Dynamical investigation of the multiple star ADS 9173 AB

TL;DR

This study investigates the complex multiple star system ADS 9173 AB, analyzing its long-term orbital dynamics and astrometric data to understand its structure and the observed residual wave patterns.

Contribution

The paper provides a detailed dynamical analysis of ADS 9173 AB, including the calculation of its orbit and the astrometric orbit of component B using long-term observations.

Findings

Orbit period of AB pair is approximately 6306 years.

Astrometric orbit of component B aligns with spectroscopic data.

Residuals show a wave pattern with a 20-year period.

Abstract

Star ADS 9173=WDS 14135+5147=Hip 69483 is a complex system. The B component has a spectroscopic companion, whose orbit with a period of 4.9 years has been known since 1986. The Gaia telescope has detected a distant faint pair over 100 arcsec away from the bright AB pair. In our article, we study the movement in a bright pair based on long-term observations with the 26-inch refractor of the Pulkovo Observatory. The AB pair orbit with a period of 6306 years was calculated using the apparent motion parameters (AMP) method. The astrometric orbit of the component B was determined on the basis of the residuals of the homogeneous CCD observations up to 2023 with the 26-inch refractor. It is in agreement with the spectroscopic one. The remaining secondary residuals show a wave with a period of approximately 20 years, the reasons for which are discussed.