To use the new sphere pixelization method SREAG

Abstract

A new method SREAG (Spherical Rectangular Equal-Area Grid) was proposed in Malkin (2019) to divide a spherical surface into rectangular cells of equal area. SREAG grid consists of a set of rings parallel to the equator, and each ring is divided into several cells, the number of which depends on the mean latitude of the ring. This paper presents some SREAG features in more details. The minimum number of rings is four. The maximum number of SREAG rings that can be achieved when using a 32-bit integer is 41068, which corresponds to the full range of resolution from $\sim$45$^{\circ}$ to $\sim$16$''$ The computational accuracy of SREAG is also estimated. Simple expressions were derived to calculate the basic SREAG parameter, number of rings, for the desired number of cells or for the required grid resolution.