1 Lipovka A.A.
2 Lipovka N.M.

Universidad de Sonora



In present work, the optical identifications of radio sources in the vicinity of a bright star (the sixth brightest star in the constellation Cygnus) zet Cyg are carried out. Within suggested identifications the coordinates of the radio sources coincided with high precision with those for a group of stars.Within the standard for NVSS identification method in which the association of the celestial objects in radio with those in optics is carried out, none of the radio source is not identified with optical object in the area under investigation. For example the bright star zet Cyg (1m) fell in this case into an empty field in the radio and in the nearest neighborhood of it (6') no radio source above the threshold sensitivity of the review NVSS was detected. However, using our method of identification of the optical and radio sky (LKL), in the study area in the vicinity of the star zet Cyg, 8 radio sources of the total 9 bright stars, were identified successfully. The radio source ICRF J211529.4 + 293338 is listed in radio catalogue ICRF2 as the reference object, and normally is identified in the NVSS with quasar which has redshift z = 1.514. However, the size of this «quasar» is two minutes of arc (at the diagram of the radio telescope θ = 45'') and covers an area of sky in the optical plate, in which more than 20 quasi-stellar objects are located that at least cause uncertainty and doubt on the correctness of suggested identification. Moreover, when the ICRF J211529.4 + 293338 was identified with a star zet Cyg by using the LKL method, at the same time other 7 stars coincided with radio objects located in the immediate vicinity of zet Cyg. Our optical identifications also confirmed the presence of the radio refraction in the interstellar medium. In this case, radio refraction in the interstellar medium consists rr (RA) = 8 s in right ascension, and rr (DEC) = 24'' in declination for near and more distant stars in the vicinity of the star zet Cyg.
1.   Lipovka A. A., Lipovka N. M. Patent na izobretenie № 2010107938/28(011185). Sposob privyazki koordinat nebesnyh radioistochnikov k opticheskoj astrometricheskoj sisteme koordinat LKL (anl. LKL). 2011,
2.   Lipovka A. A., Lipovka N. M. Radioizluchenie skopleniya galaktik A1716 i gruppy zvezd. Astrofizika, 2013, Vol. 56, 2. pp. 241–250.
3.   Lipovka A.A., Lipovka N.M. (2013) Problems of connection of radio sky to optical sky. History and perspective. Geodezia i Kartografia, (10), pp. 2-7.
4.   Lipovka A.A., Lipovka N.M. (2014) On the problem of the optical identifications of the radio sky and optical sky in vicinity of the cumulation NGC2232. Geodezia i Kartografia, (7), pp. 10-13. (In Russian). DOI: 10.22389/0016-7126-2014-889-7-10-13.
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6.   DSS. URL: http://cadcwww.dao.nrc.ca/cadcbin/
7.   ICRF. URL: http://www.gao.spb.ru/english/as/ac_vlbi/sou_car.dat
8.   The NRAO VLA Sky Survey. URL: http://www.cv.nrao.edu/NVSS/
9.   UCAC. URL: vizier.u-strasbg.fr/viz-bin/VisieR
10.   Verkhodanov O.V., Trushkin S.A., Andernach H., Chernenkov V.N. http://www.sao.ru/cats/.
Lipovka A.A., 
Lipovka N.M., 
(2016) On the problem of the reference coordinate system quasars (ICRF2) and about the radioemission from the stars located near zet Cyg. Geodesy and cartography = Geodezia i Kartografia, (4), pp. 2–6. (In Russian). DOI: 10.22389/0016-7126-2016-910-4-2-6
Publication History
Received: 19.10.2015
Accepted: 18.12.2015
Published: 20.05.2016



2016 April DOI: