A worker works at the construction site of the Shanghai Planetarium in Shanghai, east China, June 12, 2018. All of the main steel structure projects of the Shanghai Planetarium have been completed on Tuesday. Covering 38,164 square meters, the planetarium will include a main building and ancillary constructions such as an observation base for young people, a solar tower and observatory. It is expected to open in 2020. (Xinhua/Fang Zhe)