Astronomers say the Hubble Space Telescope has discovered a new, fifth moon orbiting the icy dwarf planet Pluto.
Pluto’s new moon, dubbed P5 until it gets a proper name, is estimated to be irregular in shape and 6 to 15 miles across. P5 joins Charon, Hydra, Nix and P4 in orbit around the icy planet.
Charon, Pluto’s largest moon at 650-mile-wide, was discovered in 1978. Its two smaller moons, Nix and Hydra, were found in 2005.
“The moons form a series of neatly nested orbits, a bit like Russian dolls,” astronomer Mark Showalter of the SETI Institute in Mountain View, Calif., said in a NASA release Wednesday.
According to the Scientific American, P5 was found in the course of checking out the potential collision hazards facing NASA’s New Horizons spacecraft for the Bastille Day flyby on July 14, 2015.
NASA says the discovery will help the New Horizons spacecraft navigate its way to the planet.
“Moving past the dwarf planet at a speed of 30,000 miles per hour, New Horizons could be destroyed in a collision with even a BB-shot-size piece of orbital debris,” NASA said in a press release.
Mark Showalter of the Seti Institute said names for the latest new moon, and last year’s discovery, will not be proposed until the team finishes analysing the Hubble data – in case there are more hidden moons.
In the meantime, the Christian Science Monitor shares the interesting background behind the naming of the icy dwarf planet and its other moons:
Pluto was the god of the underworld in Roman mythology. Charon, is named after the mythical ferryman who carried the souls of the newly deceased across the River Styx, which separated the world of the living from that of the dead. Nix, Pluto’s second-closest moon, was the Greek goddess of darkness and night, and Charon’s mother. Hydra, the third closest to Pluto, was a many-headed serpent that guarded a back entrance to the underworld located deep below the surface of a lake.
Keeping in line with the already established naming scheme (mythological characters of the underworld), what do you think the name for Pluto’s new moon should be?