Weighing Uranus' Moon Cressida with the $\Eta $ Ring
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7 Planetary Rings Matthew S
7 Planetary Rings Matthew S. Tiscareno Center for Radiophysics and Space Research, Cornell University, Ithaca, NY, USA 1Introduction..................................................... 311 1.1 Orbital Elements ..................................................... 312 1.2 Roche Limits, Roche Lobes, and Roche Critical Densities .................... 313 1.3 Optical Depth ....................................................... 316 2 Rings by Planetary System .......................................... 317 2.1 The Rings of Jupiter ................................................... 317 2.2 The Rings of Saturn ................................................... 319 2.3 The Rings of Uranus .................................................. 320 2.4 The Rings of Neptune ................................................. 323 2.5 Unconfirmed Ring Systems ............................................. 324 2.5.1 Mars ............................................................... 324 2.5.2 Pluto ............................................................... 325 2.5.3 Rhea and Other Moons ................................................ 325 2.5.4 Exoplanets ........................................................... 327 3RingsbyType.................................................... 328 3.1 Dense Broad Disks ................................................... 328 3.1.1 Spiral Waves ......................................................... 329 3.1.2 Gap Edges and Moonlet Wakes .......................................... 333 3.1.3 Radial Structure ..................................................... -
Planetary Ring Systems Edited by Matthew S
Cambridge University Press 978-1-107-11382-4 — Planetary Ring Systems Edited by Matthew S. Tiscareno , Carl D. Murray Frontmatter More Information Planetary Ring Systems Properties, Structure, and Evolution Planetary rings are among the most intriguing structures of our solar system and have fas- cinated generations of astronomers. Collating emerging knowledge in the field, this volume reviews our current understanding of ring systems with reference to the rings of Saturn, Uranus, Neptune, and more. Written by leading experts, the history of ring research and the basics of ring-particle orbits is followed by a review of the known planetary ring sys- tems. All aspects of ring system science are described in detail, including specific dynamical processes, types of structures, thermal properties, their origins, and investigations using com- puter simulations and laboratory experiments. The concluding chapters discuss the prospects of future missions to planetary rings, the ways in which ring science informs and is informed by the study of other astrophysical disks, and a perspective on the field’s future. Researchers of all levels benefit from this thorough and engaging presentation. MATTHEW S. TISCARENO is a Senior Research Scientist at the SETI Institute, California. He is a Participating Scientist and an Imaging Team Associate with the Cassini- Huygens mission. His research output includes solar system dynamics and space-based observations of the outer solar system. CARL D. MURRAYis Professor of Mathematics and Astronomy at Queen Mary Univer- sity of London. He has contributed to numerous ring and moon discoveries as an original member of the Imaging Team with the Cassini-Huygens mission and he is co-author of the textbook Solar System Dynamics (1999). -
The Rings and Inner Moons of Uranus and Neptune: Recent Advances and Open Questions
Workshop on the Study of the Ice Giant Planets (2014) 2031.pdf THE RINGS AND INNER MOONS OF URANUS AND NEPTUNE: RECENT ADVANCES AND OPEN QUESTIONS. Mark R. Showalter1, 1SETI Institute (189 Bernardo Avenue, Mountain View, CA 94043, mshowal- [email protected]! ). The legacy of the Voyager mission still dominates patterns or “modes” seem to require ongoing perturba- our knowledge of the Uranus and Neptune ring-moon tions. It has long been hypothesized that numerous systems. That legacy includes the first clear images of small, unseen ring-moons are responsible, just as the nine narrow, dense Uranian rings and of the ring- Ophelia and Cordelia “shepherd” ring