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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Tidal evolution of Pluto-Charon and the implications for the origin ofthe satellites Nix and Hydra

Cheng, Wing-hong., 鄭穎康. January 2011 (has links)
published_or_final_version / Earth Sciences / Master / Master of Philosophy
2

LIGHTCURVE CCD SPECTROPHOTOMETRY OF PLUTO.

BUIE, MARC WILLIAM. January 1984 (has links)
An observational program was carried out to investigate the spectrum of Pluto at various points on its lightcurve. Spectrophotometry of Pluto in the wavelength range of 5600 to 10500 Å was obtained on four nights covering lightcurve phases of 0.18, 0.35, 0.49, and 0.98. The four phases included minimum light (0.98) and one near maximum light (0.49). The spectra reveal variations in the adsorption depths of the methane bands at 6200, 7200, 7900, 8400, 8600, 8900, and 10000 Å. The minimum amount of adsorption was found to occur at minimum light. A model for the surface and atmosphere of Pluto was constructed in an attempt to explain the phase variation observed. The model is based upon a previous photometric two-spot model which was constructed to explain the variations in the lightcurve from 1950 to 1982. Two dark circular spots (46° and 28° in radius, both at latitude -23°, separated by 134° in longitude) were used to constrain the surface distribution of methane frost on the surface of Pluto. The reflectance properties of the two terrains were modelled with a theory by B. Hapke (J.G.R., v. 86, p. 3039, 1981) which includes the effects of multiple scattering in the surface frost. The particle size and continuum optical depth of the frost particles were allowed to vary between the dark regions inside the spot boundaries and the brighter regions surrounding the spots. The transmission of the atmosphere was calculated using the Mayer-Goody band model. The model fit to the spectrum required the presence of a frost with particle sizes on the order of 1-20 mm in order to explain the observed phase dependence of the methane bands. Using only the atmosphere and no surface frost implies a variation in column abundance of 30% within three days. From energy balance considerations this variation in column abundance is not possible. By including the absorption of methane frost on the surface a range of model solutions was obtained. This range yields an approximate limit of 5.5 m-amagats to the amount of gas that can be present and still achieve a good fit to the phase variation of the 7200 Å band. If the atmosphere is removed from the model an equally good fit to the 7200 Å band is obtained. A major problem with the model is its failure to reproduce the relative absorption band depths. The gaseous atmospheric calculation on the other hand can fit the spectrum quite well. Possible explanations include a particle size distribution within a given terrain.
3

Sputnik Planitia as a probe for Pluto’s internal evolution.

Camille Adeene Denton (14216183) 06 December 2022 (has links)
<p>  </p> <p>Though we cannot directly characterize the internal structure of Pluto, its interior can be probed remotely by observing its response to impact-induced deformation. The formation and evolution of giant impact basins like Sputnik Planitia, Pluto’s massive 1200 x 1400-km-diameter impact basin, is a unique geologic process that links the dwarf planet’s interior structure to the basin’s morphology and overall longevity. Its large size, location, and relationship to tectonic features has led researchers to suggest that Sputnik Planitia preserves evidence of a large subsurface ocean, while possible antipodal features observed on Pluto’s far side raise questions of how stress waves from impact may have traveled through Pluto’s interior, which remains somewhat unconstrained. In this dissertation, I strive to understand the relationship between the formation and evolution of Sputnik Planitia and the thermal and mechanical structure of Pluto at a variety of scales. The years following New Horizons’ flyby of the Pluto system in 2015 have yielded more questions than answers about the state of Pluto’s interior, including the thickness and thermal structure of its ice shell, the possible presence of a liquid water ocean, and the composition of its rocky core. I use impact simulations to reproduce the unique physics associated with impact cratering and further investigate which internal structures are consistent with the cratering record, as well as finite element models to explore the postimpact evolution of Pluto’s largest impact basin and probe the mechanical and thermal structure of the ice shell in more detail. With these tools, I show that the formation and evolution of Sputnik Planitia is consistent with the presence of a hydrated core and thick subsurface ocean in Pluto’s interior. The results of this dissertation contribute to understanding the origin, evolution, and interior of Pluto as well as other icy moons, ocean worlds, and large Kuiper Belt Objects in our solar system, and has direct implications for future exploration of other such worlds in our solar system.</p>
4

