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Efficient Credit Assignment through Evaluation Function Decomposition

Evolutionary methods are powerful tools in discovering solutions for difficult continuous tasks. When such a solution is encoded over multiple genes, a genetic algorithm faces the difficult credit assignment problem of evaluating how a single gene in a chromosome contributes to the full solution. Typically a single evaluation function is used for the entire chromosome, implicitly giving each gene in the chromosome the same evaluation. This method is inefficient because a gene will get credit for the contribution of all the other genes as well. Accurately measuring the fitness of individual genes in such a large search space requires many trials. This paper instead proposes turning this single complex search problem into a multi-agent search problem, where each agent has the simpler task of discovering a suitable gene. Gene-specific evaluation functions can then be created that have better theoretical properties than a single evaluation function over all genes. This method is tested in the difficult double-pole balancing problem, showing that agents using gene-specific evaluation functions can create a successful control policy in 20 percent fewer trials than the best existing genetic algorithms. The method is extended to more distributed problems, achieving 95 percent performance gains over tradition methods in the multi-rover domain.

Agogino, Adrian↗

Enabling the Discovery of Recurring Anomalies in Aerospace System Problem Reports using High-Dimensional Clustering Techniques

This paper describes the results of a significant research and development effort conducted at NASA Ames Research Center to develop new text mining techniques to discover anomalies in free-text reports regarding system health and safety of two aerospace systems. We discuss two problems of significant importance in the aviation industry. The first problem is that of automatic anomaly discovery about an aerospace system through the analysis of tens of thousands of free-text problem reports that are written about the system. The second problem that we address is that of automatic discovery of recurring anomalies, i.e., anomalies that may be described m different ways by different authors, at varying times and under varying conditions, but that are truly about the same part of the system. The intent of recurring anomaly identification is to determine project or system weakness or high-risk issues. The discovery of recurring anomalies is a key goal in building safe, reliable, and cost-effective aerospace systems. We address the anomaly discovery problem on thousands of free-text reports using two strategies: (1) as an unsupervised learning problem where an algorithm takes free-text reports as input and automatically groups them into different bins, where each bin corresponds to a different unknown anomaly category; and (2) as a supervised learning problem where the algorithm classifies the free-text reports into one of a number of known anomaly categories. We then discuss the application of these methods to the problem of discovering recurring anomalies. In fact the special nature of recurring anomalies (very small cluster sizes) requires incorporating new methods and measures to enhance the original approach for anomaly detection. ?& pant 0-

Srivastava, Ashok, N.↗

Extraterrestrial Life

Extraterrestrial Intelligence is intelligent life that developed somewhere other than the earth. Such life has not yet been discovered. However, scientific research, including astronomy, biology, planetary science and studies of fossils here on earth have led many scientists to conclude that such life may exist on planets orbiting at least some of the hundreds of billions of stars in our Milky Way Galaxy. Today, some researchers are trying to find evidence for extraterrestrial intelligence. This effort is often called SETI, which stands for Search for Extraterrestrial Intelligence. SETI researchers decided that looking for evidence of their technology might be the best way to discover other intelligent life in the Galaxy. They decided to use large radio telescopes to search the sky over a wide range of radio frequencies...

Klein, M. J.↗

A Web 2.0 and OGC Standards Enabled Sensor Web Architecture for Global Earth Observing System of Systems

This paper will describe the progress of a 3 year research award from the NASA Earth Science Technology Office (ESTO) that began October 1, 2006, in response to a NASA Announcement of Research Opportunity on the topic of sensor webs. The key goal of this research is to prototype an interoperable sensor architecture that will enable interoperability between a heterogeneous set of space-based, Unmanned Aerial System (UAS)-based and ground based sensors. Among the key capabilities being pursued is the ability to automatically discover and task the sensors via the Internet and to automatically discover and assemble the necessary science processing algorithms into workflows in order to transform the sensor data into valuable science products. Our first set of sensor web demonstrations will prototype science products useful in managing wildfires and will use such assets as the Earth Observing 1 spacecraft, managed out of NASA/GSFC, a UASbased instrument, managed out of Ames and some automated ground weather stations, managed by the Forest Service. Also, we are collaborating with some of the other ESTO awardees to expand this demonstration and create synergy between our research efforts. Finally, we are making use of Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) suite of standards and some Web 2.0 capabilities to Beverage emerging technologies and standards. This research will demonstrate and validate a path for rapid, low cost sensor integration, which is not tied to a particular system, and thus be able to absorb new assets in an easily evolvable, coordinated manner. This in turn will help to facilitate the United States contribution to the Global Earth Observation System of Systems (GEOSS), as agreed by the U.S. and 60 other countries at the third Earth Observation Summit held in February of 2005.

