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Shape Model Of Potentially Hazardous Asteroid 1981 Midas From Radar And Lightcurve Observations, Riley McGlasson 2020 Macalester College

Shape Model Of Potentially Hazardous Asteroid 1981 Midas From Radar And Lightcurve Observations, Riley Mcglasson

Macalester Journal of Physics and Astronomy

We report observations of potentially hazardous, Apollo-class asteroid 1981 Midas, which passed 0.090 au from Earth (35 lunar distances) on March 21, 2018. During this close approach, Midas was observed by radar both from the Arecibo Observatory on March 21 through 25 (five nights), and from NASA's Goldstone Deep Space Communications Complex on March 19 and 21. These radar observations yielded one-dimensional continuous-wave spectra and two-dimensional delay-Doppler images. In addition, there have been optical lightcurve observations of Midas during four apparitions (1987, 1992, 2004, and 2018), which showed a rotation period of 5.22 hours. Midas has an ...


A Search For Pulsars Towards The Galactic Center, Jacob W. Hetrick, Kunal Mooley, Preshanth Jagannathan 2020 Macalester College

A Search For Pulsars Towards The Galactic Center, Jacob W. Hetrick, Kunal Mooley, Preshanth Jagannathan

Macalester Journal of Physics and Astronomy

We present observations from two separate methods for observing the Galactic Center in an attempt to characterize its pulsar and neutron star populations. A persistent puzzle of the past 20 years has been the lack of pulsar detections towards the Galactic Center, specifically within a few parsecs of the central supermassive black hole Sgr A*. This object is bright in the total intensity of its polarized emission, but is very weakly linearly polarized. We take advantage of these circumstances in an experimental search technique where we utilize the Faraday effect in an attempt to detect high rotation measure (RM) point ...


Modeling Scavenging For A Hydraulic Free-Piston Engine, Nathan Davies 2020 Macalester College

Modeling Scavenging For A Hydraulic Free-Piston Engine, Nathan Davies

Macalester Journal of Physics and Astronomy

The hydraulic free-piston engine at the University of Minnesota offers a solution to improve the hydraulic efficiency and reduce emission output of off-road vehicles. We developed a MATLAB Simulink model to track the pressure, temperature, and mass profile of the fuel within the cylinder during operation. By varying different initial conditions of our model, we found that a higher intake manifold pressure and larger bottom dead center location results in higher scavenging efficiency. These results can be used to improve the controller of this engine and better maintain stable operation.


Band Extension And Possible Ridge Compression On Europa, Sarah Chinski 2020 Macalester College

Band Extension And Possible Ridge Compression On Europa, Sarah Chinski

Macalester Journal of Physics and Astronomy

Jupiter's icy moon Europa has captivated and perplexed the scientific community since the discovery of its global liquid water ocean. Over the course of several missions to the Jovian system, high-resolution observations of Europa have determined that there are spreading zones where new crust is created, similar to the mid-ocean spreading tectonic process we observe on Earth. These features, known as bands, have symmetric hills and valleys, indicating brief events of activity where material from the interior is exuded through a central crack, and solidifies on both sides, creating two positive topography. Recently, Europan scientists have been questioning how ...


Electrical Measurement Of Sram Cell Variation And Sensitivity To Singe-Event Upsets By Low-Energy Protons, James M. Cannon 2020 Macalester College

Electrical Measurement Of Sram Cell Variation And Sensitivity To Singe-Event Upsets By Low-Energy Protons, James M. Cannon

Macalester Journal of Physics and Astronomy

With the rise of the transistor in the 1970s, electronics shifted from analog circuitry, where values are stored on a continuum, to digital, in which ones and zeros are the law of the land. Transistors, as a class circuit element, can be affected by radiation and cosmic rays which then cause temporary or permanent failures, depending on the specifics of the situation. On Earth, this poses little risk with all electronics shielded by the magnetosphere, however for space bound electronics, the risks from these extraterrestrial particles are not so negligible. The first step in designing a mission to be able ...


Design And Modal Analysis Of An Ultra-Wideband Receiver For Green Bank Observatory, Alyssa Bulatek 2020 Macalester College

Design And Modal Analysis Of An Ultra-Wideband Receiver For Green Bank Observatory, Alyssa Bulatek

Macalester Journal of Physics and Astronomy

The next generation of radio receivers for astronomy will be marked by tenfold improvements in sensitivity. These sensitive receivers will be useful for the detection of broadband fast radio bursts and other transients as well as the efficient discovery of radio recombination lines among many other scientific pursuits. One contribution to these improvements is an increase to decade receiver bandwidths. The Green Bank Observatory (GBO) is currently in the process of fabricating a new ultra-wideband (UWB; 0.7 to 4.2 GHz) receiver for the Green Bank Telescope (GBT). The UWB receiver will be used by the North American Nanohertz ...