Numerical Evidence that the Motion of Pluto is Chaotic

Sussman, Gerald Jay, Wisdom, Jack 01 April 1988 (has links)
The Digital Orrery has been used to perform an integration of the motion of the outer planets for 845 million years. This integration indicates that the long-term motion of the planet Pluto is chaotic. Nearby trajectories diverge exponentially with an e-folding time of only about 20 million years.
5

Strojírna a slévárna Jan Pujman (Pluto) v Novém Ransku v první polovině 20. století / Foundry and machinery factory Jan Pujman (Pluto), Nové Ransko in first half of the 20 century

Monev, Ivan January 2019 (has links)
(in English): The Diploma Thesis is focused on the issue of the management methods in the company, engaged in the production of agricultural machinery in the period of the Czechoslovak Republic. It is particularly concerned with the process of business management, trade promotion, customers' relationship and reflection of these activities into the company's economy. The Thesis is focused mostly on the Czech and Bulgarian business activity documentation. The data for this Thesis was obtained by direct research of the original, till this time unresearched archival sources, by personal memories of witnesses, desk research of relevant archive documents and literature. The data analysis performed at the end of the Thesis used the current business analysis methods for comparing reporting and present period's marketing methods. The researched subject is Jan Pujman machinery and engines company and cast iron producer, founded by Jan Pujman senior in the year 1885 in Nové Ransko, whose activities were terminated by The Nationalization in April 1949.
6

Relaxace impaktních kráterů ve sluneční soustavě / Impact crater relaxation throughout the Solar System

Kihoulou, Martin January 2021 (has links)
Title: Impact crater relaxation throughout the Solar System Author: Martin Kihoulou Department: Department of Geophysics Supervisor: RNDr. Klára Kalousová, Ph.D., Department of Geophysics Abstract: In this thesis, we study the viscous relaxation of an impact-deformed icy shell of a dwarf planet Pluto. Motivation for this work is the position of Sputnik Planitia, a 1000 km wide, nitrogen-filled elliptic basin, which is located very close to Pluto-Charon tidal axis. Given this unlikely position on Pluto's sur- face, it was suggested that the basin was formed elsewhere and the whole body reoriented afterwards. For the reorientation to occur, the basin has to generate a positive gravity anomaly for which a combination of impact-related subsurface ocean uplift, ejecta blanket and accumulation of nitrogen ice was suggested. How- ever, to maintain the orientation towards the minimum principal axis of inertia until today, the ocean uplift must be present on timescales of billions of years, which may be achieved due to an insulating layer of high viscosity clathrates at the ice/ocean interface. We solve Pluto's ice shell evolution by the finite element method in 2D spherical axisymmetric geometry with an evolving free surface and assuming a viscous rheology. Our results show that the thermal effect of the im- pact...
7

Análise da estabilidade da região externa do sistema Plutão-Caronte após a descoberta dos novos satélites NIX e HIDRA: aplicação à sonda new horizons

