Feeds

Hubble detects new Plutonian moon

Small fourth companion for faraway icy dwarf-world

Security for virtualized datacentres

A Hubble Space Telescope search for possible rings around Pluto has turned up a diminutive fourth moon orbiting the dwarf planet.

Pluto's moon P4 seen in grainy Hubble image. Pic: NASA

The body, temporarily dubbed P4, joins Charon, Hydra and Nix in the family circling the icy world. NASA says P4 is around 8 to 21 miles (13 to 34 km) in diameter, as compared to Hydra and Nix's 20 to 70 miles (32 to 113 km) and big brother Charon's 648 miles (1,043 km).

Graphic of Pluto's moons in their relative orbits. Pic: NASAP4's orbit lies between those of Hydra and Nix, which Hubble also first spotted back in 2005.

Mark Showalter of the SETI Institute in Mountain View, California, who was in charge of this Pluto obervation programme, enthused: "I find it remarkable that Hubble's cameras enabled us to see such a tiny object so clearly from a distance of more than 3 billion miles."

NASA's New Horizons spacecraft is due to whizz past Pluto in 2015, and Hubble's work in peering at the dwarf's "ice and molasses" surface and moons will provide useful in planning the close encounter. Alan Stern, New Horizons principal investigator, said: "This is a fantastic discovery. Now that we know there's another moon in the Pluto system, we can plan close-up observations of it during our flyby."

Regarding Pluto's elusive rings, NASA notes: "Scientists believe material blasted off Pluto's moons by micrometeoroid impacts may form rings around the dwarf planet, but the Hubble photographs have not detected any so far." ®

Bootnote

NASA says of the P4 images above: "P4 was first seen in a photo taken with Hubble's Wide Field Camera 3 on June 28. It was confirmed in subsequent Hubble pictures taken on July 3 and July 18. The moon was not seen in earlier Hubble images because the exposure times were shorter. There is a chance it appeared as a very faint smudge in 2006 images, but was overlooked because it was obscured."

Internet Security Threat Report 2014

More from The Register

next story
SECRET U.S. 'SPACE WARPLANE' set to return from SPY MISSION
Robot minishuttle X-37B returns after almost 2 years in orbit
LOHAN crash lands on CNN
Overflies Die Welt en route to lively US news vid
'Utter killjoy Reg hacks have NEVER BEEN LAID', writes a fan
'Shuddit, smarty pants!' Some readers reacted badly to our last Doctor Who review ...
Experts brand LOHAN's squeaky-clean box
Phytosanitary treatment renders Vulture 2 crate fit for export
Carry On Cosmonaut: Willful Child is a poor taste Star Trek parody
Cringeworthy, crude and crass jokes abound in Steven Erikson’s sci-fi debut
White LED lies: It's great, but Nobel physics prize-winning great?
How artificial lighting could offer an artificial promise
NASA eyeballs SOLAR HEAT BOMBS, MINI-TORNADOES and NANOFLARES on Sun
Astro boffins probe fiery star's hidden depths
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Win a year’s supply of chocolate
There is no techie angle to this competition so we're not going to pretend there is, but everyone loves chocolate so who cares.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Saudi Petroleum chooses Tegile storage solution
A storage solution that addresses company growth and performance for business-critical applications of caseware archive and search along with other key operational systems.