ε. However, arcs of Neptune. Voyager’s cameras also first revealed none of the missing moons were seen by Voyager, sug- eleven small, inner moons at Uranus and six at Nep- gesting that they must be quite small. Furthermore, the tune. The interplay between these rings and moons absence of moons in most of the gaps of Saturn’s rings, continues to raise fundamental dynamical questions; after a decade-long search by Cassini’s cameras, sug- each moon and each ring contributes a piece of the gests that confinement mechanisms other than shep- story of how these systems formed and evolved. herding might be viable. However, the details of these Nevertheless, Earth-based observations have pro- processes are unknown. vided and continue to provide invaluable new insights The outermost µ ring of Uranus shares its orbit into the behavior of these systems. Our most detailed with the tiny moon Mab. Keck and Hubble images knowledge of the rings’ geometry has come from spanning the visual and near-infrared reveal that this Earth-based stellar occultations; one fortuitous stellar ring is distinctly blue, unlike any other ring in the solar alignment revealed the moon Larissa well before Voy- system except one—Saturn’s E ring. -
Abstracts of the 50Th DDA Meeting (Boulder, CO)
Abstracts of the 50th DDA Meeting (Boulder, CO) American Astronomical Society June, 2019 100 — Dynamics on Asteroids break-up event around a Lagrange point. 100.01 — Simulations of a Synthetic Eurybates 100.02 — High-Fidelity Testing of Binary Asteroid Collisional Family Formation with Applications to 1999 KW4 Timothy Holt1; David Nesvorny2; Jonathan Horner1; Alex B. Davis1; Daniel Scheeres1 Rachel King1; Brad Carter1; Leigh Brookshaw1 1 Aerospace Engineering Sciences, University of Colorado Boulder 1 Centre for Astrophysics, University of Southern Queensland (Boulder, Colorado, United States) (Longmont, Colorado, United States) 2 Southwest Research Institute (Boulder, Connecticut, United The commonly accepted formation process for asym- States) metric binary asteroids is the spin up and eventual fission of rubble pile asteroids as proposed by Walsh, Of the six recognized collisional families in the Jo- Richardson and Michel (Walsh et al., Nature 2008) vian Trojan swarms, the Eurybates family is the and Scheeres (Scheeres, Icarus 2007). In this theory largest, with over 200 recognized members. Located a rubble pile asteroid is spun up by YORP until it around the Jovian L4 Lagrange point, librations of reaches a critical spin rate and experiences a mass the members make this family an interesting study shedding event forming a close, low-eccentricity in orbital dynamics. The Jovian Trojans are thought satellite. Further work by Jacobson and Scheeres to have been captured during an early period of in- used a planar, two-ellipsoid model to analyze the stability in the Solar system. The parent body of the evolutionary pathways of such a formation event family, 3548 Eurybates is one of the targets for the from the moment the bodies initially fission (Jacob- LUCY spacecraft, and our work will provide a dy- son and Scheeres, Icarus 2011). -
Weighing Uranus' Moon Cressida with the Η Ring
The Astronomical Journal, 154:153 (8pp), 2017 October https://doi.org/10.3847/1538-3881/aa880e © 2017. The American Astronomical Society. All rights reserved. Weighing Uranus’ Moon Cressida with the η Ring Robert O. Chancia1 , Matthew M. Hedman1 , and Richard G. French2 1 Department of Physics, University of Idaho, Moscow, ID 83844-0903, USA; [email protected] 2 Astronomy Department, Wellesley College, Wellesley, MA 02481, USA Received 2017 June 19; revised 2017 August 9; accepted 2017 August 21; published 2017 September 20 Abstract The η ring is one of the narrow rings of Uranus, consisting of a dense core that is 1–2 km wide and a diffuse outer sheet spanning about 40 km. Its dense core lies just exterior to the 3:2 Inner Lindblad Resonance of the small moon Cressida. We fit the η ring radius residuals and longitudes from a complete set of both ground-based and Voyager stellar and radio occultations of the Uranian rings spanning 1977–2002. We find variations in the radial position of the η ring that are likely generated by this resonance, and take the form of a 3-lobed structure rotating at an angular rate equal to the mean motion of the moon Cressida. The amplitude of these radial oscillations is 0.667±0.113 km, which is consistent with the expected shape due to the perturbations from Cressida. The magnitude of these variations provides the first measurement of the mass and density of the moon Cressida (m =´()2.5 0.4 1017 kg and r =0.86 0.16 gcm−3) or, indeed, any of Uranus’ small inner moons. -
