Statistical Effects from Hipparcos Astrometry
نویسندگان
چکیده
منابع مشابه
Photocentre displacement of minor planets: analysis of Hipparcos astrometry
We present a study of the phase effect (or photocentre offset) on the astrometry of minor planets. Analysis of the high precision Hipparcos observations of the largest asteroids shows the validity of the model. Minor planets Ceres, Pallas, Vesta and Iris show a brightness distribution close to the lunar scattering properties, while Juno and Hebe are found to be more uniformly bright objects. Fo...
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We present absolute trigonometric parallaxes and relative proper motions for three members of the Pleiades star cluster, obtained with HST’s Fine Guidance Sensor 1r, a white-light interferometer. We estimate spectral types and luminosity classes of the stars comprising the astrometric reference frame from R ≈ 2, 000 spectra, VJHK photometry, and reduced proper motions. From these we derive esti...
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The analysis of planetary satellites or asteroids ground based observations is quite similar. Our first goal was to improve the astrometric reduction for digitized photographic plates in case of too few reference stars and to propose solutions. We here present astrometric techniques used for old observations of the Galilean satellites made with the 26-inch refractor of USNO in Washington DC fro...
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During its 39-month mission, Hipparcos observed the star HD 209458 on 89 occasions. Five of these observations are shown to correspond to epochs of planetary transits, with a 2.3 ± 0.4% mean decrease of flux in the Hp band being observed during the transits. As a result of the long temporal baseline of more than 8 years between the Hipparcos and radial velocity measurements, an accurate orbital...
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ژورنال
عنوان ژورنال: Highlights of Astronomy
سال: 2002
ISSN: 1539-2996
DOI: 10.1017/s153929960001460x