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Compiled Thesis
SPACE ROCKS: a series of papers on METEORITES AND ASTEROIDS by Nina Louise Hooper A thesis submitted to the Department of Astronomy in partial fulfillment of the requirement for the Bachelor’s Degree with Honors Harvard College 8 April 2016 Of all investments into the future, the conquest of space demands the greatest efforts and the longest-term commitment, but it also offers the greatest reward: none less than a universe. — Daniel Christlein !ii Acknowledgements I finished this senior thesis aided by the profound effort and commitment of my thesis advisor, Martin Elvis. I am extremely grateful for him countless hours of discussions and detailed feedback on all stages of this research. I am also grateful for the remarkable people at Harvard-Smithsonian Center for Astrophysics of whom I asked many questions and who took the time to help me. Special thanks go to Warren Brown for his guidance with spectral reduction processes in IRAF, Francesca DeMeo for her assistance in the spectral classification of our Near Earth Asteroids and Samurdha Jayasinghe and for helping me write my data analysis script in python. I thank Dan Holmqvist for being an incredibly helpful and supportive presence throughout this project. I thank David Charbonneau, Alicia Soderberg and the members of my senior thesis class of astrophysics concentrators for their support, guidance and feedback throughout the past year. This research was funded in part by the Harvard Undergraduate Science Research Program. !iii Abstract The subject of this work is the compositions of asteroids and meteorites. Studies of the composition of small Solar System bodies are fundamental to theories of planet formation. -
FINAL REPORT NASA Grant NAGW-3044 Observations of Spacecraft Targets, Unusual Asteroids, and Targets of Opportunity David J
FINAL REPORT NASA Grant NAGW-3044 Observations of Spacecraft Targets, Unusual Asteroids, and Targets of Opportunity David J. Tholen, P.I. Dates 1992 April 1 to 1998 March 31 Location University of Hawaii Institute for Astronomy 2680 Woodlawn Drive Honolulu, HI 96822 Goals Obtain physical and astrometric observations of (a) spacecraft targets to support mission operations, (b) known asteroids with unusual orbits to help determine their origin, and (c) newly discovered minor planets (including both asteroids and comets) that represent a particular opportunity to add significant new knowledge of the Solar System. Observations and Data Analysis Priority was given to the acquisition and analysis of observations of spacecraft targets, including (951) Gaspra and (243) Ida, both flyby targets of the Galileo spacecraft, (1620) Geographos, a flyby target for the Clementine spacecraft, (253) Mathilde and (433) Eros, both targets of the NEAR spacecraft, (4660) Nereus, a target for both the MUSES-C and NEAP missions, P/Wild 2, a target for the Stardust mission, and P/Wirtanen, a target for the Rosetta mission. Although the observations of Gaspra were obtained under an earlier grant, the analysis and publication of those data continued under this grant. Observations of Ida included both lightcurve data that were combined with similar data obtained by others to develop a pre-encounter shape and spin axis orientation model, thermal infrared data to determined a radiometric size and geometric albedo for the asteroid, and astrometry to assist with the spacecraft navigation effort, which had been compromised by the high-gain antenna problem. Although Clementine did not succeed in getting to Geographos, a wealth of new ground-based lightcurve observations, including some obtained with support from this grant, were used to develop a shape and spin model for the asteroid, comparable to the one done for Ida. -
Mitigation of Hazardous Comets and Asteroids
