Potential of ASTER and LANDSAT Images for Mapping Features in Western Desert

In Egypt, most of the topographic maps need updating. Also, there are large areas haven't mapped yet. The Western Desert is an example of these poorly mapped areas. Globally, there are many sources of the free satellite images like ASTER and LANDSAT. The study aims to evaluate and improves theses satellite images in order to derive planimetric features for medium scale maps for this important area. Two images of ASTER and LANDSAT were prepared and assessed in order to distinguish their accuracies, the evaluation was based on accurate G.P.S observation data. After registration and geometric correction they were subjected to a process of fusion. The results conclude that: referring to map accuracy standards, the fused image resulted from ASTER and LANDSAT is valid for the intended purpose after registration and geometrically corrected using at least one GCPs for every 15 square kilometers