Complete List of Lesson 2 of Tiangong Classroom in Space Station 2022

In this "Tiangong Classroom", astronauts introduce and show the working and living scenes of China Space Station in orbit. The following is a complete list of the second lesson of the space station 2022 Tiangong class. Welcome to collect and share!

The complete content of the second lesson of the Space Station 2022 Tiangong Classroom

Experiment 1: Warm "ice hockey"

Looking back at the phenomenon, this scene seems to have happened in the "magic world": a transparent liquid ball floated in mid-air, and Wang Yaping clicked it with a small stick, and the ball instantly began to "freeze" and turned into a snow-white "ice hockey" in a few seconds. Wang Yaping said that this "ice hockey" feels warm.

Experts explained that "the space' ice and snow' experiment is actually a process of nucleation and crystallization of supersaturated sodium acetate solution, which will release heat." Zhang Lu, a researcher at the Center for Space Application Engineering and Technology, Chinese Academy of Sciences, said that the crystallization of supersaturated solution usually needs external "disturbance", and the "mystery" of this experiment is that the rod is stained with crystal powder, which provides condensation nuclei for supersaturated sodium acetate solution, and then precipitates sodium acetate trihydrate crystals.

When the crystallization experiment is carried out on the ground, the appearance of the crystal may vary greatly due to the shape of the container. In the microgravity environment, crystals are not restricted by containers, and can be suspended in the air to "grow freely", which echoes the containerless material experimental cabinet in China Space Station. At present, the experimental cabinet of containerless materials has two main purposes: one is to realize the process from melting to cooling and solidification of containerless materials, which is convenient for researchers to collect physical parameters for research; Second, it is used for the on-orbit growth of special materials, shortening the time for new materials to move from the laboratory to the assembly line and enter the public eye.

Experiment 2: "Continuous Pulling" Liquid Bridge

Phenomenon review Ye Guangfu squeezed water on two liquid bridge plates, and the water was spherical, like an upside-down bowl. When the liquid bridge is closed, the two water polo bowls are next to each other. The liquid bridge plates are separated, and a "bridge" with thin middle and thick two ends connects the two plates; Wang Yaping pulled open the liquid bridge plate again, and the liquid bridge became thinner and longer, but it was still unbroken.

Experts interpret Zhang Lu's introduction, and microgravity environment and liquid surface tension are the main reasons for the formation of liquid bridge. The liquid bridge in daily life is not easy to be detected. For example, when washing hands, two fingertips occasionally form a liquid column of several millimeters, and then pull it far away, which will collapse under the action of gravity. On the space station, astronauts can easily demonstrate a liquid bridge hundreds of times larger than the ground, which is impossible to see on the ground.

The surface tension of extended reading liquid is a high-frequency word in "Tiangong Classroom". The water film and water polo experiments conducted in the Tiangong-1 space lecture and the first space lecture of China Space Station all illustrate this principle. Kang Qi, a researcher at the Institute of Mechanics of the Chinese Academy of Sciences, said that the space station can get rid of the influence of ground gravity to the maximum extent, creating good conditions for fluid mechanics research, including liquid bridge experiments. 20 16, 16, Tiangong-2 Space Laboratory was launched with liquid bridge thermal capillary convection experimental project.

Experiment 3: "inseparable" water and oil

Phenomenon Review Wang Yaping vigorously shakes a bottle filled with water and oil, so that the water and oil are fully mixed and the bottle turns yellow. Over time, nothing has changed in the bottle, and the oil droplets are still evenly distributed in the water. Ye Guangfu came to help, grabbed the string tied to the bottle and shook it. After several laps, the water and oil are obviously separated, with the upper layer being oil and the lower layer being water.

Experts interpret "we all know that oil on the ground is lighter than water, and it is common to see oil flowers when drinking soup." Liang Wenjie, a researcher at the Institute of Physics of the Chinese Academy of Sciences, said that in the space station, however, the situation is completely different. The reason why water and oil are inseparable and remain mixed for a long time is because density stratification disappears under microgravity, that is, buoyancy disappears.

"The reason for the successful separation of water and oil in the air is that the bottle is similar to a centrifuge when rotating at high speed, which can be understood as centrifugation to reproduce buoyancy." Zhang Lu said.

Further reading researchers can use the characteristics of microgravity environment to carry out research. For example, in microgravity environment, foam metal, an important material in aerospace, energy and environmental protection, can be obtained by using density stratification to disappear and injecting gas into molten alloy.

