• Login
    View Item 
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    The collisional and dynamical evolution of asteroids.

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    azu_td_9531143_sip1_m.pdf
    Size:
    5.901Mb
    Format:
    PDF
    Description:
    azu_td_9531143_sip1_m.pdf
    Download
    Author
    Bottke, William Frederick, Jr.
    Issue Date
    1995
    Committee Chair
    Greenberg, Richard
    
    Metadata
    Show full item record
    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.
    Abstract
    Understanding asteroid collisional and dynamical evolution necessitates the use of statistical methods, since an asteroid's physical and orbital characteristics are modified throughout its lifetime by collisions and planetary perturbations. Thus, my thesis investigates evolutionary trends for asteroids by calculating and applying parameters such as collision probabilities, impact velocities, and collisional and dynamical lifetimes. I found that previous calculations of collision probabilities between pairs of asteroids on independent Keplerian orbits often yielded inconsistent results. By correcting and improving the formalism, I obtained results which should be accurate for all cases. Applying this formalism, I calculated collision probabilities and impact velocity distributions for single asteroids (e.g. Gaspra, Ida), asteroid populations, and the terrestrial planets with other asteroid populations. These results allowed me to determine asteroid comminution and planetary impact rates. I also examined the dynamical evolution of asteroids, using a modified Monte-Carlo code. The accuracy of these codes are frequently questioned since, for some planetary encounters on tangential orbits, the two-body scattering approximation is inconsistent with numerical integration results. Thus, to verify the validity of Monte-Carlo results in general, I tracked particle-planetary encounters using a new mapping technique to determine the role of distant perturbations. My results show that Monte-Carlo results yield statistically similar results to numerical integration for all but the most pathological cases, and my model shows why. Finally, I used this Monte-Carlo model, modified to include impact disruption, asteroid fragmentation after disruption, and observational selection effects to determine the most likely source for a population of small asteroids near the Earth. My results show that main-belt asteroids (via the 3:1 or v₆ resonances) are an unlikely source for these objects, as are small bodies ejected from Mars after a large cratering event. However, planetary ejecta from either the Earth-Moon system or Venus is dynamically consistent with these orbits. Of these three, the Moon is the most likely source since its escape velocity is significantly lower than either Earth or Venus.
    Type
    text
    Dissertation-Reproduction (electronic)
    Degree Name
    Ph.D.
    Degree Level
    doctoral
    Degree Program
    Planetary Sciences
    Graduate College
    Degree Grantor
    University of Arizona
    Collections
    Dissertations

    entitlement

     
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.