MOON PHASES AS GIS COMPUTER APPLICATION

Document Type : Original Article

Authors

Zaqaziq University.

Abstract

In this paper, Moon phases will be investigated as a computer application in GIS. Moon phases depend on the position of moon and sun relative to the earth observation points. Objective of this study will be based on the following: (1) The concept of GIS and SDB, where the data measured to determine the moon phases have features as spatial data and can be treated as GIS. (2)The spatial data will be measured at any point on the surface of earth (local view), but all the data models as well as queries will be handled relative to the center of earth. The center of earth can be considered as the global point of view for all the spatial data of the moon phases. Therefore, a special transformation (direction cosine matrix) will be used to transform from local view to global view and vise versa. (3) The moon and sun position modeling which have a lot of work done during the history. The most recent model data will be used in this work. As a result of this work, we can overcome the difficulties due to the local view. Crescent as one of the most critical moon phases is seen in some parts of the earth, and not others. Therefore in this paper we will try to determine the locus of points on earth surface which has the scene of the moon phases of the global view at earth center, i.e. the locus of points at the local view which has the same scene of moon phases as global view.

Keywords