Help name Pluto’s moons

CAPE CANAVERAL, Fla.—Want to name Pluto’s two tiniest moons? Then you’ll need to dig deep into mythology.
Astronomers announced a contest yesterday to name the two itty-bitty moons of Pluto discovered over the past two years.

Pluto is the Roman equivalent of the Greek’s Hades, lord of the underworld, and its three bigger moons have related mythological names: Charon, the ferryman of Hades, Nix for the night goddess, and the multi-headed monster Hydra.
The two unnamed moons—up to 32 km across—need similarly-shady references. Right now, they go by the bland titles of P4 and P5.
Online voting will last two weeks, ending Feb. 25. Twelve choices are available at www.plutorocks.com
Among the choices: Hercules, the hero who slew Hydra, Obol, the coin put in the mouths of the dead as payment to Charon, Cerebrus, the three-headed dog guarding the gates of the underworld, Orpheus, the musician and poet who used his talents to get his wife, Eurydice, out of the underworld only to lose her by looking back, and Styx, the river to the underworld.
As of yesterday afternoon, Styx and Cerebrus were leading. The vote tally is updated hourly.
“The Greeks were great story-tellers, and they have given us a colourful cast of characters to work with,” said Mark Showalter, senior research scientist at SETI Institute’s Carl Sagan Center in Mountain View, Calif.
He and other astronomers who discovered the two mini-moons using the Hubble Space Telescope, will make the winning selections.
Write-in name suggestions are welcomed, but they need to come from Greek or Roman mythology and deal with the underworld.
The winning moon names will need final approval by the International Astronomical Union.