The moon’s shape is irregular and is 6 to 15 miles across. It is in a 58,000-mile-diameter circular orbit around Pluto. It is provisionally designated as S/2012 (134340) 1. The number of known moons orbiting Pluto is now five.
The favored theory is that all the moons are relics of a collision between Pluto and another large object of the Kuiper belt billions years ago.
The new detection will help scientists navigate NASA’s New Horizons spacecraft through the Pluto system in 2015, when it makes an historic and long-awaited high-speed flyby of the distant world..
“The inventory of the Pluto system we’re taking now with Hubble will help the New Horizons team design a safer trajectory for the spacecraft,” added Alan Stern of the Southwest Research Institute in Boulder, Colo., the mission’s principal investigator.
Pluto’s largest moon, Charon, was discovered in 1978 and observations in 2006 uncovered two additional moons of small size, Nix and Hydra. In 2011 another moon, with name P4, was found in Hubble data.
In next years the New Horizons Pluto flyby, astronomers plan to use the infrared vision of NASA’s James Webb Space Telescope, for follow-up observations.