The teacher is so cool! Looking back at the famous scenes of teaching in space

September 10, 2023 is the 39th Teachers' Day in my country. There is a special group of teachers in the distant space. Through space-to-earth communication, they popularize space science knowledge for young people on Earth and give them wings to explore the universe. They are called "space teachers."

From "Hello everyone, I am Wang Yaping, I will be the main speaker of this lecture..." on June 20, 2013, to the long-term operation of the Chinese space station in orbit and the holding of a series of space classroom activities, my country has carried out four large-scale space teaching activities in the past 10 years, demonstrating water film tension experiments, space buoyancy disappearance experiments, liquid bridge experiments, water-oil separation experiments, microgravity environment capillary effect experiments, etc. for young students, introducing astronauts' space life scenes, cell research, and space station rice and Arabidopsis planting research. Behind the smooth progress of space teaching, there are many technical supports.

To conduct space teaching, the first thing that needs to be mastered is the long-distance, long-term, high-quality space-ground communication technology. The Chinese space station flies around the earth at a near-earth circular orbit 400 kilometers above the ground at a speed close to the first cosmic speed. The space teaching lasts about 1 hour. During this time, the space station has flown more than half a circle around the earth, which is "a long way" from the ground. my country uses the Tianlian relay system to ensure stable and good transmission of voice and video signals throughout the space teaching. Since 2008, my country has gradually improved the relay satellite system. In 12 years, it has launched 6 Tianlian satellites to create a relay satellite system with global coverage capabilities.

During the space lecture, multiple high-definition cameras in the Chinese space station transmit high-definition video to the ground in real time through high-speed relay links, and the audio and video of the interactive venues on the ground are transmitted from the ground uplink to the display in the space station via the relay satellite, thus realizing two-way video transmission between the ground and the earth. In addition, the improvement of the performance of basic components of communication technology, the development of carrier technology, and the increase of communication bandwidth will further improve the quality of space-ground communication, and will also promote the development of the space-ground large-capacity information processing industry from the application perspective. The era of big data will also bring new opportunities for the development of the space-ground large-capacity information processing industry.

To successfully complete the space teaching, the astronauts need to "take ten years of hard work to complete one minute on stage". They need to carefully prepare the teaching content, experimental operation, and key points of the explanation, and cooperate with the ground staff to conduct multiple full-process drills. At the same time, the space teaching is aimed at tens of millions of primary and secondary school students across the country. During the ground training, the astronauts also need to take time out to learn from educators to avoid mistakes in the teaching content.

Space teaching is a project with high capital investment and long payback period. The project sows the seeds of space exploration for young people. In the near future, some students who listen to astronauts' space teaching will also devote themselves to the country's space industry.

Chinese astronauts have served as "space teachers" many times, bringing rich, interesting, intuitive and scientific space lessons to the people of the country, forming a unique space science education brand "Tiangong Classroom", while also showing the world the rapid development of my country's manned space technology and injecting new vitality into the development of my country's future space industry. (Author: Cai Yang, Image source: CCTV, Screening Expert: Jiang Fan, Deputy Director of the Science and Technology Committee of China Aerospace Science and Technology Corporation)