PLUTO RANGE
This image was acquired by New Horizons' Long Range Reconnaissance Imager (LORRI) during the Pluto flyby on 14 July 2015 from a distance of 48,000 miles and sent back to Earth on 20 July NASA/JHUAPL/SWRI

Images captured by Nasa's New Horizon space probe reveal yet another mountain range in the south-western part of the Tombaugh region on Pluto, popularly known as the dwarf planet's 'heart'.

The new range is situated between the bright, icy plains and dark, heavily-cratered terrain.

At a height of 1-1.5km (similar to the Appalachians) this range is shorter than the earlier one, Norgay Montes, standing tall at 3.5km straddling the lower part of the region.

The new range is just west of the region within Pluto's heart called Sputnik Planum (Sputnik Plain) showing smooth, icy plains.

"There is a pronounced difference in texture between the younger, frozen plains to the east and the dark, heavily-cratered terrain to the west," said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team (GGI) at Nasa's Ames Research Center in Moffett Field, California. "There's a complex interaction going on between the bright and the dark materials that we're still trying to understand."

The darker region probably dates back billions of years. The Sputnik Planum and Norgay Montes ranges are comparatively younger at a 100 million years.

This image was acquired by New Horizons' Long Range Reconnaissance Imager (LORRI) during the Pluto flyby on 14 July 2015 from a distance of 48,000 miles (77,000km) and sent back to Earth on 20 July. Features as small as a half-mile (1km) across are visible.

The £450m ($700m) New Horizons mission launched in January 2006 has covered around 5 billion km from Earth. It is the only probe to have approached Pluto.