NASA uses aerobraking (AB) to reduce the fuel required to deliver a spacecraft into its desired final orbit around a target planet or moon with a significant atmosphere. Instead of using the propulsion system to decelerate the spacecraft, AB utilizes aerodynamic drag. While flying through the upper atmosphere of the planet or moon multiple times, the spacecraft maintains a periapsis control corridor such that dynamic pressure and thermal loads on the spacecraft remain within designed parameters. AB has been used four times by NASA: once at Venus and three times at Mars. Although AB reduces...

Phase 1 of the Development of Autonomous Aerobraking (AA) Assessment investigated the technical capability of transferring the processes of aerobraking maneuver (ABM) decision making (currently performed on the ground by an extensive workforce and communicated to the spacecraft via the deep space network (DSN) to an efficient flight software algorithm onboard the spacecraft. To accomplish this, aerodynamic and thermal models for a representative spacecraft were developed for the onboard algorithm known as AA development software (AADS) and a ground-based "truth" simulation developed for...

Probabilistic Risk Assessment (PRA) is a comprehensive, structured, and logical analysis method aimed at identifying and assessing risks in complex technological systems for the purpose of cost-effectively improving their safety and performance. NASA's objective is to better understand and effectively manage risk, and thus more effectively ensure mission and programmatic success, and to achieve and maintain high safety standards at NASA. NASA intends to use risk assessment in its programs and projects to support optimal management decision making for the improvement of safety and program...

The technical report embodied in this volume is a compilation of articles reflecting the current state of knowledge on the physics, chemistry, astronomy, and aeronomy of small bodies in the Solar System. The articles reported here represent the most recent scientific results in meteor, meteoroid, and related research fields and were presented at the Meteoroids 2010 Conference. Meteoroids 2010 was the seventh conference in a series of meetings on meteoroids and related topics, which have been held approximately every 3 years since the first one celebrated in 1992 in Smolenice Castle, Slovakia....

The National Aeronautics and Space Administration is investigating alternative approaches, technologies, and communication network architectures to facilitate building the Spaceports and Ranges of the future. These investigations support the Second Generation Reusable Launch Vehicle (2nd Gen RLV), and other associated craft presently under development in Government, academic, and private sectors, and provide a national centralized R&D forum for next-generation Spaceport and Range technology development. These sectors all share the common goal of changing the historic risk/reward equation for...

This volume is the proceedings of the sixth General Meeting of the International VLBI Service for Geodesy and Astrometry (IVS), held in Hobart, Tasmania, Australia, February 7-13, 2010. The sixth General Meeting was held in Hobart, Tasmania, Australia on the Sandy Bay Campus of the University of Tasmania. The meeting was hosted by the University of Tasmania, School of Mathematics and Physics, which supports the IVS Network Station at Hobart and is responsible for managing the AuScope project. The keynote of the sixth General Meeting was new perspectives of the next generation VLBI system...

Radioisotope Electric Propulsion (REP) has been shown in past studies to enable missions to outer planetary bodies including the orbiting of Centaur asteroids. Key to the feasibility for REP missions are long life, low power electric propulsion (EP) devices, low mass Radioisotope Power System (RPS) and light spacecraft (S/C) components. In order to determine the key parameters for EP devices to perform these REP missions a design study was completed to design an REP S/C to orbit a Centaur in a New Frontiers (NF) cost cap. The design shows that an orbiter using several long lived (approx. 200...

The COllaborative Modeling and Parametric Assessment of Space Systems (COMPASS) team was approached by the NASA Glenn Research Center (GRC) In-Space Project to perform a design session to develop Radioisotope Electric Propulsion (REP) Spacecraft Conceptual Designs (with cost, risk, and reliability) for missions of three different classes: New Frontier's Class Centaur Orbiter (with Trojan flyby), Flagship, and Discovery. The designs will allow trading of current and future propulsion systems. The results will directly support technology development decisions. The results of the Flagship...

NASA accomplishes its strategic goals through human and robotic exploration missions. Many of these missions require launching and landing or returning spacecraft with human or return samples through Earth's and other planetary atmospheres. Spacecraft entering an atmosphere are subjected to extreme aerothermal loads. Protecting against these extreme loads is a critical element of spacecraft design. The safety and success of the planned mission is a prime concern for the Agency, and risk mitigation requires the knowledgeable use of thermal protection systems to successfully withstand the...

This report presents the scientific, technological, and flight project achievements of the Goddard Space Flight Center (GSFC) Heliophysics Science Division (HSD) for FY09. HSD consists of 299 scientists, technologists, engineers, education and public outreach specialists, and administrative personnel dedicated to advancing our knowledge and understanding of the Sun and the wide variety of domains influenced by its variability. HSD's Mission is to explore the Sun's interior and atmosphere, discover the origins of its temporal variability, understand its influence over the Earth and the other...