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The article is devoted to theoretical approaches to the use of differential matrix systems for calculating the aerodynamic maneuver of satellites. The algorithm for changing the inclination of the orbital plane and the longitude of the ascending node is presented. The authors analyzed the curvature of the descent trajectory in the atmosphere to change the longitudinal and lateral descent range, taking into account the expansion of the entrance corridor. Parameters of variation of the orbital phase for phasing with another spacecraft are presented in differential matrix form, for example, when transporting a spacecraft to a meeting point with a space station. The differential matrix equation takes into account small changes in all the orbital elements for the transition to a new given orbit or for the correction of the original orbit. A priori, several of the required combinations of altitude and flight speed were selected for optimal control, the corresponding values of the parameters of the space environment in front of the satellite are determined. The parameters of the evolution of the orbits are analytically presented, which make it possible to find regions of stability on the plane of the parameters of the major semiaxis and inclination for different quantities. In this paper, the authors show analytically that the use of trajectories of a multipulse transition to high circular orbits of satellites with large inclinations increases the final mass of the satellite, and also allows the satellite to be brought to final orbits with given distance values at the point of application of the intermediate pulse. [ABSTRACT FROM AUTHOR]

A resident archive for Level 2 dataset (derived and expert-annotated products) of the radio plasma imager (RPI) on NASA IMAGE spacecraft has been operated at UMLCAR since 2001. The archive provides a much needed, publicly available annotation service for the voluminous collection of RPI data whose interpretations become available to the wave instrument community. Both human and automatically generated annotations are stored in the database server at UMLCAR, remotely accessible over the Internet for both data retrieval and submission of the annotations. Available annotations can be used for the content-based data retrieval of only relevant measurements by non-expert users. The paper discusses implementation details of the Level 2 interactive data archive. [ABSTRACT FROM AUTHOR]

In January 2001, the X-50LR program was initiated to scale the Lightcraft concept ultimately to a 50-cm focal diameter, and to launch a 50 cm, fully functional vehicle, into space in either a sounding rocket or suborbital trajectory by the end of FY 2009. The current work involves scaling from the 10-cm aluminum Lightcraft to a fully composite 25-cm laser ramjet vehicle (X-25LR). An overview and status of this program will be given in terms of the various efforts that support this development. These efforts will include testing at the High Energy Laser System Test Facility (HELSTF), New Mexico; some results of the laser launch system study by Flight Unlimited; supporting research by the Air Force Office of Scientific Research (AFOSR); the different facets of attitude control in a small business program with Polaris Sensors Technology; continuing development of a launch model at The Pennsylvania State University; and, the development of a thrust measurement technique, and the use of a “mini-thruster” for research with The University of Alabama, Huntsville in collaboration with the AFRL. This paper will be followed by a number of papers giving additional details of the efforts briefly overviewed in this presentation. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper presents results from ion thruster modeling studies performed in support of NASA's Deep Space 1 mission and NSTAR project. Fully 3-dimensional computer particle simulation models are presented for ion optics plasma flow and ion thruster plume. Ion optics simulation results are compared with measurements obtained from ground tests of the NSTAR ion thruster. Plume simulation results are compared with in-flight measurements from the Deep Space 1 spacecraft. Both models show excellent agreement with experimental data. [ABSTRACT FROM AUTHOR]

The Orbital Express (OE) mission performed the first autonomous rendezvous and docking in the history of the United States on May 5–6, 2007 with the Advanced Video Guidance Sensor (AVGS) acting as one of the primary docking sensors. Since that event, the OE spacecraft performed four more rendezvous and docking maneuvers, each time using the AVGS as one of the docking sensors. The Marshall Space Flight Center's (MSFC's) AVGS is a near-field proximity operations sensor that was integrated into the Autonomous Rendezvous and Capture Sensor System (ARCSS) on OE. The ARCSS provided the relative state knowledge to allow the OE spacecraft to rendezvous and dock. The AVGS is a mature sensor technology designed to support Automated Rendezvous and Docking (AR&D) operations. It is a video-based laser-illuminated sensor that can determine the relative position and attitude between itself and its target. Due to parts obsolescence, the AVGS that was flown on OE can no longer be manufactured. MSFC has been working on the next generation of AVGS for application to future Constellation missions. This paper provides an overview of the performance of the AVGS on Orbital Express and discusses the work on the Next Generation AVGS (NGAVGS). [ABSTRACT FROM AUTHOR]