Mandl, Daniel↗

Are Fullerenes Relevant to Cosmochemistry? A New Finding

The abundances of noble gases found in primitive, carbonaceous meteorites are unexpected when compared with our Sun. Known as Q-gases (Q for some unknown carrier dubbed quintessence ), this anomaly has remained a mystery since it was discovered in 1975. Q-gases are characterized by increasing depletions with decreasing atomic number (Z) relative to solar noble gases and normalized to 132Xe (Figure 1). This Q-gas mass fractionation is unexplained, and its investigation is important to understanding the origin of the solar system. However, the subject is fraught with controversy, in part due to the complex nature of Q and in part due to claims of some researchers that cannot be reproduced by other investigators. The topic is discussed in numerous places [e.g., 1-4], with models of Q falling into two basic categories, both involving carbon entrapment of noble gases. First (Group A), there is the conservative two-dimensional view that Q-gases are adsorbed or sorbed onto a "labyrinth" of graphite or carbon grains [5-9], or they undergo active capture onto growing surfaces [6]. Second (Group B), there is the view holding to the remarkable property of carbon discovered in 1985. Carbon can curl up into closed geometries of hexagon- and pentagon-shaped carbon-ring configurations, a property ignored completely by Group A. Group B thinks of Q as a three-dimensional structure of endohedral carbon cages like fullerenes, carbon onions, or some class of carbon nanotubes [3, 4, 10]. Group B does not exclude Group A effects.

Wilson, T. L.↗

Swift Multi-wavelength Observing Campaigns: Strategies and Outcomes

The Swift gamma-ray burst explorer has been operating since December 2004 as both a gamma-ray burst (GRB) monitor and telescope and a multi-wavelength observatory, covering the energy range from V band and near UV to hard X rays above 150 keV. It is designed to rapidly repoint to observe newly discovered GRBs, and this maneuverability, combined with an easily changed observing program, allows Swift to also be an effective multiwavelength observatory for non-GRB targets, both as targets of opportunity and pre-planned multi-wavelength observing campaigns. Blazars are particularly attractive targets for coordinated campaigns with TeV experiments since many blazars are bright in both the hard X-ray and TeV energy ranges. Successful coordinated campaigns have included observations of 3C454.3 during its 2005 outburst. The latest Swift funding cycles allow for non- GRB related observations to be proposed. The Burst Alert Telescope on Swift also serves as a hard X-ray monitor with a public web page that includes light curves for over 400 X-ray sources and is used to alert the astronomical community about increased activity from both known and newly discovered sources. This presentation mill include Swift capabilities, strategies and policies for coordinated multi-wavelength observations as well as discussion of the potential outcomes of such campaigns.

Krimm, Hans A.↗

Spectroscopic Confirmation of a Massive Red-sequence Selected Galaxy Cluster at Z=1.34 in the SpARCS-South Cluster Survey

The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a z'-passband imaging survey, consisting of deep (z' approx. 24 AB) observations made from both hemispheres using the CFHT 3.6m and CTIO 4m telescopes. The survey was designed with the primary aim of detecting galaxy clusters at z > 1. In tandem with pre-existing 3.6 micron observations from the Spitzer Space Telescope SWIRE Legacy Survey, SpARCS detects clusters using an infrared adaptation of the two-filter red-sequence cluster technique. The total effective area of the SpARCS cluster survey is 41.9 sq deg. In this paper, we provide an overview of the 13.6 sq deg Southern CTIO/MOSAICII observations. The 28.3 sq deg Northern CFHT/MegaCam observations are summarized in a companion paper by Muzzin et al. (2008a). In this paper, we also report spectroscopic confirmation of SpARCS J003550-431224, a very rich galaxy cluster at z = 1.335, discovered in the ELAIS-S1 field. To date, this is the highest spectroscopically confirmed redshift for a galaxy cluster discovered using the red-sequence technique. Based on nine confirmed members, SpARCS J003550-431224 has a preliminary velocity dispersion of 1050+/-230 km/s. With its proven capability for efficient cluster detection, SpARCS is a demonstration that we have entered an era of large, homogeneously-selected z > 1 cluster surveys.

