A young visitor operates a programmable robot during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)

A young visitor operates a programmable robot during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)

A contestant takes part in an unmanned aerial vehicle (UAV) obstable course race during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)

Contestants take part in electronics skills championship during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)

Students attend an on-site lecture on robotics during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)

Contestants take part in electronics skills championship during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)

Contestants take part in electronics skills championship during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)

A young visitor poses for photos in a space suit during a juvenile science festival in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Sept. 21, 2019. (Xinhua/Feng Kaihua)