The Locus of the Horizon of the Planisphere, Divided into the Northern Sky and the Southern Sky

—Simple Drawing with Spreadsheet Software—

Abstract

A planisphere plate is a projection of the spherical sky into a flat sheet. The type of planisphere with one whole-sky plate has a problem in terms of scale: essentially, when observed from low latitudes, southerly constellations are greatly distorted. One way to solve this problem is to split the northern sky and the southern sky on the planisphere. Therefore, in this study, I aimed to demonstrate that the celestial sky, divided into Northern and Southern hemispheres along the trajectory of the horizon of planisphere, could be represented by simply via the use of spreadsheet software. I also examine the possibility of drawing the celestial prime vertically rather than horizontally, as typically drawn in a planisphere. Some ideas for lesson practice can be drawn from this study, for teaching at the Elementary and Secondary levels. The intention is not to make this material easily understandable to all students from the beginning, but rather to foster students’ critical thinking and discovery by eliciting their understanding of how to find the horizon of a planisphere. It is hoped that making and using planisphere in science lessons will be a useful learning tool in Elementary and Secondary school settings and in science education facilities.