Astronauts aboard China's Tiangong space station played a game of ping-pong using a droplet of water instead of a ball during a space lecture on Wednesday, captivating students with a vivid demonstration of fluid mechanics and material science in microgravity.

The Shenzhou-23 crew, commander Zhu Yangzhu, spacecraft pilot Zhang Zhiyuan, and Lai Ka-ying, the first payload specialist from China's Hong Kong Special Administrative Region (SAR), delivered the Tiangong Class session specially designed for students in the Hong Kong and Macao SARs.