In this connection, the high microgravity scientific experimental module can provide a high microgravity environment, and its internal microgravity level is 100 to 1000 times that of the space station module, which is closer to the real space; The external design of air bearing and magnetic levitation reduces the influence of interference factors such as acceleration caused by attitude and orbit control maneuver of space station, torque and vibration caused by various instruments operation, centroid change and impact caused by astronaut activities, solar wind and disturbance of thin atmosphere, which can support more accurate scientific experiments.

Experiment 4: the "ice pier" of somersault

Phenomenon Review The mascot of the Beijing Winter Olympics "Ice Shield" came out at the finale, welcoming the "bright moment" of the space trip. Wang Yaping threw the "ice pier" ornaments horizontally forward, and the awkward gesture of "pier" was extraordinarily light. After several somersaults, he drew a beautiful straight line and stood firmly in Ye Guangfu's hand.

Experts' explanation of parabolic experiments in space shows the phenomenon described by Newton's first law. In the space station, the "ice pier" ornaments are almost unaffected by external forces after being thrown, and maintain an approximately uniform linear motion. Zhang Jian, the main classroom on the ground of the "Tiangong Classroom" and a physics teacher of the Second High School Attached to Beijing Normal University, said that the ideal state of object movement in the eyes of the earth people can now be found in space.

Extended reading: Why should we carry out on-orbit scientific experiments? Zhang Lu introduced that the current experimental projects include: first, revealing special phenomena in microgravity environment, which belongs to understanding the world from a scientific perspective; The second is to help ground scientific research and improve the technical level through on-orbit experiments; Thirdly, there are high vacuum environment, irradiation and sub-magnetic field outside the cabin, and the effects of these special environmental factors on biology, materials and components are also to be studied. The fourth is to further explore unknown areas, including dark matter detection and planetary origin exploration. After the launch of the "Truth and Dream" experimental module, China Space Station will carry out a large number of cutting-edge scientific experiments one after another.

The complete content of the first lesson of the space station 2022 Tiangong classroom

Display of astronauts' working and living scenes in orbit

-Zhai Zhigang introduces the secret weapon "penguin suit"

The astronauts Zhai Zhigang, Wang Yaping and Ye Guang Fu of Shenzhou XIII flight crew vividly introduced and displayed the working and living scenes of the space station.

Being in space, the weightless environment will cause the blood distribution of astronauts to be different from that on the ground, and the blood of lower limbs will swell, so the astronauts' faces will appear "fat". So, how will astronauts fight weightlessness through exercise?

Astronaut Zhai Zhigang said that weightlessness affects our cardiovascular system, bones and muscles. In order to prevent our muscles from shrinking due to weightlessness, there is a secret weapon besides treadmills, bicycles and stretchers in our space station. Do the students see any difference in this dress that Teacher Ye is wearing? From the outside, there is no difference. Let's look at its internal structure.

These are two adjusting rings of the chest drawstring, which are used to adjust the tightness of the chest elastic drawstring. These straps bind the human body tightly, so that the muscles can maintain a certain tension for a long time, which can effectively prevent muscle atrophy caused by weightlessness. The name of this suit is penguin suit.

During the lecture, netizens found Wang Yaping in the sleeping area of the space station, with her family photo on it. She also said that she can "talk to her family at night" on the space station. Let netizens feel that family members are always dependent!

Item 2

Space cytology research exhibition

-Ye Guangfu shows you the beating heart muscle cells in weightlessness.

Ye Guangfu, astronaut of Shenzhou XIII crew: At present, we are conducting research on cell growth and development under weightlessness. In the early stage, we have done a lot of research on cells. At different times, at different times and in different units, we have cultivated cells through an artificial mechanism in a state of complete weightlessness. Then compare the two groups of cells to see what changes their growth and morphology are under the condition of motivation and unpowered. Then we will further study its changing law and mechanism. And we also choose different types of cells to study, including skin stem cells and myocardial cells.

Ye Guangfu, astronaut of Shenzhou 13 crew: This is a picture of myocardial cells observed under a fluorescence microscope. Did the students see the flashing fluorescence? Do you know why? In fact, this is a reaction of the cell's own bioelectricity, because these cells are alive. It is amazing that we can see such a picture by using the special means of bioelectricity to stimulate fluorescence.

Ye Guangfu, astronaut of Shenzhou XIII crew: These are also myocardial cells. They shrink in the form of patches. You can take a closer look. They move like heart muscle, and their movements are very rhythmic. They are jumping happily inside, as if to tell everyone that we are alive and well. Isn't it amazing? Welcome to participate in cell research in space!

Item 3

Spatial steering

-Ye Guangfu tried to complete the space turn without the help of the handle.

A classmate in Beijing asked him if he could walk normally in space like on the ground. Ye Guang answered his question with action: No! It turns out that in space, without the help of gravity, people can't walk like on the ground, but just float around.

