Observational Constraints on Surface Characteristics of Comet Nuclei

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12 10
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KBOs
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Centaurs

876543210
Nuclei

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Dead Comets

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Reflectivity Gradient, S' [%/1000 Å]

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Surface Characteristics of Transneptunian Objects and Centaurs from Photometry and Spectroscopy

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KAREN J. MEECH February 7, 2019 Astronomer

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Investigation of Dust and Water Ice in Comet 9P/Tempel 1 from Spitzer Observations of the Deep Impact Event

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Photometric Study of Two Near-Earth Asteroids in the Sloan Digital Sky Survey Moving Objects Catalog

University of North Dakota UND Scholarly Commons Theses and Dissertations Theses, Dissertations, and Senior Projects January 2020 Photometric Study Of Two Near-Earth Asteroids In The Sloan Digital Sky Survey Moving Objects Catalog Christopher James Miko Follow this and additional works at: https://commons.und.edu/theses Recommended Citation Miko, Christopher James, "Photometric Study Of Two Near-Earth Asteroids In The Sloan Digital Sky Survey Moving Objects Catalog" (2020). Theses and Dissertations. 3287. https://commons.und.edu/theses/3287 This Thesis is brought to you for free and open access by the Theses, Dissertations, and Senior Projects at UND Scholarly Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of UND Scholarly Commons. For more information, please contact [email protected]. PHOTOMETRIC STUDY OF TWO NEAR-EARTH ASTEROIDS IN THE SLOAN DIGITAL SKY SURVEY MOVING OBJECTS CATALOG by Christopher James Miko Bachelor of Science, Valparaiso University, 2013 A Thesis Submitted to the Graduate Faculty of the University of North Dakota in partial fulfillment of the requirements for the degree of Master of Science Grand Forks, North Dakota August 2020 Copyright 2020 Christopher J. Miko ii Christopher J. Miko Name: Degree: Master of Science This document, submitted in partial fulfillment of the requirements for the degree from the University of North Dakota, has been read by the Faculty Advisory Committee under whom the work has been done and is hereby approved. ____________________________________ Dr. Ronald Fevig ____________________________________ Dr. Michael Gaffey ____________________________________ Dr. Wayne Barkhouse ____________________________________ Dr. Vishnu Reddy ____________________________________ ____________________________________ This document is being submitted by the appointed advisory committee as having met all the requirements of the School of Graduate Studies at the University of North Dakota and is hereby approved.
Limb Polarization of Uranus and Neptune I

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Comet Section Observing Guide

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Isotopic Ratios in Outbursting Comet C/2015 ER61

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The Spherical Bolometric Albedo of Planet Mercury

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Oort Cloud and Scattered Disc Formation During a Late Dynamical Instability in the Solar System ⇑ R

Icarus 225 (2013) 40–49 Contents lists available at SciVerse ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Oort cloud and Scattered Disc formation during a late dynamical instability in the Solar System ⇑ R. Brasser a, , A. Morbidelli b a Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan b Departement Lagrange, University of Nice – Sophia Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France article info abstract Article history: One of the outstanding problems of the dynamical evolution of the outer Solar System concerns the Received 11 January 2012 observed population ratio between the Oort cloud (OC) and the Scattered Disc (SD): observations suggest Revised 21 January 2013 that this ratio lies between 100 and 1000 but simulations that produce these two reservoirs simulta- Accepted 11 March 2013 neously consistently yield a value of the order of 10. Here we stress that the populations in the OC Available online 2 April 2013 and SD are inferred from the observed ﬂuxes of new long period comets (LPCs) and Jupiter-family comets (JFCs), brighter than some reference total magnitude. However, the population ratio estimated in the sim- Keywords: ulations of formation of the SD and OC refers to objects bigger than a given size. There are multiple indi- Origin, Solar System cations that LPCs are intrinsically brighter than JFCs, i.e. an LPC is smaller than a JFC with the same total Comets, Dynamics Planetary dynamics absolute magnitude. When taking this into account we revise the SD/JFC population ratio from our sim- ulations relative to Duncan and Levison (1997), and then deduce from the observations that the size-lim- þ54 ited population ratio between the OC and the SD is 44À34.
Characterization of the Physical Properties of the ROSETTA Target Comet 67P/Churyumov-Gerasimenko

