theory of expounding appearance in the night sky

The period between the 3rd and 6th centuries witnessed enormous develop-ment in China's astronomy, with the rise of many theories on the cosmic structure.The most important of these were the theory of canopy-heavens, the theonrt of sphere heavens, and the theory of expounding appearance in the night sky. The Theory of Canopy-Heavens

公元3到6世纪是中国天文学快速发展的时代。在这段时期内，涌现了许多讨论天地结构的学说，其中最重要的是盖天说、浑天说和宣夜说。

The theory of sphere-heavens played an important part in the history of Chi-nese astronomy, exerting significant influence on the design and manufacture of anaent astronomic instruments, as well as on the explanation of relevant astro-nomic theories. The Theory of Expounding Appearance in the Night Sky

浑天说在中国天文学史上占有重要的地位，对中国古代天文仪器的设计与制造产生了重大的影响，对天文学的有关理论问题的解释也产生了重大影响。

hence giving rise to the new theory of expounding appearance in the night sky.

所以就又产生了一种新的理论“宣夜说”。