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It is believed that all the planetary systems are formed of two components - of chondrules and calcium-aluminum inclusions (CAW). For a long time scientists thought that both of these components were formed at different times: first appeared KAV, but after a few million years appeared and Hendry. But recent studies have shown that most likely they were born at the same time.
In planetology it is believed that the emergence of a system of planets and satellites, as well as the hierarchy of small bodies in the Solar system preceded the creation of the basic raw materials for generation of solid bodies, with the exception of the planets of the other type, gas and ice giants. In the Solar system, select "construction materials" extremely limited is only two types: Hendry and calcium-aluminum inclusion (CAW).
The fact that only these two components responsible for "hardening" matter in the Solar system. Of these, one of these "pervoocherednikov" grew up and was enlarged space rocks that are experienced, forming planetesimals - prototypes future planets. Blocks in the protoplanetary disk, laying the Foundation for the birth of planetesimals, "programmed" and all future protoplanetary upheavals that accompanied the formation of all large bodies, of which, after clashes completely formed the planets in their diversity. But when and how lay these two types "pervoocherednikov" great construction project of the planets in the Solar system?
A new concept of the initial epoch of appearance of solid precursor space rocks, which formed the planets, their satellites and many asteroids - turned out to be easier than previously thought. It is logical to assume that because two components, they can occur at different times. Such a view has been proposed before, but today, there are strong arguments in favor of simultaneous formation of two main components-pervoocherednikov, and it radically changes the picture of formation of the firmament in the Solar system.
Recall that our Sun was born approximately 4.6 billion years ago, it was surrounded by a cloud of gas and dust. What was the first solid material from which created the first blocks? This writes Elizabeth Howell (Elizabeth Howell) on the basis of the work of researchers from the University of Copenhagen James Connelly (James Connelly) with co-authors, which outlines a new paradigm: both solid component arose at the same time.
All researchers reasonably believed that the CAW and Hendry originated billions of years ago at compression of the protoplanetary cloud of gas and dust. Both of these solid particles found in meteorites, which are parts of the cosmic stone rocks, which, as a rule, billions of years. Debris fell to the Ground, find scientists and Amateurs. Subsequently, this space rockfall is the object of thorough research.
Previously, researchers believed that the emergence of two well-known types of solid particles separated in time by several million years. But a new technique Dating refutes this position. Simultaneous formation of chondrules and KAV opens a new page in the understanding of the early solar system. It is reported by a group of researchers headed Connelly in the work, published in the second issue of the journal Science.
The origins of the two types is that KAV are formed from stiffening gas droplets of condensate at a temperature higher than 1880 degrees Fahrenheit (1030 degrees Celsius, or 1300 degrees Kelvin). They are not similar Hendry - captured dust particles, which are melting fast and cool, solidify at the lower temperature is below 1340 degrees Fahrenheit (727 degrees Celsius or 1000).
Previously it was thought that first appeared KAV, and only a few tens of millions of years, when the temperature was considerably decreased - Hendry. If the first harden even at a temperature of 1300 To the second condense below 1000 K. it is Very important that one KAV, but without chondrules, adhesion of particles in blocks impossible! This was the basis for selection of the Solar system, as special, from some other star systems where planets are formed, according to observations, much faster. The process of education is not done for tens of millions of years, and a few million years.
The authors introduce a new model of formation of the Solar system from a rotating disk, which contained a huge amount of energy within it. Particles merged in the jets along the drive. In the centre was formed the Sun, because the matter had lost momentum and start to get thicker. Since the material collapseall to the protoplanetary disk, monstrous explosive shock waves arose after the collisions, producing flare emission of thermal energy scattering in a few hours. These jumps energy touched KAV and Hendry, suggests J.. Connelly. This assumption is important because it illustrates the generation method by which the Universe in all protoplanetary disks can form solid particles.
According to other methods of Dating, based on the energy rushing in orbits protoplanet our Solar system, there was a prediction that Hendry formed after approximately 2 million years after the formation of the KAV. However, this time period does not coincide with astronomical observations in other planetary systems - it is much faster. We have to postulate the uniqueness of our Solar system, where this process took so much time.
Researchers from the University of Copenhagen doubted such a late formation of jondrow. This Dating is based on the sole fact: on the Dating of education of chondrules and KAV on aluminium-26, radioactive isotope contained in all meteorites of the Solar system. But aluminum-26 is the product of a supernova explosion, and its distribution in the Solar system could not be uniform, and increased in areas that were from the latest explosion nearest star.
To validate the existing Dating, they used an alternative method is the study of the amount of radioactive isotopes of lead and uranium contained in meteorites. Meteorite substance specially cleansed from surface contamination. Get a good enough match dates: KAV appeared 4 567,30 ± 0,16 million years ago, and Honky - in the period between 4 567,32 ± 0.42 and 4 564,71 ± 0,30 million years. It follows that in the Solar system is no pause between education KAV and chondrules were not. Probably, familiar to our planet was formed as quickly as is seen in other distant star systems.