Beijing Planetarium is one of the earliest planetariums in my country. It is divided into two parts: A Hall (old hall) and B Hall (new hall). The hall is mainly composed of wonderful theater performances. Visitors can learn about the origin and development of the universe and learn astronomical knowledge by watching exciting high-tech movies, observing observatories, visiting exhibitions and other activities. The Planetarium is an important area in Hall A. The hall has a spherical dome with a diameter of 23.5 meters. Advanced instruments are used to realistically restore the 9,000 or so stars visible to the naked eye on the earth, bringing the audience a real starry sky experience. Hall B has three astronomical theaters, including the cosmic theater, 3D theater, and 4D theater, as well as various popular science education facilities such as astronomical exhibition halls, solar observatories, public observatories, and astronomical classrooms. Among them, the cosmic theater with a radius of 18 meters has a standard hemispherical full-sky screen, which can present a magnificent three-dimensional sky effect to 200 spectators at the same time, which is unique in mainland my country. The 4D theater can not only present lifelike three-dimensional images, but also create a variety of effects such as water spray, wind spray, and leg slapping, bringing you an immersive and wonderful science experience. The 3D theater presents scientific knowledge to the audience with realistic and gorgeous three-dimensional effects, truly achieving the goal of combining education with entertainment.