New Horizons captures Pluto's moon Charon in best images yet

The latest views of Pluto's biggest moon, Charon, transmitted by NASA's New Horizons spacecraft show what many scientists never expected: mountains, canyons, faults and geologic upheaval, in higher resolution than ever.

"It looks like the entire crust ofCharonhas been split open," John Spencer, a New Horizons scientist at the Southwest Research Institute in Boulder, Colo., saidin a statement accompanying the release of the new images Thursday.

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NASA scientist Ross Beyer added: "We thought the probability of seeing such interesting features on this satellite of a world at the far edge of our solar system was low. But I couldn't be more delighted with what we see."

Charon is one of five known moons of Pluto and is about half its size proportionally huge for a moon. NASA said many researchers expected Charon's surface to be bland and crater-pocked, but were surprised at the imagesNew Horizons captured in its flyby in mid-July.

The first newly released picture, above, was taken July 14, just before New Horizons made its closest approach to Charon. It shows a lunar surface with far less colour variation compared with Pluto. The main areaof contrast is a reddish-brown splotch in the northern polar area, dubbed MordorMacula, according to NASA.

To the upper left in the imagelies a series of uplands dotted by craters, underlined by a deepdiagonal system of faults and canyons running from mid-upper-right to mid-lower-left. NASA said the canyons run formore than 1,600 kilometres almost four times the length of the Grand Canyon, and in some places twice as deep.

"These faults and canyons indicate a titanic geological upheaval in Charon's past," the space agency said.

The second image, below,is a composite showing the much more colourful and radiantPluto in front and Charonbehind.Pluto, too, has a red region near its equator.

NASA said still higher resolution pictures of Charon are on their way over the next year as New Horizons transmits the contents of its data banks a slow, painstaking process because of its distance, weak radio signal and the limited number of satellite dishes on Earth that can receive its faint transmissions.

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