Arxiv:1509.00872V1 [Astro-Ph.EP] 2 Sep 2015 H Bevblt Fipcso in Xpaes H Oe Matc Impact Comet the Exoplanets
Detectability of Planetesimal Impacts on Giant Exoplanets Laura Flagga,b,∗, Alycia J. Weinbergerb, Keith Matthewsc aDepartment of Physics and Astronomy, Northern Arizona University, Flagstaff, AZ 86011-6010, USA bDepartment of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC 20015, USA cCaltech Optical Observatories, California Institute of Technology, MC 301-17, Pasadena, CA 91125, USA Abstract The detectability of planetesimal impacts on imaged exoplanets can be measured using Jupiter during the 1994 comet Shoemaker-Levy 9 events as a proxy. By integrating the whole planet flux with and without impact spots, the effect of the impacts at wavelengths from 2 - 4 µm is revealed. Jupiter’s reflected light spectrum in the near-infrared is dominated by its methane opacity including a deep band at 2.3 µm. After the impact, sunlight that would have normally been absorbed by the large amount of methane in Jupiter’s atmosphere was instead reflected by the cometary material from the impacts. As a result, at 2.3 µm, where the planet would normally have low reflectivity, it brightened substantially and stayed brighter for at least a month. Keywords: comets, debris disks, extra-solar planets, Jupiter 1. Introduction The frequencies with which giant planets and cold circumstellar debris disks encircle old (i.e. >1 Gyr) Sun-like stars are both ∼20% (Eiroa et al. 2013; Marshall et al. 2014). The debris disks are generated in the collisions and evaporation of planetesimals, analogous to the comets and asteroids of today’s Solar System. That most debris disks contain cold, ∼50 K, dust indicates that the reservoirs of parent bodies are at ∼100 AU from the parent stars, in a region analogous to our Edgeworth-Kuiper Belt. -
Exploring the Origins and Evolution of Ice Giant Planets
Exp Astron DOI 10.1007/s10686-011-9251-4 ORIGINAL ARTICLE Uranus Pathfinder: exploring the origins and evolution of Ice Giant planets Christopher S. Arridge Craig B. Agnor Nicolas André Kevin H. Baines · · · · Leigh N. Fletcher Daniel Gautier Mark D. Hofstadter Geraint H. Jones · · · · Laurent Lamy Yves Langevin Olivier Mousis Nadine Nettelmann · · · · Christopher T. Russell Tom Stallard Matthew S. Tiscareno · · · Gabriel Tobie Andrew Bacon Chris Chaloner Michael Guest · · · · Steve Kemble Lisa Peacocke Nicholas Achilleos Thomas P. Andert · · · · Don Banfield Stas Barabash Mathieu Barthelemy Cesar Bertucci · · · · Pontus Brandt Baptiste Cecconi Supriya Chakrabarti Andy F. Cheng · · · · Ulrich Christensen Apostolos Christou Andrew J. Coates · · · Glyn Collinson John F. Cooper Regis Courtin Michele K. Dougherty · · · · Robert W. Ebert Marta Entradas Andrew N. Fazakerley · · · Jonathan J. Fortney Marina Galand Jaques Gustin Matthew Hedman · · · · Ravit Helled Pierre Henri Sebastien Hess Richard Holme · · · · Özgur Karatekin Norbert Krupp Jared Leisner Javier Martin-Torres · · · · Adam Masters Henrik Melin Steve Miller Ingo Müller-Wodarg · · · · Benoît Noyelles Chris Paranicas Imke de Pater Martin Pätzold · · · · Renée Prangé Eric Quémerais Elias Roussos Abigail M. Rymer · · · · Agustin Sánchez-Lavega Joachim Saur Kunio M. Sayanagi Paul Schenk · · · · Gerald Schubert Nick Sergis Frank Sohl Edward C. Sittler Jr. · · · · Nick A. Teanby Silvia Tellmann Elizabeth P. Turtle Sandrine Vinatier · · · · Jan-Erik Wahlund Philippe Zarka · Received: 26 November 2010 / Accepted: 21 July 2011 ©SpringerScience+BusinessMediaB.V.2011 N. Achilleos Department of Physics and Astronomy, University College London, London, UK C. B. Agnor School of Physics and Astronomy, Queen Mary University of London, London, UK T. P. Andert Universität der Bundeswehr, Munich, Germany N. André Centre d’Etude Spatiale des Rayonnements / CNRS, Toulouse, France C. -
Uranus, Neptune, Pluto, and the Outer Solar System Linda T
