👉 The term "prisometer" is a device used in astronomy to measure the distance between two stars. It works by using an instrument that can be adjusted or moved relative to the stars, allowing astronomers to accurately estimate their distances from each other and each star's position around it. The prism of the instrument consists of mirrors that are rotated to reflect light back onto itself, which then forms a parabolic mirror-like surface that can be used as a measuring tool.