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Pluto’S Classification, Saylor Bane 2019 Southeastern University - Lakeland

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 ...


Recent Evolution Of The Eta Carinae Supernova Imposter System, Greta L. Helmel 2019 Macalester College

Recent Evolution Of The Eta Carinae Supernova Imposter System, Greta L. Helmel

Physics and Astronomy Honors Projects

The supernova imposter Eta Carinae and its surrounding Homunculus reflection nebula have been of great interest for the last several decades. As the most massive star known in our Galaxy, this object is of particular importance in understanding high mass loss episodes and final stages in the evolution of other similarly massive stars in the later stages of their lives. Observations using the STIS CCD Instrument have been taken over the past 20 years for both the central star and the Homunculus as part of the Hubble Space Telescope (HST) Treasury Program on Eta Carinae. Recent changes in the spectra ...


Still Missing Dark Matter: Kcwi High-Resolution Stellar Kinematics Of Ngc1052-Df2, Shany Danieli, Pieter van Dokkum, Charlie Conroy, Roberto Abraham, Aaron Romanowsky 2019 Yale University

Still Missing Dark Matter: Kcwi High-Resolution Stellar Kinematics Of Ngc1052-Df2, Shany Danieli, Pieter Van Dokkum, Charlie Conroy, Roberto Abraham, Aaron Romanowsky

Faculty Publications

The velocity dispersion of the ultra diffuse galaxy NGC1052-DF2 was found to be σgc = 7.8 +5.2/-2.2 km s−1, much lower than expected from the stellar mass–halo mass relation and nearly identical to the expected value from the stellar mass alone. This result was based on the radial velocities of 10 luminous globular clusters that were assumed to be associated with the galaxy. A more precise measurement is possible from high-resolution spectroscopy of the diffuse stellar light. Here we present an integrated spectrum of the diffuse light of NGC1052-DF2 obtained with the Keck Cosmic Web ...


Extreme Chemical Abundance Ratio Suggesting An Exotic Origin For An Ultradiffuse Galaxy, Ignacio Martín-Navarro, Aaron Romanowsky, Jean Brodie, Anna Ferr´e-Mateu, Adebusola Alabi, Duncan Forbes, Margarita Sharina, Alexa Villaume, Viraj Pandya, David Martinez-Delgado 2019 University of California Observatories

Extreme Chemical Abundance Ratio Suggesting An Exotic Origin For An Ultradiffuse Galaxy, Ignacio Martín-Navarro, Aaron Romanowsky, Jean Brodie, Anna Ferr´E-Mateu, Adebusola Alabi, Duncan Forbes, Margarita Sharina, Alexa Villaume, Viraj Pandya, David Martinez-Delgado

Faculty Publications

Ultradiffuse galaxies (UDGs) are a population of extended galaxies but with relatively low luminosities. The origin of these objects remains unclear, largely due to the observational challenges of the low surface brightness Universe. We present here a detailed stellar population analysis of a relatively isolated UDG, DGSAT I, based on spectroscopic data from the Keck Cosmic Web Imager integral field unit. The star formation history of DGSAT I seems to be extended, with a mean luminosity-weighted age of ∼3 Gyr, in agreement with previous photometric studies. However, we find a very high [Mg/Fe] abundance ratio, which is extreme even ...


Still Missing Dark Matter: Kcwi High-Resolution Stellar Kinematics Of Ngc1052-Df2, Shany Danieli, Pieter van Dokkum, Charlie Conroy, Roberto Abraham, Aaron J. Romanowsky 2019 Yale University

Still Missing Dark Matter: Kcwi High-Resolution Stellar Kinematics Of Ngc1052-Df2, Shany Danieli, Pieter Van Dokkum, Charlie Conroy, Roberto Abraham, Aaron J. Romanowsky

Aaron J. Romanowsky

The velocity dispersion of the ultra diffuse galaxy NGC1052-DF2 was found to be σgc = 7.8 +5.2/-2.2 km s−1, much lower than expected from the stellar mass–halo mass relation and nearly identical to the expected value from the stellar mass alone. This result was based on the radial velocities of 10 luminous globular clusters that were assumed to be associated with the galaxy. A more precise measurement is possible from high-resolution spectroscopy of the diffuse stellar light. Here we present an integrated spectrum of the diffuse light of NGC1052-DF2 obtained with the Keck Cosmic Web ...


