The "Tiangong Class" Hong Kong and Macao Designated Session was held simultaneously in Hong Kong and Macao on Wednesday morning, as the three Chinese astronauts of the Shenzhou-23 crew currently carrying out a manned space mission at the Tiangong space station delivered a live space lecture for students.

Shenzhou-23 mission commander Zhu Yangzhu, astronaut Zhang Zhiyuan and Hong Kong's first payload specialist Li Jiaying, or Lai Ka-ying in Cantonese, delivered an engaging and vivid science lesson to the young people of Hong Kong and Macao.

The event was jointly organized by the Hong Kong Special Administrative Region (HKSAR) government, the Macao Special Administrative Region (SAR) government and the China Manned Space Agency, with the main classroom set up at Lai's alma mater, Tsuen Wan Public Ho Chuen Yiu Memorial College in Hong Kong.

A total of 160 Hong Kong students and 50 Macao students attended the main venue in person, joined by school principals, teachers, youth representatives, and tech professionals from both cities.

The HKSAR government and the Macao SAR government also arranged for teachers and students of primary and secondary schools to watch the live broadcast simultaneously on campus.

During the session, the three astronauts demonstrated scientific experiments in the unique space environment in real time and shared glimpses of daily life aboard the space station. They conducted a series of science demonstrations, including baking a cake in the space kitchen, wringing out a wet towel, and tending the space vegetable garden.

Lai also showcased the operating procedures for MUSICO, a lightweight, high-resolution, high-precision carbon dioxide and methane point-source detector developed under the leadership of the Hong Kong University of Science and Technology.

Throughout the lecture, the astronauts answered questions from students on space science and astronaut life in orbit.