Results 1 to 10 of about 38,863 (241)
Microarcsecond Radio Astrometry [PDF]
Annual Review of Astronomy and Astrophysics, 2014 Astrometry provides the foundation for astrophysics. Accurate positions are required for the association of sources detected at different times or wavelengths, and distances are essential to estimate the size, luminosity, mass, and ages of most objects.
Reid, M. J., Honma, M.
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VERA’s 20 yr Evolution in Science and Technology
GalaxiesWe 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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Open Astronomy, 2011 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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The Astronomical JournalSince 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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Frontiers in Astronomy and Space SciencesIntroduction: 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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Connecting VLBI and Gaia celestial reference frames
Frontiers in Astronomy and Space Sciences, 2016 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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Precise Dynamical Masses of Directly Imaged Companions from Relative Astrometry, Radial Velocities, and Hipparcos–Gaia DR2 Accelerations [PDF]
Astronomical Journal, 2018 We measure dynamical masses for five objects—three ultracool dwarfs, one low-mass star, and one white dwarf—by fitting orbits to a combination of the Hipparcos–Gaia Catalog of Accelerations, literature radial velocities, and relative astrometry.
Timothy D. Brandt, T. Dupuy, B. Bowler
semanticscholar +1 more source
RESULTS OF PROCESSING OF ASTRONEGATIVES WITH COMMERCIAL SCANNER
Odessa Astronomical Publications, 2014 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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Comparison of Gaia DR2 Parallaxes of Stars with VLBI Astrometry [PDF]
Astrophysical Journal, 2019 We compare the parallaxes of stars from VLBI astrometry in the literature to those in the Gaia DR2 catalog. Our full sample contains young stellar objects, evolved AGB stars, pulsars, and other radio stars.
S. Xu 徐 +4 more
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Odessa Astronomical Publications, 2014 The paper discusses and illustrates the steps of basic processing of digitized image of astro negatives. Software for obtaining of a rectangular coordinates and photometric values of objects on photographic plates was created in the environment ...
Yu. I. Protsyuk +2 more
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