Extreme Chemical Abundance Ratio Suggesting An Exotic Origin For An Ultradiffuse Galaxy, Ignacio Martín-Navarro, Aaron J. Romanowsky, Jean P. Brodie, Anna Ferr´e-Mateu, Adebusola Alabi, Duncan A. Forbes, Margarita Sharina, Alexa Villaume, Viraj Pandya, David Martinez-Delgado 2019 University of California Observatories

Extreme Chemical Abundance Ratio Suggesting An Exotic Origin For An Ultradiffuse Galaxy, Ignacio Martín-Navarro, Aaron J. Romanowsky, Jean P. Brodie, Anna Ferr´E-Mateu, Adebusola Alabi, Duncan A. Forbes, Margarita Sharina, Alexa Villaume, Viraj Pandya, David Martinez-Delgado

Aaron J. Romanowsky

Ultradiffuse galaxies (UDGs) are a population of extended galaxies but with relatively low luminosities. The origin of these objects remains unclear, largely due to the observational challenges of the low surface brightness Universe. We present here a detailed stellar population analysis of a relatively isolated UDG, DGSAT I, based on spectroscopic data from the Keck Cosmic Web Imager integral field unit. The star formation history of DGSAT I seems to be extended, with a mean luminosity-weighted age of ∼3 Gyr, in agreement with previous photometric studies. However, we find a very high [Mg/Fe] abundance ratio, which is extreme even ...


Veritas And Fermi-Lat Observations Of Tev Gamma-Ray Sources Discovered By Hawc In The 2hwc Catalog, John Hewitt 2019 University of North Florida

Veritas And Fermi-Lat Observations Of Tev Gamma-Ray Sources Discovered By Hawc In The 2hwc Catalog, John Hewitt

Showcase of Faculty Scholarly & Creative Activity

The High Altitude Water Cherenkov (HAWC) collaboration recently published their 2HWC catalog, listing 39 very high energy (VHE; >100 GeV) gamma-ray sources based on 507 days of observation. Among these, 19 sources are not associated with previously known teraelectronvolt (TeV) gamma-ray sources. We have studied 14 of these sources without known counterparts with VERITAS and Fermi-LAT. VERITAS detected weak gamma-ray emission in the 1 TeV–30 TeV band in the region of DA 495, a pulsar wind nebula coinciding with 2HWC J1953+294, confirming the discovery of the source by HAWC. We did not find any counterpart for the selected ...


Magic And Fermi-Lat Gamma-Ray Results On Unassociated Hawc Sources, John Hewitt 2019 University of North Florida

Magic And Fermi-Lat Gamma-Ray Results On Unassociated Hawc Sources, John Hewitt

Showcase of Faculty Scholarly & Creative Activity

The HAWC Collaboration released the 2HWC catalogue of TeV sources, in which 19 show no association with any known high-energy (HE; E>10 GeV) or very-high-energy (VHE; E>300 GeV) sources. This catalogue motivated follow-up studies by both the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) and Fermi-LAT (Large Area Telescope) observatories with the aim of investigating gamma-ray emission over a broad energy band. In this paper, we report the results from the first joint work between High Altitude Water Cherenkov (HAWC), MAGIC, and Fermi-LAT on three unassociated HAWC sources: 2HWC J2006+341, 2HWC J1907+084*, and 2HWC J1852+013*. Although ...


A Second Galaxy Missing Dark Matter In The Ngc 1052, Pieter van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron Romanowsky 2019 Yale University

A Second Galaxy Missing Dark Matter In The Ngc 1052, Pieter Van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron Romanowsky

Faculty Publications

The ultra-diffuse galaxy NGC1052-DF2 has a very low velocity dispersion, indicating that it has little or no dark matter. Here we report the discovery of a second galaxy in this class, residing in the same group. NGC1052-DF4 closely resembles NGC1052-DF2 in terms of its size, surface brightness, and morphology; has a similar distance of Dsbf =  19.9 2.8 Mpc; and also has a population of luminous globular clusters extending out to 7 kpc from the center of the galaxy. Accurate radial velocities of the diffuse galaxy light and seven of the globular clusters were obtained with the Low Resolution ...


A Second Galaxy Missing Dark Matter In The Ngc 1052 Group, Pieter van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron Romanowsky 2019 Yale University

A Second Galaxy Missing Dark Matter In The Ngc 1052 Group, Pieter Van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron Romanowsky

Faculty Publications

The ultra-diffuse galaxy NGC1052-DF2 has a very low velocity dispersion, indicating that it has little or no dark matter. Here we report the discovery of a second galaxy in this class, residing in the same group. NGC1052-DF4closely resembles NGC1052-DF2 in terms of its size, surface brightness, and morphology; has a similar distance of Dsbf = 19.9 +/- 2.8 Mpc; and also has a population of luminous globular clusters extending out to >7 kpc from the center of the galaxy. Accurate radial velocities of the diffuse galaxy light and seven of the globular clusters were obtained with the Low Resolution Imaging ...


A Second Galaxy Missing Dark Matter In The Ngc 1052, Pieter van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron J. Romanowsky 2019 Yale University

A Second Galaxy Missing Dark Matter In The Ngc 1052, Pieter Van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron J. Romanowsky

Aaron J. Romanowsky

The ultra-diffuse galaxy NGC1052-DF2 has a very low velocity dispersion, indicating that it has little or no dark matter. Here we report the discovery of a second galaxy in this class, residing in the same group. NGC1052-DF4 closely resembles NGC1052-DF2 in terms of its size, surface brightness, and morphology; has a similar distance of Dsbf =  19.9 2.8 Mpc; and also has a population of luminous globular clusters extending out to 7 kpc from the center of the galaxy. Accurate radial velocities of the diffuse galaxy light and seven of the globular clusters were obtained with the Low Resolution ...


