## Introduction

The fundamental goal of multistation meteor observations is to accurately estimate the meteor’s trajectory through the Earth’s atmosphere and ultimately derive its Keplerian orbital elements in the solar system. With that information, one can then associate a particular meteoroid with a parent body such as a comet or asteroid, provide insight into the dynamical evolution of meteoroid streams, deduce the characteristics of the parent bodies, and perform both validation and refinement of shower streams in the IAU data base. The basic computation involves the combination of multiple views of the meteor’s luminous track to determine its atmospheric path. Existing methods to solve for meteor trajectories have been well documented in several papers and include the intersecting planes method (Davidson 1936; Porter 1942; Whipple and Jacchia 1957; Wray 1967; Ceplecha 1987; Bettonvil 2005), as well as a straight least squares approach (Borovička 1990). In addition, the image processing literature addresses this problem under the more generic title of “Trajectory Triangulation,” some papers of which are applicable to meteor flight when employing multiple cameras (Kaminski and Teicher 2002, 2004).

The conventional trajectory estimation methods that have been typically used in the meteor community solve for a meteor’s path through the atmosphere using a two-step boot-strapping technique. First the orientation and position of the track is obtained, followed by a solution for the velocity and deceleration along the track. The new approach, as described in this paper, can best be described as a “multiparameter fit” algorithm, and attempts to estimate all unknown parameters simultaneously. The algorithm iteratively solves a fully coupled motion propagation model, converging to the most likely 4-D trajectory in 3-D space plus time that best matches the measurements. The algorithm is designed to handle multiple cameras from two or more disparate sites as well as additional camera tracks obtained from the same site. The method provides greater robustness and accuracy and permits the processing of station geometries with smaller inherent convergence angles to the meteor. The algorithm has been applied routinely on video meteor data from the Cameras for All-sky Meteor Surveillance (CAMS) as described briefly at the 2010 International Meteor Conference (Gural 2011) and then again in another paper with significantly more details that covered the collection, archiving, detection, coincidence, trajectory, and orbital estimation for multistation meteors (Jenniskens et al. 2011).