Аннотация:Abstract
The cosmic environment of Earth directly or indirectly influences conditions for terrestrial life. Cosmic influences include increased fluxes of gas, dust, comets and asteroids, as well as cosmic rays (energetic particles of galactic and solar origin), interplanetary plasma (solar wind) and electromagnetic emission of various energies. The main emphasis of this paper is on the radiation conditions and their variations, especially in the remote past (at geological scale of time). The Sun, the most important pre-condition for terrestrial life, is also discussed as a potential source of dangerous emissions. We briefly review and update recent observational data and research works concerning the frontier between Astrobiology and Space Weather. Our attention is mainly paid to cosmic rays of galactic and solar origin (GCR and SCR, respectively). Regular GCR variations in the deep past of the Solar system, as well as the occurrence rates of sporadic events, namely, the Supernova bursts and giant solar flares, are considered in detail. In this field, there are still many astrophysical and biological problems to be investigated from the modern positions, taking into account new models of galactic evolution and experimental evidences of important contribution of cosmic rays into the evolution of the biosphere. The present robust programs of space research reinforce our hope for a better understanding of the bases of Astrobiology. In particular, a contribution of the nearest dwarf stars into cosmic rays flux at the Earth’s orbit seems to be revised in the light of latest observational data. Eventually, with a more realistic model of the Sun, more reliable discussions of all the factors influencing the origin of life on Earth will be also possible.