Santos, Pryscilla Maria Pires dos [UNESP] 10 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-10Bitstream added on 2014-06-13T18:53:34Z : No. of bitstreams: 1 santos_pmp_me_guara.pdf: 4359750 bytes, checksum: 85e5035af4f1d67cd7f1b2afa6bc956a (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Neste trabalho analisamos numericamente a região externa do sistema Plutão-Caronte através da insercão de partículas-teste inicialmente em ´orbitas do tipo-P prógradas e retrógradas, no sistema formado por Plutão, Caronte, Nix e Hidra. Destas integracões numéricas foram geradas grades semi-eixo maior em função da excentricidade definindo-se regiões de partículas em orbitas estáveis e regiões de colisão e escape. Na vizinhança dos satélites Nix e Hidra foram identificadas regiões caóticas, em que partículas localizadas dentro desta região têm suas excentricidades e semi-eixo maiores aumentados e escapam ou colidem com um corpo massivo do sistema. Um conjunto de partículas permaneceram em regiões próximas das orbitas de Nix e Hidra, possivelmente coorbitais de Nix e Hidra. Para ambos os casos, prógrado e retrógrado, a região estável”é maior na região externa do sistema, após a órbita de Hidra, dependendo do valor da excentricidade. Também foram realizadas simulações numéricas inserindo satélites hipotéticos massivos além da órbita de Caronte e os efeitos causados nas órbitas de Nix e Hidra foram analisados. Um estudo numérico preliminar dos efeitos da Press˜ao de Radiac¸ ˜ao Solar em partículas com raios de 1μm, 3μm, 5μm e 10μm foi realizado. Este estudo mostrou que partículas sob os efeitos do Arrasto de Poynting-Robertson deca´ıram em 1,45 × 106 anos (partículas de 1μm de raio) e 1,45 × 107 anos (partíıculas de 10μm de raio), enquanto que a Pressão de Radiac¸ ˜ao causou variacões das excentricidades das partículas fazendo com que em alguns casos houvesse colisões com o planeta. / In this work we performed a numerical analysis of the the outer region of the Pluto-Charon system by the insertion of a sample of test particles initially in P-type prograde and retrograde orbits, in the system formed by Pluto, Charon, Nix and Hydra. These numerical integrations generated diagrams of semi-major axis versus eccentricity which define regions of particles in stable orbits and regions of collision and escape. In the vicinity of the satellites Nix and Hydra were identified chaotic regions, where particles located in this region have their eccentricities and semi-major axis increased provoking an ejection or collision with a massive body of the system. A set of particles remained in regions near the orbits of Nix and Hydra, possibly coorbitais with them. For both cases, prograde and retrograde, the “stable” region is larger in the outer region of the system, after Hydra’s orbit, depending on the value of eccentricity. Numerical simulations were also performed by inserting some massive hypothetical satellites beyond the Charon’s orbit and the effects on the orbits of Nix and Hydra were analyzed. A preliminary numerical study of the effects of the solar radiation force on a sample of particles with radii of 1μm, 3μm, 5μm e 10μm was performed. This study showed that particles under the effects of the Poynting-Robertson drag decay on a time scale between 1.45×106 years (particles of 1μm in radius) and 1.45×107 years (particles of 10μm in radius), while the radiation pressure caused variations of the eccentricities of the particles causing in some cases collisions with the planet.
8

Regiões de estabilidade no sistema Plutão-Caronte

Guimarães, Ana Helena Fernandes [UNESP] 08 August 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-08Bitstream added on 2014-06-13T18:49:26Z : No. of bitstreams: 1 guimaraes_ahf_me_guara.pdf: 2381225 bytes, checksum: 8019dfa6ffed11e95f9f5a24914be192 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / Plutão e Caronte, bem como os novos satélites do sistema, Nix e Hidra, são alvos de micrometeoritos, provavelmente originários do cinturão de Kuiper. Os resíduos destes impactos permaneceriam no sistema em órbitas ao redor de Plutão ou Caronte. Este estudo analisa, através de simulações numéricas, a estabilidade das regiões ao redor do sistema binário. Esta análise deu-se através de simulações numéricas para o problema restrito de três corpos. Foram numericamente integradas órbitas para partículas ao redor de Plutão, ao redor de Caronte e ao redor do baricentro do sistema. Dessas integrações numéricas foram geradas grades a x e, definindo-se regiões: de estabilidade, de escape e de colisão. A região estável ao redor de Plutão vai até aproximadamente 8200km, ao redor de Caronte se estende até 2900km e ao redor do baricentro do sistema binário, órbitas Tipo-P, a região estável inicia-se a partir de 49000km. Estes valores estão de acordo com a teoria de Holman e Wiegert (1999). As regiões de estabilidade de Plutão Caronte foram também amplamente estudadas através do uso da Superfície de Secção de Poincaré (SSP). Um conjunto de cerca de 230 SSP foi obtido. Foram gerados diagramas de Cjxx, Cj é o valor da Constante de Jacobi, derivados das SSP para a região interna aos corpos massivos do binário e externa a eles. Estes diagramas representam a síntese da análise da estabilidade por meio das SSP. Neles ficam determinadas as regiões estáveis às partículas no sistema. Cojuntos especiais de SSP foram gerados para análise das ressonâncias 1:6 e 1:4, pois estas, em especial, estariam relacionadas aos novos satélites. Verificou-se que estes satélites estão em regiões estáveis, mas não em ressonância de acordo com o dados até hoje conhecidos. / Pluto and Charon and the two new discovered satellites, named Hydra and Nix, are targets of micrometeorites which were probably originated from the Kuiper belt. A sample of particles can be generated from these collision and be trapped in orbit around Pluto or Charon. This work analyses, through numerical simulations, the stable regions around the binary system. This analysis took into account the Restricted Three Body Problem. From these numerical simulations diagrams of a x e were generated defining, stable, escape and unstable regions. Stable regions around Pluto (width about 8200km), around Charon (width about 2900km) and around the baricentre of the binary system (after a semi-major axis about 49000km) were obtained. These values are in good agreement with the work by Holman & Wiegert (1999). These stable regions were also analysed by using the technique of POincaré Surface of Section (PSS). A sample of about 230 PSS was obtained. In all these PSS chaotic and stable regions and also the resonance locations were identified. Diagrams of Cj x x, derived from the PSS, were obtained. They represent the synthesis of the stability region acquired from the PSS. A particular set of SSP was generated in order to analyse the evolution of 1:4 and 1:6 resonances. The new satellites, Hydra and Nix, are located in stable regions although, they are not in resonances with Charon, as can be seen in the grade a x e.
9

