Results 1 to 10 of about 31,041 (165)
The History of Astrometry [PDF]
The European Physical Journal H, 2012 The history of astrometry, the branch of astronomy dealing with the positions of celestial objects, is a lengthy and complex chronicle, having its origins in the earliest records of astronomical observations more than two thousand years ago, and ...
Perryman, Michael
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The Future of Astrometry in Space [PDF]
Frontiers in Astronomy and Space Sciences, 2018 This contribution focuses on the importance of astrometry and on its future developments. Over the centuries astrometry has greatly contributed to the advance of the knowledge of the Universe. Nowadays a major breakthrough is on the way due to astrometric sky surveys from space. ESA space missions Hipparcos first and then Gaia point out the outstanding
A Vallenari
exaly +5 more sources
Astrometry of circumstellar masers [PDF]
, 2002 The circumstellar masers around evolved stars offer an interesting possibility to measure stellar parameters through VLBI astrometry. In this paper the application of this technique is discussed, including the accuracy and the uncertainties of the method.
A Eckart +6 more
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Radio astrometry with chromatic AGN core positions
Astronomy and Astrophysics, 2009 Aims: The effect of frequency-dependent AGN core positions (``core-shifts'') on radio Very Long Baseline Interferometry (VLBI) global astrometry measurements is investigated.
R W Porcas
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Flowdown of the TMT astrometry error budget(s) to the IRIS design [PDF]
, 2016 TMT has defined the accuracy to be achieved for both absolute and differential astrometry in its top-level requirements documents. Because of the complexities of different types of astrometric observations, these requirements cannot be used to specify ...
Andersen, David +11 more
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Astrometry in the Future [PDF]
CELESTIAL MECHANICS AND DYNAMICAL ASTRONOMY, 1997 AbstractThe introduction of the extragalactic reference frame and the availability of the Hipparcos and Tycho catalogs will have major impacts on changing the accuracy levels of astrometry in the future.There is a need for accurate densification of the reference frames down to at least 20thmagnitude.
openaire +1 more source
Reference-less detection, astrometry, and photometry of faint companions with adaptive optics [PDF]
, 2009 We propose a complete framework for the detection, astrometry, and photometry of faint companions from a sequence of adaptive optics corrected short exposures. The algorithms exploit the difference in statistics between the on-axis and off-axis intensity.
Beuzit +19 more
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Relativity in Astrometry [PDF]
Symposium - International Astronomical Union, 1986 The coordinate dependence of the definition of light deflexion is discussed and the concepts of “natural” and “proper” reference frame are introduced in order to derive astrometric observables from coordinate quantities. Confusion in published formulations of VLBI data analysis is discussed in the context of the IAU definition of the coordinate time ...
openaire +1 more source
Gaia: The Astrometry Revolution [PDF]
, 2015 The power of micro-arcsecond ($\mu$as) astrometry is about to be unleashed. ESA's Gaia mission, now headed towards the end of the first year of routine science operations, will soon fulfil its promise for revolutionary science in countless aspects of ...
Bonavita, M. +4 more
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Orbital Parameter Determination for Wide Stellar Binary Systems in the Age of Gaia
, 2020 The orbits of binary stars and planets, particularly eccentricities and inclinations, encode the angular momentum within these systems. Within stellar multiple systems, the magnitude and (mis)alignment of angular momentum vectors among stars, disks, and ...
Dupuy, Trent J. +6 more
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