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Articles 151 - 180 of 411

Full-Text Articles in The Sun and the Solar System

Sun-Like Stars Shed Light On Solar Climate Forcing, Philip G. Judge, Ricky Egeland, Gregory W. Henry Mar 2020

Sun-Like Stars Shed Light On Solar Climate Forcing, Philip G. Judge, Ricky Egeland, Gregory W. Henry

Information Systems and Engineering Management Research Publications

Recently published precise stellar photometry of 72 Sun-like stars obtained at the Fairborn Observatory between 1993 and 2017 is used to set limits on the solar forcing of Earth's atmosphere of ±4.5 W m−2 since 1750. This compares with the +2.2 ± 1.1 W m−2 IPCC estimate for anthropogenic forcing. Three critical assumptions are made. In decreasing order of importance they are: (a) most of the brightness variations occur within the average time series length of ≈17 yr; (b) the Sun seen from the ecliptic behaves as an ensemble of middle-aged solar-like stars; and (c) narrowband photometry in the Strömgren …


Mass Determinations Of The Three Mini-Neptunes Transiting Toi-125, Louise D. Nielsen, D. Gandolfi, D. J. Armstrong, J. S. Jenkins, M. Fridlund, N. C. Santos, F. Dai, V. Adibekyan, R. Luque, Jason H. Steffen, M. Esposito, F. Meru, S. Sabotta, E. Bolmont, D. Kossakowski, J. F. Otegi, F. Murgas, M. Stalport, F. Rodler, M. R. Diaz, N. T. Kurtovic, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, R. Allart, J. M. Almenara, D. Barrado, S. C.C. Barros Jan 2020

Mass Determinations Of The Three Mini-Neptunes Transiting Toi-125, Louise D. Nielsen, D. Gandolfi, D. J. Armstrong, J. S. Jenkins, M. Fridlund, N. C. Santos, F. Dai, V. Adibekyan, R. Luque, Jason H. Steffen, M. Esposito, F. Meru, S. Sabotta, E. Bolmont, D. Kossakowski, J. F. Otegi, F. Murgas, M. Stalport, F. Rodler, M. R. Diaz, N. T. Kurtovic, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, R. Allart, J. M. Almenara, D. Barrado, S. C.C. Barros

Physics & Astronomy Faculty Research

The Transiting Exoplanet Survey Satellite, TESS, is currently carrying out an all-sky search for small planets transiting bright stars. In the first year of the TESS survey, a steady progress was made in achieving the mission’s primary science goal of establishing bulk densities for 50 planets smaller than Neptune. During that year, the TESS’s observations were focused on the southern ecliptic hemisphere, resulting in the discovery of three mini-Neptunes orbiting the star TOI-125, a V = 11.0 K0 dwarf. We present intensive HARPS radial velocity observations, yielding precise mass measurements for TOI-125b, TOI-125c, and TOI-125d. TOI-125b has an orbital period …


On Possibility Of Binary Companion Of The Sun: A Serendipity Finding And Comparison With Uvs Model Of Solar System, Victor Christianto, Florentin Smarandache Jan 2020

On Possibility Of Binary Companion Of The Sun: A Serendipity Finding And Comparison With Uvs Model Of Solar System, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

While we completely understood that a binary dwarf companion of the Sun has not been accepted by majority of astronomers, allow us to present some new arguments, along with our own serendipitous encounter with such a binary companion of the Sun. We hope that the present note will be found useful for further investigations, in relation to Planet Nine and such a dwarf star companion of the Sun (sometimes dubbed as Nemesis). Nonetheless, this article is not an exhaustive review of such dwarf companion star theories.


A 3-Year Sample Of Almost 1,600 Elves Recorded Above South America By The Pierre Auger Cosmic-Ray Observatory, A. Aab, R. Engel, Gregory Snow, Pierre Auger Cosmic-Ray Observatory, 390 Co-Authors Jan 2020

A 3-Year Sample Of Almost 1,600 Elves Recorded Above South America By The Pierre Auger Cosmic-Ray Observatory, A. Aab, R. Engel, Gregory Snow, Pierre Auger Cosmic-Ray Observatory, 390 Co-Authors

Gregory Snow Publications

Elves are a class of transient luminous events, with a radial extent typically greater than 250 km, that occur in the lower ionosphere above strong electrical storms.We report the observation of 1,598 elves, from 2014 to 2016, recorded with unprecedented time resolution (100 ns) using the fluorescence detector (FD) of the Pierre Auger Cosmic-Ray Observatory. The Auger Observatory is located in the Mendoza province of Argentina with a viewing footprint for elve observations of 3 · 106 km2, reaching areas above the Pacific and Atlantic Oceans, as well as the Córdoba region, which is known for severe convective thunderstorms. Primarily …


