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Theses and Dissertations

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Full-Text Articles in The Sun and the Solar System

Implications Of Magnetic Evolution On Coronal Loop Thermal Variation Prior To Solar Flares, Kara L. Kniezewski Mar 2025

Implications Of Magnetic Evolution On Coronal Loop Thermal Variation Prior To Solar Flares, Kara L. Kniezewski

Theses and Dissertations

Solar flares are intense bursts of electromagnetic radiation, which occur due to a rapid destabilization and reconnection of the magnetic field. While flares are a magnetic phenomena, very little attention has been paid to thermal conditions in the corona prior to flare onset. This study serves as a follow-on to Kniezewski et al., 2024, where the EUV emission from coronal loops was observed to vary substantially and without any coherence between channels before 53 off-limb flares. These variations suggest multiple mechanisms within the coronal magnetic field are responsible for heating fluctuations. Here, the 3D magnetic field is modeled using a …


On The Nature Of Low-Frequency Power Spectra In Solar Wind Turbulence, Mason Alden Dorseth Jul 2024

On The Nature Of Low-Frequency Power Spectra In Solar Wind Turbulence, Mason Alden Dorseth

Theses and Dissertations

An important challenge in the accurate estimation of power spectra of plasma fluctuations in the solar wind at very low frequencies is that it requires extremely long signals, which will necessarily contain a mixture of qualitatively different solar wind streams. This unavoidably affects the structure of the power spectra by conflating all these different properties into a single power spectrum. This work develops a conditional statistical analysis to accurately estimate the power spectrum at arbitrarily low frequencies for ``pure'' slow solar wind stream, based on estimated autocorrelation functions of signals excluding portions that do not satisfy the required conditions. The …


Studying The Conditions For Magnetic Reconnection In Solar Flares With And Without Precursor Flares, Seth H. Garland Mar 2021

Studying The Conditions For Magnetic Reconnection In Solar Flares With And Without Precursor Flares, Seth H. Garland

Theses and Dissertations

Forecasting of solar flares remains a challenge due to the limited understanding of the triggering mechanisms associated with magnetic reconnection, the primary physical phenomenon connected to these events. Consequently, methods continue to rely on the climatology of solar flare events as opposed to the underlying physics principles. Models of magnetic reconnection in the solar atmosphere places the null point of the reconnection within the corona. Though as of now the coronal magnetic field cannot be directly measured, the field is tied to the photospheric magnetic field, which can be. This study utilized data from the Solar Dynamics Observatory Helioseismic and …


Chronos Spacecraft With Chiron Probe: Exploration Of The Hydrosphere, Principle Satellites, Atmosphere, And Rings Of Uranus, Payton E. Pearson Sep 2020

Chronos Spacecraft With Chiron Probe: Exploration Of The Hydrosphere, Principle Satellites, Atmosphere, And Rings Of Uranus, Payton E. Pearson

Theses and Dissertations

A design reference mission using more modern technological innovations has been developed for exploration of the outer reaches of our Solar System, specifically Uranus and its system of satellites. This mission will utilize theoretical technologies mostly without regard to their current technological readiness level (TRL), though most systems have a TRL of at least 5. The primary innovations explored in this thesis are the new launch systems that provide far greater payload capacity potentially sent to anywhere in the Solar System, new Stirling-engine radioisotope thermoelectric generators (SRTGs), vastly improved data storage technologies, optimized satellite antenna relay of data using much …


Rapid Orbit Refinement Of Potential Near-Earth Objects And Recovery Of Nearly Lost Asteroids, Austin Lantz Caughey Jan 2016

Rapid Orbit Refinement Of Potential Near-Earth Objects And Recovery Of Nearly Lost Asteroids, Austin Lantz Caughey

Theses and Dissertations

The Minor Planet Center alerts researchers about potential discoveries of new Near-Earth Objects (NEOs) on their NEO Confirmation Page (NEOCP). Most of these are indeed previously unstudied objects, which must be studied very promptly while initial predictions of their motions are still accurate. My thesis project has focused on the observation of these bodies, and the submission of their measured positions to the MPC within a few hours of observation. Data has been obtained using the Skynet Robotic Telescope Network, including the R-COP telescope in Perth, Australia; the PROMPT 3 telescope in La Serena, Chile; and Yerkes Observatory in Williams …


Interdisciplinary Connections Between Science & Theatre, Jessica N. Dotson Jan 2015

Interdisciplinary Connections Between Science & Theatre, Jessica N. Dotson

Theses and Dissertations

Abstract

INTERDISCIPLINARY CONNECTIONS BETWEEN SCIENCE & THEATRE

Jessica Nicole Dotson

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Fine Arts at Virginia Commonwealth University.

