Articles

Kepler’s Constant and WDS Orbit

 Suryadi Siregar* and Rihandian Nedya Pratama

 Bosscha Observatory and Astronomy Research Division, Institut Teknologi Bandung, Indonesia 

Email*:suryadi@as.itb.ac.id

 Abstract

The aim of this work are to find a Kepler’s constant by using polynomial regression of the angular separation  r=r (t) and the position angle q=q(t). The Kepler’s constant obtained are used to derive the element of orbit. As a case study the angular separation and the position angle of the WDS 00063 +5826 and the WDS 04403-5857 were investigates. For calculating the element of orbit the Thiele-Innes van den Bos method are used. The rough data of the angular separation r(t) and the position angle q(t) are taken from the US Naval Observatory, Washington. This work also presents the masses and absolute bolometric magnitudes of eachstar. These stars include into the main-sequence stars with the spectral class G5V for WDS 04403-5857 and the type of spectrum G3V for WDS 00063 +5826. The life time of the primary star and the secondary star of WDS 04403-5857 nearly equal to 2×1010 years. Otherwise the life time of the primary star and the secondary star of WDS 00063+5826 are 2×1010 years and 1.9×1010 years respectively.

 Keywords:Visual Binary Orbit-Method of the Thiele Innes van den Bos-Two Body Problem

view article

Recalculating the orbit of Alpha Centauri AB(*)

S. Siregar and H. Kuncarayakti
Astronomy Group and Bosscha Observatory
Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology,Bandung
e-mail:suryadi@as.itb.ac.id

Abstract

The two main components of the closest star system, a Centauri AB (RA 14h39m, Dec -60o50’, J2000.0) is indubitably one of the most studied visual double stars. This paper presents the results of our recalculation of orbital and physical parameters of this system using Thiele – van den Bos method, based on observational data from year 1900 to 2002.

Keywords: Visual double stars- Orbit calculation

Abstrak

Dua komponen utama bintang terdekat a Centauri AB (RA 14h39m, Dec -60o50’, J2000.0) merupakan salah satu pasangan bintang ganda yang paling sering dipelajari. Tulisan ini meragakan hasil perhitungan kembali parameter orbit dan parameter fisik sistim dengan menggunakan cara Thiele-van den Bos, berdasarkan data observasi dari tahun 1900 sampai tahun 2002

Kata kunci: Bintang ganda visual- Hitung orbit

(*) accepted in “Journal Matematika dan Sains, 2007

(view article)