The dwarf planet Pluto is much more heterogeneous than previously thought: probe “New Horizons,” the US space agency Nasa, collected images of mountains, canyons, full of craters and large landscapes and smooth ice. Pluto and its largest moon, Charon, show unexpected geological activity. So the researchers of the “New Horizons” led by Alan Stern of the Southwest Research Institute in Boulder, State of Colorado, in the first scientific summary of the comments, published today (15/10/2015) in Science .
Among other things, “New Horizons” determined accurately for the first time the size of the diameter of the planet, of 2,374 kilometers. The probe was unable to determine flattening caused by its own rotation, as in the case of Earth, making it concluded that the dwarf planet is completely spherical. In addition, the planet’s surface is characterized by ice. But “New Horizons” also photographed mountains that reach up to 3,000 meters. Ice nitrogen, carbon monoxide and methane discovered before the visit of the spacecraft to dwarf planet would be too soft to such heights.
So the researchers now believe that these types of ice are in many over a relatively thin layer on the surfaces and actually be stacked ice water, considerably stronger. The mountains of Pluto, which resemble Rocky in the US, then would icebergs. Surprisingly, in Pluto there are relatively few impact craters result, if we consider the bombardment of cosmic bodies that is assumed in the place where the planet is located, the Kuiper belt. Astronomers believe that craters could have disappeared due to active geological processes.
This could mean, for example, the frozen plain Sputnik, which has not a single crater could be about 100,000 years old very young in terms of age of the Solar System, which has 4,500 million years. It is also unclear what energy sources drive the geological activity. In the icy plains probe he found evidence of a type of glacier, where the ice appears to be moving or still keep flowing. The images show how the ice sheets bordering the obstacles they encounter.
Varied range of colors
Another aspect that surprised the researchers was the diversity of colors on the planet: with frozen surfaces pure white, red and slightly bluish discovered landscapes. The reddish apparently originate connections called Tholins carbon, formed in Pluto when fast cosmic particles mixture of nitrogen and methane are bombarded with UV radiation. In low concentrations provide a range of colors ranging from yellow to dark red
Another discovery. Pluto’s atmosphere is thinner than previously thought. The atmospheric pressure at the surface is about 10 million bars, one hundred thousandth part of the Earth. What is not clear is whether the atmosphere has been recently reduced. In the atmosphere of Pluto, “New Horizons” also photographed a veil of mist whose origin is unclear. The moon Charon with a diameter of 1,212 kilometers, also offers surprisingly different landscapes. Among others, has a system of gigantic canyons and kilometers deep that at least four multiply the length of the Grand Canyon on Earth.
The guns across the surface of Charon and many researchers speculate that possibly ago long it freezes there an underground ocean that would have blown all bark. Charon appears geologically similar to Pluto, but also in this case the energy source of the geologic activity is clear.
“New Horizons” also investigated moons Nix and Hydra. According to the results, Hydra has dimensions of 40 x 30 x 50 kilometers and 30 kilometers Nix and both have a surprisingly strong reflective capacity. Astronomers believe that Nix and Hydra are covered with ice. What remains a mystery is how the satellites of Pluto may have preserved their pristine surfaces so for billions of years, given the numerous environmental incidents in the Kuiper Belt.
MS (dpa / AFP)
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