Confronting A Solar Irradiance Reconstruction With Solar And Stellar Data,
2012
National Center for Atmospheric Research
Confronting A Solar Irradiance Reconstruction With Solar And Stellar Data, Philip G. Judge, G. Wesley Lockwood, Richard R. Radick, Gregory W. Henry, Alexander I. Shapiro, Werner Schmutz, Charles Lindsey
Information Systems and Engineering Management Research Publications
Context. A recent paper by Shapiro and colleagues (2011, A&A, 529, A67) reconstructs spectral and total irradiance variations of the Sun during the holocene.
Aims. In this note, we comment on why their methodology leads to large (0.5%) variations in the solar TSI on century-long time scales, in stark contrast to other reconstructions which have ≲ 0.1% variations.
Methods. We examine the amplitude of the irradiance variations from the point of view of both solar and stellar data.
Results. Shapiro et al.’s large amplitudes arise from differences between the irradiances computed from models A and C of Fontenla and colleagues, …
Stability Of Phyllosilicates On Mars,
2012
University of Arkansas, Fayetteville
Stability Of Phyllosilicates On Mars, Patricia Gavin
Graduate Theses and Dissertations
This study investigates the stability of phyllosilicates on the surface of Mars through laboratory experiments and analysis of terrestrial analogs. Phyllosilicates are mostly found in the oldest Noachian terrains on Mars and hence hold clues to the planet's earliest aqueous and geologic history. Phyllosilicates relevant to Mars were heated up to ~1100°C for up to 24 hours and impacted with projectile velocities up to ~4.5 km/s. Heated samples were analyzed using x-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) spectroscopy in the near- (NIR, 1.0-2.5 µm) and mid-infrared (MIR, 5.0-15.0 µm) ranges. Impacted samples were also analyzed using Raman spectroscopy …
Orbital Periodicities Reflected In Ancient Surfaces Of Our Solar System And The Implications For A Record Of Early Life,
2012
University of Arkansas, Fayetteville
Orbital Periodicities Reflected In Ancient Surfaces Of Our Solar System And The Implications For A Record Of Early Life, Dixie Lee Androes
Graduate Theses and Dissertations
Uniformitarian processes, governed by invariant physical laws, remain the most reliable source for reconstructing the past. Driving many of the repetitive, predictable processes are the orbital dynamics of the Sun-Planet-Moon systems. Astronomical periodicities range from a few hours (tides) to thousands of years (Milankovitch). These periodicities, combined with geomorphic observations of planetary surfaces, constrain the time-dependent processes and allow for reconstruction of events and conditions favorable for sedimentary accumulations. This research suggests that seasonal sedimentary processes are dominant on Titan and Mars, and have played a significant role in the formation of ancient banded-iron formations (BIF's) on Earth.
Earth, Mars, …
Sodium Atoms In The Lunar Exotail: Observed Velocity And Spatial Distributions,
2012
California Institute of Technology
Sodium Atoms In The Lunar Exotail: Observed Velocity And Spatial Distributions, Michael R. Line, E. J. Mierkiewicz, R. J. Oliversen, J. K. Wilson, L. M. Haffner, F. L. Roesler
Physical Sciences - Daytona Beach
The lunar sodium tail extends long distances due to radiation pressure on sodium atoms in the lunar exosphere. Our earlier observations measured the average radial velocity of sodium atoms moving down the lunar tail beyond Earth (i.e., near the anti-lunar point) to be ∼12.5. km/s. Here we use the Wisconsin H-alpha Mapper to obtain the first kinematically resolved maps of the intensity and velocity distribution of this emission over a 15° × 15 ° region on the sky near the anti-lunar point. We present both spatially and spectrally resolved observations obtained over four nights bracketing new Moon in October 2007. …
The Ages And Metallicities Of Type Ia Supernova Host Galaxies From The Nearby Galaxies Supernova Search Program,
2012
Western Kentucky University
The Ages And Metallicities Of Type Ia Supernova Host Galaxies From The Nearby Galaxies Supernova Search Program, Suzanna Sadler
Mahurin Honors College Capstone Experience/Thesis Projects
We seek to better understand the physical constraints under which White Dwarf stars ultimately become Type Ia supernovae (SNe Ia), an important test of the robustness of these tools in precisely measuring Dark Energy, as the definite progenitor system still remains elusive. The host galaxy environments of Type Ia supernovae provide our best opportunity for constraining the mechanism(s) of SN Ia production, i.e., the stars involved and the incubation times (tied to stellar ages), and the sensitivity of SNe Ia to changes in the local metallicity. We have measured the ages and metallicities of approximately 60 galaxies from a sample …
