Styx isn’t just your favorite rock group from the ’70s, it’s also the name of Pluto’s fifth moon, discovered by the Hubble Space Telescope a decade ago! This video shows the motion of Pluto's five moons as photographed by Hubble in 2012. At the time, Styx was named “P5” before receiving a slightly creepy new moniker. All of Pluto's moons are named for mythological figures associated with the underworld. Credit: NASA, ESA, M. Showalter (SETI Institute), and L. Frattare, and G. Bacon (STScI). | Hu