Universe-level production! Astronauts shoot "space station blockbuster" in orbit, how is it shot?

Produced by: Science Popularization China

Author: Shi Chang (PhD in Physical Chemistry)

Producer: China Science Expo

World Photography Day is a major festival for photography enthusiasts around the world. Every August 19, we enjoy the beautiful photos taken by photographers. On World Photography Day in 2024, we are fortunate to enjoy the "space station blockbusters" from space photographers.

Sunshine

(Photo credit: China Manned Spaceflight WeChat Official Account/astronaut Ye Guangfu)

Blue star outside the window

(Photo credit: China Manned Spaceflight WeChat Official Account/astronaut Ye Guangfu)

Magnificent mountains and rivers

(Photo credit: China Manned Spaceflight WeChat Official Account/astronaut Ye Guangfu)

The space photographer is Ye Guangfu, the commander of the Shenzhou 18 manned spacecraft. He captured the dazzling beauty of the earth through the porthole of the space station, and a series of "space station blockbusters" beyond imagination are shocking. What conditions are needed to take these photos?

Space station portholes: astronauts' "windows" to view the outside world

To take photos in the space station, you first need a great viewing window, which is a porthole. A porthole is a watertight or airtight circular or specially shaped window that provides ventilation, lighting, and scenery viewing.

In the space station, the porthole is not only a window for astronauts to enjoy the beauty of the earth, but also a key facility for observing the operation status of the spacecraft, conducting scientific experiments and ensuring the safety of astronauts. It is this window similar to the windshield of a car that provides the prerequisite for astronauts to "take pictures".

Space station porthole

(Photo source: veer photo gallery)

The glass is getting brighter and the pictures are getting clearer.

As a window for observing the outside world, portholes must first have high clarity. If we compare the photos taken by Chinese astronauts in space, it is not difficult to find that the clarity of the photos taken by astronauts from Shenzhou V to Tiangong Space Station is getting higher and higher. This is inseparable from the transparent portholes.

Friends who drive have had this experience: after driving for a long time, many stains will appear on the windshield, which greatly affects the clarity of our observation of the outside world. The same is true for portholes, especially under the impact and friction of high-energy particles in outer space, the surface is easily scratched.

Car windshield stains

(Photo source: veer photo gallery)

To address this problem, the Shanghai Institute of Ceramics, Chinese Academy of Sciences, has developed a high-tech anti-pollution coating that acts like an invisible shield, protecting the portholes from cosmic dust and particles, ensuring that the spacecraft's "eyes" are always clear and bright. This technology provides astronauts with an excellent viewing experience, allowing them to enjoy the beautiful scenery of their home planet without any hindrance.

Sturdy and reliable, high-tech space station windows

The space station orbits the Earth in an elliptical orbit in the near-Earth region, periodically entering the Earth's shadow and sunlit areas. This rapid position change causes huge temperature fluctuations in the space station, with the maximum temperature difference exceeding 200°C.

If a glass containing hot water is immediately filled with cold water, there is a risk of bursting, and the same is true for the porthole glass of the space station. Ordinary glass can hardly withstand such a large temperature difference. What material can bear this heavy responsibility?

Cracked cup

(Photo source: veer photo gallery)

Fused silica glass , also known as fused quartz glass, is a special, high-tech material. The glass experiences a temperature of thousands of degrees during its preparation and has an extremely low coefficient of thermal expansion, which enables it to maintain structural stability in extreme high and low temperature environments. In addition, this type of glass also has extremely high strength and can withstand the impact of high-speed flying space debris. Its strength is much higher than that of bulletproof glass.

The cost of this high-tech material space station porthole is definitely not cheap, but there are more than one such porthole in China's Tiangong space station. According to reports, there are such portholes in the core cabin sleeping area and the Wentian cabin sleeping area of ​​the Tiangong space station. And as the construction of the space station continues to improve, the "sky view room" of Chinese astronauts will add more viewing windows to meet more comprehensive observation needs.

space station

(Photo source: veer photo gallery)

Stable flight posture, special "anti-shake" technology

Maintaining the flight attitude of China's Tiangong space station is also a key factor in the astronauts' "filming". The control torque gyro is a key device for the space station's attitude control. It uses a high-speed rotating flywheel to obtain angular momentum and outputs torque to the outside by changing the direction of angular momentum, thereby achieving precise control of the space station's attitude.

Gyroscope

(Photo source: veer photo gallery)

This technology was once a "stumbling block" for China's aerospace technology. In order to break through the problem of core technology being blocked by foreign countries, Chinese aerospace personnel have made unremitting efforts to develop a control torque gyro system that combines the advantages of high precision, fast response, long life and high reliability, providing basic guarantees for the shooting of large porthole films.

Advanced photography technology is a powerful tool for astronauts to take photos

When you meet the above conditions, can you take photos in space? Everything is ready, only the "east wind" is missing, and this "east wind" is advanced photography equipment. In recent years, the development of photography technology has been rapid, and the camera pixels of mobile phones can easily reach tens of millions or even hundreds of millions. Taking photos of the moon has become a must-have skill for major mainstream photography equipment.

The advanced ultra-high-definition camera array can easily capture images with more than 100 million pixels and maintain rich details and saturated colors. Coupled with the camera's built-in adaptive optical system, it can compensate for image blur caused by atmospheric disturbances and slight vibrations of the space station in real time, making it no longer difficult to "take photos" of the space station.

digital camera

(Photo source: veer photo gallery)

With the rapid development of aerospace technology and the continuous advancement of science and technology, our understanding of the earth is becoming more and more in-depth. These high-tech achievements not only allow us to witness the magnificence and magic of the earth, but also inspire human beings' infinite curiosity and desire to explore the unknown world. In the future, we have reason to expect the birth of more shocking "space station blockbusters" and witness the glorious chapter of human aerospace industry together!

References:

1.Dote H , Theodore KT .Structural analysis and test Space Shuttle Orbiter window system[J].Journal of Spacecraft & Rockets, 2013.

2.Margiotta DV, Peters WC, Straka SA, et al. The Lotus coating for space exploration - A dust mitigation tool[J]. Proceedings of SPIE - The International Society for Optical Engineering, 2010.

3. Bai Yu, Pang Hewei, Gong Zizheng. Tracking study on damage of spacecraft window glass caused by tiny debris[J]. Spacecraft Environment Engineering, 2009.

4. Jin Lei, Xu Shijie. Study on spacecraft attitude tracking control using single-frame control moment gyro and momentum wheel[J]. Acta Astronautics, 2008.

5. Yuan Jianpeng. Application of coating technology in aerospace materials[J]. New Materials Industry, 2012(10):5.DOI:10.3969/j.issn.1008-892X.2012.10.013.