Measurements of Visual Double Stars Orbit
Satrio Fatkhusalma, Taufieq Zannata Ramadha, Hakim Al-Ikhsan, Muhammad Harits Al-Akbar, Fatimah Zahra

Bosscha Observatory
Astronomy Study Program, ITB

Abstract

Visual binary stars (commonly are called as double stars) are stellar pairs whose it^s component can be resolved through telescopic imaging. Study of these kind objects is fundamental topic in astronomy, due to it^s role as direct method for determining the most important properties of stellar physics, i.e. it^s mass. High-precision astrometric and photometric measurements which are obtained via CCD imaging, combined with data provided by Washington Double Star Catalog (WDS) enable us to calculate the orbit accurately. In this work, we report the result of double stars observations in 2025 using 8 inch (20 cm) Schmidt-Cassegrain telescope at Bosscha Observatory, Lembang. Observed objects were selected from WDS catalog. We carried position angle and separation angle calculation based on data we obtained from our observation using photutils.centroids in python mainly using 2 degree Gaussian and center of mass fitting function. Based on available WDS data and our data, we prioritize objects with \theta \leq 10 10 over the epoch from the first observation to 2025 to further calculate the orbit of each of these pairs. Throughout 2025, 182 binaries were selected and observed. Data points are fitted with least-square method, then we configurate the orbit using Danby^s Newton-Raphson for Kepler^s equation solution, thus we obtained the result presented here.

Keywords: Visual double stars, Astrometric observation, Orbital fitting

Topic: Stellar Physics