"My aunt comes from the moon."
Translation:Tante saya datang dari bulan.
I think this just might be a valid yet poor translation due to not enough context. "Berasal" means origin (as in born there), and the English sentence is a bit ambiguous without the context, does it mean your aunt originates from the moon or she comes (to you) after visiting the moon?
The Indonesian sentence use of "datang" implies the latter, still personally it sounds weird to me. We normally say "Tante saya datang setelah dari bulan"