Composition of Light Solar Wind Noble Gases in the Bulk Metallic Glass flown on the Genesis Mission

We discuss data of light noble gases from the solar wind implanted into a metallic glass target flown on the Genesis mission. Helium and neon isotopic compositions of the bulk solar wind trapped in this target during 887 days of exposure to the solar wind do not deviate significantly from the values in foils of the Apollo Solar Wind Composition experiments, which have been exposed for hours to days. In general, the depth profile of the Ne isotopic composition is similar to those often found in lunar soils, and essentially very well reproduced by ion-implantation modelling, adopting the measured velocity distribution of solar particles during the Genesis exposure and assuming a uniform isotopic composition of solar wind neon. The results confirm that contributions from high-energy particles to the solar wind fluence are negligible, which is consistent with in-situ observations. This makes the enigmatic "SEP-Ne” component, apparently present in lunar grains at relatively large depth, obsolete. 20Ne/ 22Ne ratios in gas trapped very near the metallic glass surface are up to 10% higher than predicted by ion implantation simulations. We attribute this superficially trapped gas to very low-speed, current-sheet-related solar wind, which has been fractionated in the corona due to inefficient Coulomb dra

Applications of graphics to support a testbed for autonomous space vehicle operations

Researchers describe their experience using graphics tools and utilities while building an application, AUTOPS, that uses a graphical Machintosh (TM)-like interface for the input and display of data, and animation graphics to enhance the presentation of results of autonomous space vehicle operations simulations. AUTOPS is a test bed for evaluating decisions for intelligent control systems for autonomous vehicles. Decisions made by an intelligent control system, e.g., a revised mission plan, might be displayed to the user in textual format or he can witness the effects of those decisions via out of window graphics animations. Although a textual description conveys essentials, a graphics animation conveys the replanning results in a more convincing way. Similarily, iconic and menu-driven screen interfaces provide the user with more meaningful options and displays. Presented here are experiences with the SunView and TAE Plus graphics tools used for interface design, and the Johnson Space Center Interactive Graphics Laboratory animation graphics tools used for generating out out of the window graphics

Isotopic Composition of Solar Wind Calcium: First in Situ Measurement by CELIAS/MTOF on Board SOHO

We present first results on the Ca isotopic abundances derived from the high resolution Mass Time-of-Flight (MTOF) spectrometer of the charge, element, and isotope analysis system (CELIAS) experiment on board the Solar and Heliospheric Observatory (SOHO). We obtain isotopic ratios 40Ca/42Ca = (128+-47) and 40Ca/44Ca = (50+-8), consistent with terrestrial values. This is the first in situ determination of the solar wind calcium isotopic composition and is important for studies of stellar modeling and solar system formation since the present-day solar Ca isotopic abundances are unchanged from their original isotopic composition in the solar nebula.Comment: 14 pages, 3 figure

Coral Disease and Health Workshop: Coral Histopathology II

The health and continued existence of coral reef ecosystems are threatened by an increasing array of environmental and anthropogenic impacts. Coral disease is one of the prominent causes of increased mortality among reefs globally, particularly in the Caribbean. Although over 40 different coral diseases and syndromes have been reported worldwide, only a few etiological agents have been confirmed; most pathogens remain unknown and the dynamics of disease transmission, pathogenicity and mortality are not understood. Causal relationships have been documented for only a few of the coral diseases, while new syndromes continue to emerge. Extensive field observations by coral biologists have provided substantial documentation of a plethora of new pathologies, but our understanding, however, has been limited to descriptions of gross lesions with names reflecting these observations (e.g., black band, white band, dark spot). To determine etiology, we must equip coral diseases scientists with basic biomedical knowledge and specialized training in areas such as histology, cell biology and pathology. Only through combining descriptive science with mechanistic science and employing the synthesis epizootiology provides will we be able to gain insight into causation and become equipped to handle the pending crisis. One of the critical challenges faced by coral disease researchers is to establish a framework to systematically study coral pathologies drawing from the field of diagnostic medicine and pathology and using generally accepted nomenclature. This process began in April 2004, with a workshop titled Coral Disease and Health Workshop: Developing Diagnostic Criteria co-convened by the Coral Disease and Health Consortium (CDHC), a working group organized under the auspices of the U.S. Coral Reef Task Force, and the International Registry for Coral Pathology (IRCP). The workshop was hosted by the U.S. Geological Survey, National Wildlife Health Center (NWHC) in Madison, Wisconsin and was focused on gross morphology and disease signs observed in the field. A resounding recommendation from the histopathologists participating in the workshop was the urgent need to develop diagnostic criteria that are suitable to move from gross observations to morphological diagnoses based on evaluation of microscopic anatomy. (PDF contains 92 pages

Determination of Interstellar O Parameters Using the First Two Years of Data from the Interstellar Boundary Explorer

