The Pulkovo Programme for the Study of Visual Double Stars

Abstract

The observation of visual double stars at Pulkovo is a traditional work of Pulkovo astronomers started by W. Struve in 1830 at Dorpat (now Tartu). After the Second World War and restoration of the observatory in 1960, the observations of double stars have been carried out with help of 26-inch Zeiss refractor using the photographic technique. We observe the visual binaries which satisfy the conditions of highest accuracy of astrometric reduction: d > 3′, m < 12.0, dm < 1.0, δ>20°.

The supermassive black hole at the center of our galaxy: Determination of its main physical parameters

“…In this time, the star passed through three quarters of its apparent ellipse around Sgr A*-the compact radio source at the Galactic center believed to coincide with the SMBH. We applied the AMP method [28][29][30][31][32][33] to determine the orbit of S2 based on a short arc. The aim of our present study is to test how well it is possible to derive this orbit by applying the AMP method to an inhomogeneous series of observations, and to compare the results for this method with those for methods based on the complete orbital ellipse.…”

“…The latter method was initially developed by a group of researchers at the Main Astronomical Observatory of the Russian Academy of Sciences for studies of the orbits of artificial satellites, but later found wide application to the orbits of binary stars [28][29][30][31][32][33]. The modern AMP method (as applied to binaries) is based on the use of a high-precision, fairly dense series of the relative positions, trigonometric parallaxes, and relative radial-velocities of the binary components for an epoch close to the mean epoch for the astrometric observations.…”