Methods of smoothing applied to differences in star positions in observational catalogues

Abstract

Three different methods, Whittaker - Robinson - Vondrak (WRV), cubic spline (SPL) and Expansion of the Elementary Trigonometric and Exponential Functions (ETE), are applied to differences in star positions of five observational catalogues in order to eliminate random errors. The Belgrade, Kiev, Moscow, Odessa and Kharkov catalogues of double stars (DS) programme have been used. The ETE method appears as reliable and even somewhat more efficacious that the usual WRV and SPL methods.