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Infrared Observations of Cometary Solids INFRARED OBSERVATIONS OF COMETARY SOLIDS Item Type text; Dissertation-Reproduction (electronic) Authors CAMEJO, HUMBERTO CAMPINS 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 01:15:22 Link to Item http://hdl.handle.net/10150/185260 INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. 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When a map, drawing or chart, etc., is part of the material being photographed, a definite method of "sectioning" the material has been followed. It is customary to begin filming at the upper left hand comer of a large sheet and to continue from left to right in equal sections with small overlaps. If necessary, sectioning is continued again-beginning below the first row and continuing on until complete. 4. For illustrations that cannot be satisfactorily reproduced by xerographic means, photographic prints can be purchased at additional cost and inserted into your xerographic copy. These prints are available upon request from the Dissertations Customer Services Department. 5. Some pages in any document may have indistinct print. In all cases the best available copy has been filmed. University Micrc5films International 300 N. Zeeb Road Ann Arbor, MI481 06 8306449 Camejo, Humberto Camp ins INFRARED OBSERVATIONS OF COMETARY SOLIDS The University ofArizona PH.D. 1982 University Microfilms 1ntern ati 0 nal 300 N. Zeeb Road. Ann Arbor. MI 48106 PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark_-I_. 1. Glossy photographs or pages __ 2. Colored illustrations, paper or print __ 3. Photographs with dark background __ 4. Illustrations are poor copy __ 5. Pages with black marks, not original copy __ 6. Print shows through as there is text on both sides of page __ 7. Indistinct, broken or small print on several pages ,/" 8. Print exceeds margin requirements __ 9. Tightly bound copy with print lost in spine __ 10. Computer printout pages with indistinct print __ 11. Page(s) lacking when material received, and not available from school or author. 12. 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Other__________________________ _ University Microfilms International INFRARED OBSERVATIONS OF COMETARY SOLIDS by Humberto Campins Camejo A Dissertation Submitted to the Faculty of the DEPARTMENT OF PLANETARY SCIENCE In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 198 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Final Examination Committee, we certify that we have read the dissertation prepared by Humberto Campins Camejo entitled Infrared Observations of Cometary Solids ----------------------~------~~~~~-------------------- and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy Date ~LdII- -=6 Date -~-~--~::;....;;.....--~---,-~-~----"..;;....;......--- Date ~o iLL " y Date Final approval and acceptance of this dissertation is contingent upon the candidate's submission of the final copy of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. Diss;;ta~on Director Date STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requi rements for an advanced degree at The Uni versity of Ari zona and is deposited in the University Library to be made available to borrowers under the rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for perm iss i on for extended qu otat i on from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. ACKNOWLEDGMENTS There have been many people who, in different ways, have contributed to the completion of this work; some of them are: my parents, Cl ara Camejo de Campins and HLlmberto Campins Macias, who gave me all their support; George Rieke, my advisor, who patiently guided me through all the projects which led to the dissertation; Marcia Rieke, unofficially my co-advisor; John Gradie, Martha Hanner and Larry Lebofsky for collaboration in projects which were included in the disseration; Nick Gautier, Jim Higdon, Cliff Stoll, David Tholen, Martin Tomasko, John Wacker, Faith Vilas and Bruce Wilking for useful discussion; and Vicki Adams for her help with the typing, etc. Special thanks go to Laura E. Lucero for her invaluable support and inspiration. I am indebted to the Venezuelan Council for Scientific and Technological Research (Conicit) for financial support, and the University of Arizona and IRTF telescope allocating committees for the time received. iii TABLE OF CONTENTS Page LIST OF TABLES • • • • · . vi LIST OF ILLUSTRATIONS · . vii ABSTRACT •• . viii 1. INTRODUCTION . .. 1 Structure of the Nucleus and Physical Processes Around It • • • • • • • • • • • • • • • • • • • • • • •• 3 Structure and Composition •••••••••••••• 3 Sublimation of Ices ••••••••••••••••• 4 Transport of the Dust • • • • • • • • • • • • • • •• 7 2. OBSERVATIONAL TECHNIQUE . 12 The Photometric System •••••••••••••• · . 12 Detectors • • • • • • • • • • • • • • • • • • • • • · . 13 Modulation •••••••••••••••••••• · . 15 3. ANALYSIS •••• . • • . • • • . • • • . 17 Assumptions • • • • • • • • • • • • • • • • • • • • • • • 17 Albedos ••••••••••••••••••••••• 17 Coma Structure • • • • • • • • • • • • • • • • • • 19 Errors • • • • • • • • • • • • • • • • • • • • • • • • • 20 Theoretical Methods • • • • • • • • • • • • • • • • • • • 21 Scattering. • • • • • • • • • • • • • • • • • • • • • 21 Thermal Emission • • • • • • • • • • • • • • • • • • • 22 4. NONPERIODIC COMETS, •• • • • • • • • • • • • • • • • • • • 24 Nature of the Cometary Dust • • • • • • • • • • • • • • • 24 Comet West • • • • • • • • • • • • • • • • • • • • • • • 29 Comet Bowell •••••••••••••••••••••• 43 First Program •••••••••••••••••••• 44 Discussion • • • • • • • • • • • • • • • • • • • • • • 51 Second Program • • • • • • • • • • • • • • • • • • • • 61 iv v TABLE OF CONTENTS--Continued Page 5. PERIOD COMETS • • • • • • • • • • • • • • • • • • • • • • • 67 Observations •••••••••••••••••••••• 67 Discussion • • • • • • • • • • • • • • • • • • • • • • • 69 JHK Colors • • • • • • • • • • • • • • • • • • • • • • 69 Thermal Curve • • • • • • • • • • • • • • • • • • • • 71 Albedo • • • • • • • • • • • • • • • • • • • • • • • • 75 Comet Encke ••••••••••••••••• • • • • 76 Conclusions. • • • • • • • • • • • • • • • • • • • • • • 77 6. SUMMARY AND CONCLUSIONS . 78 Characteristics of Cometary Solids • • • • • • • • • • • 78 Structure of the Nucleus • • • • • • • • • • • • • • • • 79 Small Scale • • • • • • • • • • • • • • • • • • • • • 79 large Scale • • • • • • • • • • • • • • • • • • • • • 80 Relation Between Cometary and Interstellar Dust • • • • • 83 Origin of IIGassy" and IIDustyll Comets •••••••••• 86 REFERENCES . 89 LIST OF TABLES Table Page 1. The Photometric System. • • • • • • • • • • • • • • • •• 14 2. Photometry of Comet West • • • • • • • • • • • • • • • •• 30 3. 1.25 to 3.45 )lm Magnitudes. • • • • • • • • • • • • • • • 45 4. Comet Bri ghtness at K (2.2 )lorn) • • • • • • • • • • • • •• 50 5. Summary of the Infrared Observations ••••••• •• 68 6. JHK Colors •• . • • 70 7. Temperatures. • • • • • • • • • 0 • • • • • • • • 72 8. Albedos . • • • • • • • • • • • • • • • • • • • 74 • vi LIST OF ILLUSTRATIONS Figure ·Page 1. Flux ratio 1(4.8/ ~m)/I(3.5 ~m) vs. heliocentric distance for five comets •••••••.•. 26 2. Flux ratio 1(4.8 ~)/I(3.5 ~m) for size distribution of 28 s11 icate grains 3. Observations of Comet Kohoutek on December 19.7 1973. 31 4. Observations of Comet
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