Japetus is mentioned in Legacy as the second moon of Jupiter c.3900 AD
when, in fact, Iapetus is the 6th moon of Saturn. Sadly, this
discrepancy wasn't picked up when Stephen Cole reordered the Solar
System c.2338 AD, so it explicitly wasn't mentioned as one of Jupiter's
moons in that story.

Presumably, following the destruction of Carme, one of the "Ancient
Twelve" moons in To the Slaughter, Iapetus was moved into Jupiter's
orbit and henceforth referred to as Japetus.

AD