Alfalfa Harvest: Hi Imaging And 3d Modeling Of Candidate Local Group Dwarf Galaxies, Lilly Bralts-Kelly, Susie Paine, Elizabeth A. K. Adams, John M. Cannon 2020 Macalester College

Alfalfa Harvest: Hi Imaging And 3d Modeling Of Candidate Local Group Dwarf Galaxies, Lilly Bralts-Kelly, Susie Paine, Elizabeth A. K. Adams, John M. Cannon

Macalester Journal of Physics and Astronomy

Isolated neutral hydrogen (HI) clouds, or "ultra-compact high-velocity clouds" (UCHVCs), form a small subset of detections by the Arecibo Legacy Fast ALFA (ALFALFA) blind extragalactic survey. These systems, if located within ~1 Mpc, would populate the lowest-mass end of the HI mass function. Subsequent optical imaging has revealed that some of these UCHVCs harbor associated (thought sparse) stellar populations, suggesting that they may be some of the most extreme galaxies known in the Local Volume, with properties akin to ultra-faint dwarf galaxies but with significant neutral gas reservoirs. In this work, we investigate the neutral hydrogen properties of six UCHVC ...


Leoncino And Ugc 5186, Josh Bartz 2020 Macalester College

Leoncino And Ugc 5186, Josh Bartz

Macalester Journal of Physics and Astronomy

AGC 198691 is commonly known as the Leoncino Dwarf and is one of the most metal poor galax- ies known. An Arecibo observation in 2011 first suggested that Leoncino could be gravitationally interacting with its neighbor UGC 5186. In this paper new VLA data is used to examine the H I com- ponent of both galaxies to determine their gravitational relationship. Although the VLA could not confirm intragalactic gas seen by Aricebo, the H I density and velocity components are strong indirect evidence of gravitational interaction. UGC 5186 has a large gaseous arm reaching in the direction of Leoncino. Additionally ...


Congressional Committee Resources On Space Policy During The 115th Congress (2017-2018): Providing Context And Insight Into Us Government Space Policy, Bert Chapman 2020 Purdue University

Congressional Committee Resources On Space Policy During The 115th Congress (2017-2018): Providing Context And Insight Into Us Government Space Policy, Bert Chapman

Libraries Faculty and Staff Presentations

Article 1 of the US Constitution assigns the US Congress numerous responsibilities. These include creating new laws, revising existing laws, funding government programs, and conducting oversight of these programs' performance. Oversight of US Government agency space policy programs is executed by various congressional space policy committees including the House and Senate Science Committees, Armed Services, and Appropriations Committees. These committees conduct many public hearings on space policy, which invite expert witnesses to testify on US space policy programs and feature debate on the strengths and weaknesses of these programs. Documentation produced by these committees is widely available to the public ...


Water On Mars—A Literature Review, Mohammad Nazari-Sharabian, Mohammad Aghababei, Moses Karakouzian, Mehrdad Karami 2020 University of Nevada, Las Vegas

Water On Mars—A Literature Review, Mohammad Nazari-Sharabian, Mohammad Aghababei, Moses Karakouzian, Mehrdad Karami

Civil & Environmental Engineering and Construction Faculty Publications

To assess Mars’ potential for both harboring life and providing useable resources for future human exploration, it is of paramount importance to comprehend the water situation on the planet. Therefore, studies have been conducted to determine any evidence of past or present water existence on Mars. While the presence of abundant water on Mars very early in its history is widely accepted, on its modern form, only a fraction of this water can be found, as either ice or locked into the structure of Mars’ plentiful water-rich materials. Water on the planet is evaluated through various evidence such as rocks ...