Long-Period Giant Companions To Three Compact, Multiplanet Systems, Sean M. Mills, Andrew W. Howard, Lauren M. Weiss, Jason H. Steffen, Howard Isaacson, Benjamin Fulton, Erik A. Petigura, Molly R. Kosiarek, Lea A. Hirsch, John H. Boisvert 2019 California Institute of Technology

Long-Period Giant Companions To Three Compact, Multiplanet Systems, Sean M. Mills, Andrew W. Howard, Lauren M. Weiss, Jason H. Steffen, Howard Isaacson, Benjamin Fulton, Erik A. Petigura, Molly R. Kosiarek, Lea A. Hirsch, John H. Boisvert

Physics & Astronomy Faculty Publications

Understanding the relationship between long-period giant planets and multiple smaller short-period planets is critical for formulating a complete picture of planet formation. This work characterizes three such systems. We present Kepler-65, a system with an eccentric (e = 0.28 ± 0.07) giant planet companion discovered via radial velocities (RVs) exterior to a compact, multiply transiting system of sub-Neptune planets. We also use precision RVs to improve mass and radius constraints on two other systems with similar architectures, Kepler-25 and Kepler-68. In Kepler-68 we propose a second exterior giant planet candidate. Finally, we consider the implications of these systems for planet ...


Galactic Preservation And Beyond: A Framework For Protecting Cultural, Natural, And Scientific Heritage In Space, Matthew Rosendahl 2019 College of William & Mary Law School

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 2019 Georgia State University

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 +_ ...


Charged Compact Binary Coalescence Signal And Electromagnetic Counterpart Of Plunging Black Hole–Neutron Star Mergers, Bing Zhang 2019 University of Nevada, Las Vegas

Charged Compact Binary Coalescence Signal And Electromagnetic Counterpart Of Plunging Black Hole–Neutron Star Mergers, Bing Zhang

Physics & Astronomy Faculty Publications

If at least one of the members of a compact binary coalescence is charged, the inspiral of the two members would generate a Poynting flux with an increasing power, giving rise to a brief electromagnetic counterpart temporally associated with the chirp signal of the merger (with possibly a small temporal offset), which we term as the charged compact binary coalescence (cCBC) signal. We develop a general theory of cCBC for any mass and amount of charge for each member. Neutron stars (NSs), as spinning magnets, are guaranteed to be charged, so the cCBC signal should accompany all NS mergers. The ...


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

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: Connecting Through Listening & Scholarship

No abstract provided.


Table Of Contents, 2019 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


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

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]


Erratum: “The Sluggs Survey: A Catalog Of Globular Cluster Radial Velocities” (2017, Aj, 153, 114), Duncan Forbes, Adebusola Alabi, Jean Brodie, Aaron Romanowsky, Jay Strader, Caroline Foster, Christopher Usher, Lee Spitler, Sabine Bellstedt, Nicola Pastorello, Sreeja Kartha, Zach Jennings, Alexa Villaume, Asher Wasserman, Vincenzo Pota 2019 Swinburne University of Technology

Erratum: “The Sluggs Survey: A Catalog Of Globular Cluster Radial Velocities” (2017, Aj, 153, 114), Duncan Forbes, Adebusola Alabi, Jean Brodie, Aaron Romanowsky, Jay Strader, Caroline Foster, Christopher Usher, Lee Spitler, Sabine Bellstedt, Nicola Pastorello, Sreeja Kartha, Zach Jennings, Alexa Villaume, Asher Wasserman, Vincenzo Pota

Faculty Publications

We would like to point out to the reader that the catalog of globular cluster (GC) radial velocities (listed in Table 5) still contains some multiple entries. In such cases GCs were observed more than once and are recorded in Table 5 with a unique GC ID, along with their coordinates and radial velocity measurement. If the reader wishes to exclude, or average, multiple measurements then GCs within one spatial pixel (i.e., 0.119 arcsec) in R.A. and decl. can be identified. This would include two dozen GCs in the galaxies NGC 720, 1407, 2768, 3608, 4365, 4459 ...


Book Review: Exoplanets : Hidden Worlds And The Quest For Extraterrestrial Life, T. D. Oswalt 2019 Embry-Riddle Aeronautical University

Book Review: Exoplanets : Hidden Worlds And The Quest For Extraterrestrial Life, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Exoplanets : Hidden Worlds and the Quest for Extraterrestrial Life. Harvard, 2018. 254p bibl index, 9780674976900 $24.95, 9780674988897


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