In ancient times, stargazing mainly depended on the naked eye. At that time, there were not so many high-rise buildings and heavy industries, and the positions of stars could be directly observed and recorded. Tycho, a famous physicist, recorded a lot of data in the process of stargazing, and Kepler summarized Kepler's three laws according to these data.

In modern society, if you want to observe the stars better, you can go to some empty places or mountains. The stars you see in the mountains are big, bright and dense, and every star seems within reach.

Of course, in addition to observing and recording stars with naked eyes, the ancients also invented many instruments that can record time and position. The standard watch and sundial in ancient China are instruments used to record time. The standard watch consists of two parts, Guiyu and Biao, which are placed vertically with a small hole above the watch. The change of hole shadow position can reflect the change of time.

The armillary sphere is an instrument used to record the position, and Tycho also made his own astronomical instrument in the process of observing celestial bodies.