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Carpenter, D.

Publications and source records attributed to Carpenter, D..

Development of Virtual Airspace Simulation Technology - Real-Time (VAST-RT) Capability 2 and Experimental Plans

The Virtual Airspace Simulation Technology - Real-Time (VAST-RT) Project, an element cf NASA's Virtual Airspace Modeling and Simulation (VAMS) Project, has been developing a distributed simulation capability that supports an extensible and expandable real-time, human-in-the-loop airspace simulation environment. The VAST-RT system architecture is based on DoD High Level Architecture (HLA) and the VAST-RT HLA Toolbox, a common interface implementation that incorporates a number of novel design features. The scope of the initial VAST-RT integration activity (Capability 1) included the high-fidelity human-in-the-loop simulation facilities located at NASA/Ames Research Center and medium fidelity pseudo-piloted target generators, such as the Airspace Traffic Generator (ATG) being developed as part of VAST-RT, as well as other real-time tools. This capability has been demonstrated in a gate-to-gate simulation. VAST-RT's (Capability 2A) has been recently completed, and this paper will discuss the improved integration of the real-time assets into VAST-RT, including the development of tools to integrate data collected across the simulation environment into a single data set for the researcher. Current plans for the completion of the VAST-RT distributed simulation environment (Capability 2B) and its use to evaluate future airspace capacity enhancing concepts being developed by VAMS will be discussed. Additionally, the simulation environment's application to other airspace and airport research projects is addressed.

Lehmer, R.↗

MASTER: An Orbiter for the Detailed Study of Vesta

MASTER (Mainbelt Asteroid Exploration/Rendezvous), a Discovery-class orbiter, will carry out a global geological and geochemical survey of Vesta. Primary goals include determining Vesta's mean density and interior structure through detailed mapping of the gravity field, imaging surface morphology at 3-m resolution, mapping mineralogy between 0.4 and 2.5 microns, and determining abundances of key elements through X-ray and gamma-ray spectroscopy. Spectroscopic evidence indicates the presence of basaltic lava flows on Vesta and suggests that impact basins may have exposed mantle materials. These possibilities, combined with the likelihood that Vesta is the ultimate source of HED meteorites, makes this asteroid an important target for a comprehensive orbiter mission. MASTER's global survey, combined with ongoing studies of HED meteorites, will be a major step in understanding the chemical, thermal, and geological evolution of Vesta. A particularly attractive opportunity involves a launch in June 2003 with arrival at Vesta in November 2009. The orbital phase of the mission is scheduled to last one year. A flyby of another mainbelt asteroid enroute to Vesta may be possible.

Veverka, J.↗

Latitudinal plasma distribution in the dusk plasmaspheric bulge - Refilling phase and quasi-equilibrium state

Very low-energy trapped ions, mostly protons, have been observed in a region of moderate density characteristic of the plasmapause boundary and of the plasmaspheric bulge. The present paper is concerned with an examination of the latitudinal structure of the bulge under quasi-steady conditions and the conditions of the recovery phase. Details regarding the data base are considered along with observations of the morphology and dynamics of the bulge, the latitudinal density distribution in the expanded bulge, the convection scenario during the replenishment phase, and latitudinal effects on plasma characteristics during plasmasphere refilling. The data utilized have been mainly provided by the DE 1 and GEOS 2 spacecraft traveling in two perpendicular planes. It is found that the bulge is a dynamic region, where no reasonable interpretation of the observed density distribution can be achieved without taking into account the mechanism of magnetospheric convection.

Decreau, P. M. E.↗