Modeling Water Stability And Transport On Mars And Iapetus: Exploring Their Effects On Geomorphic And Atmospheric Processes,
2012
University of Arkansas, Fayetteville
Modeling Water Stability And Transport On Mars And Iapetus: Exploring Their Effects On Geomorphic And Atmospheric Processes, Edgard Giovanni Rivera-Valentin
Graduate Theses and Dissertations
The stability and transport of water on solid planetary surfaces strongly affects both atmospheric and surfaces processes. In this work, two bodies are specifically investigated where transport of water is relevant: Iapetus and Mars. Iapetus, an icy Kronian satellite, has a drastic albedo contrast on its surface and one of the darkest surfaces in the solar system. This extreme brightness contrast is suggested to occur via the transport of water ice from the leading hemisphere to the trailing hemisphere and the poles. Here a global heat and mass transfer model is developed for Iapetus in order to study the current …
Experimental Simulations Of Dark Slope Streaks On Mars,
2012
University of Arkansas, Fayetteville
Experimental Simulations Of Dark Slope Streaks On Mars, Kelly Howe
Graduate Theses and Dissertations
Martian slope streaks were first observed in Viking images but their formation still remains ambiguous. Martian slope streaks are currently occurring geological phenomenon on Mars, which requires any formation theory to be in agreement with Mar's current temperature and pressure conditions. Planar morphology of martian slope streaks suggest a potential fluvial formation, but current conditions on Mars are not conducive to water remaining liquid long enough to erode the surface. Debris flows, fluid stains and dry dust avalanches have all been previously cited as a potential formation mechanism for martian slope streaks. Recent experimental simulations indicate that a fluvial source …
Asteroid Retrieval Feasibility Study,
2012
California Institute of Technology
Asteroid Retrieval Feasibility Study, John Brophy, Fred Culick, Louis Friedman, Pedro Llanos, Et Al.
Publications
This report describes the results of a study sponsored by the Keck Institute for Space Studies (KISS) to investigate the feasibility of identifying, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the vicinity of the Earth by the middle of the next decade. The KISS study was performed by people from Ames Research Center, Glenn Research Center, Goddard Space Flight Center, Jet Propulsion Laboratory, Johnson Space Center, Langley Research Center, the California Institute of Technology, Carnegie Mellon, Harvard University, the Naval Postgraduate School, University of California at Los Angeles, University of California at Santa Cruz, University of Southern …
Phreatomagmatic Activity On The Moon: Possibility Of Pseudocraters At Mare Frigoris,
2012
University of Texas at El Paso
Phreatomagmatic Activity On The Moon: Possibility Of Pseudocraters At Mare Frigoris, Jose Humberto Garcia
Open Access Theses & Dissertations
The discovery of water on the Moon raises the possibility that lava-water, or phreatomagmatic, interactions have occurred on the lunar surface in the past. Such interactions may have formed pseudocraters, crater-like landforms that result from steam explosions that occur when lava flows come in contact with surface or near-surface water or ice. We present a study of Mare Frigoris, a volcanic plain just north of the Mare Imbrium impact basin on the Moon. Clusters of irregular, circular features on the basaltic lava flows in this area resemble pseudocrater fields in Iceland, and they are located in a region with inferred …
Characterization Of Thrust Faults On The Moon Using Fault Dynamics And 3d Visualizations,
2012
University of Texas at El Paso
Characterization Of Thrust Faults On The Moon Using Fault Dynamics And 3d Visualizations, Jaclyn Danielle Clark
Open Access Theses & Dissertations
Many small, lobate scarps, interpreted to be the surface traces of thrust faults, have been found all over Earth's moon by previous researchers. Fault dynamical calculations, assuming an initially completely molten Moon, have shown that these scarps can form due to compressional stresses that accumulate over time as the result of large-scale contraction of the Moon as it cooled. With high-resolution images from the Lunar Reconnaissance Orbiter Camera (LROC), previously undetected lobate scarps can be found globally and viewed at high resolution. By investigating these fault scarps, we can determine better constraints on the amount of crustal shortening and improve …
New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data,
2012
University of Texas at El Paso
