The International Astronomical Union has rejected the first choice of voters for naming Pluto’s fourth and fifth moons.

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The International Astronomical Union (IAU) has picked names for Pluto’s fourth and fifth moons, rejecting Vulcan, the first choice of the public.

After the discovery [of the moons], the leader of the research team, Mark Showalter (SETI Institute), decided to call for a public vote to suggest names for the two objects. To be consistent with the names of the other Pluto satellites, the names had to be picked from classical mythology, in particular with reference to the underworld — the realm where the souls of the deceased go in the afterlife. The contest concluded with the proposed names Vulcan, Cerberus and Styx ranking first, second and third respectively. Showalter submitted Vulcan and Cerberus to the IAU where the Working Group for Planetary System Nomenclature (WGPSN) and the Committee on Small Body Nomenclature (WGSBN) discussed the names for approval.

However, the name Vulcan had already been used for a hypothetical planet between Mercury and the Sun. Although this planet was found not to exist, the term “vulcanoid” remains attached to any asteroid existing inside the orbit of Mercury, and the name Vulcan could not be accepted for one of Pluto’s satellites (also, Vulcan does not fit into the underworld mythological scheme). Instead the third most popular name was chosen — Styx, the name of the goddess who ruled over the underworld river, also called the Styx.

I just can’t wait until there really is a robust population of space-faring colonists, if only because those colonists will then tell the IAU to go to hell when it tries to tell them what to name things.



  • mike shupp

    I’m quite pleased with the this ruling — I still think of Pluto as being the 9th planet, so I trust you will understand I’m not an IAU toady.

    40 Eridani A, classically known as Keid, is a star with a K1 spectral classification about 17 light years from earth. It’s a neighbor, so to speak. It really exists. It very likely has some planets, and it’s also likely that one or more of those planets will be located in the habitable zone of that star. In the fictional Star Trek universe, there is such a planet, and it’s named Vulcan. It has acquired a certain amount of cultural resonance — there are probably more people around the globe today who identify Vulcan as the homeworld of Mr Spock than there ever were who knew Vulcan as the lamed backsmith of the gods, husband of Venu, cuckolded by Mars..

    Vulcan was a major deity, once upon a time, I’m saying. And the name still has Power. We shouldn’t waste it on a penny ante satellite of Pluto. Let’s save it for something more worthy — like a planet which astronomers might eventually observe in the habital zone of 40 Eridani A. Or –better yet — for a planet about 40 Eridani A colonized by people from earth.

  • Actually, I agree with you about Vulcan and saving that name for a better place. However, I am repeatedly infuriated by the IAU’s pompous dictatorial insistence that the name of every object in space must be approved by it. They really don’t have that power or right. Their naming rights stem originally from the need of astronomers to have some organized system for naming the literally millions of objects they discover. The IAU should confine itself to that and shut up the rest of the time.

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