The fourth and fifth moon of Pluto was officially called by popular vote Kerberos and Styx, respectively, said today the International Astronomical Union (IAU).
The moons, discovered in 2011 and 2012 were known at first as P4 and P5, but the team leader responsible for the discovery, made by Hubble telescope observations from NASA, decided to organize a contest to baptize.
The International Astronomical Union routinely advises researchers in the process of naming the celestial bodies and is also responsible for checking that the chosen words have no problem in the different languages and cultures, to avoid confusion.
In this case, to be consistent with the names of the other satellites of Pluto, Charon, Nix and Hydra, are asked the audience to the names were related to classical mythology, especially the place we were going to stop the souls of the dead.
The contest ended with the names of Vulcan, Cerberus and Styx at the top of the list and the discovery team referred to the IAU the Vulcan and Cerberus to his analysis.
Explains this association, Vulcan was discarded because it was being used for a "hypothetical planet" located between Mercury and the sun.
Although it was discovered that there arises, says the IAU, the term "vulcanoide" continues associated with any asteroid that is in the orbit of Mercury, so that the name of Vulcan could not be accepted for a moon of Pluto.
The third most popular name, Styx, also meet all the requirements, and it is the river of the underworld in Greek mythology.
The IAU working group also agreed to change by the Greek Kerberos Cerberus to avoid confusion with an asteroid called 1865 Cerberus.