Wilson, Gillian↗

Polymer Coats Leads on Implantable Medical Device

Langley Research Center s Soluble Imide (LaRC-SI) was discovered by accident. While researching resins and adhesives for advanced composites for high-speed aircraft, Robert Bryant, a Langley engineer, noticed that one of the polymers he was working with did not behave as predicted. After putting the compound through a two-stage controlled chemical reaction, expecting it to precipitate as a powder after the second stage, he was surprised to see that the compound remained soluble. This novel characteristic ended up making this polymer a very significant finding, eventually leading Bryant and his team to win several NASA technology awards, and an "R&D 100" award. The unique feature of this compound is the way that it lends itself to easy processing. Most polyimides (members of a group of remarkably strong and incredibly heat- and chemical-resistant polymers) require complex curing cycles before they are usable. LaRC-SI remains soluble in its final form, so no further chemical processing is required to produce final materials, like thin films and varnishes. Since producing LaRC-SI does not require complex manufacturing techniques, it has been processed into useful forms for a variety of applications, including mechanical parts, magnetic components, ceramics, adhesives, composites, flexible circuits, multilayer printed circuits, and coatings on fiber optics, wires, and metals. Bryant s team was, at the time, heavily involved with the aircraft polymer project and could not afford to further develop the polymer resin. Believing it was worth further exploration, though, he developed a plan for funding development and submitted it to Langley s chief scientist, who endorsed the experimentation. Bryant then left the high-speed civil transport project to develop LaRC-SI. The result is an extremely tough, lightweight thermoplastic that is not only solvent-resistant, but also has the ability to withstand temperature ranges from cryogenic levels to above 200 C. The thermoplastic s unique characteristics lend it to many commercial applications; uses that Bryant believed would ultimately benefit industry and the Nation. "LaRC-SI," he explains, "is a product created in a government laboratory, funded with money from the tax-paying public. What we discovered helps further the economic competitiveness of the United States, and it was our goal to initiate the technology transfer process to ensure that our work benefited the widest range of people." Several NASA centers, including Langley, have explored methods for using LaRC-SI in a number of applications from radiation shielding and as an adhesive to uses involving replacement of conventional rigid circuit boards. In the commercial realm, LaRC-SI can now be found in several commercial products, including the thin-layer composite unimorph ferroelectric driver and sensor (THUNDER) piezoelectric actuator, another "R&D 100" award winner (Spinoff 2005).

Source record↗

The International Space Station and the Space Debris Environment: 10 Years On

For just over a decade the International Space Station (ISS), the most heavily protected vehicle in Earth orbit, has weathered the space debris environment well. Numerous hypervelocity impact features on the surface of ISS caused by small orbital debris and meteoroids have been observed. In addition to typical impacts seen on the large solar arrays, craters have been discovered on windows, hand rails, thermal blankets, radiators, and even a visiting logistics module. None of these impacts have resulted in any degradation of the operation or mission of the ISS. Validating the rate of small particle impacts on the ISS as predicted by space debris environment models is extremely complex. First, the ISS has been an evolving structure, from its original 20 metric tons to nearly 300 metric tons (excluding logistics vehicles) ten years later. Hence, the anticipated space debris impact rate has grown with the increasing size of ISS. Secondly, a comprehensive visual or photographic examination of the complete exterior of ISS has never been accomplished. In fact, most impact features have been discovered serendipitously. Further complications include the estimation of the size of an impacting particle without knowing its mass, velocity, and angle of impact and the effect of shadowing by some ISS components. Inadvertently and deliberately, the ISS has also been the source of space debris. The U.S. Space Surveillance Network officially cataloged 65 debris from ISS from November 1998 to November 2008: from lost cameras, sockets, and tool bags to intentionally discarded equipment and an old space suit. Fortunately, the majority of these objects fall back to Earth quickly with an average orbital lifetime of less than two months and a maximum orbital lifetime of a little more than 15 months. The cumulative total number of debris object-years is almost exactly 10, the equivalent of one piece of debris remaining in orbit for 10 years. An unknown number of debris too small to be tracked and cataloged have also been generated, but normally with even shorter orbital lifetimes. Finally, eight collision avoidance maneuvers have been performed to avoid potential collisions between ISS and large, tracked space debris. The most recent such maneuver was accomplished by ESA's Automated Transfer Vehicle, the Jules Verne, just three months before the 10th anniversary of the launch of ISS's first element.

