The Formation of the Earth from Cold 



Material and the Problem of the Formation 



of the Simplest Organic Substances 



B. Yu. LEVIN 



O. Shmidt Institute of Geophysics 

 of the Academy of Sciences of the U.S.S.R., 

 Moscow 



One aspect of the problem of the origin of life may be formulated as the following 

 question: How, and under what conditions did the abiogenic synthesis of 

 organic compounds take place and lead to the appearance on our Earth of 

 organisms, which later became the major synthesizers of these compoimds ? 

 To obtain an answer to this question it is necessary to survey the history of the 

 whole substance of our planet, as this history determines how far abiogenic 

 synthesis could proceed and what was the state of the Earth at the time when 

 life came into being. 



I. Let us begin with the question of the time and place of the original forma- 

 tion of the organic compovmds which is most closely asssociated with the 

 question of the formation of the Earth. For a long time there prevailed, among 

 those who studied the formation of planets, hypotheses according to which the 

 Earth and other planets were formed from aggregations of incandescent gaseous 

 material. At temperatures of several thousands of degrees C organic compounds 

 cannot exist. These hypotheses therefore led to the assumption that organic 

 compounds were only formed after the formation and sufficient cooUng of the 

 Earth. 



At present there prevails, among students of the origin of planets, a different 

 opinion as to the 'original' state of the planetary material. Almost all contemporary 

 hypotheses concerning the origin of the planets regard them as having been 

 formed from a cold cloud of gas and dust which at one time encircled the 

 Sun. In such a cloud the simplest organic compounds must have been present, 

 just as they are present elsewhere in the interstellar gases. 



However, the unanimity with which those who study the origin of the planets 

 agree about the 'original' state of the planetary material does not mean that the 

 authors of theories about this subject are unanimous in their ideas about its 

 further evolution, the actual process of formation of planets. In particular, and 

 this is very important in connection with the problem we are considering, 

 different workers have different views as to the later thermal history of the 

 original material of dust and gas. Thus Kuiper [i, 2] considers that very massive 

 protoplanets composed of dust and gas must have been formed within the cloud 

 of dust and gas. He claims that their compression, in the course of their trans- 



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