Name Pluto's Moons!

Two of Pluto's moons have no names, but that's about to change. Planetary astronomer Mark Showalter announces a contest where you can help name the newest discoveries.

Update (Feb. 25, 2013): Two clear winners stand out from the 450,234 votes collected: Vulcan and Cerberus. But the names aren't final yet. The formal approval process could take 1-2 months. Stay tuned.

In 2011 and 2012, Hubble observations revealed two new moons orbiting Pluto, bringing the total number in Pluto's surprisingly complex system up to five. Scientists have been referring to the moons as P4 and P5, but they need proper names and that's where you come in. Mark Showalter of the P4/P5 discovery team announces a contest where, starting today, you can help decide what we'll call Pluto's newest moons. Naming a moon is a rare privilege for any astronomer. Fewer than 200 moons have been discovered orbiting the Solar System's planets (dwarf or otherwise).

Over the centuries, the astronomical community has established standards for the naming of moons. Most names come from ancient mythologies. The moons of Uranus are the exception, with names coming primarily from the works of William Shakespeare.

These rules ensure that newly discovered moons receive names that have already stood the test of time. The same names will still be in use centuries and even millennia from now. Whereas today's literature might be long forgotten, we can be confident that future generations of astronomers (and maybe even astronauts) will still recall the stories from Mount Olympus and Stratford-upon-Avon.

I suspect these naming traditions did not arise by accident. For whatever reason, we humans seem to have a deep-seated, pre-scientific need to interpret the night sky in terms of stories. Naturally, we choose the big stories, involving grand themes, great powers and deep mysteries.

I've been involved in naming three moons: Pan at Saturn, plus Mab and Cupid at Uranus. In each case, the process was simple and straightforward. We pulled out our dusty old copies of Bullfinch's Mythology or the Riverside Shakespeare and started browsing. (In each case, I also experienced a wistful regret that I had not spent more time studying literature in college, back when I still had the opportunity.)

When we announced the discoveries of Pluto's fourth and fifth moons, it became clear to me that the naming process might have to be different. This time, I received hundreds of spontaneous, unsolicited suggestions. I suspect that some of the world's affection for Pluto comes from its so-called "demotion" to dwarf planet status. Perhaps it is also because the names of Pluto's moons are all associated with Hades and the Underworld, the stuff of so many of our most primal fears. Whatever the reason, the discovery team has decided that it would be unfair to keep the naming process to ourselves.

Starting today, we are trying something new. We are asking the public to help us name the moons. Visit plutorocks.seti.org and tell us what you think. We have seeded the ballot with a few names, or you can propose your own. The names will still have to be approved by the International Astronomical Union, but we will use your votes to help us decide the names we propose.

Please join us in adding the next chapter to the story of Pluto.

Mark Showalter is a senior research scientist at the SETI Institute in Mountain View, California. Most of his research focuses on the planetary rings and small moons of the outer planets.