My favourite space opera of all time (Perry Rhodan) has us coming from
Earth and, in fact, the series starts off with the titular character
landing on the moon in the first moon mission. Another space opera I
enjoyed, however (Neverness) has Earth basically a lost place
remembered only in vague legends. People came from Earth originally
but so long ago and so far away that nobody really knows where it is
or how many of the stories about it were true.