Forum Springer Astron. Astrophys.
Forum Whats New Search Orders

Astron. Astrophys. 359, 1201-1204 (2000)

Table of Contents
Available formats: HTML | PDF | (gzipped) PostScript

Research Note

Spatial variability of compact extragalactic radiosources

M. Feissel 1,2, A.-M. Gontier 1 and T.M. Eubanks 3

1 Observatoire de Paris/CNRS UMR8630, 61 av. de l'Observatoire, 75014 Paris, France
2 Institut Géographique National/LAREG, 8 Av. Blaise Pascal, Champs sur Marne, 77455 Marne la Vallée Cedex 2, France
3 US Naval Observatory, Washington, DC 20392, USA

Received 6 April 2000 / Accepted 18 May 2000


Several hundreds of compact extragalactic radiosources (mainly quasars, but also BL Lac and galaxies) are monitored in a series of permanent VLBI geodetic and astrometric programs that were initiated in the late 1970's in support to the solar system exploration, for studying the Earth's rotation and crustal deformations, and for creating the celestial reference frame later recommended by the IAU as the International Celestial Reference Frame (ICRF). Time series of directions of ICRF objects can be established at a sub-milliarcsecond precision level. A subset of 16 objects with a dense observational history over 1988-1999 are studied in order to derive information on the geometric and statistical properties of their emission at centimetric wavelength.

Key words: astrometry – reference systems – galaxies: quasars: general

Send offprint requests to: M. Feissel (feissel@ensg.ign.fr)

© European Southern Observatory (ESO) 2000

Online publication: July 13, 2000