Mineral-Surface Chemistry Of Hydroxyapatite And Urea-Rich Solutions, Estefania Garcia 2020 Kennesaw State University

Mineral-Surface Chemistry Of Hydroxyapatite And Urea-Rich Solutions, Estefania Garcia

Master of Science in Chemical Sciences Theses

On this planet the development of life requires six essential elements: C, H, O, N, P, and S. These elements are present in gaseous form, with the exception of phosphorus, which is primarily found in solid mineral sources. Phosphorus in biological systems is significant through its involvement in metabolic functions (e.g., Coenzyme A), cell structure (i.e., phospholipid membranes), and genetic storage/transfer (i.e., phosphodiester bonds in DNA and RNA). However, an ambiguity remains with the assimilation of phosphorus in biological systems, caused by its habitual presence in insoluble phosphate mineral sources. Recent research has found that insoluble ...


Dust Condensation In Evolving Discs And The Composition Of Planetary Building Blocks, Min Li, Shichun Huang, Michail I. Petaev, Zhaohuan Zhu, Jason H. Steffen 2020 University of Nevada, Las Vegas

Dust Condensation In Evolving Discs And The Composition Of Planetary Building Blocks, Min Li, Shichun Huang, Michail I. Petaev, Zhaohuan Zhu, Jason H. Steffen

Physics & Astronomy Faculty Publications

Partial condensation of dust from the Solar nebula is likely responsible for the diverse chemical compositions of chondrites and rocky planets/planetesimals in the inner Solar system. We present a forward physical–chemical model of a protoplanetary disc to predict the chemical compositions of planetary building blocks that may form from such a disc. Our model includes the physical evolution of the disc and the condensation, partial advection, and decoupling of the dust within it. The chemical composition of the condensate changes with time and radius. We compare the results of two dust condensation models: one where an element condenses ...


Harbingers Of Exotic Transients: The Electromagnetic Follow-Up Of Gravitational-Wave Transients & Transient Rates, Deep Chatterjee 2020 University of Wisconsin-Milwaukee

Harbingers Of Exotic Transients: The Electromagnetic Follow-Up Of Gravitational-Wave Transients & Transient Rates, Deep Chatterjee

Theses and Dissertations

Gravitational waves (GWs) provide a unique view of the universe. They directly probe the extreme gravity and extreme matter of compact objects like black holes (BHs) and neutron stars (NSs) which is not always possible from traditional electromagnetic (EM) wave astronomy. The cataclysmic coalescence of compact object binaries is one of the loudest individual sources of GWs that can be detected by the Laser Interferometer Gravitational wave Observatory (LIGO) and the Virgo Observatory. If one of the component is a NS, there is a possibility that the merger is bright in the EM spectrum. The relativistic astrophysics could launch a ...


Neusch Automated Filter System: A Custom-Designed Photo-Filter Switching Apparatus For Embry-Riddle’S 1 Meter Telescope, Tyler Neusch 2020 Embry-Riddle Aeronautical University

Neusch Automated Filter System: A Custom-Designed Photo-Filter Switching Apparatus For Embry-Riddle’S 1 Meter Telescope, Tyler Neusch

PhD Dissertations and Master's Theses

The one-meter telescope on the roof of Embry-Riddle’s College of Arts and Sciences building in Daytona Beach, FL is an advanced piece of technology supporting education and public outreach. One part of this telescopic system is a custom-made Cassegrain Instrument Mount. This one-of-a-kind mount allows for multiple scientific instruments to be simultaneously mounted to the telescope. However, its mechanical layout prevents the use of a traditional device known as a filter wheel.

Filter wheels store multiple photo-filters each capable of filtering out all but certain wavelengths of light for use with a CCD camera. Therefore, a filter wheel allows ...


Formation Pathways In Brightest Cluster Galaxies: Measuring The Distribution Of Ages, Metallicities, And Hydrodynamics Of Stellar Populations, Priscilla E. Holguin West 2020 California Polytechnic State University, San Luis Obispo

Formation Pathways In Brightest Cluster Galaxies: Measuring The Distribution Of Ages, Metallicities, And Hydrodynamics Of Stellar Populations, Priscilla E. Holguin West

Physics

Brightest Cluster Galaxies (BCGs) are the most massive galaxies in the local universe and have had the full age of the universe to build. This makes their formation and evolution history particularly interesting as they offer a glimpse at potential evolutionary pathways for younger systems. We present the radial profile of ages, metallicities, and preliminary classification of companions to 23 BCGs observed using the SparsePak instrument on WIYN by running the STARLIGHT stellar population synthesis models. This analysis of the BCGs’ stellar populations is done by separating each BCG into different regions, and preliminary results of the stellar populations for ...


