Back on June 21, 2006 the International Astronomical Union announced that the two recently discovered moons swinging around Pluto have now been officially named. One is to be called Nix, and the other is to be called Hydra. They join Charon, Pluto’s largest moon, discovered back in 1978. They were discovered by astronomers using the Hubble Space Telescope.
In addition to having some mythological relation to Pluto, the names Nix and Hydra were chosen because their first initials, “N” and “H,” are also the first letters of New Horizons, the NASA spacecraft launched in January 2006 towards the Pluto system. Currently past Neptune and on its way for a rendezvous with Pluto in 2015, the New Horizons spacecraft will make a point of visiting them. The “P” and the “L” in Pluto are similarly significant. The name Pluto was chosen for the ninth planet because it honored the astronomer Percival Lowell, who instigated the search that ultimately resulted in the discovery of Pluto.
Pluto is the Greek God of the underworld, and the new names for these moons are in keeping with who he is. In Greek mythology, Nyx was the goddess of the night and the mother of Charon, the boatsman who ferried souls across the River Styx into the underworld ruled by Pluto. Hydra was a giant, nine-headed monster, the second of the Twelve Labors of Hercules. Slaying Hydra was not easy for Hercules. Every time he chopped off one of the creature’s heads, two quickly sprouted in its place. He finally managed to finish the beast off by calling on his nephew Iolaus for help. Iolaus came up with the idea of using a burning firebrand to cauterize the neck stumps after decapitation. So, as Heracles cut off each head, Iolaus burned the open stump. After much cutting and burning, the hydra was finally terminated.
When I went to Encyclopedia Britannica online to do research on the names—I was not certain about Nix—all I found was an article about the Germanic sprite called Nix. In Germanic mythology, Nix is a water being that is half human, half fish. It lives in a beautiful underwater palace and mingles with humans by assuming a variety of physical forms, usually female. When I read all that, I was puzzled why that would have been chosen for the moon’s name.
But then I went to Wikipedia, which has been criticized by some as inaccurate given its open source nature. Open source means that the articles can be rewritten by anyone who visits the website. But it was at Wikipedia that I found not only information about the mythology, but within hours of the announcement that the moons had names, there was already a nice article about the moon.
Wikipedia made it easier for a casual searcher to learn the fact that Nyx was the Greek goddess of night and thus more likely the source of the name for the moon than the Germanic sprite, given that Hydra and Charon, are associated with Greek myth, not Germanic, and the naming convention for the planets and moons of our solar system requires Greek or Roman names.
The spelling of the German water sprite is with an “i” and of the Greek goddess with a “y.” The International Astronomical Union changed the spelling of the moon to “Nix,” following the Egyptian spelling of the goddess. They did this to avoid confusion with two asteroids that had already been named “Nyx.”
I later discovered that the online version of Encyclopedia Britannica does have an article on the Greek goddess. But one can find it only if one spells the name “Nyx” rather than “Nix.” Wikipedia, by contrast, gives the searcher both articles, regardless of how one has spelled the name in his or her search. It also gives a hyperlink from one to the other.
Frankly, I find Wikipedia very handy most of the time. On controversial topics, especially anything having to do with modern politicians, there is a tendency for their articles to be very biased, inaccurate, and often defaced by those who dislike the given politician. But articles on general topics I’ve found tend to be quite well done. And the editors of Wikipedia work tirelessly to try to correct and fix any errors that do show up. Additionally, I’ve found that Wikipedia is very quick about keeping articles up to date—somewhat faster than Britannica.
But I still like Britannica, and in general, its articles are more detailed and more thorough. I purchased the book form of the Encyclopedia Britannica shortly after I got married back in the early 1980s. It’s now obviously become a bit out of date, but I’m not planning on replacing it. Instead, I pay for Britannica’s online version, which has all the text of the printed encyclopedia, but is much quicker and easier to use, and is kept constantly up to date. I recommend to my students that they simply subscribe to the online version, rather than purchasing the dead tree version. I also have a version of Britannica that I keep on my , for those times when I need to research something but don’t have access to the web. Wikipedia, of course, has the advantage of being absolutely free. Using multiple sources when doing even initial research is usually a good idea, and encyclopedias are always a good place to start.