Results 21 to 30 of about 4,904 (168)
Bound Orbits and Epicyclic Motions around Renormalization Group Improved Schwarzschild Black Holes
We study timelike particles’ bound orbits around renormalization group improved Schwarzschild black holes (RGISBHs), which originate from renormalization group improvement of the Einstein–Hilbert action by using the running Newton constant.
Hou-Yu Lin, Xue-Mei Deng
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VERA’s 20 yr Evolution in Science and Technology
We review the past 20 yr evolution of VERA (VLBI Exploration of Radio Astrometry) in both science and techinology. VERA is a VLBI array in Japan which consists of four 20 m-diameter telescopes, originally dedicated to phase-referencing VLBI astrometry ...
Mareki Honma +3 more
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ABSTRACT Isochrones, equal‐age curves, are widely used in astrophysics to estimate stellar ages. Classical stellar parameters are, however, very limited in their usability for main sequence stars because of their weak age‐dependence. Here, rotation period measurements provide complementary information.
David Gruner, Sydney A. Barnes
wiley +1 more source
Technological and scientific developments during the past century made a new branch of astronomy flourish, i.e. astrophysics, and resulted in our present deep understanding of the whole Universe.
Høg E.
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Connecting VLBI and Gaia celestial reference frames
The current state of the link problem between radio and optical celestial reference frames is considered.The main objectives of the investigations in this direction during the next few years are the preparation of a comparisonand the mutual orientation ...
Zinovy Malkin
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Uncertainties in Historic Visual Double Star Measures—III Accurate Calibration Pairs
ABSTRACT Based on space‐based positions and proper motions, we present accurate rectilinear elements for 857 double star pairs over the celestial sphere. These elements allow for the computation of precision ephemeris Position Angles and Separations of these pairs.
Roderick R. Letchford, Graeme L. White
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Introduction: In recent decades, numerous large survey projects have been initiated to enhance our understanding of the cosmos. Among these, the Vera C.
Yuanyu Hong +7 more
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RESULTS OF PROCESSING OF ASTRONEGATIVES WITH COMMERCIAL SCANNER
Astrometric errors depending on the method of scanning with different spatial resolutions were studied with commercial scanner such as Epson Perfection V750 Pro.
Yu. I. Protsyuk +3 more
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Satellites and Small Bodies With ALMA: Insights Into Solar System Formation and Evolution
Abstract Our understanding of the formation and evolution of planetary systems has made major advances in the past decade. This progress has been driven in large part by the Atacama Large Millimeter/submillimeter Array (ALMA), which has given us an unprecedented view of solar system bodies themselves, and of the structure and chemistry of forming ...
Katherine de Kleer +3 more
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Since the advent of Gaia catalog, positional precision of a ground-based telescope can be greatly improved by correction of more subtle errors, including positional biases induced by atmospheric turbulence, and some instrumental factors such as geometric
Z. J. Zheng +3 more
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