2011.03369
Asteroid resource utilization: ethical concerns and progress
Rivkin, et al
As asteroid mining moves toward reality, the high bar to entering the business may limit participation and increase inequality, reducing or eliminating any benefit gained by marginalized people or developing nations. Consideration of ethical issues is urgently needed, as well as participation in international, not merely multilateral, solutions.
2011.03407
Dark Energy Survey Year 3 Results: Photometric Data Set for Cosmology
Sevilla-Narbe, et al
2011.03408
Dark Energy Survey Year 3 Results: Weak Lensing Shape Catalogue
Gatti, et al
2011.03409
Dark Energy Survey Year 3 Results: Point-spread function modeling
Jarvis, Bernstein, et al
We introduce a new software package for modeling the point-spread function (PSF) of astronomical images, called Piff (PSFs In the Full FOV), which we apply to the first three years (known as Y3) of the Dark Energy Survey (DES) data. We describe the relevant details about the algorithms used by Piff to model the PSF, including how the PSF model varies across the field of view (FOV). Diagnostic results show that the systematic errors from the PSF modeling are very small over the range of scales that are important for the DES Y3 weak lensing analysis. In particular, the systematic errors from the PSF modeling are significantly smaller than the corresponding results from the DES year one (Y1) analysis. We also briefly describe some planned improvements to Piff that we expect to further reduce the modeling errors in future analyses.
2011.03410
Dark Energy Survey internal consistency tests of the joint cosmological probes analysis with posterior predictive distributions
Doux, et al
2011.03411
Dark Energy Survey Year 3 Results: Optimizing the lens sample in combined galaxy clustering and galaxy-galaxy lensing analysis
Porredon, et al
2011.03985
The Earths long-term climate changes and ice ages: a derivation of Milankovitch cycles from first principles
Rainey
Long-term changes in the tilt of the Earths axis, relative to the plane of its orbit, are of great significance to long-term climate change, because they control the size of the arctic and antarctic circles. These Milankovitch cycles have generally been calculated by numerical integration of Newtons equations of motion, and there is controversy over the results because they are sensitive to numerical drift over the very long computer simulations involved. In this paper the cycles are calculated from first principles, without any reliance on computer simulation. The problem is one of planetary precession, and is solvable by the methods used to study the precession of a spinning top. It is shown that the main component of Milankovitch cycles has a period of 41,000 years and is due to one of the modes of precession of the Earth-Venus system. The other mode of this system produces a component of period 29,500 years, and a third component of period 54,000 years results from the influence of the precession of the orbits of Jupiter and Saturn. These results agree closely with several of the numerical simulations in the literature, and strongly suggest that other different results in the literature are wrong.
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