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Modern Photographic Catalogue Work - Aspects of Observing Techniques and Reduction Methods
de Vegt, Chr.
The consequent application of present optical technology for the construction of substantially improved instrumentation in photographic astrometry and the application of rigorous reduction techniques provide all means for the construction of new, global position catalogs with a precision of a few 0.01 arcsec. At the same time the limiting magnitud…
Objectives of ground-based astrometry after HIPPARCOS
Kovalevsky, J.
After a short summary of the results expected from the HIPPARCOS mission, the author gives several examples illustrating the needs that will arise afterwards in order to maintain the level of precision achieved and to extend it to many more objects. Three domains are particularly dealt with in this paper:The maintenance of the HIPPARCOS reference …
An early TYCHO astrometric catalogue
Bastian, U.; Hog, E.; Egret, D. +2 more
The TICR catalogue is arevision of TIC, theTYCHO Input Catalogue, and will contain positions derived from the first 12 months of TYCHO observations. Its properties, its role in TYCHO data analysis, and other possible uses are discussed. Since TICR will list about 500 000 stars with a positional precision of 0."15 (rms) and since it should become a…
Astrometry of Southern Radio Sources
Preston, Robert A.; White, Graeme L.; Gulkis, Samuel +7 more
An overview is presented of a number of astrometry and astrophysics programs based on radio sources from the Parkes 2.7 GHz catalogues. The programs cover the optical identification and spectroscopy of flat-spectrum Parkes sources and the determination of their milliarc-second radio structures and positions. Work is also in progress to tie togethe…
An Observational Program for a Unified Optical / Radio Reference Frame
White, G.; de Vegt, C.; Johnston, K. J. +4 more
An observational pilot program is described which provides a first step towards the construction of an inertial extragalactic reference frame from optical and radio measurements. Candidate objects will be selected from extragalactic compact radio sources which display optical counterparts. Galactic radio stars will be secondary reference objects. …
The HIPPARCOS Input Catalogue - a Progress Report from an Astrometric Point of View
Turon, C.; Requieme, Y.
The construction of the Hipparcos satellite is proceeding according to the schedule and should be finished in March 1988. But, due to some problems with the Ariane European booster, the launch has now been postponed until 1989. In practice, this means that the astronomical community may expect delivery of the final Hipparcos Catalog only in 1995. …
Le nouvel astrolabe de l'Observatoire de Paris
Chollet, F.
The new polyvalent astrolabe of the Paris Observatory is described. After some optical modifications this new instrument is able to observe the stars, some planets, and the sun with an internal error less than 0.4 arcsec in the last case. Some new modifications are in progress to obtain better results and stability in the solar observations. This …
Residuals for the Observations of the 62 Selected Minor Planets
Calaf, J.
This paper reports results of the improvement of orbital elements of the 62 minor planets included in the Hipparcos mission. The astrometric observations supplied by the Minor Planet Center and the meridian circles at La Palma and Bordeaux observatories were used by the author. The accuracy reached (RMS O-C) for each minor planet and for La Palma …