Visitors walk into a "black hole" at the newly-unveiled Shanghai Astronomy Museum on July 18, 2021. The museum, the world's largest planetarium in terms of building scale, opened on July 17. [Photo/IC]

People visit the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

Visitors take photos of the "sun" at the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

Children touch the "sun" at the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

A bird's-eye view of the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

A child observes the microstructure of a meteorite at the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

Visitors learn about gravitational wave at the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

Visitors rest under the dome theater at the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

A model of Yutu-2 lunar rover is on display at the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]

Visitors line up in front of the Shanghai Astronomy Museum on July 18, 2021. [Photo/IC]