Discovering New Strong Gravitational Lenses In The Desi Legacy Imaging Surveys, Xiaosheng Huang, Christopher Storfer, A. Gu, V. Ravi, A. Pilon, W. Sheu, R. Venguswamy, S. Bankda, A. Dey, M. Landriau, D. Lang, A. Meisner, J. Moustakas, A. D. Myers, R. Sajith, E. F. Schlafly, D. J. Schlegel 2020 University of San Francisco

Discovering New Strong Gravitational Lenses In The Desi Legacy Imaging Surveys, Xiaosheng Huang, Christopher Storfer, A. Gu, V. Ravi, A. Pilon, W. Sheu, R. Venguswamy, S. Bankda, A. Dey, M. Landriau, D. Lang, A. Meisner, J. Moustakas, A. D. Myers, R. Sajith, E. F. Schlafly, D. J. Schlegel

Physics and Astronomy

We have conducted a search for new strong gravitational lensing systems in the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys’ Data Release 8. We use deep residual neural networks, building on previous work presented in Huang et al. (2020). These surveys together cover approximately one third of the sky visible from the northern hemisphere, reaching a z-band AB magnitude of ∼ 22.5. We compile a training sample that consists of known lensing systems as well as non-lenses in the Legacy Surveys and the Dark Energy Survey. After applying our trained neural networks to the survey data, we visually inspect and ...


Towards Gross-Pitaevskiian Description Of Solar System & Galaxies, Florentin Smarandache, Victor Christianto, Yunita Umniyati 2020 University of New Mexico

Towards Gross-Pitaevskiian Description Of Solar System & Galaxies, Florentin Smarandache, Victor Christianto, Yunita Umniyati

Mathematics and Statistics Faculty and Staff Publications

In this paper, we argue that Gross-Pitaevskii model can be a more complete description of both solar system and spiral galaxies, especially taking into account the nature of chirality and vortices in galaxies. We also hope to bring out some correspondence among existing models, e.g., the topological vortex approach, Burgers equation in the light of KAM theory, and the Cantorian Navier-Stokes approach. We hope further investigation can be done around this line of approach.


Determining The Rotational And Orbital Velocities Of Objects In The Solar System, Mark Jones 2020 East Tennessee State University

Determining The Rotational And Orbital Velocities Of Objects In The Solar System, Mark Jones

Undergraduate Honors Theses

Astronomers have been observing the night sky for many centuries to establish a better understanding for our universe and solar system. As part of their observations, astronomers characterize celestial bodies by fundamental properties such as mass, motion, and composition in order to provide further insight about the objects in question. As technology and science have evolved, the methods for measuring these properties have become more precise and accurate. One such methodology is known as spectroscopy, and it is a significant tool for observational astronomy. In this paper, we shall describe how we used astronomical spectroscopy to determine orbital and rotational ...


Analytic Exoplanet Transit Analysis, And Investigation Into Wasp, Kepler, And Qatar Systems, Colan Gulla 2020 College of the Holy Cross

Analytic Exoplanet Transit Analysis, And Investigation Into Wasp, Kepler, And Qatar Systems, Colan Gulla

College Honors Program

In this paper we analyze exoplanet transit data. First, we discuss an analytical method of assessing the data similar to the one derived in Agol & Mandel, 20021. The time series photometric data for transits used in this paper was downloaded from the NASA Exoplanet Archive. Similar data was also extracted from the Exoplanet Transit Database for analysis. We use a formula for relative flux from Agol & Mandel, 20021 to study the specific transit systems of WASP 1b, WASP 12b, Kepler 1, Qatar 1b and TRES-1b. The formula for relative flux is fit to a set of photometric data ...


Design And Construction Of A Computer Controlled Astronomical Spectropolarimeter, Jacob Marchio 2020 University of Maine

Design And Construction Of A Computer Controlled Astronomical Spectropolarimeter, Jacob Marchio

Honors College

A theoretical description of a simple optical train, modulated signal based spectropolarimeter is discussed. The design includes, after the telescope optical tube (in this case, a 9.25” Schmidt Cassegrain), a rotating quarter waveplate (compensator), a fixed linear polarizer (analyzer), and transmission grating of 100l/mm, with a ZWO ASI290mm astronomical camera. The practical constraints on implementing such an instrument are discussed, and the construction of the spectropolarimeter is detailed, including the necessary optics, optomechanics, and electromechanics. The rotation and recording of the rotating compensator is facilitated by a motorized connection with proportional feedback control, and the uncertainty in measuring ...


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