Massive landslides once occurred on Pluto, forcing enormous masses of ice and rock to shift their position by many kilometers. Scientists recently came to this conclusion after studying images of the icy dwarf planet.
Landslides
A paper was recently published in the journal Icarus in which a group of scientists reported the discovery of characteristic terrain features on the dwarf planet Pluto, indicating that large-scale landslides once occurred there. This was reported by phys.org.
Landslides are well known to us from Earthly conditions. Here, they are most often associated with the presence of loose soil, which in most cases has a sedimentary origin. On most bodies of the Solar System, because there is no atmosphere, hydrosphere, or biosphere in contact with the solid surface, the ground looks completely different. The exceptions are perhaps Mars, Venus, and Saturn’s moon Titan.
Nevertheless, landslides have repeatedly been found on other planets and bodies of the Solar System. Their traces have even been found on the dwarf planet Ceres in the main asteroid belt. However, it was previously difficult to imagine them on icy Pluto.
What was seen in the photos of Pluto
To understand why landslides on Pluto are such a sensation, one must understand what the ground on this dwarf planet is made of. It consists almost entirely of several different types of ice. Here, not only water but also carbon dioxide and nitrogen exist in solid form, with rocks frozen into them.
It would seem that all this should have remained in eternal rest since the birth of the Solar System, but that is not the case. Scientists analyzed images of the surface taken by the New Horizons spacecraft back in 2015, since, after all, researchers still have no other images available. In them, they found characteristic signs of landslides: crescent-shaped traces at the tops of crater walls, giant displaced blocks of ice, and long deposits of debris on crater floors. The most interesting thing was that the fragments traveled extremely long distances compared to the height of the fall. On Earth, such mobility is often explained by the presence of liquid water, which reduces friction. On Pluto, there is no liquid water on the surface, so scientists suggest that the matter is in the extremely weak gravity (about 6% of Earth’s) and the mechanical properties of the surface ice
In total, six such areas were identified. And they are indeed large. In these areas, the ground subsided by 1.5 to 2.2 km and shifted sideways by 14.5 km. The largest of them covers about 130 km². The researchers say that in the future they will still need to study other images, and it is quite possible that they will find other similar traces there.Pluto has long been thought to be a geologically active world, with glaciers, nitrogen plains, and possibly cryovolcanism. But until now, there has been no reliable evidence of major landslides. Now it is safe to say that its surface is being renewed, albeit very slowly.
