As if space lava lamp, a huge part of Pluto’s icy surface is constantly updated via convection. Its essence lies in the fact that the old surface of the ice is gradually being replaced by more fresh.
New Horizons mission team has combined computer models, topographical and compositional data from a spacecraft NASA last summer. Because of this they were able to determine the thickness of the layer of solid nitrogen ice, constituting most of the original “heart” of Pluto. This structure is clearly visible in the images of the dwarf planet and is a plain, plain informally called Sputnik. In addition, the scientists were able to find out the rate of change of the ice layer.
Scientists mission to use advanced computer simulations to show that the surface of the plain is covered with ice, convection “cells”, and there is a surface of less than one million years.
The findings provide additional insight into the unusual and very active geology of Pluto and possibly other space objects on the outskirts of the solar system.
“for the first time we have determined that these strange marks on the ice surface of Pluto , – says the author of the study from the Washington University in St. Louis and a member of the mission, William McKinnon (William B. McKinnon) -. We found evidence that even in the distant cold planet, located billions of kilometers from Earth, there is enough energy to geological activity “.
MacKinnon and his colleagues believe that the patterns of these” cells “,” patchwork “of them, are the result of a slow thermal convection of nitrogen ice that fill the plains of Sputnik.
Here scientists describe how the processes in the “pond”, which is likely to reach some places the depth of several kilometers. Date of nitrogen at the bottom is heated by internal heat humble Pluto, so it becomes buoyant and rises in the form of large clusters – as a lava lamp. On the surface it cools and again descends to renew the cycle.
“Plain Sputnik is one of the most amazing geological discoveries in recent years the study of the planets and the discovery by scientists vast area, more than Texas and Oklahoma combined, created process ice convection – and at the most spectacular event in this mission “, -. said Alan Stern (Alan Stern), principal investigator of the mission of the Southwest research Institute
Moving the convective surface is on average only a few centimeters per year – about the same “fast” growing the nails on the human body. Thus, the “cell” completely transform the surface of every 500 thousand years or so. This, of course, slow by human standards, but very fast relative geological time scales.
” This activity probably helps to maintain the atmosphere of Pluto’s surface due to the constant renewal of “heart”, – says McKinnon -. Do not be surprised if we find a similar process in other dwarf planets in the zone Kuiper. I hope we get a chance in future missions “.
Recall that July 14, 2015 New Horizons space probe came at the minimum distance to the dwarf planet Pluto. Since the launch of the device has been almost nine years, and the “New Horizons” had to overcome almost six billion kilometers before the rendezvous.
New Horizons Unit conducted measurements and pictures of the illuminated side of Pluto and its moon Charon, being away 12500 kilometers away from the dwarf planet.
The results of the new study are available in the scientific journal Nature.
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