ABSTRACT
A discussion of the present knowledge of element synthesis processes and resulting abundance curves of the solar system is presented in this chapter. The element abundance curves are the result of the processes of element synthesis, which started with the p–p chain at the beginning of the Universe, some 13.75 × 109 years ago. According to the Big Bang nucleosynthesis theory, the universal abundances of 2H, 3He, 4He and 7Li are fixed in the first few minutes. The elemental composition of the Universe remained unchanged until the formation of the first stars, when nucleosynthesis in stars commenced. These stars used hydrogen as fuel, creating heavier elements such as carbon and oxygen and up to the element iron through the nuclear fusion processes. The supernova explosions spread material into interstellar space. The high energies of such an explosion created additional elements heavier than iron. Some of the metals, such as silicon and iron, combined with oxygen to form dust particles. A small part of the giant molecular cloud, with well-defined chemical and isotopic composition, collapsed because of gravitation, resulting in the formation of the solar system. Element abundances of any object in the Universe change with time.