Searching For The Common Suprathermal Power Law Tail In Parker Solar Probe's Isois Data, Asher S. Merrill Jan 2020

Searching For The Common Suprathermal Power Law Tail In Parker Solar Probe's Isois Data, Asher S. Merrill

Honors Theses and Capstones

Results from the Advanced Composition Explorer (ACE) and the Ulysses spacecraft suggested the existence of a pervasive power-law spectrum of suprathermal ions in the solar wind with a spectral index of -3/2. This distribution is of particular interest to humanity because the suprathermal ions it describes can serve as the seed population for large, destructive events that can harm ground- and air-based equipment. It has been suggested that various statistical mechanisms can produce the observed spectrum, however the underlying physical phenomena are not yet known. The spectrum of suprathermal ions is relatively unstudied closer to the Sun than 1 au. …


A Photometric Study Of The South Polar Terrain Of Enceladus, Bereket Daniel Mamo Jan 2020

A Photometric Study Of The South Polar Terrain Of Enceladus, Bereket Daniel Mamo

All Graduate Theses, Dissertations, and Other Capstone Projects

Saturn's moon, Enceladus, is a unique body in the Solar System. It is an icy world with ongoing geologic activity that spews out jets of ice particles, water vapor, and other gases from active tectonic fractures (called sulci) near its south pole. Emission from these jets is the dominant source of particles for Saturn's diffuse E ring, which envelops other icy satellites. The south polar fractures are also sources of tidally generated high heat flow. Accurate determination of this endogenic thermal output requires knowledge of the thermophysical properties of the surface, which are reliably estimated by modeling the photometric behavior …


Just A Bit Of Physics Can Tell So Much: A Unique Story Of The Start Of The Earth-Moon System, Fred J. Cadieu Jan 2020

Just A Bit Of Physics Can Tell So Much: A Unique Story Of The Start Of The Earth-Moon System, Fred J. Cadieu

Publications and Research

The start of the Earth-Moon system has been studied to show that this was an exceptionally violent event. One result was that Earth became the terrestrial planet with the highest average density. Another result was that Earth acquired enough mass and radioactive elements that it is expected to maintain a molten core region and magnetic field for the expected life of the Earth. Earth alone of the terrestrial planets was then able to develop plate tectonics as a long term energy release mechanism. The dipole magnetic field of the Sun reverses periodically, currently at the rate of about every 11 …


New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd Dec 2019

New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd

Branch Mathematics and Statistics Faculty and Staff Publications

It is widely known among the Frontiers of physics, that “sweeping under the rug” practice has been quite the norm rather than exception. In other words, the leading paradigms have strong tendency to be hailed as the only game in town. For example, renormalization group theory was hailed as cure in order to solve infinity problem in QED theory. For instance, a quote from Richard Feynman goes as follows: “What the three Nobel Prize winners did, in the words of Feynman, was "to get rid of the infinities in the calculations. The infinities are still there, but now they can …


Astrodynamics Of The Next Generation Space Weather Prediction Mission, Mark Herring Dec 2019

Astrodynamics Of The Next Generation Space Weather Prediction Mission, Mark Herring

Doctoral Dissertations and Master's Theses

Accurate prediction of the solar wind properties, interplanetary magnetic field direction and various space weather phenomena becomes ever more important as our dependence on Earth orbiting spacecraft increases. Different solar wind drivers can lead both to enhancements and losses of relativistic electrons in the outer radiation belts, thus posing a major risk to satellites. To further our understanding of the Sun’s impact on the near Earth space environment, as well as to provide predictive capabilities, a mission placing monitoring satellites in key orbits in the inner Solar System is being proposed. As part of that effort, the possibility of using …


An Investigation Of Metal Sulfides As The Source Of The Low Emissivity Anomaly On The Highlands Of Venus, Sara Taeko Port Dec 2019

An Investigation Of Metal Sulfides As The Source Of The Low Emissivity Anomaly On The Highlands Of Venus, Sara Taeko Port

Graduate Theses and Dissertations

Since its detection in the 1960s the source of the unusual radar emissivity signal seen on several highlands on Venus has long eluded researchers. Researchers have determined that a mineral with a high dielectric constant could explain the signal. Using a Venus simulation chamber, we experimentally investigated this enigma to build upon the candidate mineral list that has been compiled over the last several decades. We tested the stability of 8 different minerals and elements at two to three different temperature/pressure regimes in three different gas mixtures meant to simulate the conditions found on Venus for a period of no …


