Asteroid mass determination at Nikolaev Observatory

Masses of asteroids are topical for research in ephemerides computations and density evaluations. Details of the dynamical method are given for asteroid mass determinations. Preliminary masses of 13 asteroids, obtained with relative errors less than 50%, are presented from non-weighted least squares. Accuracy improvement of mass values for dynamical computations is evident using contemporary observations of 1999–2006. Statistics of the fitting ephemerides to the observations is also discussed.