Characterization of the physical properties of the ROSETTA target comet 67P/Churyumov-Gerasimenko Von der Fakultät für Elektrotechnik, Informationstechnik, Physik der Technischen Universität Carolo-Wilhelmina zu Braunschweig zur Erlangung des Grades einer Doktorin der Naturwissenschaften (Dr.rer.nat.) genehmigte Dissertation von Cecilia Tubiana aus Moncalieri/Italien Bibliografische Information Der Deutschen Bibliothek Die Deutsche Bibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.ddb.de abrufbar. 1. Referentin oder Referent: Prof. Dr. Jürgen Blum 2. Referentin oder Referent: Prof. Dr. Michael A’Hearn eingereicht am: 18 August 2008 mündliche Prüfung (Disputation) am: 30 Oktober 2008 ISBN 978-3-936586-89-3 Copernicus Publications 2008 http://publications.copernicus.org c Cecilia Tubiana Printed in Germany Contents Summary 7 1 Comets: introduction 11 1.1 Physical properties of cometary nuclei . 15 1.1.1 Size and shape of a cometary nucleus . 18 1.1.2 Rotational period of a cometary nucleus . 22 1.1.3 Albedo of cometary nuclei . 24 1.1.4 Bulk density of cometary nuclei . 25 1.1.5 Colors indices and spectra of the nucleus . 25 1.2 Dust trail and neck-line . 27 2 67P/Churyumov-Gerasimenko and the ESA’s ROSETTA mission 29 2.1 Discovery and orbital evolution . 29 2.2 Nucleus properties . 30 2.3 Annual light curve . 32 2.4 Gas and dust production . 32 2.5 Coma features, trail and neck-line . 35 2.6 ESA’s ROSETTA mission . 35 2.7 Motivations of the thesis . 39 3 Observing strategy and performance of the observations of 67P/C-G 41 3.1 Observations: strategy and preparation .
January 12-18, 2020

3# Ice & Stone 2020 Week 3: January 12-18, 2020 Presented by The Earthrise Institute This week in history JANUARY 12 13 14 15 16 17 18 JANUARY 12, 1910: A group of diamond miners in the Transvaal in South Africa spot a brilliant comet low in the predawn sky. This was the first sighting of what became known as the “Daylight Comet of 1910” (old style designations 1910a and 1910 I, new style designation C/1910 A1). It soon became one of the brightest comets of the entire 20th Century and will be featured as “Comet of the Week” in two weeks. JANUARY 12, 2005: NASA’S Deep Impact mission is launched from Cape Canaveral, Florida. Deep Impact would encounter Comet 9P/Tempel 1 in July of that year and – under the mission name “EPOXI” – would encounter Comet 103P/Hartley 2 in November 2010. Comet 9P/Tempel 1 is a future “Comet of the Week” and the Deep Impact mission – and its results – will be discussed in more detail at that time. JANUARY 12, 2007: Comet McNaught C/2006 P1, the brightest comet thus far of the 21st Century, passes through perihelion at a heliocentric distance of 0.171 AU. Comet McNaught is this week’s “Comet of the Week.” JANUARY 12 13 14 15 16 17 18 JANUARY 13, 1950: Jan Oort’s paper “The Structure of the Cloud of Comets Surrounding the Solar System, and a Hypothesis Concerning its Origin,” is published in the Bulletin of the Astronomical Institute of The Netherlands. In this paper Oort demonstrates that his calculations reveal the existence of a large population of comets enshrouding the solar system at heliocentric distances of tens of thousands of Astronomical Units.