Space research

Abstract: The effects of the space radiation environment on spacecraft systems and instruments are significant design considerations for space missions Astronaut exposure is a serious concern for manned missions In order to meet these challenges and have reliable, cost-effective designs, the radiation environment must be understood and accurately modeled The nature of the environment varies greatly between low earth orbits and higher earth orbits There are both short-term and long-term variations with the phase of the solar cycle In this paper we concentrate mainly on charged particle radiations in the near-Earth region Descriptions of the radiation belts and particles of solar and cosmic origin are reviewed An overview of the traditional models is presented accompanied by their application areas and limitations This is followed by discussion of some recent model developments

Abstract: Nearly all of the satellites now in orbit feel the effects of atmosphere drag. This book, written by a highly respected author with a lifetime's experience in space research, presents a concise and up-to-date study of the mathematical formulation needed to understand and specify their motion. The early chapters develop the theory, first for a spherical atmosphere, then for various more realistic models, e.g. an oblate atmosphere or one with density varying between day and night. Two later chapters show how to apply the theory in analysing the orbits of real satellites to determine air density, winds and other atmospheric parameters. Practical methods are presented for predicting the lifetimes of satellites, and the theory is also applied to orbits about Mars and Venus. This book will be of special interest to lecturers, postgraduates and researchers in applied mathematics, applied physics, space research, geophysics and aerospace. Contents Introduction. The atmosphere and its action on a satellite. Basic theory. Orbital theory for a spherically symmetrical, exponential atmosphere. Orbital theory for an oblate, exponential atmosphere. Orbital theory when atmospheric scale height varies with altitude. Orbital theory for an atmosphere with day-to-night density variation. Effect of atmospheric rotation on the orientation of the orbital plane. Extensions and alternatives. Adaptation of the theory for use in atmospheric research. The theory in action. Predicting satellite lifetimes. Orbits about Mars and Venus. Appendix: The Earth's gravitational field. References. Further reading. Index.