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@PhDThesis{Mota:2018:MoCaGr,
               author = "Mota, Marcelo Lisb{\^o}a",
                title = "Modelo do campo gravitacional de um corpo com 
                         distribui{\c{c}}{\~a}o de massa irregular utilizando o 
                         m{\'e}todo da expans{\~a}o do potencial em s{\'e}rie e 
                         determina{\c{c}}{\~a}o de seus coeficientes dos harm{\^o}nicos 
                         esf{\'e}ricos",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-12-14",
             keywords = "campo gravitacional, expans{\~a}o do potencial em s{\'e}rie, 
                         concentra{\c{c}}{\~o}es de massa, harm{\^o}nicos 
                         esf{\'e}ricos, gravitational field, expansion of the potential in 
                         series, concentrations of mass, spherical harmonics.",
             abstract = "O objetivo geral deste trabalho foi estabelecer uma metodologia 
                         para determinar o modelo do campo gravitacional em torno de um 
                         corpo com distribui{\c{c}}{\~a}o de massa irregular, utilizando 
                         o m{\'e}todo da expans{\~a}o do potencial em s{\'e}rie, 
                         ap{\'o}s a sua decomposi{\c{c}}{\~a}o em elementos 
                         tetra{\'e}dricos, calculando-se o seu potencial total, como o 
                         somat{\'o}rio dos potenciais relativos a cada tetraedro. Com este 
                         prop{\'o}sito, primeiramente, foi modelado o campo gravitacional 
                         gerado por um cubo homog{\^e}neo unit{\'a}rio e, em seguida, e 
                         os resultados obtidos foram comparados e validados com aqueles 
                         apresentados pelo modelo exato desse hexaedro. De posse do modelo, 
                         foram determinados seus coeficientes dos harm{\^o}nicos 
                         esf{\'e}ricos, tamb{\'e}m ratificados pelos resultados 
                         existentes na literatura. A partir da valida{\c{c}}{\~a}o desta 
                         t{\'e}cnica para o cubo homog{\^e}neo, procurou-se 
                         aplic{\'a}-la na modelagem dos campos gravitacionais dos 
                         asteroides (25143) Itokawa, (1620) Geographos e (433) Eros, 
                         utilizando os dados reais disponibilizados pelo JPL/NASA, 
                         produzindo resultados consistentes quando comparados com aqueles 
                         apresentados na literatura. Utilizando o mesmo procedimento 
                         adotado para o cubo, tamb{\'e}m foram calculados os coeficientes 
                         de Stokes para esses asteroides at{\'e} o grau 6, al{\'e}m de 
                         realizar simula{\c{c}}{\~o}es de {\'o}rbitas em torno desses 
                         asteroides, utilizando os modelos obtidos pelos m{\'e}todos da 
                         expans{\~a}o do potencial em s{\'e}rie e 
                         concentra{\c{c}}{\~o}es de massa, com o intuido de 
                         compar{\'a}-las. Al{\'e}m desses asteroides citados, tamb{\'e}m 
                         foram modelados os potenciais dos asteroides (2063) Bacchus, 
                         (101955) Bennu, (1580) Betulia, (4769) Castalia, (21) Lutetia e 
                         (4660) Nereus, cujos coeficientes dos harm{\^o}nicos 
                         esf{\'e}ricos constam dos ap{\^e}ndices deste trabalho. 
                         ABSTRACT: The general objective of this work was to establish a 
                         methodology to determine the gravitational field model around a 
                         body with irregular mass distribution, using the method of 
                         expansion of the potential in series, after its decomposition in 
                         tetrahedral elements, calculating its potential, as the sum of the 
                         potentials relative to each tetrahedron. For this purpose, 
                         initially, the gravitational field produced by a unitary 
                         homogeneous cube was modeled. The results obtained for the cube 
                         were compared and validated with those presented by the exact 
                         model of this hexahedron. Then, with the model, its coefficients 
                         of the spherical harmonics, which also ratified by the results in 
                         the literature, were determined. From the validation of this 
                         technique for the homogeneous cube, the same technique was applied 
                         in the modeling of the gravitational fields of the asteroids 
                         (25143) Itokawa, (1620) Geographos and (433) Eros, with the actual 
                         data provided by JPL / NASA, producing consistent results compared 
                         to those presented in the literature. Using the same procedure 
                         adopted for the cube, we also calculated the Stokes coefficients 
                         for these asteroids up to order 6. Simulations of trajectories 
                         around these asteroids were performed, using the models obtained 
                         by the expansion of the potential in series and by the 
                         concentrations of masses, with the intention of comparing them. In 
                         addition, were also modeled the gravitational fields of the 
                         asteroids (2063) Bacchus, (101955) Bennu, (1580) Betulia, (4769) 
                         Castalia, (21) Lutetia and (4660) Nereus, whose spherical harmonic 
                         coefficients were included in the appendices of this work.",
            committee = "Pilchowski, Hans-Ulrich (presidente) and Rocco, Evandro Marconi 
                         (orientador) and Moraes, Rodolpho Vilhena de and Carvalho, 
                         Francisco das Chagas and Costa Filho, Aguinaldo Cardozo da",
         englishtitle = "Model of the gravitational field of a body with irregular mass 
                         distribution using the method of the potential expansion in 
                         series, and the determination of their spherical harmonic 
                         coefficients",
             language = "pt",
                pages = "277",
                  ibi = "8JMKD3MGP3W34P/3PQ2FAB",
                  url = "http://urlib.net/ibi/8JMKD3MGP3W34P/3PQ2FAB",
           targetfile = "publicacao.pdf",
        urlaccessdate = "27 abr. 2024"
}


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