Space tethers are long cables which can be used for propulsion, momentum exchange, stabilization and altitude control, or maintaining the relative positions of the components of a large dispersed satellite/spacecraft sensor system. Depending on the mission objectives and altitude, spaceflight using this form of spacecraft propulsion may be significantly less expensive than spaceflight using rocket engines. A number of space tethers have been deployed in space missions. Tether satellites can be used for various purposes including research into tether propulsion, tidal stabilisation and orbital...

This report documents the Venus gravity methods and results to date (model MGNP90LSAAP). It contains many useful plots (such as geometry and orbit behavior) that are useful in evaluating the tracking data. We discuss the models that are used in processing the Doppler data and the estimation method for determining the gravity field. With Pioneer Venus Orbiter and Magellan tracking data, the Venus gravity field was determined complete to degree and order 90 with the use of the JPL Cray T3D Supercomputer. The gravity field shows unprecedented high correlation with topography and resolution of...

This handbook examines the effects of the Martian environment on radio wave propagation on Mars and in the space near the planet. The environmental effects include these from the Martian atmosphere, ionosphere, global dust storms, aerosols, clouds, and geomorphologic features. Relevant Martian environmental parameters were extracted from the measurements of Mars missions during the past 30 years, especially from Mars Pathfinder and Mars Global Surveyor. The results derived from measurements and analyses have been reviewed through an extensive literature search. The updated parameters have...

Space physics is, to a great extent, the study of naturally occurring plasmas. Approximately 99% of all the matter in the Universe exists in the form of plasmas of many different types; including the partially-ionized, relatively cool plasmas of planetary ionospheres, the million degree plasmas found in the solar corona, the solar-wind plasmas, the planetary magnetospheres, and the highly relativistic galactic cosmic-ray plasma. Not only do these plasmas have very different physical scales, but each has phenomena occurring on a wide range of scales within it. The challenge for space physics...

This handbook provides information for trajectory designers and mission planners to determine Earth-Mars and Mars-Earth mission opportunities for the years 2009-2024. These studies were performed in support of a human Mars mission scenario that will consist of two cargo launches followed by a piloted mission during the next opportunity approximately 2 years later. "Porkchop" plots defining all of these mission opportunities are provided which include departure energy, departure excess speed, departure declination arrival excess speed, and arrival declinations for the mission space surrounding...

This handbook contains graphical data necessary for the preliminary design of ballistic missions to Venus Contours of launch energy requirements, as well as many other launch and Venus arrival parameters, are presented in launch date arrival date space for all launch opportunities from 1991 through 2005. In addition, an extensive is included which explains mission design methods, from launch window development to Venus probe and orbiter arrival design, utilizing the graphical data in this volume as well as numerous equations relating various parameters. This is one of a planned series of...

This handbook contains graphical data necessary for the preliminary design of ballistic missions to Mars. Contours of launch energy requirements, as well as many other launch and Mars arrival parameters, are presented in launch date/arrival date space for all launch opportunities from 1990 through 2005. In addition, an extensive text is included which explains mission design methods, from launch window development to Mars probe and orbiter arrival design, utilizing the graphical data in this volume as well as numerous equations relating various parameters. This is one of a planned series of...

This handbook contains graphic data necessary for the preliminary design of ballistic missions to Saturn. Contours of launch energy requirements, as well as many other launch and Saturn arrival parameters, are presented in launch date/arrival date space for all launch opportunities from 1985 through 200S. In addition, an extensive text is included which explains mission design methods, from launch window development to Saturn probe and orbiter arrival design, utilizing the graphical data in this volume as well as numerous equations relating various parameters. This is the first of a planned...

This handbook contains graphical data necessary for the preliminary design of ballistic missions returning from Mars. Contours of Mars-departure energy requirements, as well as many other launch and Earth-arrival parameters, are presented in arrival-date/launch-date space for all departure opportunities from 1992 through 2007. In addition, an extensive companion document is available; it contains Earth-to-Mars graphical data and explains mission design methods, from launch-window development to Mars probe and orbiter arrival design, using the graphical data as well as numerous equations...

The purpose of this Mission Design Handbook is to provide trajectory designers and mission planners with graphical information about Earth to Mars trajectory opportunities for the years of 2026 through 2045. The trajectory data used to create the following opportunity contour plots was generated using MIDAS, a patched conic interplanetary trajectory optimization program that is able to optimize the times of specified trajectory events and other trajectory parameter. The plots, displayed on a departure date/arrival date mission space, show departure energy, right ascension and declination of...