Exploring Planetary Surfaces With Remote Sensing, Donald R. Hood Nov 2019

Exploring Planetary Surfaces With Remote Sensing, Donald R. Hood

LSU Doctoral Dissertations

Aside from Earth, Mars is the most well-explored planetary body in our solar system. Much has been learned about its geologic past including a history of volcanism, ice ages, and potentially long-lasting liquid water. Much of this knowledge of Mars comes from remote observations of the surface and atmosphere from Mars-orbiting satellites. Such remote observations remain the only way to examine the entirety of Mars’ surface as rovers and landers can only examine small areas. The chapters of this work cover three projects that explore the surface of Mars through a variety of remote sensing methods.

In chapter 1, Gamma-ray …


Descriptive Astronomy I: The Solar System (Csu), Rosa Williams, Kimberly Shaw Oct 2019

Descriptive Astronomy I: The Solar System (Csu), Rosa Williams, Kimberly Shaw

Physics and Astronomy Grants Collections

This Grants Collection for Descriptive Astronomy I was created under a Round Thirteen ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Each collection contains the following materials:

  • Linked Syllabus
  • Initial Proposal
  • Final Report


On Newtonian Dynamics With A Variable Earth Mass: Geodetic Evidence And Its Implications On Pioneer Spacecraft Anomaly And Lageos Satellite, Victor Christianto, Florentin Smarandache Sep 2019

On Newtonian Dynamics With A Variable Earth Mass: Geodetic Evidence And Its Implications On Pioneer Spacecraft Anomaly And Lageos Satellite, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Around 3 decades ago, Jayant Narlikar & Halton Arp argued on possible variable mass hypothesis cosmology (VMH). In the meantime, the Earth expansion problem has attracted great interest, and recent study gives geodetic evidence that the Earth has been expanding, at least over the recent several decades. Therefore, in the present article discusses some interesting effects related to varying G, but here we argue that instead of varying G we can think of varying mass (M). Among other things we discuss receding planets from the Sun, calculation of Pioneer spacecraft anomaly as proposed by B.G. Sidharth, and also possible slight …


Adsorption Driven Regolith-Atmospheric Water Vapor Transfer On Mars: An Analysis Of Phoenix Tecp Data, Holly Nicole Farris Aug 2019

Adsorption Driven Regolith-Atmospheric Water Vapor Transfer On Mars: An Analysis Of Phoenix Tecp Data, Holly Nicole Farris

Graduate Theses and Dissertations

NASA’s Phoenix mission allowed for investigations of Martian diurnal water vapor cycles through the collection of temperature, relative humidity, and electric conductivity data by the Thermal and Electric Conductivity Probe (TECP) instrument. Using this data and previous experimental data, we propose a regolith-driven adsorption-desorption regime at the Phoenix landing site, where parameters intrinsic to the regolith are controlling localized relative humidity at the surface. To constrain these parameters, we model adsorption as a function of temperature and relative humidity across various Mars-relevant materials, defined by two layer-based adsorption theories: Langmuir (monolayer) and Brunauer-Emmett-Teller or BET (multilayer). Langmuir serves as an …


Decoding The History Of The Early Solar System Using Comet Volatile Compositions, Nathan Roth Jul 2019

Decoding The History Of The Early Solar System Using Comet Volatile Compositions, Nathan Roth

Dissertations

Understanding the evolution of the solar system, as well as its current volatile content, requires knowledge of the initial conditions present in the solar nebula. As some of the first objects to accrete in the solar nebula, cometary nuclei are among the most primitive remnants of solar system formation, and their present-day volatile composition likely reflects the composition and conditions where (and when) they formed. As such, the volatile compositions of cometary nuclei may serve as "fossils" of solar system formation. High-resolution near-infrared spectroscopy offers a valuable tool for sampling the primary volatile (i.e., ices subliming directly from the nucleus) …


Understanding Solar Activity During The Last 400 Years, Sam Q. Hollenbach May 2019

Understanding Solar Activity During The Last 400 Years, Sam Q. Hollenbach

Macalester Journal of Physics and Astronomy

The solar cycle has a profound effect on both terrestrial and extra-terrestrial operations. Understanding the history of the solar cycle is necessary for studying long term trends, however older data is difficult to calibrate due to the sparsity of observations. In this paper we propose a new method for calibrating sunspot number data that does not rely on observational overlap. Initial testing shows promise in this method’s success, though more work must be done to ensure calibration consistency across all observers.


