different meteor showers. The network is used for speed distribution determination, characterization of meteor showers and sporadic sources, and for informing the public on bright meteor events. The NASA Wide Field Meteor Network was established in December of 2012 with two cameras and expanded to eight cameras in December of 2014. The two camera configuration saw 5470 meteors over two years of operation with two cameras, and has detected 3423 meteors in the first five months of operation (Dec 12, 2014 - May 12, 2015) with eight cameras. We expect to see over 10,000 meteors per year with the expanded system. The cameras have a 20 degree field of view and an approximate limiting meteor magnitude of +5. The network's primary goal is determining the nightly shower and sporadic meteor fluxes. Both camera networks function almost fully autonomously with little human interaction required for upkeep and analysis. The cameras send their data to a central server for storage and automatic analysis. Every morning the servers automatically generates an e-mail and web page containing an analysis of the previous night's events. The current status of the networks will be described, alongside with preliminary results. In addition, future projects, CCD photometry and broadband meteor color camera

  10. All-sky Meteor Orbit System AMOS and preliminary analysis of three unusual meteor showers

    NASA Astrophysics Data System (ADS)

    Tóth, Juraj; Kornoš, Leonard; Zigo, Pavol; Gajdoš, Štefan; Kalmančok, Dušan; Világi, Jozef; Šimon, Jaroslav; Vereš, Peter; Šilha, Jiří; Buček, Marek; Galád, Adrián; Rusňák, Patrik; Hrábek, Peter; Ďuriš, František; Rudawska, Regina

    2015-12-01

    All-sky Meteor Orbit System (AMOS) is a semi-autonomous video observatory for detection of transient events on the sky, mostly the meteors. Its hardware and software development and permanent placement on several locations in Slovakia allowed the establishment of Slovak Video Meteor Network (SVMN) monitoring meteor activity above the Central Europe. The data reduction, orbital determination and additional results from AMOS cameras - the SVMN database - as well as from observational expeditions on Canary Islands and in Canada provided dynamical and physical data for better understanding of mutual connections between parent bodies of asteroids and comets and their meteoroid streams. We present preliminary results on exceptional and rare meteor streams such as September ɛ Perseids (SPE) originated from unknown long periodic comet on a retrograde orbit, suspected asteroidal meteor stream of April α Comae Berenicids (ACO) in the orbit of meteorites Příbram and Neuschwanstein and newly observed meteor stream Camelopardalids (CAM) originated from Jupiter family comet 209P/Linear.

  11. Analysis of historical meteor and meteor shower records: Korea, China, and Japan

    NASA Astrophysics Data System (ADS)

    Yang, Hong-Jin; Park, Changbom; Park, Myeong-Gu

    2005-05-01

    We have compiled and analyzed historical Korean meteor and meteor shower records in three Korean official history books, Samguksagi which covers the three Kingdoms period (57 B.C.-A.D. 935), Goryeosa of Goryeo dynasty (A.D. 918-1392), and Joseonwangjosillok of Joseon dynasty (A.D. 1392-1910). We have found 3861 meteor and 31 meteor shower records. We have confirmed the peaks of Perseids and an excess due to the mixture of Orionids, north-Taurids, or Leonids through the Monte Carlo test. The peaks persist from the period of Goryeo dynasty to that of Joseon dynasty, for almost one thousand years. Korean records show a decrease of Perseids activity and an increase of Orionids/north-Taurids/Leonids activity. We have also analyzed seasonal variation of sporadic meteors from Korean records. We confirm the seasonal variation of sporadic meteors from the records of Joseon dynasty with the maximum number of events being roughly 1.7 times the minimum. The Korean records are compared with Chinese and Japanese records for the same periods. Major features in Chinese meteor shower records are quite consistent with those of Korean records, particularly for the last millennium. Japanese records also show Perseids feature and Orionids/north-Taurids/Leonids feature, although they are less prominent compared to those of Korean or Chinese records.

  12. ROAN Remote radio meteor detection sensor

    NASA Astrophysics Data System (ADS)

    Lesanu, C. E.

    2016-01-01

    Only few meteor enthusiasts across the world today, approaches systematically the radio meteor detection technique, one of the reasons being the difficulty to build and install proper permanent antennas, especially when low-VHF frequency opportunity transmitters are used as illuminators. Other reasons were in the past the relatively high cost of the entire system, receivers and computers, and not ultimately the high power consumption of the system in a 24/7 operation, when using regular personal computers. The situation changed in the recent years with the advent of the low cost software defined radio SDR receivers and low consumption/cost single board computers SBC. A commercial off-the-shelf hardware based remote radio meteor detection sensor is presented.