Virginia Commonwealth University, 2015.

Major Director: Dr. Noreen C. Barnes, Director of Graduate Studies, Associate Professor of Theatre

In the 1990s, astronomer Peter Usher was searching for new ways to teach his introductory astronomy class at Pennsylvania State University. He began to engage his students by searching for astronomical connections from other disciplines. His focus was turned to the arts, especially the works of William Shakespeare. Usher found, while …


In-Situ And Simultaneous Measurements Of Size And Charge Distributions Of Dust On Mars: Instrumentation And Analysis, Praveen Kumar Srirama Jan 2007

In-Situ And Simultaneous Measurements Of Size And Charge Distributions Of Dust On Mars: Instrumentation And Analysis, Praveen Kumar Srirama

Theses and Dissertations

Martian dust characterization is important for minimizing the effects of abrasion, adhesion, corrosion, and damage to mission hardware, and also to reduce the effect on human health during future robotic and human exploratory missions. Characterizing the particle size and charge on Mars dust will help in the development of techniques for dust mitigation. Presently there is no miniature instrument which is capable of in-situ and real time measurements on Mars. In order to simultaneously analyze the particle size and charge of Mars dust, a Dust Particle Analyzer (DPA) has been developed and tested which is based on a Laser Doppler …


Prediction Of Flight-Level Radiation Hazards Due To Solar Energetic Protons, Matthew P. Sattler Mar 2006

Prediction Of Flight-Level Radiation Hazards Due To Solar Energetic Protons, Matthew P. Sattler

Theses and Dissertations

The radiation environment at aircraft altitudes is caused primarily by high-energy particles originating from outside the near-earth environment. These particles generally come from outside our solar system and are called galactic cosmic rays. Occasionally however, a transient solar event will also accelerate energetic protons toward the earth. If these protons reach the upper atmosphere, they produce secondary particles via collisions, resulting in increased radiation levels in the atmosphere. Air crews and electronic systems flying at high altitudes during one of these events are subjected to these increased levels of radiation which can result in health problems for personnel and soft …


Customization Of Discriminant Function Analysis For Prediction Of Solar Flares, Evelyn A. Schumer Mar 2005

Customization Of Discriminant Function Analysis For Prediction Of Solar Flares, Evelyn A. Schumer

Theses and Dissertations

This research is an extension to the research conducted by K. Leka and G. Barnes of the Colorado Research Associates Division, Northwest Research Associates, Inc. in Boulder, Colorado (CORA) in which they found no single photospheric solar parameter they considered could sufficiently identify a flare-producing active region (AR). Their research then explored the possibility a linear combination of parameters used in a multivariable discriminant function (DF) could adequately predict solar activity. The purpose of this research is to extend the DF research conducted by Leka and Barnes by refining the method of statistical discriminant analysis (DA) with the goal of …


Analysis Of Periodic Orbits About The Martian Moons By Continuation Techniques, Frank Luria Dec 1990

Analysis Of Periodic Orbits About The Martian Moons By Continuation Techniques, Frank Luria

Theses and Dissertations

From a few known periodic orbits of Phobos and Deimos, continuation techniques were used to find entire families of stable orbits. These techniques involved varying a parameter, the Hamiltonian, of the system and analyzing how the orbital behavior changed with the parameter. Floquet multipliers, for stability analysis, were also computed. AUTO86, a continuation/bifurcation software package, was used in this study. Artificial energy dissipation had to be added to the conservative Hamiltonian system to enable use of AUTO.


Realistic Orbits About The Martian Moons, Samuel R. Bryant Dec 1990

Realistic Orbits About The Martian Moons, Samuel R. Bryant

Theses and Dissertations

Orbits about the Martian moons, Phobos and Deimos, previously found to be stable by the Poincare surface of section technique in a restricted three- body system, were investigated with non-zero eccentricity of the moons added to the dynamics of the planar four-body system (Mars, moon sun, artificial satellite). Although not strictly applicable to this case, the surface of section technique was used to verify whether or not the previously found stable orbits were realistic when a real world perturbation was added to the system dynamics. The surface of section technique involves the numerical integration of several orbits with the same …