Contestants check a new energy vehicle taking part in a competition, which is part of a series of events to be held on the National Popular Science Day at Olympic Park in Beijing, Sept 14, 2017.[Photo/China Daily]

Contestants check a new energy vehicle taking part in a competition, which is part of a series of events to be held on the National Popular Science Day at Olympic Park in Beijing, Sept 14, 2017.[Photo/China Daily]

A woman experiences a VR game at the Beijing Science Carnival which kicked off at Olympic Park in Beijing, Sept 14, 2017. [Photo/China Daily]

Models of the Long March rocket family exhibited at the Beijing Science Carnival which kicked off at Olympic Park in Beijing, Sept 14, 2017. [Photo/China Daily]

Students enjoy themselves at the Beijing Science Carnival which kicked off at Olympic Park in Beijing, Sept 14, 2017. [Photo/China Daily]