MITIGATION OF HAZARDOUS COMETS AND ASTEROIDS It is known that large asteroids and comets can collide with the Earth with severe consequences. Although the chances of a collision in a person’s lifetime are small, collisions are a random process and could occur at any time. This book collects the latest thoughts and ideas of scientists concerned with mitigating the threat of hazardous asteroids and comets. It reviews current knowledge of the population of potential colliders, including their numbers, locations, orbits, and how warning times might be improved. The structural properties and composition of their interi- ors and surfaces are reviewed, and their orbital response to the application of pulses of energy is discussed. Difficulties of operating in space near, or on the surface of, very low mass objects are examined. The book concludes with a discussion of the problems faced in communicating the nature of the impact hazard to the public. Michael Belton is Emeritus Astronomer at the National Optical Astronomy Observatory, Tucson, Arizona, and President of Belton Space Exploration Initia- tives, LLC. Thomas Morgan is a Discipline Scientist in the Office of Space Science at the National Aeronautics and Space Administration, Washington, District of Columbia. Nalin Samarasinha is an Assistant Scientist at the National Optical Astron- omy Observatory, Tucson, Arizona. Donald Yeomans manages NASA’s Near-Earth Object Program Office and JPL’s Solar System Dynamics group at the Jet Propulsion Laboratory of the Cali- fornia Institute of Technology, Pasadena, California. MITIGATION OF HAZARDOUS COMETS AND ASTEROIDS edited by MICHAEL J. S. BELTON Belton Space Exploration Initiatives, LLC THOMAS H. -
Spectral Properties of the Largest Asteroids Associated with Taurid Complex
Astronomy & Astrophysics manuscript no. AST3TC c ESO 2021 June 28, 2021 Spectral properties of the largest asteroids associated with Taurid Complex M. Popescu1, 2, M. Birlan1, D. A. Nedelcu2, J. Vaubaillon1, and C. P. Cristescu3 1 Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE) CNRS-UMR8028, Observatoire de Paris, 77 avenue Denfert-Rochereau, 75014 Paris Cedex, France 2 Astronomical Institute of the Romanian Academy, 5 Cu¸titul de Argint, 040557 Bucharest, Romania 3 Department of Physics, University Politehnica of Bucharest, Romania June 28, 2021 ABSTRACT Context. The Taurid Complex is a massive stream of material in the inner part of the Solar System. It contains objects spanning the range of 10−6–103m, considered by some authors to have a common cometary origin. The asteroids belonging to Taurid Complex are on Apollo type orbit, with most of them being flagged as potentially hazardous asteroids. In this context, understanding the nature and the origin of this asteroidal population is not only of scientific interest but also of practical importance. Aims. We aim to investigate the surface mineralogy of the asteroids associated with Taurid Complex using visible and near-infrared spectral data. Compositional linking between these asteroids and meteorites can be derived based on the obtained spectra. Methods. We obtained spectra of six of the largest asteroids (2201, 4183, 4486, 5143, 6063, and 269690) associated with Taurid complex. The observations were made with the IRTF telescope equipped with the spectro-imager SpeX. Their taxonomic classifi- cation is made using Bus-DeMeo taxonomy. The asteroid spectra are compared with the meteorite spectra from the Relab database. -
Solar Radiation and Near-Earth Asteroids: Thermophysical Modeling and New Measurements of the Yarkovsky Effect
University of California Los Angeles Solar Radiation and Near-Earth Asteroids: Thermophysical Modeling and New Measurements of the Yarkovsky Effect A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Geophysics and Space Physics by Carolyn Rosemary Nugent 2013 c Copyright by Carolyn Rosemary Nugent 2013 Abstract of the Dissertation Solar Radiation and Near-Earth Asteroids: Thermophysical Modeling and New Measurements of the Yarkovsky Effect by Carolyn Rosemary Nugent Doctor of Philosophy in Geophysics and Space Physics University of California, Los Angeles, 2013 Professor Jean-Luc Margot, Chair This dissertation examines the influence of solar radiation on near-Earth asteroids (NEAs); it investigates thermal properties and examines changes to orbits caused by the process of anisotropic re-radiation of sunlight called the Yarkovsky effect. For the first portion of this dissertation, we used geometric albedos (pV ) and diameters derived from the Wide-Field