University of North Dakota UND Scholarly Commons Theses and Dissertations Theses, Dissertations, and Senior Projects January 2014 Generating A Characterization Method Utilizing The iV sible (0.6-1.0 μm) Peak Feature To Aid In Identification Of Ordinary Chondrite Parent Bodies Cassandra Lynne Johnson Follow this and additional works at: https://commons.und.edu/theses Recommended Citation Johnson, Cassandra Lynne, "Generating A Characterization Method Utilizing The iV sible (0.6-1.0 μm) Peak Feature To Aid In Identification Of Ordinary Chondrite Parent Bodies" (2014). Theses and Dissertations. 1550. https://commons.und.edu/theses/1550 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]. GENERATING A CHARACTERIZATION METHOD UTILIZING THE VISIBLE (0.6-1.0 μm) PEAK FEATURE TO AID IN IDENTIFICATION OF ORDINARY CHONDRITE PARENT BODIES by Cassandra Lynne Johnson Associate of Arts, American InterContinental University, 2007 Bachelor of Science, Kansas State University, 2012 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 May 2014 This thesis, submitted by Cassandra Johnson in partial fulfillment of the requirements for the Degree of Master of Science 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 Mike Gaffey, Chairperson Dr David Whalen Dr Jaakko Putkonen This thesis is being submitted by the appointed advisory committee as having met all of the requirements of the Graduate School at the University of North Dakota and is hereby approved. Dr. Wayne Swisher, Dean of the Graduate School Date ii PERMISSION Title Generating a Characterization Method Utilizing The Visible (0.6-1.0 μm) Peak Feature to Aid in Identification of Ordinary Chondrite Parent Bodies Department Space Studies Degree Master of Science In presenting this thesis in partial fulfillment of the requirements for a graduate degree from the University of North Dakota, I agree that the library of this University shall make it freely available for inspection. I further agree that permission for extensive copying for scholarly purposes may be granted by the professor who supervised my thesis work or, in her absence, by the Chairperson of the department or the dean of the School of Graduate Studies. It is understood that any copying or publication or other use of this thesis or part thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of North Dakota in any scholarly use which may be made of any material in my thesis. Cassandra Lynne Johnson April 11, 2014 iii TABLE OF CONTENTS LIST OF FIGURES iv ACKNOWLEDGMENTS v ABSTRACT vi CHAPTER I. INTRODUCTION 1-19 Experimental Hypothesis 1 Meteorites 2 Meteorite Survey Databases 5 Meteorite Parent Bodies 6 Asteroids 7 Mineralogy & Crystal Field Theory 12 Spectroscopy & Photometry 18 II. METHODS 20-23 Meteorite Survey Databases 20 Data Selection Process 20 Data Analysis Method 21 Potential Errors 22 III. RESULTS 24-50 iv Ordinary Chondrites 24 Statistical Analysis of Ordinary Chondrites By Compositional Type 28 Peak Position to Band I Ratio 36 Statistical Analysis of Ordinary Chondrites By Metamorphic Type 42 Errors in Multiple Spectral Samples 46 IV. DISCUSSION 51-52 Importance of Study 51 Future Research Potential 52 APPENDIX 53-71 WORKS CITED 72-78 v LIST OF FIGURES Figure Page 1. Average Spectra for Ordinary Chondrites 26 2. Ordinary Chondrite Peak Wavelength Distribution 27 3. Summary Report for Ordinary Chondrite Peak Wavelength Position 29 4. Dot plot of Ordinary Chondrites 30 5. Histogram & CDF Plot of Ordinary Chondrite Peak Wavelength Positions 31 6. ANOVA One-Way Diagnostic Report OC Type Histogram & Outliers test 33 7. One-Way ANOVA Power Report for Ordinary Chondrite Peak Positions 34 8. One-Way ANOVA Summary Report for Ordinary Chondrite Peak Positions 35 9. Ordinary Chondrite Band I v Peak Position Features 37 10. Ordinary Chondrite Peak Features to Band I ratio v Band I 38 11. One-Way ANOVA Power Report for OC Peak Position to Band I Ratio 39 12. One-Way ANOVA Summary Report for OC Peak Position to Band I Ratio 40 13. Contour Plot of OC Peak Position to Band I ratio v Band I v Peak Position 41 14. LL-Type Ordinary Chondrite Peak Position Distribution 43 15. L-Type Ordinary Chondrite Peak Position Distribution 43 16. H-Type Ordinary Chondrite Peak Position Distribution 44 vi 17. Ordinary Chondrite Metamorphic Correlations 45 18. H4 Monroe 47 19. LL6 Cherokee Springs 48 20. L6 Vouille 49 21. L5 Ausson 50 vii ACKNOWLEDGMENTS I wish to express my sincere appreciation to the members of my advisory committee consisting of Dr Gaffey, Dr Whalen, and Dr Putkonen for their guidance and support during my time in the master’s program at the University of North Dakota. I would also like to