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[en] For the twenty-fifth consecutive year, a NASA/ASEE Summer Faculty Fellowship Program was conducted at the Marshall Space Flight Center (MSFC). The basic objectives of the programs are: (1) to further the professional knowledge of qualified engineering and science faculty members; (2) to stimulate an exchange of ideas between participants and NASA; (3) to enrich and refresh the research and teaching activities of the participants' institutions; and (4) to contribute to the research objectives of the NASA Centers. The Faculty Fellows spent ten weeks at MSFC engaged in a research project compatible with their interests and background and worked in collaboration with a NASA/MSFC colleague
[en] This report includes an overview of some ways to go wrong in making decisions – Common deficiencies in reasoning and in modeling, thinking clearly about uncertainty, Case Studies: 1: NASA Challenger 2: Davis-Besse vessel-head event, Interlude: Critical Thinking 3: NASA Columbia 4: Fukushima and concluding thoughts.
[en] We present the properties of galaxies in filaments around the Virgo cluster with respect to their vertical distance from the filament spine using the NASA–Sloan Atlas catalog. The filaments are mainly composed of low-mass, blue dwarf galaxies. We observe that the g − r color of galaxies becomes blue and stellar mass decreases with increasing vertical filament distance. The galaxies were divided into higher-mass () and lower-mass () subsamples. We also examine the distributions of g − r color, stellar mass, Hα equivalent width (EW(Hα)), near-ultraviolet (NUV) − r color, and H i fraction of the two subsamples with the vertical distance. The lower-mass galaxies exhibit a negative g − r color gradient, whereas higher-mass galaxies have a flat g − r color distribution. We observe a negative EW(Hα) gradient for higher-mass galaxies, whereas lower-mass galaxies show no distinct EW(Hα) variation. In contrast, the NUV − r color distribution of higher-mass galaxies shows no strong trend, whereas the lower-mass galaxies show a negative NUV − r color gradient. We do not see clear gradients of H i fraction in either the higher- or lower-mass subsample. We propose that the negative color and stellar mass gradients of galaxies can be explained by mass assembly from past galaxy mergers at different vertical filament distances. In addition, galaxy interactions might be responsible for the contrasting features of EW(Hα) and NUV − r color distributions between the higher- and lower-mass subsamples. The distributions of H i fraction of the two subsamples suggest that the processes of ram pressure stripping and gas accretion may be ignored in the Virgo filaments.
[en] The US cosmic-ray research program has four facets. Theese are: the in-situ deep-space measurements, the solar and galactic measurements conducted from Earth-orbiting spacecraft, the heavy-nuclei and high-energy measurements from balloons, and the greater than 1016 eV air-shower measurements
[en] The author describes work involving NASA's Gamma Ray Observatory (GRO). GRO exemplifies the near zero principle because it investigates new gamma ray phenomena by relying on the space program to take us into the region of zero interference above the earth's atmosphere. In its present form GRO has four experiments
[en] This paper describes a probabilistic method which extends classical PRA to include some characteristics of the organization that processes or manages an engineering system. Ataxonomy of errors is presented and their organizational roots are examined. An assembly model is proposed for the analysis of the resulting spectrum of capacities of the system. The management of the Thermal Protection system of the Space Shuttle is used as an illustration. The model allows assessment of the benefits of organizational improvements of the orbiter's processing
[en] During the summer of 2006, students at the Center for Space Nuclear Research sought to augment the current NASA lunar exploration architecture with a nuclear thermal rocket (NTR). An additional study investigated the possible use of an NTR with existing launch vehicles to provide 21 metric tons of supplies to the lunar surface in support of a lunar outpost. Current cost estimates show that the complete mission cost for an NTR-enhanced assembly of Delta-IV and Atlas V vehicles may cost 47-86% more than the estimated Ares V launch cost of $1.5B; however, development costs for the current NASA architecture have not been assessed. The additional cost of coordinating the rendezvous of four to six launch vehicles with an in-orbit assembly facility also needs more thorough analysis and review. Future trends in launch vehicle use will also significantly impact the results from this comparison. The utility of multiple launch vehicles allows for the development of a more robust and lower risk exploration architecture
[en] Despite their apparently very different objectives, astrophysics - the study of the largest structures in the Universe - and particle physics - the study of the smallest - have always had common ground. On 23 February 1987 a supernova explosion provided additional impetus to reinforce these links. In this article, David Schramm of the University of Chicago and the NASA/Fermilab Astrophysics Center, explains why
[en] From its unique vantage point 900 kilometres above the earth's surface, NASA's Cosmic Background Explorer (COBE) satellite has a privileged view of cosmic background radiation - the remnants of the early (radiation-dominated) Universe which followed the Big Bang some ten Gigayears ago, and possibly some subsequent history. In this way astroparticle physicists get a first peek at the quantum cosmology which moulded the infant Universe