Johnson, Nicholas↗

Evolution of Web Services in EOSDIS: Search and Order Metadata Registry (ECHO)

During 2005 through 2008, NASA defined and implemented a major evolutionary change in it Earth Observing system Data and Information System (EOSDIS) to modernize its capabilities. This implementation was based on a vision for 2015 developed during 2005. The EOSDIS 2015 Vision emphasizes increased end-to-end data system efficiency and operability; increased data usability; improved support for end users; and decreased operations costs. One key feature of the Evolution plan was achieving higher operational maturity (ingest, reconciliation, search and order, performance, error handling) for the NASA s Earth Observing System Clearinghouse (ECHO). The ECHO system is an operational metadata registry through which the scientific community can easily discover and exchange NASA's Earth science data and services. ECHO contains metadata for 2,726 data collections comprising over 87 million individual data granules and 34 million browse images, consisting of NASA s EOSDIS Data Centers and the United States Geological Survey's Landsat Project holdings. ECHO is a middleware component based on a Service Oriented Architecture (SOA). The system is comprised of a set of infrastructure services that enable the fundamental SOA functions: publish, discover, and access Earth science resources. It also provides additional services such as user management, data access control, and order management. The ECHO system has a data registry and a services registry. The data registry enables organizations to publish EOS and other Earth-science related data holdings to a common metadata model. These holdings are described through metadata in terms of datasets (types of data) and granules (specific data items of those types). ECHO also supports browse images, which provide a visual representation of the data. The published metadata can be mapped to and from existing standards (e.g., FGDC, ISO 19115). With ECHO, users can find the metadata stored in the data registry and then access the data either directly online or through a brokered order to the data archive organization. ECHO stores metadata from a variety of science disciplines and domains, including Climate Variability and Change, Carbon Cycle and Ecosystems, Earth Surface and Interior, Atmospheric Composition, Weather, and Water and Energy Cycle. ECHO also has a services registry for community-developed search services and data services. ECHO provides a platform for the publication, discovery, understanding and access to NASA s Earth Observation resources (data, service and clients). In their native state, these data, service and client resources are not necessarily targeted for use beyond their original mission. However, with the proper interoperability mechanisms, users of these resources can expand their value, by accessing, combining and applying them in unforeseen ways.

Mitchell, Andrew↗

Photometric Studies of GEO Orbital Debris

The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the Cerro Tololo Inter- American Observatory (CTIO) 0.9-m for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R=15th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? More than 90 calibrated sequences of R-B-V-I-R magnitudes for a sample of 50 objects have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus the B-R color is a true measure of the surface of the debris piece facing the telescopes for that observation. Any change in color reflects a real change in the debris surface. We will compare our observations with models and laboratory measurements of selected surfaces.

Seitzer, Patrick↗

Photometric Studies of GEO Debris

The photometric signature of a debris object can be useful in determining what the physical characteristics of a piece of debris are. We report on optical observations in multiple filters of debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan's 0.6-m aperture Schmidt telescope MODEST (for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the SMARTS (Small and Medium Aperture Research Telescope System) 0.9-m at CTIO for orbits and photometry. Our goal is to determine 6 parameter orbits and measure colors for all objects fainter than R = 15 th magnitude that are discovered in the MODEST survey. At this magnitude the distribution of observed angular rates changes significantly from that of brighter objects. There are two objectives: 1. Estimate the orbital distribution of objects selected on the basis of two observational criteria: brightness (magnitude) and angular rates. 2. Obtain magnitudes and colors in standard astronomical filters (BVRI) for comparison with reflectance spectra of likely spacecraft materials. What is the faint debris likely to be? In this paper we report on the photometric results. For a sample of 50 objects, more than 90 calibrated sequences of R-B-V-I-R magnitudes have been obtained with the CTIO 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could be that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO 0.9-m observes in B, and MODEST in R. The CCD cameras are electronically linked together so that the start time and duration of observations are the same to better than 50 milliseconds. Thus the B-R color is a true measure of the surface of the debris piece facing the telescopes for that observation. Any change in color reflects a real change in the debris surface.

Seitzer, Patrick↗

Fossil Microorganisms and Formation of Early Precambrian Weathering Profiles

Weathering crusts are the only reliable evidences of the existence of continental conditions. Often they are the only source of information about exogenous processes and subsequently about conditions under which the development of the biosphere occurred. A complex of diverse fossil microorganisms was discovered as a result of Scanning Electron Microscope investigations. The chemical composition of the discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, the microorganisms fixed in rocks played the role of catalyst. The decomposition of minerals comprising the rocks and their transformation into clayey (argillaceous) minerals, most likely occurred under the influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.

