1,556 research outputs found
Analogs of Martian eolian features in southwestern Egypt
Emphasis was placed on the morphology and patterns of streaks in the Uweinat region, the relationship of topography to streak patterns, and correlation of field and laboratory studies of the desert surface sediments with color and tonal variations seen from orbit. The research objectives were to provide the necessary groundtruth information on terrestrial eolian features in order to properly interpret the orbital data and to use the interpretations as a basis for investigation of Martian eolian features
Earth observations and photography experiment: Summary of significant results
Observation and photographic data from the Apollo Soyuz Test Project are analyzed. The discussion is structured according to the fields of investigation including: geology, desert studies, oceanography, hydrology, and meteorology. The data were obtained by: (1) visual observations of selected Earth features, (2) hand-held camera photography to document observations, and (3) stereo mapping photography of areas of significant scientific interest
Lunar igneous intrusions
Lunar igneous intrusions revealed from Apollo 10 and 11 flight photograph
On a conjecture of Dekking : The sum of digits of even numbers
Let and denote by the sum-of-digits function in base . For
consider # \{0 \le n < N : \;\;s_q(2n) \equiv j \pmod q \}.
In 1983, F. M. Dekking conjectured that this quantity is greater than
and, respectively, less than for infinitely many , thereby claiming an
absence of a drift (or Newman) phenomenon. In this paper we prove his
conjecture.Comment: 6 pages, accepted by JTN
Effective equidistribution of primitive rational points on expanding horospheres
We prove an effective version of a result due to Einsiedler, Mozes, Shah and
Shapira who established the equidistribution of primitive rational points on
expanding horospheres in the space of unimodular lattices in at least
dimensions. Their proof uses techniques from homogeneous dynamics and relies in
particular on measure-classification theorems --- an approach which does not
lend itself to effective bounds. We implement a strategy based on spectral
theory, Fourier analysis and Weil's bound for Kloosterman sums in order to
quantify the rate of equidistribution for a specific horospherical subgroup in
any dimension. We apply our result to provide a rate of convergence to the
limiting distribution for the appropriately rescaled diameters of random
circulant graphs.Comment: 21 pages, incorporates the referee's comments and correction
Morphologic studies of the Moon and planets
The impact, volcanic, and tectonic history of the Moon and planets were investigated over an eight year period. Research on the following topics is discussed: lunar craters, lunar basins, lunar volcanoes, correlation of Apollo geochemical data, lunar geology, Mars desert landforms, and Mars impact basins
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