  13. Protecting Venus from Asteroids, Comets, and Meteors

    NASA Technical Reports Server (NTRS)

    McKinnon, William B.; Zahnle, K. J.; Cuzzi, Jeffrey (Technical Monitor)

    1996-01-01

    It is well accepted that the dense, thick atmosphere of Venus prevents most small cosmic bodies from reaching the surface and forming craters. We have examined this atmospheric intervention in detail, incorporating the lessons learned from the extensive modeling of impactor deceleration and flattening motivated by the SL-9 impacts with Jupiter. We employ a "pancake" model, which best matches detailed code simulations of atmospheric energy deposition, and Schmidt-Holsapple crater scaling modified for complex (flattened) craters. We adopt the distributions of Venus-crossing asteroids and comets determined by E.M. Shoemaker and co-workers, as well as generalizations of these distributions. Our nominal simulation of the venusian crater record is shown below, calibrated to the total number of venusian craters (940). As nearly all craters on Venus are well-preserved and relatively uniformly distributed, such simulations constrain the age of the surface. The fit is reasonable, with a nominal crater retention age of approx. 700 Ma. The fit at the large-crater end is improved if the number of large asteroids is increased, which Shoemaker argues is in fact more representative of the long-term (over several 100 Ma) average, and if Halley-family comets are included. The ages we obtain under a variety of modeling choices that produce good fits (including using Shoemaker's preferred crater scaling) are approx. 700-900 Ma, substantially greater than the most widely cited age estimate in the literature (-300 Ma). The key difference is that we find very large depletions in the production of 20-30-km craters (see figure) compared with previous estimates, the size range at which atmospheric effects are often calibrated or assumed nearly negligible. As venusian global resurfacing recedes deeper into history, the likelihood that Venus is resting between bouts of activity diminishes. Venus, like Mars, may instead be dying or dead.

  14. Protecting Venus from Asteroids, Comets, and Meteors

    NASA Technical Reports Server (NTRS)

    McKinnon, William B.; Zahnle, K. J.; Cuzzi, Jeffrey (Technical Monitor)

    1996-01-01

    It is well accepted that the dense, thick atmosphere of Venus prevents most small cosmic bodies from reaching the surface and forming craters. We have examined this atmospheric intervention in detail, incorporating the lessons learned from the extensive modeling of impactor deceleration and flattening motivated by the SL-9 impacts with Jupiter. We employ a "pancake" model, which best matches detailed code simulations of atmospheric energy deposition, and Schmidt-Holsapple crater scaling modified for complex (flattened) craters. We adopt the distributions of Venus-crossing asteroids and comets determined by E.M. Shoemaker and co-workers, as well as generalizations of these distributions. Our nominal simulation of the venusian crater record is shown below, calibrated to the total number of venusian craters (940). As nearly all craters on Venus are well-preserved and relatively uniformly distributed, such simulations constrain the age of the surface. The fit is reasonable, with a nominal crater retention age of approx. 700 Ma. The fit at the large-crater end is improved if the number of large asteroids is increased, which Shoemaker argues is in fact more representative of the long-term (over several 100 Ma) average, and if Halley-family comets are included. The ages we obtain under a variety of modeling choices that produce good fits (including using Shoemaker's preferred crater scaling) are approx. 700-900 Ma, substantially greater than the most widely cited age estimate in the literature (-300 Ma). The key difference is that we find very large depletions in the production of 20-30-km craters (see figure) compared with previous estimates, the size range at which atmospheric effects are often calibrated or assumed nearly negligible. As venusian global resurfacing recedes deeper into history, the likelihood that Venus is resting between bouts of activity diminishes. Venus, like Mars, may instead be dying or dead.

  15. Arizona Academic Standards, Kindergarten

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2007

    2007-01-01

    This publication contains Arizona public schools' academic standards for kindergarten. The contents of this document include the following: (1) The Arts Standard 2006--Kindergarten; (2) Comprehensive Health Education/Physical Activity Standards 1997--Readiness (Kindergarten); (3) Foreign and Native Language Standards 1997--Essentials (Grades 4-8);…

  16. Arizona's Application Service Provider.

    ERIC Educational Resources Information Center

    Jordan, Darla

    2002-01-01

    Describes the U.S.'s first statewide K-12 application service provider (ASP). The ASP, implemented by the Arizona School Facilities Board, provides access to productivity, communications, and education software programs from any Internet-enabled device, whether in the classroom or home. (EV)

  17. Workforce Brief: Arizona

    ERIC Educational Resources Information Center

    Western Interstate Commission for Higher Education, 2006

    2006-01-01

    In Arizona, one of the country's fastest growing states, the demand for well-educated employees will only increase over the next several years. In the decade leading up to 2013, healthcare occupations will see growth of 50 percent. Almost 1,800 dentists will need to be hired to fill new posts and to cover retirement, for example. Teachers will be…

  18. Indians of Arizona.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    Brief descriptions of the historical and cultural background of the Navajo, Apache, Hopi, Pima, Papago, Yuma, Maricopa, Mohave, Cocopah, Havasupai, Hualapai, Yavapai, and Paiute Indian tribes of Arizona are presented. Further information is given concerning the educational, housing, employment, and economic development taking place on the…

  19. Indians of Arizona.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    Briefly describing each tribe within Arizona's four major American Indian groups, this handbook presents information relative to the cultural background and socioeconomic development of the following tribes: (1) Athapascan Tribes (Navajos and Apaches); (2) Pueblo Indians (Hopis); (3) Desert Rancheria Tribes (Pimas, Yumas, Papagos, Maricopas,…

  20. Arizona's Florence Project.

    ERIC Educational Resources Information Center

    Dallam, Elizabeth

    2001-01-01

    Describes the Florence Immigrant and Refugee Rights Project (Florence, Arizona) in which lawyers help individuals who are being detained in Florence. Explains that the project offers service to individuals at the detention center, helps children without guardians, and provides information to immigrant communities on their rights when arrested.…