A close-up image of a region close to Pluto’s equator has revealed a range of youthful mountains, which are rising as high as 11,000 feet (3,500 metres) above the dwarf planet’s icy surface.
It’s thought that the mountains formed no more than 100 million years ago – making them mere youngsters compared to the 4.56-billion year age of our Solar System – and there still may be processes building up, according to Geology, Geophysics and Imaging (GGI) team leader Jeff Moore. Given the terrain shown in the image above, which covers less than one percent of Pluto’s surface, it’s thought that Pluto may be geologically active today.
Moore and his colleagues estimated the youthful age based on the lack of craters at the scene. Similarly to the rest of the dwarf planet, this area would have been bombarded by space debris for billions of years, leaving the surface heavily cratered – that is, unless recent activity had given the area a facelift, erasing the indentations. “This is one of the youngest surfaces we’ve ever seen in the Solar System,” adds Moore.
Pluto cannot be heated by gravitational interactions with a much larger planetary body, like the moons of the giant planets, so there must be other processes generating the mountainous landscape. “This may cause us to rethink what powers geological activity on many other icy worlds,” says GGI’s deputy team leader John Spencer of the Southwest Research Institute in Boulder, Colorado.
Methane and nitrogen ice covers most of Pluto’s surface but the team believe that these materials are not strong enough to build mountains. A stiffer material, like water-ice, is likely to have made the peaks. “At Pluto’s temperature, water-ice behaves more like rock,” explains Bill McKinnon of Washington University, St. Louis.
The close-up of Pluto’s “young” terrain was taken around 1.5 hours before New Horizon’s closest approach to Pluto, when the craft was around 47,800 miles (77,000 kilometres) from the surface of the planet.
Check out how our view of the dwarf planet has changed in our latest video.