"The results of the digitization of the Pulkovo Observatory astronegative archive”
by Dr. Maxim Khovrichev from Pulkovo Observatory
Thursday 27 October 2022 at 11h
Paviljoen, Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels
ABSTRACT:
There are a lot of astronomical applications for the digitization of old astronomical photographic plates. This technique may be used for the analysis and understanding of a wide set of long-term phenomena like the dynamical evolution of planetary satellite systems, asteroid populations, binary and multiple stars. The Pulkovo archive contains more than 50000 astronegatives. There is no distortion-free digitizer with a tenths micrometer accuracy level at the Pulkovo observatory. Our solution is the usage of the NAROO (Paris Observatory) scans of the template astronegatives for calibration and distortion elimination of the astronegatives scanned with the Pulkovo MDD-digitizer. This technique allows us to achieve an accuracy of about 1 𝞵m using MDD-digitizer. It is enough for a number of applications. As a result, more than 6000 celestial positions of the main Saturnian satellites in the Gaia system have been determined for the period 1972 - 2007 with an accuracy of 50 mas. The 10 mas level trends in (O-C) have been revealed. An analysis of the relative motion of the ADS 9346 components based on digitized plates and CCD observations led us to the discovery of the low-mass companion orbiting around the A-component of the binary system (about 0.1-0.2 solar masses). Our discovery has been confirmed by recent spectrometric observations of this star taken with the SAO RAS 6-m telescope.
