Search Publications
Independent Analysis of µδ Data of ILS and INDLS Catalogs to Obtain the Spin of the Bright Gaia DR2 Reference Frame
Aleksić, J.; Damljanović, G.; Stojanović, M.
The Gaia DR2 reference frame should be without relative rotation to the quasars (QSOs) and consistent with the International Celestial Reference System (ICRS). For the faint part of DR2 (stars with Gaia magnitude G≥16) that task was done via Gaia's observations of QSOs (G≥17 mag), but the bright DR2 (G≤13 mag) is difficult to validate and it rotat…
Corrected mu_delta for Stars of Hipparcos Catalogue from Independent Latitude Observations over Many Decades
Damljanovic, G.; Milic, I. S.
During the last century, there were many so-called independent latitude (IL) stations with the observations which were included into data of a few international organizations (like Bureau International de l'Heure - BIH, International Polar Motion Service - IPMS) and the Earth rotation programmes for determining the Earth Orientation Parameters - E…
On the Component Masses of Visual Binaries
Cvetkovic, Z.; Ninkovic, S.
In the Sixth Catalog of Orbits of Visual Binary Stars we found those belonging to the Main Sequence to form a sample containing 432 visual binaries. Their total masses were obtained dynamically, i.e. they were calculated using the orbital elements and the new Hipparcos parallaxes. For the same pairs the total mass was also found astrophysically - …
Corrections to the Hipparcos Proper Motions in Declination for 807 Stars
Damljanovic, G.; Pejovic, N.
We used the data on latitude variations obtained from observations with 10 classical photographic zenith tubes (PZT) in order to improve the Hipparcos proper motions in declinations µ_{δ} for 807 stars. Part of observing programmes, carried out during the last century for the purpose of studying the Earth's rotation, were realized by using P…
On the Mass Distribution of Stars in the Solar Neighbourhood
Ninkovic, S.; Trajkovska, V.
The present authors analyse samples consisting of Hipparcos stars. Based on the corresponding HR diagrams they estimate masses of Main-Sequence stars from their visual magnitudes. They find that already beyond the heliocentric radius of 10 pc the effects of observational selection against K and M dwarfs become rather strong. For this reason the au…
Improvement of Hipparcos Proper Motions in Declination
Damljanovic, G.; Pejovic, N.; Jovanovic, B.
More than a decade elapsed after the HIPPARCOS ESA mission (ESA 1997) observations have been collected. This first astronomical satellite mission was less than 4 years long so that 1991.25 is the epoch of the HIPPARCOS Catalogue. Many other projects have checked or improved HIPPARCOS data. Also, a long series of ground - based optical observations…
Corrections of Proper Motions in Declination By Using ILS Data
Damljanovic, G.; Pejovic, N.
There are nowadays numerous astrometric ground--based observations of some stars referred to Hipparcos Catalogue, made at many observatories during the last century. We used the data on latitude variations, covering the period 1899.7 -- 1979.0, of visual Zenith Telescopes (ZT) of International Latitude Service (ILS), to improve the Hipparcos prope…
Photographic Zenith Tubes Observations to Improve HIPPARCOS Proper Motion in Declination of Some Stars
Damljanovic, G.
A procedure of calculation and results of an attempt to improve proper motions in declination for some HIPPARCOS stars are presented. A long series of optical observations of these stars observed with Photographic Zenith Tubes (PZT) are used. The HIPPARCOS ESA mission (ESA 1997) was nearly 4 years long, but each of the different Earth rotation pro…
Astrometric Star Catalogues as Combination of Hipparcos/Tycho Catalogues with Ground-Based Observations
Vondrak, J.
The successful ESA mission Hipparcos provided very precise parallaxes, positions and proper motions of many stars in optical wavelength. Therefore, it is a primary representation of International Celestial Reference System in this wavelength. However, the shortness of the mission (less than four years) causes some problems with proper motions of t…
Dynamics of quadruple system Finsen 332 = ADS 11640 = Hip 92027 = WDS
Olevic, D.; Cvetkovic, Z.
In 1829 Struve discovered a double star denoted as STF 2375 AB later on. Its separation was 2.2". It was noticed by Finsen from the Southern Observatory (Johannesburg) in 1953 that the components A and B are close binaries with separations about 0.15. The motion within this quadruple system - FIN 332 Aa and FIN 332 Bb - has been monitored from tha…