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dc.contributor.advisorRieke, Georgeen_US
dc.contributor.authorCAMEJO, HUMBERTO CAMPINS.*
dc.creatorCAMEJO, HUMBERTO CAMPINS.en_US
dc.date.accessioned2011-10-31T17:32:30Zen
dc.date.available2011-10-31T17:32:30Zen
dc.date.issued1982en_US
dc.identifier.urihttp://hdl.handle.net/10150/185260en
dc.description.abstractInfrared photometry has been used to determine the physical characteristics of cometary solids. Observations were made of the reflected and thermal parts of the spectra of seven comets. Two of these comets, Bowell and West, were nonperiodic; the other five, Chernyhk, Encke, Kearns-Kwee, Stephan-Oterma, and Tuttle, were periodic. Observations in the 3 μm region of the spectrum of Comet Bowell provide the first direct evidence for the presence of H₂O ice in a comet. This detection represents one of the strongest possible confirmations of Whipple's (1950) icy conglomerate model of cometary nuclei. The observations of the periodic comets have yielded the following picture of the dust in this type of objects: grains with a size distribution ranging from about 0.3 μm to 10 μm, and peaking around a few microns. These grains were made up of at least two components, a silicate material and an absorbing material. These characteristics are remarkably similar to those of the dust in nonperiodic comets. This indicates that the type of dust a comet ejects does not change with age, and supports the absence of large scale differentiation in cometary nuclei. Comet West is the first case of a splitting comet in which the fragments were observed to have differences in their dusty component. These observations suggest that the nucleus of this comet did not have an "onion skin" or layered structure but rather had pockets containing dust grains with different size distributions. Based on the results presented, the relation between cometary and interstellar dust, and the origin of comets are discussed.
dc.language.isoenen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © 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.en_US
dc.subjectComets -- Spectra.en_US
dc.subjectCosmic dust.en_US
dc.subjectAstronomical photometry.en_US
dc.titleINFRARED OBSERVATIONS OF COMETARY SOLIDS.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.identifier.oclc688223915en_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.leveldoctoralen_US
dc.identifier.proquest8306449en_US
thesis.degree.disciplinePlanetary Scienceen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.namePh.D.en_US
refterms.dateFOA2018-06-15T19:43:25Z
html.description.abstractInfrared photometry has been used to determine the physical characteristics of cometary solids. Observations were made of the reflected and thermal parts of the spectra of seven comets. Two of these comets, Bowell and West, were nonperiodic; the other five, Chernyhk, Encke, Kearns-Kwee, Stephan-Oterma, and Tuttle, were periodic. Observations in the 3 μm region of the spectrum of Comet Bowell provide the first direct evidence for the presence of H₂O ice in a comet. This detection represents one of the strongest possible confirmations of Whipple's (1950) icy conglomerate model of cometary nuclei. The observations of the periodic comets have yielded the following picture of the dust in this type of objects: grains with a size distribution ranging from about 0.3 μm to 10 μm, and peaking around a few microns. These grains were made up of at least two components, a silicate material and an absorbing material. These characteristics are remarkably similar to those of the dust in nonperiodic comets. This indicates that the type of dust a comet ejects does not change with age, and supports the absence of large scale differentiation in cometary nuclei. Comet West is the first case of a splitting comet in which the fragments were observed to have differences in their dusty component. These observations suggest that the nucleus of this comet did not have an "onion skin" or layered structure but rather had pockets containing dust grains with different size distributions. Based on the results presented, the relation between cometary and interstellar dust, and the origin of comets are discussed.


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