We are the Borg.
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NASA’s New Horizons spacecraft, which flew by Pluto in July of 2015, woke up today from hibernation mode in preparation for its next rendezvous with a space rock at the edge of the Solar System. The vehicle came out of its slumber 3.7 billion miles from Earth, as it’s speeding toward an icy body nicknamed Ultima Thule that orbits the Sun way beyond Neptune. Now that the spacecraft is awake, the mission team has a very full schedule through 2018: the flyby will take place on January 1st, 2019.
"An artistic rendering of Ultima Thule, based on measurements taken by the New Horizons team Image: NASA"
It's just a large lumpy rock, about 20 miles in diameter. Still, cool! Anything else is just gravy anyway. It already accomplished what it was supposed to.
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Scientists reveal the secrets behind Pluto’s dunes
Following spatial analysis of the dunes and nearby wind streaks on the planet’s surface, as well as spectral and numerical modelling, scientists believe that sublimation (which converts solid nitrogen directly into a gas) results in sand-sized grains of methane being released into the environment.
These are then transported by Pluto’s moderate winds (which can reach between 30 and 40 kmh), with the border of the ice plain and mountain range providing the perfect location for such regular surface formations to appear.
The scientists also believe the undisturbed morphology of the dunes and their relationship with the underlying glacial ice suggests the features are likely to have been formed within the last 500,000 years, and possibly much more recently.
Dr Eric Parteli, Lecturer in Computational Geosciences at the University of Cologne, said:“On Earth, you need a certain strength of wind to release sand particles into the air, but winds that are 20% weaker are then sufficient to maintain transport. The considerably lower gravity of Pluto, and the extremely low atmospheric pressure, means the winds needed to maintain sediment transport can be 50 times lower. The temperature gradients in the granular ice layer, caused by solar radiation, also play an important role in the onset of the saltation process. Put together, we have found that these combined processes can form dunes under normal, everyday wind conditions on Pluto.”