Why to people of Earth kosmokhimiya?
of Kosmokhimiya - science about a chemical composition of space bodies, laws of prevalence and distribution of chemical elements in the Universe, processes of a combination and migration of atoms at formation of space substance.
Kosmokhimiya investigates mainly to cold processes at the level atomno - molecular interactions of substances while hot in space - a plasma condition of substance, process of formation of chemical elements in stars, the physics is engaged in in nuclear processes.
Kosmokhimiya - the new area of knowledge which gained considerable development thanks to achievements of astronautics. Before research of chemical processes in a space and structure of space bodies radiations of the Sun, stars and, partly, external layers of the atmospheres of planets were carried out generally by spectral analysis . This method allowed to open an element helium on the Sun still before it was found on Earth. The analysis of chemical and phase composition of various meteorites which were dropping out to Earth was the only direct method of studying of space bodies.
Development of astronautics, flights of automatic stations to planets of Solar system - the Moon, Venus, Mars - visit by the person of the Moon opened new opportunities before a kosmokhimiya. First of all is a direct research of breeds of the Moon with the assistance of astronauts or by soil sampling by automatic devices and their delivery to Earth. Besides, automatic landers made possible studying of substance and conditions of its existence in the atmosphere and on a surface of other planets of Solar system, first of all Mars and Venus. The greatest attention is paid to problems of prevalence and distribution of chemical elements.
Chemical composition of the Sun, planets of terrestrial type of Solar system and meteorites, apparently, practically tozhdestven. Formation of kernels of chemical elements is connected with various nuclear processes in stars. Therefore at different stages of the evolution various stars and star systems have an unequal chemical composition. Stars with especially strong spectral lines of Wa, Mg, Li, etc. are known. Distribution of chemical elements on phases in space processes is exclusively various.
In space at different stages of its transformations exert versatile impact on an aggregate and phase state of substance:
1) huge range of temperatures, from star to absolute zero;
2) the huge range of pressure, from millions of the atmospheres in the conditions of planets and stars to space vacuum;
3) deeply getting galactic and solar radiations of various structure and intensity;
4) the radiations accompanying transformations of unstable atoms into stable.
At the same time processes of fractionation of substance in space concern not only nuclear, but also isotope structure. Definition of the isotope ravnovesiya which arose under the influence of radiations allows to get deeply into history of processes of formation of substance of planets, asteroids, meteorites and to establish age of these processes. Thanks to extreme conditions in a space processes proceed and the conditions of substance not peculiar to Earth meet: plasma condition of substance of stars (for example, Sun); condensation Not, CH 4 , NH 3 and other easily flying gases in the atmosphere of major planets at very low temperatures; formation of corrosion-proof iron in space vacuum at explosions on the Moon; hondritovy structure substances of stone meteorites; formation of complex organic substances in meteorites and probably on a surface of planets (for example, Mars).
Exclusive value for knowledge of chemistry of space has studying of difficult multistage process of condensation of substance of low-temperature plasma. It is transition of solar substance to the solid substance of planets of Solar system, asteroids, meteorites which is followed by the condensation growth, accretion (increase in weight, “increase“ of any substance by addition of particles from the outside, for example, from a gas-and-dust cloud) and agglomeration of primary units (phases) at simultaneous loss of volatiles in vacuum.
Further in planets there is a process of differentiation of the solid, cooling-down substance on covers - a metal kernel, silicate phases (a cloak and bark) and the atmosphere - already as a result of secondary warming up of substance of planets the warmth of a radiogenic origin which is marked out at disintegration of radioactive isotopes of potassium, uranium and thorium and, perhaps, other elements. Such process of smelting and decontamination of substance at a volcanism is characteristic of the Moon, Earth, Mars, Venus.
Safety and character of external covers of planets, first of all, depend on the mass of planets and their distance to the Sun (an example - the low-power atmosphere of Mars and the powerful atmosphere of Venus). The example of the Moon says that secondary (volcanic) gases are not kept by a celestial body if its weight is small. Thanks to proximity of Venus to the Sun in its atmosphere from CO 2 greenhouse effect arose: at a temperature over 300 about With in the atmosphere of Venus process of CaCO 3 + SiO 2 → CaSiO 3 + CO 2 reaches an equilibrium state at which it contains 97% of CO 2 with a pressure of 90 of atm . Perhaps, this future of Earth? the Institute of space researches Works with
(Moscow). There is a Geochimica et Cosmochimica Acta magazine. It is possible to esteem: Dorofeyeva V. A. Evolution of early Solar system. Kosmokhimichesky and physical aspects. M.: Editorial of URSS, 2004.