Hubble Spots a Fifth Moon Orbiting Pluto

A team of astronomers using NASA's Hubble Space Telescope have made strange discovery. They have discovered another moon orbiting the icy dwarf planet Pluto.

The newly detected moon mostly known as P5 that is uneven in shape is estimated to be having 6 to 15 miles diameter. It is present in a 58,000 mile diameter circular orbit around Pluto that is assumed to be co planar with the other satellites in the system.

The team that was led by Mark Showalter, a senior research scientist at the institute, said, "The moons form a series of neatly nested orbits, a bit like Russian dolls."

The team that Showalter heads are ardently hunting for evidence that Pluto may be circled by a ring of ice particles. A $700 million NASA spacecraft named New Horizons is expected to fly into Pluto's realm in three years, and if it collides with even a single bit of ice - or with any of the planet's moons - when it flies past Pluto on July 14, 2015, it could rapidly be smashed. So the Showalter team's search, in effect, is a protective quest.

This new discovery increases the number of the known moons orbiting Pluto to five.

The team is intrigued that such a small planet can have a complex collection of satellites. P5 also provides the researchers with additional information about the formation of the Pluto system and how it evolved.  A leading theory for the moons is that they are relics of a collision between Pluto and another large cosmic object billions of years ago.

Harold Weaver of Johns Hopkins University in Baltimore said, "The discovery of so many small moons indirectly tells us that there must be lots of small particles lurking unseen in the Pluto system,"

It was in the year 1978 Pluto's largest moon Charon was discovered and in 2006 Hubble's observations uncovered two additional small moons, Nix and Hydra. In 2011 another moon P4 was found.

Provisionally named S/2012 (134340) 1, or P5, the latest moon was detected in nine separate sets of images taken by Hubble's Wide Field Camera 3 taken during June and July.

In the future the astronomers plan on experimenting with the infrared vision of Hubble's planned successor, NASA's James Webb Space Telescope for follow up observations. This telescope makes it easy to measure the surface chemistry of Pluto, its moons and many other bodies that lie in the distant Kuiper Belt along with Pluto.

Alan Stern of the Southwest Research Institute in Boulder, Colo., who is the New Horizons project's principal investigator, said "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."