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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The rapid progress of atomic and nuclear physics in the twentieth century altered the way scientific results are documented, preserved and disseminated. Boris Pritychenko discusses how atomic and nuclear data tables have become a central resource for the community.
An in-progress investigation aimed at characterizing the X-ray luminosity of very faint QSOs is described. More than 100 faint, previously uncataloged QSOs which lie in areas imaged in X rays at very high sensitivity were discovered.
Contents include the following: mission description and system identification; environment description; system architectural description; system security requirements; organization and resources; and ditscap plan. Appendix A, acronym list. Appendix B, definitions. Appendix C, references.
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A NASA/USDA funded program offers satellite-derived products for lakes, reservoirs, river reaches, and wetland zones. These are currently being derived from the 10-day and monthly-resolution radar altimeter series. However, observational parameters from the laser based ICESat-2 mission, and the enhanced SWOT KaRIn instrument will also be integrated to meet various end user requirements. The resulting measurements will ultimately be a combination of surface water level and slope, surface water extent, water storage and basin bathymetry, plus a suite of Status Indicators which highlight deviations from long-term and seasonal averages. The main stakeholders are the USDA/Foreign Agricultural Service, the US Geological Survey, USACE/NGA, and various Wetland-related organizations. Applications centre on water and energy resources and fish-catch potential, and on natural hazards (floods and droughts). There is a demand for a global monitoring service, but primary focus is on regions where gauge measurement access is restricted or delayed, or where gauge deployment is hazardous. Ongoing surface acquisition checks and feedback to CNES focusses on the success or failure of the on-board DEM’s on a case-by-case basis. Multiple projects are also underway to improve the surface elevations measurements and the along track resolution (minimum water body width) via exploration of the high resolution (Doppler) Range estimates, the FF-SAR technique, and the high- resolution radiometer based wet tropospheric correction. And while Level3+4 surface water products are being directed by end user requirements, the overriding NASA objectives are the formation of high quality Earth Data Records with high accuracy and uniformity across multiple decades.
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The Kepler spacecraft has collected data of high photometric precision and cadence almost continuously since operations began on 2009 May 2. Primarily designed to detect planetary transits and asteroseismological signals from solar-like stars, Kepler has provided high quality data for many areas of investigation. Unconditioned simple aperture time-series photometry are however affected by systematic structure. Examples of these systematics are differential velocity aberration, thermal gradients across the spacecraft, and pointing variations. While exhibiting some impact on Kepler's primary science, these systematics can critically handicap potentially ground-breaking scientific gains in other astrophysical areas, especially over long timescales greater than 10 days. As the data archive grows to provide light curves for 10(exp 5) stars of many years in length, Kepler will only fulfill its broad potential for stellar astrophysics if these systematics are understood and mitigated. Post-launch developments in the Kepler archive, data reduction pipeline and open source data analysis software have occurred to remove or reduce systematic artifacts. This paper provides a conceptual primer for users of the Kepler data archive to understand and recognize systematic artifacts within light curves and some methods for their removal. Specific examples of artifact mitigation are provided using data available within the archive. Through the methods defined here, the Kepler community will find a road map to maximizing the quality and employment of the Kepler legacy archive.