Few observation binary orbit solver (<scp>fobos</scp>) from two (or more) astrometric observations

ABSTRACT We have developed a new, fast method of estimating the orbital properties binary or triple system using as few two epochs astrometric data. fobos (Few Observation Binary Orbit Solver) uses flat prior brute force Monte Carlo to produce probability density functions likely parameters. test code on fake observations and show that it can (fairly often) constrain semi-major axis within factor 2–3, inclination ∼20° from only observations. also 68 95 per cent confidence intervals are statistically reliable. Applying this systems allows relative secondary tertiary star orbits be constrained. usually find significant number possible matches in CPU minutes for systems, hours systems.