The mind-blowing dwarf planet has ice mountains and water
Photograph: NASA
It has been relegated to a dwarf planet. NASA scientists expected little from their first mission to Pluto -- probably craters and nothing more.
But Pluto turned out to be full of surprises. The first batch of close-up images was released on Wednesday, a day after NASA’s New Horizons spacecraft flew past the former ninth planet. The probe travelled more than 3.6 billion miles and unravelled a whole new world.
"I'm completely surprised," said Alan Stern, principal investigator for NASA's New Horizons spacecraft.
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 above the surface of the icy body. The mountains likely formed no more than 100 million years ago, said Geology, Geophysics and Imaging team leader Jeff Moore of NASA’s Ames Research Center in Moffett Field, California.
“This is one of the youngest surfaces we’ve ever seen in the solar system,” said 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," said GGI deputy team leader John Spencer of the Southwest Research Institute in Boulder, Colorado.
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 photos released by NASA also give a new, crisp view of Pluto’s largest moon Charon. Scientists are surprised by the apparent lack of craters. The images reveal an intriguing world with a swath of cliffs and troughs stretching about 600 miles (1,000 kilometers) and a canyon 4 to 6 miles (7 to 9 kilometers) deep.
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), said NASA in a statement.
So what next?
New Horizons is now more than a million miles on the other side of Pluto. The probe will keep flying out into the Kuiper Belt. NASA may extend its mission and send it to explore another small world.
