UB313 is a dwarf planet outside the orbit of Pluto. The discovery team nicknamed it Xena, because ‘we have alway wanted to name something Xena’. In case there’s any doubt about where the name came from, its moon was nicknamed Gabrielle. I never particularly watched the warrior princess (my hormones hadn’t quite kicked in when it started :-)) but it turns up surprisingly often on the internet.
I was hoping Xena would become the official name, but sadly the IAU has just officially officially named it Eris, after the greek goddess of strife. However, the Bad Astronomer points out that the moon is called Dysnomia – the child of Eris and god of lawlessness. Xena was played by Lucy Lawless…Could be a coincidence, but probably not 🙂
There will undoubtedly be many more Eris-sized objects found, so plenty of scope for geeky jokes. I’m sure there’s scope for a ST:TNG reference somewhere. Guinan? Marina? Locutus!
Update: Also see Skeptico’s write-up of the astrological implications of the name change.