Infrared Survey Explorer (WISE), as well as geometric albedos and diameters from the literature, to produce more accurate diurnal Yarkovsky drift predic- tions for 540 NEAs out of the current sample of ∼ 8800 known objects. These predictions are intended to assist observers, and should enable future Yarkovsky detections. The second portion of this dissertation introduces a new method for detecting the Yarkovsky drift. We identified and quantified semi-major axis drifts in NEAs by performing orbital fits to optical and radar astrometry of all numbered NEAs. We discuss on a subset of 54 NEAs that exhibit some of the most reliable and strongest drift rates. Our selection criteria include a Yarkovsky sensitivity metric that quantifies the detectability of semi-major axis drift in any given data set, a signal-to-noise metric, and orbital coverage requirements. -
Spectral Properties of the Largest Asteroids Associated with Taurid Complex
A&A 572, A106 (2014) Astronomy DOI: 10.1051/0004-6361/201424064 & c ESO 2014 Astrophysics Spectral properties of the largest asteroids associated with Taurid Complex M. Popescu1,2, M. Birlan1, D. A. Nedelcu2, J. Vaubaillon1, and C. P. Cristescu3 1 Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE) CNRS-UMR 8028, Observatoire de Paris, 77 avenue Denfert-Rochereau, 75014 Paris Cedex, France e-mail: [email protected] 2 Astronomical Institute of the Romanian Academy, 5 Cu¸titul de Argint, 040557 Bucharest, Romania 3 Department of Physics, University Politehnica of Bucharest, Romania Received 25 April 2014 / Accepted 1 September 2014 ABSTRACT Context. The Taurid Complex is a massive stream of material in the inner part of the Solar System. It contains objects spanning the range of 10−6–103 m, considered by some authors to have a common cometary origin. The asteroids belonging to Taurid Complex are on Apollo type orbit, with most of them being flagged as potentially hazardous asteroids. In this context, understanding the nature and the origin of this asteroidal population is not only of scientific interest but also of practical importance. Aims. We aim to investigate the surface mineralogy of the asteroids associated with Taurid Complex using visible and near-infrared spectral data. Compositional linking between these asteroids and meteorites can be derived based on the obtained spectra. Methods. We obtained spectra of six of the largest asteroids (2201, 4183, 4486, 5143, 6063, and 269690) associated with Taurid complex. The observations were made with the IRTF telescope equipped with the spectro-imager SpeX. Their taxonomic classifi- cation is made using Bus-DeMeo taxonomy. -
Thedatabook.Pdf
THE DATA BOOK OF ASTRONOMY Also available from Institute of Physics Publishing The Wandering Astronomer Patrick Moore The Photographic Atlas of the Stars H. J. P. Arnold, Paul Doherty and Patrick Moore THE DATA BOOK OF ASTRONOMY P ATRICK M OORE I NSTITUTE O F P HYSICS P UBLISHING B RISTOL A ND P HILADELPHIA c IOP Publishing Ltd 2000 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the publisher. Multiple copying is permitted in accordance with the terms of licences issued by the Copyright Licensing Agency under the terms of its agreement with the Committee of Vice-Chancellors and Principals. British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. ISBN 0 7503 0620 3 Library of Congress Cataloging-in-Publication Data are available Publisher: Nicki Dennis Production Editor: Simon Laurenson Production Control: Sarah Plenty Cover Design: Kevin Lowry Marketing Executive: Colin Fenton Published by Institute of Physics Publishing, wholly owned by The Institute of Physics, London Institute of Physics Publishing, Dirac House, Temple Back, Bristol BS1 6BE, UK US Office: Institute of Physics Publishing, The Public Ledger Building, Suite 1035, 150 South Independence Mall West, Philadelphia, PA 19106, USA Printed in the UK by Bookcraft, Midsomer Norton, Somerset CONTENTS FOREWORD vii 1 THE SOLAR SYSTEM 1 -
Near-Earth Asteroid Surface Roughness Depends on Compositional Class ∗ Lance A.M