New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data, Jonathan Arthur Meyer
Open Access Theses & Dissertations
Lava tubes have the potential to serve as a sustainable solution to long-term lunar habitation by providing protection from radiation and micrometeorite bombardment while potentially providing resources in the form of trapped water ice. They also pose compelling science targets in their own right. While the potential benefits of utilizing lunar lava tubes is clear, their discovery is less straightforward. Formation processes for lava tubes do not always result in a surface expression, making their discovery using remotely sensed imagery difficult. Furthermore, there is the potential for lava tubes to be covered by secondary lava flows, impact ejecta, or other …
Numerical Modeling Of Tectonics And Fault Activity Of Icy Satellites,
2012
University of Texas at El Paso
Numerical Modeling Of Tectonics And Fault Activity Of Icy Satellites, John Olgin
Open Access Theses & Dissertations
Enceladus, one of the satellites of Saturn, exhibits evidence of recent fault activity, which may be due to gravitational fluctuations, or tidal stresses, generated by its orbit around Saturn. Recent Cassini spacecraft observations of Enceladus reveal water-ice plume activity at the south polar region, originating from locations that correlate with four geologically young, linear fracture-like features, named the "tiger stripes". It is the goal of this investigation to determine the ideal geophysical and geological factors (e.g., fault depths, frictional coefficients, ice layer thickness, ocean layer thickness, tidal stress sources) that support fault activity on Enceladus. The core of this work …
Book Review: The International Atlas Of Mars Exploration: The First Five Decades: V.1: 1953 To 2003,
2012
Florida Institute of Technology
Book Review: The International Atlas Of Mars Exploration: The First Five Decades: V.1: 1953 To 2003, T. D. Oswalt
Publications
This document is Dr. Oswalt’s review of The International Atlas of Mars Exploration: the First Five Decades : V.1: 1953 to 2003 by Philip J. Stooke. Cambridge, 2012 359p, 0521765536 $140.00, 9780521765534 $140.00.
Analysis Of Solar Lyman-Alpha Backscatter Radiation In The Heliosphere,
2011
University of Alabama in Huntsville
Analysis Of Solar Lyman-Alpha Backscatter Radiation In The Heliosphere, Brian Fayock
Von Braun Symposium Student Posters
No abstract provided.
The Radioactive Moon,
2011
University of Alabama in Huntsville
The Radioactive Moon, Gaurish Nerurkar
Von Braun Symposium Student Posters
No abstract provided.
Chemical Abundances Of Red Giant Stars In The Globular Cluster M107 (Ngc 6171),
2011
Tennessee State University
Chemical Abundances Of Red Giant Stars In The Globular Cluster M107 (Ngc 6171), Julia O'Connell, Christian I. Johnson, Catherine A. Pilachowski, Geoffrey Burks
Mathematical Sciences Faculty Research
We present chemical abundances of Al and several Fe-Peak and neutron-capture elements for 13 red giant branch stars in the Galactic globular cluster NGC 6171 (M107). The abundances were determined using equivalent width and spectrum synthesis analyses of moderate-resolution ( R ∼ 15,000), moderate signal-to-noise ratio (〈S/N〉 ∼ 80) spectra obtained with the WIYN telescope and Hydra multifiber spectrograph. A comparison between photometric and spectroscopic effective temperature estimates seems to indicate that a reddening value of E(B - V) = 0.46 may be more appropriate for this cluster than the more commonly used value of E(B - V) = 0.33. …
Book Review: Exploring Mars: Chronicles From A Decade Of Discovery,
2011
Florida Institute of Technology
Book Review: Exploring Mars: Chronicles From A Decade Of Discovery, T. D. Oswalt
Publications
This document is Dr. Oswalt’s review of Exploring Mars : Chronicles from a Decade of Discovery by Scott Hubbard. Arizona, 2011 194p, 9780816521111 $45.00, 9780816528967 $17.95.
Abrupt Longitudinal Magnetic Field Changes In Flaring Active Regions,
2010
National Solar Observatory
Abrupt Longitudinal Magnetic Field Changes In Flaring Active Regions, G. J.D. Petrie, Jeffrey J. Sudol
Physics & Engineering Faculty Publications
No abstract provided.
Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks,
2010
Florida Institute of Technology
Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt
Publications
This document is Dr. Oswalt’s review of Stars Above, Earth Below : a Guide to Astronomy in the National Parks by Tyler Nordgren. Springer/Praxis, 2010 444p, 9781441916488 $29.95.
Noegenetic Io Monitoring Observernimo,
2010
University of Alabama in Huntsville
Noegenetic Io Monitoring Observernimo, William Daniels
Von Braun Symposium Student Posters
No abstract provided.