This paper covers the initial work oriented to develop a semi-perpetual rotary machine propelled by laser ablation propulsion. The laser is equipped with a pulse repetition frequency tuned to the rotational frequency of the flying wheel. Purpose of this work is to establish the potentiality of a self-sustained closed system capable of generating kinetic rotary energy which can be exploited for traction of vehicles and production of electrical energy at very low cost. The work presented is in process of being patented. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The increased use of smaller spacecraft over the last decade, in combination with studies of potential science applications, has suggested the need for Radioisotope Power Systems (RPSs) yielding much lower power levels than the 100 watt-scale devices used in the past. Small milliwatt to multiwatt-scale RPS units have the potential to extend the capability of small science payloads and instruments, and to enable many new mission applications. Such units could also find application in future human exploration missions involving use of monitoring stations and autonomous devices, similar to the ALSEP units deployed on the Moon during the Apollo program. Although flight-qualified RPS units in this size and power range do not presently exist, their potential to support a broad range of exploration tasks has led NASA and the Department of Energy (DOE) to consider the development of small-RPS units such that they might be available for missions by the early part of next decade. This paper summarizes the results of activities to date and provides possible options for future development. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The GLAST Burst Monitor (GBM) consists of 12 NaI detectors and 2 BGO detectors mounted on two sides of the spacecraft. This provides detection capability for energies between 10 keV and 30 MeV, and sensitivity to all directions in the sky. Extensive measurements using radioactive sources have been performed on the isolated detectors. Simulations of these measurements using the GEANT4 Monte Carlo radiation transport simulations toolset have also been preformed. For gamma-ray burst the spacecraft itself will have a significant impact on the detector response, therefore the final stage of validations involves measuring the detector response to radioactive sources after the spacecraft is fully assembled, and validating the results using simulation. Details of these simulations will be given in this paper. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper presents a brief history of the laser lightcraft research and development project that lead to the first outdoor free-flight demonstrations for the U.S. government on November 1997 - using the 10 kW PLVTS CO2 laser at the High Energy Laser Systems Test Facility (HELSTF), White Sands Missile Range (WSMR), NM. Summarized herein are some of the technological milestones that brought the Lightcraft Technology Demonstrator (LTD) concept vehicle to its present state of development: 1) from the initial LTD conceptual design, systems integration, and performance analysis for the Strategic Defense Initiative Organization (SDIO); 2) through laboratory engine bench testing, indoor wire-guided and vertical free-flight testing phases under contract to NASA and the USAF; and 3) finally resulting in outdoor flights to the current record altitude of 71 meters (233 ft) on 2 October 2000, sponsored by the Foundation for International Non-governmental Development of Space (FINDS). [ABSTRACT FROM AUTHOR]

Space weathering by the plasma and energetic particle radiation environment of the heliosphere contributes to the physical and chemical evolution of exposed surfaces on airless bodies such as the Moon, asteroids, comets, and icy bodies of the outer solar system. The Multi-Source Spectral Plot (MSSP) service of the NASA Virtual Energetic Particle Observatory (VEPO) enables enhanced access and comparative global heliospheric analysis of ion flux spectra from the past and present fleet of interplanetary spacecraft for modeling of space weathering effects. Commonly red colors of low-inclination Classical Kuiper Belt Objects may be the result of specific compositional origin and spectral irradiation effects in the outer heliosphere. VEPO also enables easy comparison of flux spectra to check intercalibration issues. [ABSTRACT FROM AUTHOR]

We propose a Lorentz-covariant theory of gravity, and explain its theoretical origins in the problem of time in Newtonian physics. In this retarded gravitation theory (RGT), the gravitational force depends upon both retarded position and velocity, and the equations of motion are time-asymmetric retarded functional differential equations. We explicitly solve these equations, under simplifying assumptions, for various NASA spacecraft. This shows that the differences from Newtonian gravity, though tiny within the solar system, are just appropriate to explain the flyby anomaly as a νc effect due to earth's rotation. The differences can, however, be large in the case of a spiral galaxy, and we show that the combined velocity drag from a large number of co-rotating stars enormously speeds up a test particle. Thus, the non-Newtonian behaviour of rotation curves in a spiral galaxy may be explained as being due to velocity drag rather than dark matter. RGT can also be tested in the laboratory. It necessitates a reappraisal of current laboratory methods of determining the Newtonian gravitational constant G. Since RGT makes no speculative assumptions, its refutation would have serious implications across physics. [ABSTRACT FROM AUTHOR]