Photogrammetric analysis of horizon panoramas: The Pathfinder landing sitein Viking orbiter images

Tiepoint measurements, block adjustment techniques, and sunrise/sunset pict ures were used to obtain precise pointing data with respect to north for a set of 33 IMP horizon images. Azimuth angles for five prominent topographic features seen at the horizon were measured and correlated with locations o f these features in Viking orbiter images. Based on this analysis, the Path finder line/sample coordinates in two raw Viking images were determined wit h approximate errors of 1 pixel, or 40 m. Identification of the Pathfinder location in orbit imagery yields geological context for surface studies of the landing site. Furthermore, the precise determination of coordinates in images together with the known planet-fixed coordinates of the lander make the Pathfinder landing site the most important anchor point in current cont rol point networks of Mars.