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Full-Text Articles in Physical Sciences and Mathematics
Measurements Of Geomagnetic Declination (1685-1910) Using Land Surveys, Lidar, And Stone Walls, John W. Delano Phd
Measurements Of Geomagnetic Declination (1685-1910) Using Land Surveys, Lidar, And Stone Walls, John W. Delano Phd
Atmospheric and Environmental Science Faculty Scholarship
Nearly 1200 kilometers of boundaries surveyed in 1685-1910, upon which stone walls were subsequently built, were measured using high-resolution LiDAR (Light Detection and Ranging) in the northeastern United States (New Hampshire and New York). The geomagnetic declinations at the time of the original land surveys of those stone wall-defined boundaries have been determined and compared with (i) current geophysical models (i.e., gufm1, IGRF12; United States Historical Declinations-USHD), and (ii) measured declinations (Bauer, 1902). With the exception of lower declinations (i.e., 1.5° eastward) in 1775-1810, the results of this study are in good agreement with gufm1 and IGRF12 geomagnetic declinations. This …
40ar/39ar Ages Of Lunar Impact Glasses: Relationships Among Ar Diffusivity, Chemical Composition, Shape, And Size, John W. Delano Phd, Nicolle Zellner
40ar/39ar Ages Of Lunar Impact Glasses: Relationships Among Ar Diffusivity, Chemical Composition, Shape, And Size, John W. Delano Phd, Nicolle Zellner
Atmospheric and Environmental Science Faculty Scholarship
Lunar impact glasses, which are quenched melts produced during cratering events on the Moon, have the potential to providenot only compositional information about both the local and regional geology of the Moon but also information about the impact flux over time. We present in this paper the results of 73 new 40Ar/39Ar analyses of well-characterized, inclusion-free lunar impact glasses and demonstrate that size, shape, chemical composition, fraction of radiogenic 40Ar retained, and cosmic ray exposure (CRE) ages are important for 40Ar/39Ar investigations of these samples. Specifically, analyses of lunar impact glasses from the Apollo 14, 16, and 17 landing sites …
Search For Life, John W. Delano Phd
Search For Life, John W. Delano Phd
Atmospheric and Environmental Science Faculty Scholarship
NASA's Astrobiology program seeks to determine the origin and distribution of life in the Milky Way galaxy using scientific expertise from many disciplines (e.g., astronomy, biochemistry, geochemistry). This presentation, which provides an overview of the progress that has been made in this effort, was delivered on 23 June 2015 at the Green Mountain Academy for Lifelong Learning in Manchester, VT. With NASA's development of the Space Launch System (SLS), vigorous multi-disciplinary scientific research, and additional spacecraft (e.g., TESS) for finding and analyzing planets orbiting other stars, exciting discoveries will continue.