NASA's New Horizons spacecraft finds second mountain range in Pluto's 'heart'

WASHINGTON: NASA's New Horizons spacecraft has discovered a second mountain range situated between bright, icy plains and dark, heavily-cratered terrain on the lower-left edge of Pluto's heart-shaped region.

The image was acquired by New Horizons' Long Range Reconnaissance Imager (LORRI) on July 14 from a distance of 77,000 kilometres and sent back to Earth on July 20. Features as small as one kilometre across are visible.

New Horizons mission found the new, apparently less lofty mountain range on the lower-left edge of Pluto's best known feature, the bright, heart-shaped region named Tombaugh Region.

These newly-discovered frozen peaks are estimated to be 1-1.5 kilometres high, about the same height as the Appalachian Mountains in US.

The Norgay Mountains discovered by New Horizons on July 15 more closely approximate the height of the taller Rocky Mountains.

The new range is just west of the region within Pluto's heart called Sputnik Plain. The peaks lie some 110 kilometres northwest of Norgay Montes.

This newest image further illustrates the remarkably well-defined topography along the western edge of Tombaugh Region.

"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 Centre 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," said Moore.

While Sputnik Plain is believed to be relatively young in geological terms - perhaps less than 100 million years old - the darker region probably dates back billions of years.

Moore noted that the bright, sediment-like material appears to be filling in old craters.