Search Publications
An Astrometric Catalogue of Radio Stars
Walter, H. G.; Hering, R.; de Vegt, Ch.
The first part is presented of a radio star catalog encompassing 186 objects whose selection was guided by the priority criteria of the Hipparchos Input Catalogue Consortium. Since these criteria are well suited to the need for linkage of ground-based optical systems to radio reference frames, this first selection is also considered a suitable bas…
Optical Variability of Extragalactic Objects Used to Tie the HIPPARCOS Reference Frame to an Extragalactic System Using Hubble Space Telescope Observations
Bozyan, Elizabeth P.; Hemenway, Paul D.; Argue, A. Noel
Observations of a set of 89 extragalactic objects (EGOs) will be made with the Hubble Space Telescope Fine Guidance Sensors and Planetary Camera in order to link the HIPPARCOS Instrumental System to an extragalactic coordinate system. Most of the sources chosen for observation contain compact radio sources and stellarlike nuclei; 65% are optical v…
VLBI and Optical Astrometry of Southern Extragalactic Radio Sources and Radio Stars
White, Graeme L.; Jauncey, David L.; Lestrade, Jean-Francois +3 more
Mark III very long baseline interferometry (VLBI) has been used to determine the positions of ten compact extragalactic radio sources in the southern hemisphere. These positions are relative to the Jet Propulsion Laboratory VLBI celestial reference frame and are accurate at the 0.01" level, more than an order of magnitude improvement compared to t…
CCD astrometry of visual binaries. II. Differential measurements of northern double stars.
Sinachopoulos, D.; Seggewiss, W.
Separations and position angles of 148 visual multiple systems were measured by means of a CCD detector attached to the Calar Alto 1.23-m telescope. The program stars are candidates for the Hipparcos Input Catalog.
Mesures de vitesses radiales. IV. Accompagnement AU sol du programme d'observation du satellite Hipparcos.
Duflot, M.; Genty, V.; Mannone, C. +1 more
The paper presents 396 radial velocities of stars distributed in 19 fields of 4 x 4 degrees. The study employs the Fehrenbach objective prism method and the same measuring technique used in a previous paper (Fehrenbach et al., 1987).
Mesures de vitesses radiales. III. Accompagnement AU sol du programmed'observation du satellite Hipparcos. Mesure de la vitesse radiale de391 etoiles dans 12 champs.
Burnage, R.; Fehrenbach, Ch.
The radial velocities of 391 stars, obtained with the Fehrenbach objective prism associated to the Schmidt telescope of the Observatoire de Haute-Provence are presented. These stars belong to fields specially chosen for containing several Hipparcos input catalog star members. Each field is presented independently. The list includes HD and BD ident…
UBVRI photometry of G, K, M HIPPARCOS stars.
Jordi, C.; Figueras, F.; Torra, J. +1 more
UBVRI data are presented for a set of 229 late-type stars, most of them being high proper motion stars. All these data are part of the Input Catalog planned observations for the Hipparcos mission.
Ephemerides of the 48 HIPPARCOS minor planets for the year 1991
Bec-Borsenberger, A.
To be observed by Hipparcos, the position of each object has to be known with an accuracy of 1 arcsecond and its magnitude with an accuracy of 0.5 mag. Therefore, the orbital elements of 48 selected minor planets of the Hipparcos mission, have been improved in order to extrapolate their ephemerides with the accuracy required. These ephemerides for…
The Problem of the HIPPARCOS Reference Frame
Lattanzi, M. G.; Bucciarelli, B.; Bernacca, P. L.
The basic principles of the realization of a fundamental optical reference frame by using space platforms are outlined in the light of the first of such astrometry projects, i.e., the HIPPARCOS mission of the European Space Agency. The available adaptations of these principles, expected to lead to a HIPPARCOS catalog of more than 100,000 star posi…
Optical positions of radiostars. II.
Costa, E.; Loyola, P.
Precise optical positions, relative to either the Perth 70 or the AGK3R catalogs, have been obtained for 40 radiostars proposed to the Hipparcos observing list. Precision levels between 0.18 and 0.29 arcsecs were obtained.