The direct measurements of interstellar matter by the Interstellar Boundary Explorer ( IBEX ) mission have opened a new and important chapter in our study of the interactions that control the boundaries of our heliosphere. Here we derive for the quantitative information about interstellar O flow parameters from IBEX low-energy neutral atom data for the first time. Specifically, we derive a relatively narrow four-dimensional parameter tube along which interstellar O flow parameters must lie. Along the parameter tube, we find a large uncertainty in interstellar O flow longitude, 76°.0 ± 3°.4 from χ 2 analysis and 76°.5 ± 6°.2 from a maximum likelihood fi t, which is statistically consistent with the fl ow longitude derived for interstellar He, 75°.6 ± 1°.4. The best-fit O and He temperatures are almost identical at a reference flow longitude of 76°, which provides a strong indication that the local interstellar plasma near the Sun is relatively unaffected by turbulent heating. However, key differences include an oxygen parameter tube for the interstellar speed (relation between speed and longitude) that has higher speeds than those in the corresponding parameter tube for He, and an upstream flow latitude for oxygen that is southward of the upstream flow latitude for helium. Both of these differences are likely the result of enhanced filtration of interstellar oxygen due to its charge-exchange ionization rate, which is higher than that for helium. Furthermore, we derive an interstellar O density near the termination shock of - + - 5 .8 X 10^-5 cm that, within uncertainties, is consistent with previous estimates. Thus, we use IBEX data to probe the interstellar properties of oxygen

Depth-dependent fractionation of light solar wind noble gases in a Genesis target

We analyzed light noble gases in a bulk metallic glass (BMG) that was exposed to solar wind (SW) irradiation on Genesis for its total exposure time and all SW regimes [1]. The BMG was especially designed to look for a putative solar energetic particle (SEP) component, reported to be present in lunar soils [2], by using the closed system stepwise etching (CSSE) technique. Here we present the depth distribution of He and Ne isotopes and discuss different processes leading to the observed fractionation patterns. Moreover, this will be compared with measurements of Ar isotopes that are actually in progress

Argon, krypton, and xenon abundances in the solar wind measured in silicon from the genesis mission

Up to now solar wind (SW) abundances of Kr and Xe have been exclusively determined using SW irradiated regolith [1]. Hence, one of Genesis’s major objectives is to obtain the heavy noble gas composition of the present-day SW using artificial targets exposed to the SW for 2.5 years. SW abundances will allow to study fractionation processes upon SW formation, e.g., due to the first ionization potential (FIP-effect) [2]. This is of importance to deduce solar abundances of noble gases and other elements from SW data. Solar, i.e., photospheric, abundances of noble gases are indirectly determined due to the lack of suitable lines in the spectrum. Recently, solar abundance estimates for Ne and Ar were strongly reduced whereas Kr and Xe changed only slightly [3]. This led to a dramatic decrease of the solar Ar/Kr ratio by a factor of ~3 from the earlier value [4] of 2140. If true, this change would invalidate theories of heavy noble gas fractionation in the SW identified with regolith data [1, 5]. The Kr and Xe composition in present-day SW will enable us to reassess solar abundances and fractionation theories. Thus, we concentrate here on abundances of Ar, Kr and Xe in the bulk SW

Neutral interstellar helium parameters based on IBEX-Lo observations and test particle calculations

Neutral Interstellar Helium (NISHe) is almost unaffected at the heliospheric interface with the interstellar medium and freely enters the solar system. It provides some of the best information on the characteristics of the interstellar gas in the Local Interstellar Cloud. The Interstellar Boundary Explorer (IBEX) is the second mission to directly detect NISHe. We present a comparison between recent IBEX NISHe observations and simulations carried out using a well-tested quantitative simulation code. Simulation and observation results compare well for times when measured fluxes are dominated by NISHe (and contributions from other species are small). Differences between simulations and observations indicate a previously undetected secondary population of neutral helium, likely produced by interaction of interstellar helium with plasma in the outer heliosheath. Interstellar neutral parameters are statistically different from previous in situ results obtained mostly from the GAS/Ulysses experiment, but they do agree with the local interstellar flow vector obtained from studies of interstellar absorption: the newly-established flow direction is ecliptic longitude 79.2 deg, latitude -5.1 deg, the velocity is \sim 22.8 km/s, and the temperature is 6200 K. These new results imply a markedly lower absolute velocity of the gas and thus significantly lower dynamic pressure on the boundaries of the heliosphere and different orientation of the Hydrogen Deflection Plane compared to prior results from Ulysses. A different orientation of this plane also suggests a new geometry of the interstellar magnetic field and the lower dynamic pressure calls for a compensation by other components of the pressure balance, most likely a higher density of interstellar plasma and strength of interstellar magnetic field.Comment: Data from IBEX-Lo on Interstellar Boundary Explorer analyzed; 40 pages, 24 figures, 2 table

Frequent Cross-Species Transmission of Parvoviruses among Diverse Carnivore Hosts

Although parvoviruses are commonly described in domestic carnivores, little is known about their biodiversity in nondomestic species. A phylogenetic analysis of VP2 gene sequences from puma, coyote, gray wolf, bobcat, raccoon, and striped skunk revealed two major groups related to either feline panleukopenia virus (“FPV-like”) or canine parvovirus (“CPV-like”). Crossspecies transmission was commonplace, with multiple introductions into each host species but, with the exception of raccoons, relatively little evidence for onward transmission in nondomestic species