Science and techno world topic: Space
Some stars may be orbited by planets diamond. This possibility opens experiments and calculations of American geoscientists. If the birth of a star cloud abundant carbon, it can be compressed deep inside of planets to diamond.
In a sample have been under high pressure and temperature dark grains of wustite (iron (II) oxide, center) and diamond (right) is formed.
Photo: Ohio State University
Especially with larger planets, this process could come to fruition, Born Under Cayman explained by the Ohio State University. "It is conceivable that there are planets with up to 15 Earth masses, half of diamond," says the researcher. Since diamond is a very good conductor of heat, but such worlds are likely to cool rapidly and therefore be extremely inhospitable.
The structure of the Earth with its iron core and its silicate rocks probably reflects reflect the composition of the gas and dust cloud that have evolved out of the sun and its planets. Born and colleagues were now under the question might look like the inside of rocky planets, which have emerged from a highly carbonaceous cloud. The researchers used this sample of iron, carbon and oxygen pressures of up to 65 gigapascals (650,000 atmospheres) and temperatures of more than 2,100 degrees Celsius, as they exist in the mantle. With the so obtained data they fed a thermochemical model planet.
Are deep inside a rocky planet is carbon, therefore, not only in oxidized form in minerals. Part of it lies rather in plain carbon, which can be transformed under the weight of several hundred kilometers of rock into diamond. In addition, a portion of the carbon reacts with iron to form iron carbide, which sank into the planet core. The oxygen reacts with the iron and thus forms the iron mineral wustite.
Analogous to the Earth could form apparently also in carbon planets core and mantle, concludes Wendy Panero, the head of the research group. "The core would be highly carbonaceous and would thus resemble steel, while the carbon-rich shell stocks in large part made of diamond." Because such a planet auskühle quickly, he as probably only temporarily to a magnetic field, plate tectonics and an atmosphere, the researcher . "We believe that a diamond planet is a very cold and dark world."
Research: Under Cayman T. Born, Wendy R. Panero and Jason E. Kabbes, School of Earth Sciences, Ohio State University, Columbus
Presentation at the 2011 Fall Meeting of the American Geophysical Union, San Francisco; # P21C-1679