Pluto’s complex world revealed

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New Horizons completed its historic flyby of Pluto on July 14 scratching the dwarf planet off the list of unexplored objects in our Solar System. Though it will takes months before we receive all the data that New Horizons has collected in the 21 hours of flyby, the preliminary images sent across by the spacecraft unravel the complex world of Pluto.

From icy mountains to possible craters, Pluto is a complex dwarf planet and New Horizons is revealing details fulfilling the 9 years worth of expectations that piled up as the spacecraft was cruising towards the Kuiper Belt object.

The first ever closeup images of region near Pluto’s equator reveal a youthful mountains rising as high as 11,000 feet (3,500 meters) above the surface of the icy body. Why youthful? Because astronomers believe that the mountains would have formed no more than 100 million years ago.

Astronomers at NASA say that this particular surface is possibly the youngest of all surfaces they have seen in our solar system till date. The relatively less age of the mountains indicate that the dwarf planet could be geologically active.

Gravitational interactions with larger bodies play a major role in geological alternations on a planet or a moon; however, in case of Pluto that isn’t the case as it is not influenced by any such planetary body. Astronomers believe that there are forces at play, which are not known yet, that may have caused the formation of mountain landscape.

“This may cause us to rethink what powers geological activity on many other icy worlds,” says GGI deputy team leader John Spencer at SwRI.

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.


Pluto wasn’t the only object in space that New Horizons was going to click close-up pictures of! Charon was also relatively close and New Horizons has taken full advantage of the opportunity to view Charon in greater detail as well.

Latest images from Charon also reveal a youthful and varied terrain. Scientists are surprised by the apparent lack of craters. A swath of cliffs and troughs stretching about 600 miles (1,000 kilometers) suggests widespread fracturing of Charon’s crust, likely the result of internal geological processes. The image also shows a canyon estimated to be 4 to 6 miles (7 to 9 kilometers) deep. In Charon’s north polar region, the dark surface markings have a diffuse boundary, suggesting a thin deposit or stain on the surface.

New Horizons also observed the smaller members of the Pluto system, which includes four other moons: Nix, Hydra, Styx and Kerberos. A new sneak-peak image of Hydra is the first to reveal its apparent irregular shape and its size, estimated to be about 27 by 20 miles (43 by 33 kilometers).

The observations also indicate Hydra’s surface is probably coated with water ice. Future images will reveal more clues about the formation of this and the other moon billions of years ago. Spectroscopic data from New Horizons’ Ralph instruments reveal an abundance of methane ice, but with striking differences among regions across the frozen surface of Pluto.