Vulcan and Cerberus win online poll to name Pluto’s smallest moons

The people have spoken, and they would like the two smallest moons of Pluto to be named Vulcan and Cerberus.

When scientists at the SETI Institute stopped accepting new votes on the Pluto Rocks website at 9 a.m. Pacific time Monday, Vulcan was the only candidate with more than 100,000 votes. In fact, it blew away the rest of the field with 174,062 votes from people all over the world.

The biggest fan of the name has got to be William Shatner, who suggested it in a tweet on Feb. 12.

“So what do you think of the idea of naming the two moons of Pluto Vulcan and Romulus?” he asked of his 1.35 million followers. One day later, he tweeted this update: “Did you hear? They added the name Vulcan to the list of possible names for Pluto’s moons! You did it! I’m so happy.” Then he exhorted his followers to vote for Vulcan more than a dozen times with tweets such as this: “It’s a new day- at least here in Los Angeles- have you voted for Vulcan?”

On Monday morning, he shared the news: “174,062 votes and Vulcan came out on top of the voting for the naming of Pluto’s moons. Thank you to all who voted!”

Vulcan, of course, is the home planet of the Vulcans of Star Trek fame. Spock, who served along with Captain James T. Kirk (played by Shatner), has Vulcan heritage. Romulus is the home planet of the Romulans, the antagonistic beings who are related to Vulcans but have the opposite temperament.

At first, election organizer Mark Showalter, a planetary astronomer with SETI’s Carl Sagan Center for the Study of Life in the Universe, doubted that either name was worthy of serious consideration for P4 and P5, the temporary names for Pluto’s fourth and fifth moons. After all, there are rules, he explained on the election website Pluto Rocks: “By tradition, the names of Pluto’s moons come from Greek and Roman mythology, and are related to the ancient tales about Hades and the Underworld.”

Romulus was a non-starter because it has already been used to name one of the moons of the asteroid Sylvia. (The other moon is called Remus.)

Vulcan was a little more complicated. It’s the name of the Roman god of fire, so it satisfies the mythology requirement. But it’s also the name of a nonexistent planet that was once thought to orbit the Sun even closer than Mercury.

“Some of the world’s greatest astronomers spent quite a long time looking for it and they never saw it because it isn’t there,” Showalter explained in a Google+ hangout. “Some people say, ‘No, we should save the name Vulcan for some place that’s big and hot.’ I guess one response to that would be, ‘Well, we found all the places [in the solar system] that are big and hot and they’ve all got names now.’”

So Vulcan was added to the ballot and it blew away the competition.

The second-place finisher with 99,432 votes was Cerberus, the Roman name for the three-headed dog that guards the entrance to the underworld. Although this was one of the official nominees from SETI, it turned out to be a little tricky too. The solar system is already home to an asteroid by that name, Showalter noted. One potential solution would be to change the spelling to Kerberos, as the creature is known in Greek mythology, he said.

Rounding out the top five were Styx (87,858 votes), Persephone (68,969 votes) and Orpheus (51,197 votes).

More than 450,000 total votes were cast (some people may have voted more than once), with about half of those coming from the United States. The ballot was available in more than a dozen languages, including Russian, Chinese, Korean, Japanese, Arabic and Farsi. “Almost every country on the planet has had at least a couple of votes come in,” Showalter said.

The final decision will be made by the nomenclature working group of the International Astronomical Union. Showalter is a member of that committee, but he pledged to recuse himself from the deliberations when the permanent names for P4 and P5 are considered a few months from now.

You can watch Showalter’s hangout online here.

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