Uranus, Neptune, Pluto, and the Outer Solar System Linda T. Elkins-Tanton Uranus, Neptune, Pluto, and the Outer Solar System Copyright © 2006 by Linda T.Elkins-Tanton All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechani- cal, including photocopying, recording, or by any information storage or retrieval systems, without permission in writing from the publisher. For information contact: Chelsea House An imprint of Infobase Publishing 132 West 31st Street New York NY 10001 Library of Congress Cataloging-in-Publication Data Elkins-Tanton, Linda T. Uranus, Neptune, Pluto, and the outer solar system / Linda T.Elkins-Tanton. p. cm. — (The Solar system) Includes bibliographical references and index. ISBN 0-8160-5197-6 (acid-free paper) 1. Uranus (Planet)—Popular works. 2. Neptune (Planet)—Popular works. 3. Pluto (Planet)—Popular works. 4. Solar system—Popular works. I.Title. QB681.E45 2006 523.47—dc22 2005014801 Chelsea House books are available at special discounts when purchased in bulk quantities for businesses, associations, institu- tions, or sales promotions. Please call our Special Sales Department in New York at (212) 967-8800 or (800) 322-8755. You can find Chelsea House on the World Wide Web at http://www.chelseahouse.com Text and cover design by Dorothy M. Preston Illustrations by Richard Garratt Printed in the United States of America VB Hermitage 10 9 8 7 6 5 4 3 2 1 This book is printed on acid-free paper. In memory of my brother Thomas Turner Elkins, who, when I was 10 years old, taught me about the Oort cloud, and together we named our pet mouse Oort. -
By: Maddie S. It Takes 84 Earth Years for It to Complete One Orbit
Uranus By: Maddie S. It takes 84 earth years for it to complete one orbit. It's radius is 400.1 miles. At its closest it orbits Uranus appeared to be 1.7 billion miles away. At its only a blue-green ball with farthest it orbits 1.9 billion miles a smooth surface. away. Uranus is too far away to see easily without a telescope. Uranus is the seventh planet Sometimes it is just bright from the sun. It orbits farther enough to see with the naked out, along Uranus's outer eye. ring. Uranus' high powered telescope at the Keck Observatory in Hawaii creates detailed images of Uranus. Each of Uranus' hemispheres receives 42 earth years of sunlight. Uranus' rings are a mix of large chunks of matter and fine particles of dust. One spacecraft has managed to visit Uranus but it took a little creativity to get it there. The rings orbiting Uranus are thinner than those orbiting other planets. Uranus has ten moons. Ariel is Uranus's brightest moon. The moons names are Juliet, Puck Cordelia, Ophelia, Bianca, Desdemona, Portia, Rosalind, Cressida, and Belinda. Umbriel is the darkest moon on Uranus. Uranus Uranus is so far away that for about 200 years scientists could not make out how quickly it turns on its axis. Most planets turn on their axis in such a way that they are almost upright as they move about the sun. It is the only planet with an axis tipped that way, so some think of it as a sideways planet. Like most planets, Uranus has its own natural satellites, or moons. -
Uranian and Saturnian Satellites in Comparison
Compara've Planetology between the Uranian and Saturnian Satellite Systems - Focus on Ariel Oberon Umbriel Titania Ariel Miranda Puck Julie Cas'llo-Rogez1 and Elizabeth Turtle2 1 – JPL, California Ins'tute of Technology 2 – APL, John HopKins University 1 Objecves Revisit observa'ons of Voyager in the Uranian system in the light of Cassini-Huygens’ results – Constrain planetary subnebula, satellites, and rings system origin – Evaluate satellites’ poten'al for endogenic and geological ac'vity Uranian Satellite System • Large popula'on • System architecture almost similar to Saturn’s – “small” < 200 Km embedded in rings – “medium-sized” > 200 Km diameter – No “large” satellite – Irregular satellites • Rela'vely high albedo • CO2 ice, possibly ammonia hydrates Daphnis in Keeler gap Accre'on in Rings? Charnoz et al. (2011) Charnoz et al., Icarus, in press) Porco et al. (2007) ) 3 Ariel Titania Oberon Density(kg/m Umbriel Configuraon determined by 'dal interac'on with Saturn Configura'on determined by 'dal interac'on within the rings Distance to Planet (Rp) Configuraon determined by Titania Oberon Ariel 'dal interac'on with Saturn Umbriel Configura'on determined by 'dal interac'on within the rings Distance to Planet (Rp) Evidence for Ac'vity? “Blue” ring found in both systems Product of Enceladus’ outgassing ac'vity Associated with Mab in Uranus’ system, but source if TBD Evidence for past episode of ac'vity in Uranus’ satellite? Saturn’s and Uranus’ rings systems – both planets are scaled to the same size (Hammel 2006) Ariel • Comparatively low -