ARTICLE IN PRESS YICAR:8714 JID:YICAR AID:8714 /FLA [m5G; v 1.65; Prn:8/10/2008; 15:52] P.1 (1-11) Icarus ••• (••••) •••–••• Contents lists available at ScienceDirect Icarus www.elsevier.com/locate/icarus Near-Earth asteroid surface roughness depends on compositional class ∗ Lance A.M. Benner a, ,StevenJ.Ostroa, Christopher Magri b, Michael C. Nolan c, Ellen S. Howell c, Jon D. Giorgini a, Raymond F. Jurgens a, Jean-Luc Margot d, Patrick A. Taylor d, Michael W. Busch e, Michael K. Shepard f a Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA b University of Maine at Farmington, 173 High Street, Preble Hall, Farmington, ME 04938, USA c Arecibo Observatory, HC3 Box 53995, Arecibo, PR 00612, USA d Department of Astronomy, Cornell University, Ithaca, NY 14853, USA e Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA f Department of Geography and Geosciences, Bloomsburg University, Bloomsburg, PA 17815, USA article info abstract Article history: Radar observations of 214 near-Earth asteroids (NEAs) reveal a very strong correlation of circular Received 21 February 2008 polarization ratio with visible–infrared taxonomic class, establishing distinct differences in the centimeter- Revised 18 June 2008 to-several-decimeter structural complexity of objects in different spectral classes. The correlation may be due to the intrinsic mechanical properties of different mineralogical assemblages but also may reflect very different formation ages and collisional histories. The highest ratios are measured for groups Keywords: Near-Earth objects associated with achondritic igneous rocky meteorites: the E class, whose parent body may be 3103 Asteroids Eger, and the V class, derived from the mainbelt asteroid (and Dawn mission target) 4 Vesta. -
Compositional Mapping of Minor Planets Population Using Near
CompositionalCompositional mappingmapping ofof minorminor planetsplanets populationpopulation usingusing near-infrarednear-infrared datadata Marcel Popescu Observatoire de Paris - IMCCE 11, 2016 Few words about Astronomical Institute of the Romanian Academy ● Astronomical Institute was founded on 1908 by Nicolae Coculescu and it currently belongs to the Romanian Academy; ● The main building is located in Bucharest (in the Carol Park areea). The oldest instruments are the Meridian Circle (D=0.15 m) - 1916, and the Prin-Merz double refractor (F=6 m, D=0.38 m) used to obtain 13 000 photographic plates between 1931 - 2000. ● There are 30 employees (20 researchers and 10 auxiliary staff). The planetary sciences group from AIRA includes: Alin Nedelcu, Tavi Badescu, Marcel Popescu, Petre Paraschiv, Bogdan Dumitru, Radu Gherase, and Adrian Sonka. Main building of Astronomical Institute - Bucharest The Meridian Circle Abstract ● About 700 000 minor planets (small bodies of the Solar System orbiting the Sun) are known today. They occupy a variety of orbits ranging from near-Earth to Kuiper Belt. ● Physical characterization of small bodies through the use of reflectance spectroscopy provides insight into the diversity of their chemical compositions. ● Visible colors and albedo of about 100 000 obtained by SDSS and WISE allows to perform a large scale characterization (DeMeo et al. - Asteroids IV). ● I will discuss several techniques used to obtain the surface composition of minor planets and I will introduce a new large set of near-infrared colors for 39 947 small bodies of the Solar System – MOVIS (Popescu et al., 2016). This set resulted from VISTA-VHS survey observations, provides new means to reveal detailed compositional groups in the minor planets population. -
Orbit-Dependent Spectral Trends for the Near-Earth Asteroid Population
Orbit-Dependent Spectral Trends for the Near-Earth Asteroid Population Item Type text; Electronic Dissertation Authors Fevig, Ronald Adrey Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 02/10/2021 02:26:09 Link to Item http://hdl.handle.net/10150/195785 ORBIT-DEPENDENT SPECTRAL TRENDS FOR THE NEAR-EARTH ASTEROID POPULATION by Ronald Adrey Fevig _____________________ A Dissertation Submitted to the Faculty of the DEPARTMENT OF PLANETARY SCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2006 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Ronald Fevig entitled "Orbit-Dependent Spectral Trends for the Near-Earth Asteroid Population" and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy _______________________________________________________________________ Date: November 16, 2006 Uwe Fink _______________________________________________________________________ Date: November 16, 2006 Dante Lauretta _______________________________________________________________________ Date: November 16, 2006 -
