The Extragalactic Optical-Radio Reference Frame
نویسندگان
چکیده
منابع مشابه
Determination of optical positions for 23 extragalactic radio sources
AB S TRACT The optical counterparts of 23 extragalactic radio sources, of which 13 are in the southern hemisphere, have been observed by three telescopes equipped with CCDs. By reference to the Astrographic/Tycho (ACT) Reference, Carlsberg Meridian (CMC), Positions and Proper Motions (PPM), Hipparcos (HIP) and Lick Northern Proper Motion (NPM) catalogues, the positions of the 23 objects have be...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1995
ISSN: 0074-1809
DOI: 10.1017/s0074180900227940