is there a museum here?
Yes, the National Museum.
Paço de São Cristóvão
the National Museum was transferred to the old Imperial Palace of São Cristóvão in 1892. 
who was afonso? Prince Imperial and heir apparent to the throne of the Empire of Brazil. when was he born? 23 February 1845 who was he to successor of? Pedro II did he live in a palace? Yes, Palace of São Cristóvão. when was it built? UNANSWERABLE where is it located? Quinta da Boa Vista park in the Imperial Neighbourhood of São Cristóvão, Rio de Janeiro, Brazil. apart from the royals who else resides in this palace? Brazilian Imperial Family
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Paço de São Cristóvão [SEP] National Museum
Founded in 1818 by King John VI of Portugal, the National Museum was transferred to the old Imperial Palace of São Cristóvão in 1892. During its long history, its collections have been greatly expanded by acquisitions and donations, including by Emperor Pedro II, a great sponsor of the sciences. The collections included Astronomy (mostly meteorites), Palaeontology, Natural history, Ethnology (including many interesting works by Brazilian indigenous peoples) and Archaeology (mostly antiquities from ancient Egypt). Much of the art collection displayed by the Museum still consisted of what was gathered by the Emperor Pedro II himself. In this manner, it reflects 19th-century views of Anthropology, Archeology and sciences in general.