Author: W. E. MoeckelPublisher:
ISBN:
Category : Space trajectories
Languages : en
Pages : 80
Book Description
Trajectories with Constant Tangential Thrust in Central Gravitational Fields
Author: W. E. MoeckelPublisher:
ISBN:
Category : Space trajectories
Languages : en
Pages : 80
Book Description
NASA Technical Report
Author: The Theory of Diffusion in Strained Systems
Author: Louis A. GirifalcoPublisher:
ISBN:
Category : Crystals
Languages : en
Pages : 1082
Book Description
A general theory of solid-state diffusion in strained systems is developed on a molecular-kinetic basis. The theory predicts that for simple strains the diffusion coefficient is an exponential function of the lattice parameter and that the rate of change of the diffusion coefficient with strain is linearly related to the interatomic forces. It has also been shown that for plastic flow the diffusion coefficient is a linear function of strain rate. All the conclusions are confirmed by the data available in the literature.
NASA Technical Translation
Author: Starting Conditions for Nonoscillatory Low-thrust Planet-escape Trajectories
Author: Wilbur F. DobsonPublisher:
ISBN:
Category : Space vehicles
Languages : en
Pages : 20
Book Description
Theory of Geostationary Satellites
Author: Chong-Hung ZeePublisher: Springer Science & Business Media
ISBN: 9400925735
Category : Science
Languages : en
Pages : 292
Book Description
Geostationary or equatorial synchronous satellites are a daily reminder of our space efforts during the past two decades. The nightly television satellite weather picture, the intercontinental telecommunications of television transmissions and telephone conversations, and the establishrnent of educational programs in remote regions on Earth are constant reminders of the presence of these satellites. As used here, the term 'geo stationary' must be taken loosely because, in the long run, the satellites will not remain 'stationary' with respect to an Earth-fixed reference frame. This results from the fact that these satellites, as is true for all satellites, are incessantly subject to perturbations other than the central-body attraction of the Earth. Among the more predominant pertur bations are: the ellipticity of the Earth's equator, the Sun and Moon, and solar radiation pressure. Higher harmonics of the Earth's potential and tidal effects also influence satellite motion, but they are of second order when compared to the predominant perturbations. This volume deals with the theory of geostationary satellites. It consists of seven chapters. Chapter 1 provides a general discussion including a brief history of geostationary satellites and their practical applications. Chapter 2 describes the Earth's gravitational potential field and the methodology of solving the geostationary satellite problem. Chapter 3 treats the effect of Earth's equatorial ellipticity (triaxiality) on a geostationary satellite. Chapter 4 deals with the effects of the Sun and Moon on the satellite's motion while Chapter 5 presents the combined influences of the Sun, Moon and solar radiation pressure. Chapter 6 describes various station-keeping techniques which may be used to make geostationary satellites practically stationary. Finally, Chapter 7 describes the verification of the theory developed in Chapters 3, 4 and 5 by utilizing the Early Bird synchronous satellite observed data as well as its numerically integrated results.
A Parametric Study of Constant Thrust, Electrically Propelled Mars and Venus Orbiting Probes
Author: Leonard G. RossaPublisher:
ISBN:
Category : Mars probes
Languages : en
Pages : 40
Book Description
Applied Mechanics Reviews
Author: Influence of Weight Parameters on the Propulsion Requirements of Orbit-launched Vehicles
Author: Dietrich W. FellenzPublisher:
ISBN:
Category : Launch vehicles (Astronautics)
Languages : en
Pages : 112
Book Description
Author: