Visual binary orbits and masses POST HIPPARCOS The parallaxes from Hipparcos are an important ingredient to derive moreaccurate masses for known orbital binaries, but in order to exploit theparallaxes fully, the orbital elements have to be known to similarprecision. The present work gives improved orbital elements for some 205systems by combining the Hipparcos astrometry with existing ground-basedobservations. The new solutions avoid the linearity constraints andomissions in the Hipparcos Catalog by using the intermediate TransitData which can be combined with ground-based observations in arbitarilycomplex orbital models. The new orbital elements and parallaxes give newmass-sum values together with realistic total error-estimates. To getindividual masses at least for main-sequence systems, the mass-ratioshave been generally estimated from theoretical isochrones and observedmagnitude-differences. For some 25 short-period systems, however, trueastrometric mass-ratios have been determined through the observedorbital curvature in the 3-year Hipparcos observation interval. Thefinal result is an observed `mass-luminosity relation' which falls closeto theoretical expectation, but with `outliers' due to undetectedmultiplicity or to composition- and age-effects in the nonuniformnear-star sample. Based in part on observations collected with the ESAHipparcos astrometry satellite. Tables~ 1, 3, 4 and 6 are also availablein electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr~(130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
Binary star speckle measurements during 1989-1993 from the SAO 6 M and 1 M telescopes in Zelenchuk We have continued to survey visual and interferometric binary stars withsignificant orbital motion by means of speckle method at the telescopesof the Special Astrophysical Observatory (SAO) in Zelenchuk. Here wepresent the lists of 267 speckle observations made with the 6 m and the1 m telescopes in the period May 1989-November 1993.