Rozanov, A. Yu↗

Panel Discussion: Life in the Cosmos

Water appears to be essential to all life on Earth. For this reason, "Follow the Water" has been adopted as a mantra for the search for Life in the Cosmos. Expeditions have helped to establish the limits and biodiversity of life in the most extreme environments on Earth. Microbial extremophiles inhabit acidic streams; hypersaline and hyperalkaline lakes and pools; the cold deep sea floor, permafrost, rocks, glaciers, and perennially ice-covered lakes of the polar environments; geysers, volcanic fumaroles, hydrothermal vents and hot rocks deep within the Earth's crust. The ESA Venus Express Spacecraft entered Venusian Orbit in 2006 and continues to produce exciting results. The Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument made the first detection of hydroxyl in the atmosphere of Venus, indicating it is much more similar to Earth and Mars than previously thought. Huge hurricane-like vortices have been found above the poles of the planet and as yet unidentified UV absorbers that form mysterious dark bands in the upper atmosphere. At 70 km and below, water vapor and sulfur dioxide combine to form sulfuric acid droplets that create a haze above the cloud tops. Thermophilic acidophiles, such as have recently been discovered on Earth, could possibly survive in the hot sulfuric acid droplets that exist in the upper atmosphere of Venus. In order to understand how to search for life elsewhere in the Solar System, over 40 VIRTIS images of Earth from Venus have been obtained to search for evidence of life on Earth. The signatures of water and molecular Oxygen were detected in the Earth s atmosphere, but the atmosphere of Venus also exhibits these signatures. The water and water ice are far more abundant on comet, the polar caps and permafrost of Mars and the icy moons of Jupiter and Saturn. These "frozen worlds" of our Solar System, are much more promising regimes where extant or extinct microbial life may exist. The ESA Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) probe has found that both the North and South Polar Caps of Mars are approximately 3.5 km thick and are composed almost entirely of water ice. In winter, a thin dry ice layer covers the caps, but it sublimates directly to CO2 in the spring. The ESA Mars Express Orbiter images reveal Rupes Tenuis to be a vast snow-laden region on the southern edge of the Martian North Polar Cap. The Mars Exploration Rover Spirit found alkaline volcanic rocks in the Gusev Crater and the Phoenix Mars Lander has shown that the soil of Mars is much more alkaline than previously expected. The Phoenix Mars Lander has also made direct observations of frozen and liquid water on Mars. It is known that microorganisms from Alaska, Siberia and Antarctica can remain alive frozen in permafrost or ice for long periods of time. These discoveries increase the possibility that the Labeled Release Experiment may have discovered life on Mars during the Viking Mission and provide strong impetus for the return of life detection experiments to Mars. Changes in the spin rate of Saturn's moon Titan indicate that it may also harbor a 300 km thick liquid water ocean beneath its icy crust. The NASA/ESA/Italian Space Agency Cassini Spacecraft has imaged geysers containing water vapor, methane, carbon dioxide and organics erupting from the "tiger stripe" regions near the South Pole of Saturn's moon Enceladus. The high temperatures observed, the water vapor and large number of ice particles expelled suggest that a liquid water lake may exist beneath the "tiger stripe" ice cracks of Enceladus. The NASA Deep Impact probe found the surface temperature of comet 9P/Temple 1 at 1.5 AY was slightly above the ice/water phase change temperature (273 K). This suggests melting of water ice near the comet surface. A spectrometer the spacecraft detected a mixture of clay and carbonate minerals (that form in the presence of liquid water) streaming off the comet after the collision with the pactor. The study of chemical and mineral biomarkers, chiral amino acids and possible indigenous microfossils in SNC and carbonaceous meteorites continues. These results suggest that comets should be considered prime targets in the search for Life in the Cosmos. The ESA Rosetta mission is on track to rendezvous with comet 67P/Churyumov-Gerasimenko. The recent space observations combined with new information about the ability of microbial extremophiles to thrive in polar environments suggest that life may be far more widely distributed in the Cosmos than previously thought possible. The Panelists will review recent discoveries and provide their own insights about Life in the Cosmos -- followed by a question and answer session with the audience.