express my gratitude to my advisory committee, Dr Casler, and the rest of the Space Studies department for providing much appreciated counsel and fostering my continued sense of curiosity. viii ABSTRACT Surveys in the visible to near infrared (VNIR) of main belt asteroids which cut off at the 1 micron wavelength prevent adequate characterization for approximately 2500 asteroids. This project aims at surveying spectral data from RELAB and Gaffey’s meteorite datasets utilizing the peak feature located between charge transfer and Band I of 224 ordinary chondrite (OC) samples to analyze the peak position shifts with respect to subtypes H-, L- and LL- to generate a new characterization method. This method may make it possible to unite the datasets between the meteorites and asteroids to further constrain and characterize the OC parent bodies. ix CHAPTER I INTRODUCTION Experimental Hypothesis The most prevalent class of meteorites, the Ordinary Chondrites, consists of three main compositional types (H-, L-, and LL-), yet parent bodies for the class remain unconstrained. Within the class, one well defined parent body is 6 Hebe for the H-Chondrites (Gaffey and Gilbert 1998), whereas less defined are those of the L-Chondrites, believed to be among the Gefion family (Nesvorny, et al. 2009), and the LL-Chondrites, believed to be among the Flora family (Burbine, et al. 2002). Observations of the main asteroid belt are time consuming and often are limited by atmospheric conditions. Currently there are three datasets (SMASS I, SMASS II and S3OS2) representing approximately 2500 asteroid spectra that are not viable for standard characterization (Band features) as the spectra is cut off prior to 1 micron (µm), often only 0.4-0.8 microns are useable due to high noise at the tail end of the spectra (Bus and Binzel 2003) (Binzel, et al. 2010) (Lazzaro, et al. 2006). This contraction of the sampled spectrum eliminates the possibility to characterize these asteroids based on mafic silicate composition using the Band features, where Band I is at 1 micron and Band II is at 2 microns (Gaffey 2011). As this vast resource has been impractical for anything beyond basic classification to date, a means to utilize the data obtained without the full Band I and Band II features would provide 1 the means to exploit the SMASS I, SMASS II and S3OS2 databases in order to potentially locate possible parent bodies for the Ordinary Chondrites. The peak feature (0.6-1.0 µm) between the charge transfer and Band I feature may shift characteristically as the Band I feature itself does. The peak feature (0.6-1.0 microns) shares a limb with the Band I feature, thus utilizing meteorite spectra for Ordinary Chondrites will illustrate this peak shift dependent on the type of Ordinary Chondrite, potentially creating a novel characterization method allowing one to search for assemblages mirroring that of the type of Ordinary Chondrite in the search for possible parent bodies. The potential usage for such a characterization method may exceed the anticipated usage for Ordinary Chondrites to potentially aid use as a tool for other asteroid spectral classes as well. In short, the hypothesis of this study is that by developing a calibration tool utilizing the peak feature between 0.6 and 1.0 microns will allow for the identification and statistical differentiation of individual classes of Ordinary Chondrites. Meteorites "A meteorite is a natural object that survives its fall to Earth from space” (Hutchinson 2004), however this natural object is also representative of larger bodies that have been disrupted and put into an Earth crossing orbit (Gaffey 2011). A number of factors determine whether an object will survive atmospheric entry, such as: size, entry angle, velocity, composition, internal integrity, and density. It is estimated from sky photography and photometry that 13,700 meteorites between 100 g and 1 kg and 4,500 meteorites larger than 1 kg survive atmospheric entry annually (Hutchinson 2004). Photography and photometry picks 2 up fireballs that are relatively bright. The fireball is generated by friction as the object enters the atmosphere and experiences drag. Calculations show the influx of material that is traceable, which means the object is larger than 100 g in order to generate a large enough flare have been included while smaller objects are not represented by these influx estimates (Hutchinson 2004). Objects enter Earth’s atmosphere between 11 and 73 km/s depending on the approach and entry angle; 93% of the meteorites that survive entry are stony consisting mostly of Olivine and Pyroxene with a density between 3.0 and 3.5 g/cm3.