Eclipse Timing as a Method to Determine Distance and Orbital Orientation.

Jason Rowe ( Université de Montréal )

We present a method to determine distance and orbital orientation based on the timing of eclipses. The parallax effect from observations across large baselines combined with the orbital motion of distant gravitationally bound systems produces observed changes in the timing of observed eclipses. When viewing an eclipsing system from different locations the observed occurrence eclipse will vary, both linearly with the distance of the observer and linearly with the angle of orbital orientation relative to the baseline of observations. Combining eclipsing time with an independent estimate of distance the projected orbital orientation can be determined, or alternatively by examining a large sample of timed eclipsing systems a statistical measurement of a preferred orbital plane can be determined. We present a simple framework to include the effects of parallax, orbital motion and eccentricity and discuss the required precision and potential observational strategies and techniques.