Surgery benefits from defense technology: dual use applications ofWright Laboratory Avionics technologies to Computer Assisted MinimallyInvasive Surgery (CAMIS)

Wright Laboratory Avionics Directorate is helping to assemble a team of defense and civilian researchers to transition defense avionics and related technologies to the medical community with the goal of improving the Computer Assisted Minimally invasive Surgery (CAMIS) concept. Key partners include Ohio Aerospace Institute (OAI), a not-for-profit state-chartered agency, Cleveland Clinic Foundation hospital, and Picker International, medical equipment manufacturer. The CAMIS concept is in response to the fact that despite technical advances, most excision surgeries are exploratory rather than remedial. As a result, large incisions are required so the surgeon can first search for the “target” tissue and then, more cutting is needed to remove or destroy the “target”. CAMIS is an opportunity to transition defense avionics technologies to help tackle a critical non-defense issue on the national agenda, health care     

Dynamics of the earth's ring current: Theory and observation

The development of currents within an arbitrary distribution of particles trapped in the geomagnetic field is described. These currents combine to form the earth's ring current and thus are responsible for the worldwide depressions of surface magnetic field strength during periods of magnetic activity known as magnetic storms. Following a brief review of trapped particle motion in magnetic fields, ring current development is described and presented in terms of basic field and particle distribution parameters. Experimental observations then are presented and discussed within the theoretical framework developed earlier. New results are presented which, in the area of composition and charge state observations, hold high promise in solving many long standing ring current problems. Finally, available experimental results will be used to assess our present understanding as to ring current sources, generation, and dissipation.     

Three-dimensional energetic ion observations and the tangential magnetopause electric field

Three-dimensional distributions for 24.0–44.5 keV protons (ions) are presented from the ISEE-1 medium energy particles instrument during a magnetopause traversal at 01:10 UT on 20 November 1977. Local time of the traversal was 1030. Ion fluxes were observed coming generally from the subsolar region, but over a wide range of latitudes. Enhanced fluxes were observed at the magnetopause crossing with strong components from the subsolar region and from the +Z _SE direction. These observations are compared with the simultaneous electric field observations presented by Mozer et al. (1978). Ion streaming in a direction consistent with the Y-component of the drift velocity was observed whereas streaming along the X and Z-components is not seen. Based on energy arguments we conclude that in this case, 24 keV ions are not the major energy carrier of the locally measured · dissipation.     

The X-Ray Spectrometer on the MESSENGER Spacecraft

NASA’s MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) mission will further the understanding of the formation of the planets by examining the least studied of the terrestrial planets, Mercury. During the one-year orbital phase (beginning in 2011) and three earlier flybys (2008 and 2009), the X-Ray Spectrometer (XRS) onboard the MESSENGER spacecraft will measure the surface elemental composition. XRS will measure the characteristic X-ray emissions induced on the surface of Mercury by the incident solar flux. The Kα lines for the elements Mg, Al, Si, S, Ca, Ti, and Fe will be detected. The 12° field-of-view of the instrument will allow a spatial resolution that ranges from 42 km at periapsis to 3200 km at apoapsis due to the spacecraft’s highly elliptical orbit. XRS will provide elemental composition measurements covering the majority of Mercury’s surface, as well as potential high-spatial-resolution measurements of features of interest. This paper summarizes XRS’s science objectives, technical design, calibration, and mission observation strategy.     

COMPTEL observations of AGNs

During the first part of the COMPTON Gamma Ray Observatory sky survey, COMPTEL has detected the quasars 3C273 and 3C279 and the radio galaxy Centaurus A. This paper summarizes the preliminary findings and gives an upper limit on the MeV flux of the Seyfert galaxy NGC4151.     

The Galileo Energetic Particles Detector

Amongst its complement of particles and fields instruments, the Galileo spacecraft carries an Energetic Particles Detector (EPD) designed to measure the characteristics of particle populations important in determining the size, shape, and dynamics of the Jovian magnetosphere. To do this the EPD provides 4 angular coverage and spectral measurements for Z 1 ions from 20 keV to 55 MeV, for electrons from 15 keV to > 11 MeV, and for the elemental species helium through iron from approximately 10 keV nucl^-1 to 15 MeV nucl^-1. Two bi-directional telescopes, mounted on a stepping platform, employ magnetic deflection, energy loss versus energy, and time-of-flight techniques to provide 64 rate channels and pulse height analysis of priority selected events. The EPD data system provides a large number of possible operational modes from which a small number will be selected to optimize data collection during the many encounter and cruise phases of the mission. The EPD employs a number of safeing algorithms that are to be used in the event that its self-checking procedures indicate a problem. The EPD has demonstrated its operational flexibility throughout the long evolution of the Galileo program by readily accommodating a variety of secondary mission objectives occasioned by the changing mission profile, such as the Venus flyby and the Earth 1 and 2 encounters. To date the EPD performance in flight has been nominal. In this paper we describe the instrument and its operation.     

Communication from Mars: Requirements and Limitations

The exploration of our nearest planets will require relaying large amounts of data to Earth for study and evaluation. However, our ability to communicate at interplanetary distances is limited. In this paper, an evaluation is made of our capability to communicate from the vicinity of Mars using the present S-band deep-space network, prospects for enhancing that performance, and limitations beyond which no additional improvement seems feasible. In addition, requirements for real-time television are evaluated and prospects for improving the communication rates by operating at higher microwave frequencies considered.     

Instrument Boom Mechanisms on the THEMIS Satellites; Magnetometer, Radial Wire, and Axial Booms

The five “Time History of Events and Macroscale Interactions during Substorms” (THEMIS) micro-satellites launched on a common carrier by a Delta II, 7925 heavy, on February 17, 2007. This is the fifth launch in the NASA MeDIum class EXplorer (MIDEX) program. In the mission proposal the decision was made to have the University of California Berkeley Space Sciences Laboratory (UCB-SSL) mechanical engineering staff provide all of the spacecraft appendages, in order to meet the short development schedule, and to insure compatibility. This paper describes the systems engineering, design, development, testing, and on-orbit deployment of these boom systems that include: the 1 and 2 meter carbon fiber composite magnetometer booms, the 40 and 50 m tip to tip orthogonal spin-plane wire boom pairs, and the 6.3 m dipole stiff axial booms.     

Magnetospheric plasma sources and losses: future directions

Space Science Reviews -