ORGANIZATION@1 : ORGANIZATION@2 NUMBER@1 , NUMBER@2 -- NUMBER@3 Nevertheless , a MISC@1 historian of astronomy , PERSON@1 , claimed that the MISC@1 astronomer MISC@2 observed one of LOCATION@1 's moons in NUMBER@4 BC , nearly NUMBER@5 millennia earlier than Galileo .

ORGANIZATION@1 : ORGANIZATION@2 NUMBER@1 , NUMBER@6 . A MISC@1 historian of astronomy , PERSON@1 , claims that MISC@1 astronomer Gan De observed one of LOCATION@1 's moons in NUMBER@4 BC , nearly NUMBER@5 millennia earlier than Galileo .
