Latest Pluto data shows Earth-like glaciers, rapidly thinning atmosphere

Read more: http://www.smh.com.au/technology/sci-tech/latest-pluto-data-shows-earthlike-glaciers-rapidly-thinning-atmosphere-20150724-gik9nn.html#ixzz3hmNQfc2g

The atmosphere of Pluto backlit by the sun when the New Horizons spacecraft was about 2 million kilometres away. The image, delivered to Earth on July 23, is displayed with north at the top of the frame. Photo: NASA/AP

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Baltimore: Pluto's "heart" contains shifting glaciers of frozen nitrogen, methane and carbon monoxide, and its atmosphere is both deeper and disappearing more rapidly than scientists predicted.

Close-up images of Tombaugh Regio, the large heart-shaped formation near Pluto's equator, show the smooth, brightly coloured area flowing around mountains and filling craters. The geology appears just like glaciers on Earth, New Horizons mission leaders said.
A new combination of images captured by the New Horizons spacecraft with enhanced colours to show differences in the composition and texture of Pluto's surface. The images were taken when the spacecraft was 450,000 kilometres away. Photo: NASA/AP

Observations of Pluto's atmosphere meanwhile show a haze extending 160 kilometres above the surface, further than they expected. And air pressure on the surface, a tiny fraction of air pressure on Earth, is dropping dramatically as the dwarf planet moves into the cold, further from the sun in its elliptical orbit. The revelations are some of the first to come from New Horizons' historic encounter with Pluto on July 14, a mission managed by the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.

Most of the data gathered during the fly-by is still on the spacecraft, but with about 5 per cent of it on the ground, it is already proving illuminating, the scientists said.

"It's really turning out to be just a scientific wonderland," said Alan Stern, the mission's principal investigator and a researcher at the Southwest Research Institute in Boulder, Colorado.

The scientists believe that heat from within Pluto may be driving some of the motion of the ice that covers the western half of Tombaugh Regio, causing it to rise and fall beneath the surface. Even at Pluto's surface temperatures of about 380 degrees below zero, the elements prevalent in the ice are relatively soft and malleable, said Bill McKinnon, deputy leader of the mission's geology team. The dwarf planet is so cold, scientists suspect that much of its atmosphere is frozen to its surface. New Horizons data show its atmosphere's mass has dropped significantly relative to estimates from two years ago, probably because Pluto is moving away from the sun in its 248-year orbit. Air pressure on its surface is 1/100 thousandth that of the pressure on the surface of Earth, they said.

The Baltimore Sun

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The world’s biggest hydropower project may be causing giant landslides in China
A giant landslide near China’s Three Gorges Dam last night sent six meter waves crashing down on a fleet of fishing boats, leaving five people injured, and killing one. Dozens of residents near the Daning River, where the landslide took place, have been evacuated. The incident is only the latest natural disaster that critics believe the $59 billion mega-dam has caused, twelve years after it was built on the Yangtze River to provide hydropower to China. The world’s largest hydroelectricity operation, an engineering feat and point of national pride, is also another reminder of the risks Chinese policymakers take when it comes to huge infrastructure projects. Chinese scientists and other experts have long warned that the 600-kilometer-deep reservoir created by the dam increases pressure on the surrounding land, in a region already prone to landslides and earthquakes. After a series of landslides throughout the 2000s, China’s ministry of land resources finally admitted in 2012 that there had been “70% more landslides and bank collapses in the area than had been predicted.”Officials said then they would not be able to prevent geological accidents caused by the dam over the next three to five years and that 100,000 residents, in addition to the 1.3 million that were initially moved, would have to be relocated. Last year, a landslide on the Yangtze wiped out one of the Three Gorges hydropower stations. China is still installing more dams and hydropower operations as part of a campaign to wean itself from fossil fuels—by the end of last year, installed hydroelectricity capacity was over 300 million kilowatts, accounting for about 20% of China’s electricity and almost a quarter of the world’s total hydropower. But progress is moving more slowly now. China’s goal, to raise capacity to 420 million kilowatts by 2020, has been hampered by a slower approval process, perhaps because of incidents like this week’s land slide.

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