If you can't walk in space, what about walking around in space? The answer is not that easy! After trying many methods, Ye Guangfu finally turned around and succeeded.

"Hey, I'm floating." I took a deep breath. First, the secret weapon of space "penguin suit" was displayed, and then "spacewalk" was non-stop. Finally, he was asked to try to complete the space turn without the help of the handle. Ye Guangfu was called Teacher Ye, a tool man in the Temple of Heaven by netizens. Wang Yaping said: "Although Mr. Ye has worked hard, it seems that he has not succeeded yet ... Come on, work harder!"

Item 4

Buoyancy disappearance experiment

-Wang Yaping reveals why table tennis can stay in water in space.

In the first lesson of Tiangong Classroom, Wang Yaping also made an experiment of buoyancy disappearing. In space, table tennis doesn't float on the water like it does on the ground, but stays in the water. Why?

Astronaut Wang Yaping said that this phenomenon is completely different from that on the ground, because buoyancy is generated with gravity and almost disappears in the weightless environment in space, so table tennis can't float like it does on the ground.

Item 5

Water film tension experiment

-The flowers made by Wang Yaping and his daughter bloom in space.

In the "Tiangong Classroom", astronaut Wang Yaping, with the help of Zhai Zhigang and Ye Guangfu, took out an origami flower completed with his daughter and demonstrated the water film experiment. Subsequently, the flower "bloomed" in space.

Item 6

Water polo optical experiment

-Wang Yaping demonstrates how the water polo presents a positive image and a negative image in microgravity.

How to form water polo in weightless environment? Why are there positive and negative images? Wang Yaping will take you to do an interesting experiment.

Wang Yaping, astronaut of Shenzhou XIII: Now we pour water into the water film to make a big water balloon. As we all know, this is because the surface tension of water in weightlessness will show great power, so we can make water polo that cannot be made on the ground.

Wang Yaping, astronaut of Shenzhou XIII: Let's add some water to make the water polo bigger, rounder and more beautiful.

Wang Yaping, astronaut of Shenzhou XIII: Students, can you see an enlarged me now? I did this in the last space lecture, and we all know that this is the result of convex lens imaging.

Wang Yaping, astronaut of Shenzhou XIII: First, please ask Mr. Ye to extract the bubbles from the water polo, and then we will inject a big bubble into the water polo. Students, now you see two images, one is right and the other is wrong? It's hard to see on the ground.

Wang Yaping, astronaut of Shenzhou XIII: Students can also consider it. Why are there two images, one positive and one negative? Interested students can study it in depth. I can give you a hint here. This is because bubbles divide the water polo into two parts, which are imaged separately.

Item 7

Effervescent tablet experiment

-What happens when effervescent tablets are put into space water polo? Wang Yaping: Sweet and happy bubble ball.

As we all know, effervescent tablets produce a lot of bubbles when they meet water, so what happens when effervescent tablets meet water polo in space?

Today (9th), in the first class of Tiangong classroom, Wang Yaping, a space teacher, made such an experiment. I saw effervescent tablets bubbling constantly in the water polo, but in weightless environment, although bubbles were constantly generated, they did not leave the water polo. With more and more bubbles, the water polo has gradually become a "bubble ball" full of joy, and it produces bursts of fragrance.

The Significance of Tiangong Classroom

This is a vivid patriotic education class. The meaning of "Tiangong Classroom" is not only popular science. The podium is located in the boundless space, and the classroom is in the land of China. Far apart, teachers and students interact freely, as if in the same classroom. Behind this seemingly simple interaction is a true demonstration of China's space technology strength. Not only that, in this unique class, astronaut Wang Yaping showed everyone around the space station. Whether it's reclaimed water or a "penguin suit" that can reduce the impact of weightlessness on the body, all items full of scientific and technological content make people marvel at China's scientific and technological strength. This is also refreshing and eye-opening for the young people of all ethnic groups in Xinjiang, and will certainly enhance their ambition, backbone and confidence in being China people. From this perspective, Tiangong Classroom is a rare patriotic education.

Science is the cornerstone for a country to go far away. "Tiangong Classroom" ignites the dream of science and even the dream of strengthening the country. More teenagers are looking up at the starry sky, let the seeds of dreams sprout in their hearts and let the scientific spirit carry forward. They will surely become a solid force for building a world power in science and technology.

The complete content list of related articles in the second lesson of the space station 2022 Tiangong class:

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★ Introduction to the second lesson of 2022 Tiangong Classroom

★ 7 articles in the second lesson of Tiangong Classroom 2022.

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