Induced Magnetic Dipole On Jupiter’S Moon Europa, Luke Francis, Michele Zanolin Apr 2019

Induced Magnetic Dipole On Jupiter’S Moon Europa, Luke Francis, Michele Zanolin

Student Works

Physics can have some of the most unique and extraordinary applications of basic principles applied on a larger scale. This paper will explore the properties of induced magnetic dipoles and will examine this phenomenon directly from Jupiter's moon, Europa. These properties will be used to determine if there is liquid water beneath its icy surface and how this conclusion was verified. This will be accomplished using the concepts of magnetic dipoles and induced currents. Recent missions have also revealed estimates of the depth of Europa's subsurface ocean. There have been many measurements taken of Europa's magnetic field, and they are …


Pluto’S Classification, Saylor Bane Apr 2019

Pluto’S Classification, Saylor Bane

Classical Conversations

Nearly 100 years ago, astronomers hypothesized that a large celestial object, nicknamed “Planet X,” must be pulling two planets out of their typical heliocentric orbits. After racing to find this celestial object for decades, Clyde Tombaugh found a faint sparkling speck of light and announced that he had finally discovered Planet X. Later, Tombaugh’s discovery was named Pluto and immediately deemed the ninth planet. As technology improved, many other celestial objects were found lurking in the outer limits of the solar system leading to worldwide confusion over which were official planets. To solve the problem, the International Astronomical Union (IAU) …


Galactic Preservation And Beyond: A Framework For Protecting Cultural, Natural, And Scientific Heritage In Space, Matthew Rosendahl Mar 2019

Galactic Preservation And Beyond: A Framework For Protecting Cultural, Natural, And Scientific Heritage In Space, Matthew Rosendahl

William & Mary Environmental Law and Policy Review

In July 2017, Moon Express, a private spaceflight company, announced plans to build an outpost on the South Pole of the Moon by 2020. The goal? To mine the Moon for minerals and water that could then be sold for profit. Indeed, the Moon has been found to possess resources with lucrative uses, both in space and here on Earth. The potential for huge rewards has incentivized several private and governmental actors to launch planned expeditions to the Moon, with China becoming the third nation to land a spacecraft there in 2013. Both China and India have since announced plans …


Measurement Of Solar Spectral Irradiance And Surface Ozone At Carrollton, Georgia, Usa, During The Great American Eclipse On 21 August 2017, Kirthi Tennakone, L Ajith Desilva, Charles A. Zander*, Shea Rose, Austin B. Kerlin Mar 2019

Measurement Of Solar Spectral Irradiance And Surface Ozone At Carrollton, Georgia, Usa, During The Great American Eclipse On 21 August 2017, Kirthi Tennakone, L Ajith Desilva, Charles A. Zander*, Shea Rose, Austin B. Kerlin

Georgia Journal of Science

Measurements conducted at the University of West Georgia, Carrollton, Georgia, during the time of the solar eclipse of 21st August 2017 demonstrated that the integrated spectral irradiance in defined wavelength ranges in the ultraviolet and visible calculated as a fraction of the total irradiance reached a minimum at maximum obscuration of the Sun, whereas in an infrared range it was maximum. The method of analysis adopted supports the view that the changes in spectral irradiance during highly obscured partial phases is a consequence of limb darkening. In a surface ozone measurement, a minimum in ozone concentration occurred 30 +_ …


Engaging The Greater Lafayette Community In A Journey Through The Earth Sciences: Purdue’S Eaps Earth Science Passport Day Event, Dara Laczniak, Bradley Garczynski Mar 2019

Engaging The Greater Lafayette Community In A Journey Through The Earth Sciences: Purdue’S Eaps Earth Science Passport Day Event, Dara Laczniak, Bradley Garczynski

Engagement & Service-Learning Summit

No abstract provided.


