Since antiquity, people have observed the night sky. To establish order and predictability, people made maps of the heavens. Two kinds emerged. The first were star maps, organized into constellations but focused on stellar location in the sky. Stars were placed in a coordinate system, initially based on celestial latitude and longitude oriented to the ecliptic, but later based on decl. and R.A. oriented to the celestial equator. Over time, telescopic and scientific needs called for more detailed coordinate systems, and constellation images disappeared. The second kind of heavenly map depicted the solar system and focused on planetary locations and surface characteristics. For many centuries, these were cosmological diagrams with concentric planetary and stellar circles, centered first on the Earth and then the Sun. Now such maps have no stellar boundary, and ever larger telescopes and space probes allow us to view planetary surfaces in unprecedented detail.

自古以来，人们就观察夜空。为了建立秩序和可预测性，人们制作了天空地图。出现了两种。第一个是星图，组织成星座，但专注于天空中的恒星位置。星星被放置在一个坐标系中，最初基于面向黄道的天体纬度和经度，但后来基于decl。和 RA 指向天赤道。随着时间的推移，望远镜和科学需要更详细的坐标系，星座图像消失了。第二种天图描绘了太阳系，侧重于行星位置和表面特征。许多世纪以来，这些都是具有同心行星和恒星圆的宇宙图，首先以地球为中心，然后以太阳为中心。