SELF

O. N. Karavashkina and S. B. Karavashkin.

30

Some aspects of the Earth evolution

S.K. Vsehsvyatsky shared such view: "We have good grounds to think the primary planets (protoplanets) the bodies of stellar nature… The Sun could be a component of a stellar system remained after the second component has divided into smaller parts because of burst" [43, p. 378- 379]. The burst of this satellite "occurred, probably, on account of burst-like change of the internal protostellar substance. 'The 'splinters' of the satellite were small, so they fast cooled down, wherethrough there originated the complex molecular compounds and solid envelops of future planets" [35, p. 43]. Here we see some uncertainty of, what Vsehsvyatsky means under 'fast cooling', which disables to judge surely, how much substantiated this view is. If this cooling lasted dozens or hundreds million years, we can hardly call it fast, but then the gradual evolution could lead to the composition of complex molecular compounds. But if Vsehsvyatsky means dozens or hundreds thousand years, such cooling would, on the contrary, impede the composition of complex molecular compounds and regular spheres of planets, as we will substantiate it in the following chapters.

V.G. Gorbatsky expressed an interesting thought, also supposing that planet systems can origin from the burst of new stars. In Fig. 1.13 taken from his book [44] we can see the sequence, how the planetary nebula forms (New of Eagle, 1918): "In few years after the burst, around the new star we often see a light nebula shaped as a regular circumstance or ellipse resembling the planetary nebula. Its spectrum consists of emission lines, and this means, the nebula was formed of rare luminescent gas. The visible radius of nebula, i.e. the angle at which we see it, grows with time" [44, p. 113]. This aspect is important in the view that, as Gorbatsky points, there burst as new "the dwarfs having the radius an order less than the Sun and the mass few times less than the Sun. If we distribute the mass of envelop along the entire surface of such star, about 10⁸ g of substance will fall at 1 sm² of this surface. The atmosphere of the star that falls at1 sm² is about few grams. Hence, the blasted substance composed both the photosphere and the depths. The pressure at the level where the burst occurred… has to be about 10^13- 10¹⁴ g/sm*sec², i.e. millions times more than in the star atmosphere. Accordingly, there has to be very high temperature - millions degrees, and high density of gas. Of course, the layers over the level of burst would be absolutely opaque for the radiation of any wavelength. Judging by the approximately spherical shape of the nebula formed in the burst of nova, we can admit that the burst encompasses the entire layer of the star at its definite level. So the thrown off envelop has the spherical shape, just as the star surface, though the power of burst can be, apparently, not the same at different directions, which causes sometimes the observed 'one-side' nebulas" [44, p. 115- 116].

Fig.1.13. Photos of the New of Eagle at different years show the envelop growing. At the photos of 1933 and 1940 we can see some formation - the gas clot at the end of axis of envelop (shown by the arrow) [44, Fig. 32, p. 113].

We can notice by the way that a nebula is spherical only initially. Its substance fast orients in the Galaxy field and shrinks into a ring, as we clearly see it in Fig. 3 and due to which they were called planetary, by analogy with the ring models of Kant and Laplace.

Now we see that long process of Protoearth modelling permanently bumps into the process of protoplanet nebula formation. Dependently on its properties, some or other physical processes (or set of processes) are possible, which in each case can lead to the planet system formation. The mankind in its comprehension of phenomena and processes has covered a long way of cognition and achieved the conceptual understanding and observation corroboration of many cosmologic phenomena, but by T. Bart's opinion, even up to now "the Earth origin is shrouded in mystery. Neither Kant - Laplace hypothesis, nor Moulton and Chamberlin theories and their kinds, nor pure tidal theories by Gins and Jeffreys which were recognised during many years could not withstand the test in the light of contemporary scientific data. Despite this statement, in each of hypotheses mentioned by T. Bart we see something that could shed light on the problem" [34, p. 13]. We will try to keep this principle in constructing our model.

Only having linked the conditions of a protoplanet cloud formation with the known for today experimental data and observation data of the stars/stellar systems evolution, on one hand, and the conditions of the planetary nebulas formation on the other, we can expect to obtain more or less trustworthy pattern of origin and evolution of the planetary system. This point is basically important, because, having constructed a non-contradictive phenomenology of the process of protoplanet cloud formation, we in this way will lift many of root discrepancies also in description of initial stages of the Earth evolution that are present in the conventional hypotheses, due to their great discrepancy in predicting the initial energy of the planets that are formed. In this aspect, the conceptions diametrically differ: if some scientists adhered to a cold origin, they indispensably mean absolutely cold, with even gases frozen, body; if hot, "star" origin, then "the hot cloud of gas cooled down, gradually emanating the heat from its surface. During approximately few dozen thousand years the gaseous Protoearth turned into a hot igneous-liquid body… Having fast 'layered', the Earth went on cooling and with time covered with the solid crust… This rough scheme of evolution seemed before war so obvious that any ideas of the primary cold state of the Earth were rejected as eccentric. Today 'hot' cosmogonic hypotheses are evaluated otherwise… First of all it is unclear, how namely the hot gaseous cloud separated from Sun or from its star satellite that had burst. Meanwhile we have only some general qualitative considerations not substantiated by quantitative calculations. Instead, there are calculations showing that the gaseous cloud with a mass approximately alike the Earth mass should rather dissipate in space than to condensate into a liquid planet. There are also other serious objections against the 'hot' birth of the Earth… The 'hot' version of the Earth birth well explains the high temperature of its central region (the primary igneous-liquid Earth cooled down from the surface). Instead, it is unclear, why the differentiation, 'settling' of the Earth substance is still on: in the igneous-liquid mass the heavy matter would long ago fall down to the centre, and the lightest would concentrate to the surface" [35, p. 47- 48].

To answer these questions, we need to model correct initial state of the protoplanet nebula. So, noting the results of above analysis, we will begin our investigation of the Earth evolution just with studying the conditions of the protoplanet nebula formation which would satisfy all necessary conditions of the following planet system formation. With it we will endeavour to lift the existing discrepancies, and on this basis step by step we will try to reconstruct the sequence of the evolution.