New Horizon Spacecraft Exploration to PlutoExploration has been the hallmark of the West.
New close-up images of a region near Pluto’s equator reveal a giant surprise: a range of youthful mountains rising as high as 11,000 feet (3,500 meters) above the surface of the icy body.
The mountains likely formed no more than 100 million years ago -- mere youngsters relative to the 4.56-billion-year age of the solar system -- and may still be in the process of building, says Geology, Geophysics and Imaging (GGI) team leader Jeff Moore of NASA’s Ames Research Center in Moffett Field, California.. That suggests the close-up region, which covers less than one percent of Pluto’s surface, may still be geologically active today.
Moore and his colleagues base the youthful age estimate on the lack of craters in this scene. Like the rest of Pluto, this region would presumably have been pummeled by space debris for billions of years and would have once been heavily cratered -- unless recent activity had given the region a facelift, erasing those pockmarks.
“This is one of the youngest surfaces we’ve ever seen in the solar system,” says Moore.
Unlike the icy moons of giant planets, Pluto cannot be heated by gravitational interactions with a much larger planetary body. Some other process must be generating the mountainous landscape.
“This may cause us to rethink what powers geological activity on many other icy worlds,” says GGI deputy team leader John Spencer of the Southwest Research Institute in Boulder, Colo.
The mountains are probably composed of Pluto’s water-ice “bedrock.”
Although methane and nitrogen ice covers much of the surface of Pluto, these materials are not strong enough to build the mountains. Instead, a stiffer material, most likely water-ice, created the peaks. “At Pluto’s temperatures, water-ice behaves more like rock,” said deputy GGI lead Bill McKinnon of Washington University, St. Louis.
The close-up image was taken about 1.5 hours before New Horizons closest approach to Pluto, when the craft was 47,800 miles (77,000 kilometers) from the surface of the planet. The image easily resolves structures smaller than a mile across. [Article from Nasa.gov]
And more here:
On July 14 at approximately 8 a.m. Eastern time, a half-ton NASA spacecraft that has been racing across the solar system for nine and a half years will finally catch up with tiny Pluto, at three billion miles from the Sun the most distant object that anyone or anything from Earth has ever visited. Invisible to the naked eye, Pluto wasn’t even discovered until 1930, and has been regarded as our solar system’s oddball ever since, completely different from the rocky planets close to the Sun, Earth included, and equally unlike the outer gas giants. This quirky and mysterious little world will swing into dramatic view as the New Horizons spacecraft makes its closest approach, just 6,000 miles away, and onboard cameras snap thousands of photographs. Other instruments will gauge Pluto’s topography, surface and atmospheric chemistry, temperature, magnetic field and more. New Horizons will also take a hard look at Pluto’s five known moons, including Charon, the largest. It might even find other moons, and maybe a ring or two. [The restof the article is here at Smithsonian.com]
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