Asteroid Radar Astronomy 151
Ostro et al.: Asteroid Radar Astronomy 151 Asteroid Radar Astronomy Steven J. Ostro Jet Propulsion Laboratory, California Institute of Technology R. Scott Hudson Washington State University Lance A. M. Benner and Jon D. Giorgini Jet Propulsion Laboratory, California Institute of Technology Christopher Magri University of Maine at Farmington Jean-Luc Margot California Institute of Technology Michael C. Nolan Arecibo Observatory Radar is a uniquely powerful source of information about the physical properties and orbits of asteroids. Measurements of the distribution of echo power in time delay (range) and Dop- pler frequency (radial velocity) produce two-dimensional images that can provide spatial reso- lution as fine as a decameter if the echoes are strong enough. With adequate orientational coverage, such images can be used to construct detailed three-dimensional models, define the rotation state precisely, and constrain the object’s internal density distribution. As of May 2002, radar signatures have been measured for 75 main-belt asteroids (MBAs) and 105 near-Earth asteroids (NEAs). We summarize specific results for radar-detected asteroids, which span 4 or- ders of magnitude in diameter and rotation period. Radar has revealed both stony and metallic objects, principal-axis and complex rotators, smooth and extremely rough surfaces, objects that must be monolithic and objects that probably are not, spheroids and highly elongated shapes, contact-binary shapes, and binary systems. Radar also has expanded accurate orbit-prediction intervals for NEAs by as much as several centuries. 1. INTRODUCTION summarize the major conclusions drawn from the explo- sive increase in data, and discuss current problems and chal- One of the goals of this book is to outline developments lenges to be faced during the coming decade. -
Compositional Mapping of Minor Planets Population Using Near-Infrared Data
CompositionalCompositional mappingmapping ofof minorminor planetsplanets populationpopulation usingusing near-infrarednear-infrared datadata Marcel Popescu 16 – Nov - 2017 Few words about Astronomical Institute of the Romanian Academy ● Astronomical Institute was founded on 1908 and it currently belongs to the Romanian Academy. ● The main building is located in Bucharest (in the Carol Park area). ● The planetary sciences group from AIRA includes: Alin Nedelcu, Ioana Boaca, Bogdan Dumitru, Radu Gherase, Adrian Sonka, Petre Paraschiv, Jad Mansour and Marcel Popescu. Main building of Astronomical Institute - Bucharest Why asteroids? ● About 750 000 minor planets (small bodies of the Solar System orbiting the Sun) are known today. They occupy a variety of orbits ranging from near-Earth to Kuiper Belt. ~700 000 Main Belt Asteroids (MBAs); ~17 000 Near Earth Asteroids (NEAs) → 1,850 potentially hazardous asteroids ( PHA) Why asteroids? Scientific point ± Key questions What were the processes occurring in the early Solar System? What are the physical properties of the building blocks of terrestrial planets? Do asteroids contain pre-solar material yet unknown in meteoritic samples? How asteroids can shed light on the origin of molecules necessary for life? Source: M.A. Barucci 2011 Space exploration of asteroids (Dawn, New- Horizons, OSIRIS-REx, Hayabusa2) Groundbased studies ± critical for space mission requirements; Practical point Space situational awareness ± impact to the Earth; Exploiting raw materials from asteroids. Hayabusa over Itokawa surface. Credit: JAXA Finding the physical properties of asteroids ● Photometry → lightcurve → rotation period → shape ● Spectro-photometry → surface composition ● Spectroscopy → surface composition ● Radar → shape, albedo, rotation period ● Polarimetry → surface properties (texture) Note: Telescope observations are limited by the atmosphere absorption Source: Carry, Ph.D.