Space weather and interplanetary shocks
نویسندگان
چکیده
São discutidos nesse artigo alguns conceitos básicos relacionados ao clima espacial no ambiente próximo da Terra. Devido ao desenvolvimento tecnológico dos anos recentes, o clima espacial tornou-se um tema importante de pesquisa. Os avanços da área se devem principalmente à sua aplicabilidade nos sistemas tecnológicos tanto no espaço próximo quanto na superf́ıcie da Terra. Dentre os diversos temas abordados pelo clima espacial está a investigação de como perturbações no meio interplanetário, decorrentes da variabilidade solar, afetam o campo magnético da Terra. Os efeitos de tais variações podem ser observados em solo através de medidas de magnetômetros e no espaço próximo à Terra, por exemplo, as auroras. Alguns aspectos de uma perturbação solar em particular, a saber choques interplanetários, são brevemente revisados. Um evento real com atividade geomagnética intensa é simulado por um código magneto-hidrodinâmico (MHD). Resultados da simulação numérica concordam bem com dados observados por magnetômetros em solo. A importância de simulações globais MHD no desenvolvimento de modelos de previsão de clima espacial é enfatizada. Palavras-chave: clima espacial, interações magnetosfera-ionosfera, simulações numéricas e observações.
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تاریخ انتشار 2016