The Limited Reign Of Saturn's Rings, Laurence A. Marschall Mar 2019

The Limited Reign Of Saturn's Rings, Laurence A. Marschall

Physics and Astronomy Faculty Publications

Saturn’s rings—stretching tens of thousands of miles above its equator but no more than a few hundred yards thick—mark an ancient debris field of orbiting ice shards, the remains of a moon-sized object that strayed too close and was torn to pieces by Saturn’s intense gravitation. Astronomers have debated when the rings formed and how long they will stay in orbit. Recent observations from large, land-based telescopes and orbiting spacecraft reveal that Saturn’s rings are remarkably young and are dissipating at a rapid rate. [excerpt]


Applications Of Information Theory In Solar And Space Physics, Jay R. Johnson, Simon Wing Feb 2019

Applications Of Information Theory In Solar And Space Physics, Jay R. Johnson, Simon Wing

Faculty Publications

Characterizing and modeling processes at the sun and space plasma in our solar system are difficult because the underlying physics is often complex, nonlinear, and not well understood. The drivers of a system are often nonlinearly correlated with one another, which makes it a challenge to understand the relative effects caused by each driver. However, entropy-based information theory can be a valuable tool that can be used to determine the information flow among various parameters, causalities, untangle the drivers, and provide observational constraints that can help guide the development of the theories and physics-based models. We review two examples of …


Astronomy For Educators, Daniel E. Barth Jan 2019

Astronomy For Educators, Daniel E. Barth

Open Educational Resources

Astronomy for Educators provides new and accomplished K-12 instructors with concepts and projects for low-cost, high-impact STEM classroom instruction that is built around the National Academies National Research Council's K-12 Framework for Science Education.


Ua66/11/1 Ogden College Of Science & Engineering Physics & Astronomy Publications, Wku Archives Jan 2019

Ua66/11/1 Ogden College Of Science & Engineering Physics & Astronomy Publications, Wku Archives

WKU Archives Collection Inventories

Publications by and about the Department of Physics and Astronomy.


The Dark Sky Character Of Archaeological Landscapes: Cultural Meaning And Conservation Strategies, Frank Prendergast Jan 2019

The Dark Sky Character Of Archaeological Landscapes: Cultural Meaning And Conservation Strategies, Frank Prendergast

Book/Book Chapter

This paper presents the first ever study of light pollution at selected Irish prehistoric archaeological landscapes. The concepts of cosmology and landscape are first briefly described and followed by a summary of early human settlement of the island. Building on this, the extant corpus of early prehistoric megalithic burial tombs is illustrated to show their contrasting distribution patterns and typology. Analysis of tomb locations using nearest-neighbour statistical methods reveals evidence of intentional clustering. Further geo-statistical analysis identifies the geographical locations and the density ranking of these nucleated clusters - a feature especially evident in the passage tomb tradition on this …


Ua66/12 Ogden College Of Science & Engineering Hardin Planetarium, Wku Archives Jan 2019

Ua66/12 Ogden College Of Science & Engineering Hardin Planetarium, Wku Archives

WKU Archives Collection Inventories

Records created by and about the Hardin Planetarium.


The Undeniable Attraction Of Lunar Swirls, Dany Waller Jan 2019

The Undeniable Attraction Of Lunar Swirls, Dany Waller

Posters-at-the-Capitol Presentations

Lunar swirls are complex patterns on the Moon with distinct brightness signatures and magnetic characteristics. Current research has suggested that the formation of lunar swirls relies on local magnetic fields to shield impinging solar wind, based on a shift in electromagnetic wavelength peaks related to solar radiation and space weathering. Our research combined recent models and methods to characterize these anomalies at the surface of the Moon, exploring the effects of field strength and position. We have produced a high resolution map of a famous swirl named Reiner Gamma using magnetic dipole modeling. These maps and models are considered when …


The Search For Microbial Martian Life And American Buddhist Ethics, Daniel S. Capper Jan 2019

The Search For Microbial Martian Life And American Buddhist Ethics, Daniel S. Capper

Faculty Publications

Multiple searches hunt for extraterrestrial life, yet the ethics of such searches in terms of fossil and possible extant life on Mars have not been sufficiently delineated. In response, in this essay I propose a tripartite ethic for searches for microbial Martian life that consists of default nonharm toward potential living beings, default nonharm to the habitats of potential living beings, but also responsible, restrained scientific harvesting of some microbes in limited transgression of these default nonharm modes. Although this multifaceted ethic remains secular and hence adaptable to space research settings, it arises from both a qualitative analysis of authoritative …


Electron Model Based On Helmholtz’S Electron Vortex Theory & Kolmogorov’S Theory Of Turbulence, Florentin Smarandache, Victor Christianto, Robert Neil Boyd Jan 2019

Electron Model Based On Helmholtz’S Electron Vortex Theory & Kolmogorov’S Theory Of Turbulence, Florentin Smarandache, Victor Christianto, Robert Neil Boyd

Branch Mathematics and Statistics Faculty and Staff Publications

In this paper, we explore a new electron model based on Helmholtz’s electron vortex and Kolmogorov theory of turbulence. We also discuss a new model of origination of charge and matter.