Hoover, Richard B.↗

Magnetar Observations with Fermi/GBM

NASA's Fermi Observatory was launched June 11, 2009; the Fermi Gamma Ray Burst Monitor (GBM) began normal operations on July 14, about a month after launch, when the trigger algorithms were enabled. In the first year of operations we recorded emission from four magnetar sources; of these, only one was an old magnetar: SGR 1806+20. The other three detections were: SGR J0501+4516, newly discovered with Swift and extensively monitored with both Swift and GBM, SGR J1550-5418, a source originally classified as an Anomalous X-ray Pulsar (AXP) and a very recently discovered new source, SGR 0418+5729. I report below on the current status of the analyses efforts of the GBM data.

Kouveliotou, Chryssa↗

NASA's Earth Observing Data and Information System

NASA's Earth Observing System Data and Information System (EOSDIS) has been a central component of NASA Earth observation program for over 10 years. It is one of the largest civilian science information system in the US, performing ingest, archive and distribution of over 3 terabytes of data per day much of which is from NASA s flagship missions Terra, Aqua and Aura. The system supports a variety of science disciplines including polar processes, land cover change, radiation budget, and most especially global climate change. The EOSDIS data centers, collocated with centers of science discipline expertise, archive and distribute standard data products produced by science investigator-led processing systems. Key to the success of EOSDIS is the concept of core versus community requirements. EOSDIS supports a core set of services to meet specific NASA needs and relies on community-developed services to meet specific user needs. EOSDIS offers a metadata registry, ECHO (Earth Observing System Clearinghouse), through which the scientific community can easily discover and exchange NASA s Earth science data and services. Users can search, manage, and access the contents of ECHO s registries (data and services) through user-developed and community-tailored interfaces or clients. The ECHO framework has become the primary access point for cross-Data Center search-and-order of EOSDIS and other Earth Science data holdings archived at the EOSDIS data centers. ECHO s Warehouse Inventory Search Tool (WIST) is the primary web-based client for discovering and ordering cross-discipline data from the EOSDIS data centers. The architecture of the EOSDIS provides a platform for the publication, discovery, understanding and access to NASA s Earth Observation resources and allows for easy integration of new datasets. The EOSDIS also has developed several methods for incorporating socioeconomic data into its data collection. Over the years, we have developed several methods for determining needs of the user community including use of the American Customer Satisfaction Index and a broad metrics program.

Mitchell, Andrew E.↗

Influences of the Driver and Ambient Medium Characteristics on the Formation of Shocks in the Solar Atmosphere

Traveling interplanetary (IP) shocks were discovered in the early 1960s, but their solar origin has been controversial. Early research focused on solar flares as the source of the shocks, but when coronal mass ejections (CMEs) were discovered, it became clear that fast CMEs clearly can drive the shocks. Type II radio bursts are excellent signatures of shocks near the Sun. The close correspondence between type II radio bursts and solar energetic particles (SEPs) makes it clear that the same shock accelerates ions and electrons. A recent investigation involving a large number of IP shocks revealed that about 35% of IP shocks do not produce type II bursts or SEPs. Comparing these radio quiet (RQ) shocks with the radio loud (RL) ones revealed some interesting results: (1) there is no evidence for blast waves, in that all IP shocks can be attributed to CMEs, (2) a small fraction (20%) of RQ shocks is associated with ion enhancements at the shocks when they move past the observing spacecraft, (3) the primary difference between the RQ and RL shocks can be traced to the different kinematic properties of the associated CMEs and the variation of the characteristic speeds of the ambient medium, and (4) the shock properties measured at 1 AU are not too different for the RQ and RL cases due to the interaction of the shock driver with the IP medium that seems to erase the difference.

Nat, Gopalswamy↗

The Infrared-Optical Telescope (IRT) of the Exist Observatory

The IRT is a 1.1m visible and infrared passively cooled telescope, which can locate, identify and obtain spectra of GRB afterglows at redshifts up to z 20. It will also acquire optical-IR, imaging and spectroscopy of AGN and transients discovered by the EXIST (The Energetic X-ray Imaging Survey Telescope). The IRT imaging and spectroscopic capabilities cover a broad spectral range from 0.32.2m in four bands. The identical fields of view in the four instrument bands are each split in three subfields: imaging, objective prism slitless for the field and objective prism single object slit low resolution spectroscopy, and high resolution long slit on single object. This allows the instrument, to do simultaneous broadband photometry or spectroscopy of the same object over the full spectral range, thus greatly improving the efficiency of the observatory and its detection limits. A prompt follow up (within three minutes) of the transient discovered by the EXIST makes IRT a unique tool for detection and study of these events, which is particularly valuable at wavelengths unavailable to the ground based observatories.

Kutyrev, Alexander↗