02. Solar System (2001) 9/4/01 12:28 PM Page 2
01. Solar System Cover 9/4/01 12:18 PM Page 1 National Aeronautics and Educational Product Space Administration Educators Grades K–12 LS-2001-08-002-HQ Solar System Lithograph Set for Space Science This set contains the following lithographs: • Our Solar System • Moon • Saturn • Our Star—The Sun • Mars • Uranus • Mercury • Asteroids • Neptune • Venus • Jupiter • Pluto and Charon • Earth • Moons of Jupiter • Comets 01. Solar System Cover 9/4/01 12:18 PM Page 2 NASA’s Central Operation of Resources for Educators Regional Educator Resource Centers offer more educators access (CORE) was established for the national and international distribution of to NASA educational materials. NASA has formed partnerships with universities, NASA-produced educational materials in audiovisual format. Educators can museums, and other educational institutions to serve as regional ERCs in many obtain a catalog and an order form by one of the following methods: States. A complete list of regional ERCs is available through CORE, or electroni- cally via NASA Spacelink at http://spacelink.nasa.gov/ercn NASA CORE Lorain County Joint Vocational School NASA’s Education Home Page serves as a cyber-gateway to informa- 15181 Route 58 South tion regarding educational programs and services offered by NASA for the Oberlin, OH 44074-9799 American education community. This high-level directory of information provides Toll-free Ordering Line: 1-866-776-CORE specific details and points of contact for all of NASA’s educational efforts, Field Toll-free FAX Line: 1-866-775-1460 Center offices, and points of presence within each State. Visit this resource at the E-mail: [email protected] following address: http://education.nasa.gov Home Page: http://core.nasa.gov NASA Spacelink is one of NASA’s electronic resources specifically devel- Educator Resource Center Network (ERCN) oped for the educational community. -
Jupiter's Ring-Moon System
11 Jupiter’s Ring-Moon System Joseph A. Burns Cornell University Damon P. Simonelli Jet Propulsion Laboratory Mark R. Showalter Stanford University Douglas P. Hamilton University of Maryland Carolyn C. Porco Southwest Research Institute Larry W. Esposito University of Colorado Henry Throop Southwest Research Institute 11.1 INTRODUCTION skirts within the outer stretches of the main ring, while Metis is located 1000 km closer to Jupiter in a region where the ∼ Ever since Saturn’s rings were sighted in Galileo Galilei’s ring is depleted. Each of the vertically thick gossamer rings early sky searches, they have been emblematic of the ex- is associated with a moon having a somewhat inclined orbit; otic worlds beyond Earth. Now, following discoveries made the innermost gossamer ring extends towards Jupiter from during a seven-year span a quarter-century ago (Elliot and Amalthea, and exterior gossamer ring is connected similarly Kerr 1985), the other giant planets are also recognized to be with Thebe. circumscribed by rings. Small moons are always found in the vicinity of plane- Jupiter’s diaphanous ring system was unequivocally de- tary rings. Cuzzi et al. 1984 refer to them as “ring-moons,” tected in long-exposure images obtained by Voyager 1 (Owen while Burns 1986 calls them “collisional shards.” They may et al. 1979) after charged-particle absorptions measured by act as both sources and sinks for small ring particles (Burns Pioneer 11 five years earlier (Fillius et al. 1975, Acu˜na and et al. 1984, Burns et al. 2001). Ness 1976) had hinted at its presence. The Voyager flybys also discovered three small, irregularly shaped satellites— By definition, tenuous rings are very faint, implying Metis, Adrastea and Thebe in increasing distance from that particles are so widely separated that mutual collisions Jupiter—in the same region; they joined the similar, but play little role in the evolution of such systems.