Origem e estabilidade de satélites planetários: alguns casos peculiares / Origin and stability of planetary satellites: some peculiar cases

Luiz, André Amarante 19 September 2017 (has links)
Submitted by Andre Amarante Luiz null (amarante@feg.unesp.br) on 2018-02-11T19:52:31Z No. of bitstreams: 1 A_Amarante__O_C_Winter__M_Tsuchida.pdf: 9049058 bytes, checksum: a87f695e2060e08b5657bf5c4106d282 (MD5) / Approved for entry into archive by Pamella Benevides Gonçalves null (pamella@feg.unesp.br) on 2018-02-14T10:49:37Z (GMT) No. of bitstreams: 1 amarante_a_dr_guara.pdf: 9049058 bytes, checksum: a87f695e2060e08b5657bf5c4106d282 (MD5) / Made available in DSpace on 2018-02-14T10:49:37Z (GMT). No. of bitstreams: 1 amarante_a_dr_guara.pdf: 9049058 bytes, checksum: a87f695e2060e08b5657bf5c4106d282 (MD5) Previous issue date: 2017-09-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A origem e estabilidade de satélites planetários estão, intimamente ligadas à origem do nosso Sistema Solar e à formação de planetas. Portanto, é apropriado estudar alguns casos peculiares para nossa compreensão atual sobre a formação do Sistema Solar e para entender a criação dos sistemas de satélites. Tendo isso em vista um estudo da estabilidade dos satélites internos de Urano é realizado procurando viabilizar um cenário estável para tal sistema. Nós encontramos um provável cenário que possa nos dar indícios de que o sistema de satélites internos de Urano possa ser estável. Outro cenário importante para compreender a formação de satélite é o estudo de nosso próprio satélite natural, a Lua. O estudo da origem a Lua é realizado através de uma rápida revisão bibliográfica das teorias de origem da Lua e com isso tentamos analisar qual seria o cenário mais provável de colisão dentro da teoria do Grande Impacto que favorece a formação do nosso satélite, levando em conta suas características físicas, químicas e petrológicas. O cenário mais provável foi aquele em que colisões com massas comparáveis são usadas para se originar a Lua. O estudo da estabilidade de coorbitais dos pequenos satélites do sistema binário Plutão-Caronte é importante visto que também é um caso de cenário de formação de satélites peculiares no Sistema Solar. O estudo dessa estabilidade nos levou a indícios de que o sistema não possui coorbitais à suas pequenas luas, fato comprovado até agora pela missão New Horizons. / The origin and stability of planetary satellites are closely linked to the origin of our Solar System and the formation of planets. Therefore, it is appropriate to study some peculiar cases to our current understanding of the formation of the Solar System and to understand the origin of satellite systems. In order to study the stability of the internal satellites of Uranus, in order to provide a stable scenario for such a system. We have found a probable scenario that allows the internal uranian system get stable. Another important scenario for the formation of satellites is the moon scenario. The study of the origin of the Moon is made through a revised bibliographical revision of the theories of origin of the Moon and with this we try to analyze which forming the most probable collision within the theory of Great Impact that favors a formation of our satellite, taking into account its physical, chemical and petrological characteristics. The most likely scenario was that collisions with comparable masses are used to originate the Moon. The study of coorbital stability of the small satellites of the Pluto-Charon binary system is important since it is also a case of a peculiar satellite formation scenario in Our Solar System. The study of stability has led us to evidence that the system is not coorbitary in its small moons, a fact proven so far by the New Horizons mission
10

Transneptunická tělesa / Transneptunian objects

PIHERA, Martin January 2009 (has links)
Main goal of this diploma is to create an essential summary of a current state in the field of transneptunian objects. This review enables understanding the findings about the transneptunian objects. The summary creates a review of advance and progress tendency in research in the area of transneptunian objects.

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