Without the technology of liquid hydrogen and liquid helium, some large scientific facilities would be a pile of scrap metal… How important are liquid hydrogen and liquid helium?

How did Chinese scientists conquer hydrogen and helium that are impossible to liquefy? Even rank among the best in the world? Let us reveal the hot topics such as “Ice Arrow” and helium leakage, and walk into the magnificent chapter of my country’s cryogenic industry together.

Ice Rocket: The Miracle of Liquid Hydrogen and Liquid Oxygen

We China’s Long March 5 carrier rocket, the “Hercules” of the aerospace industry, “90% of the fuel is liquid hydrogen at minus 253 degrees Celsius and liquid oxygen at minus 183 degrees Celsius” – this is close to the limit of low temperature, and it is also the origin of the name “Ice Rocket”.

Why choose liquid hydrogen?

The reason is simple: the same mass of hydrogen has a volume of about 800 times that of liquid hydrogen. Using liquid fuel, the rocket’s “fuel tank” saves more space, and the shell can be thinner, so as to carry more loads to the sky. The combination of liquid hydrogen and liquid oxygen is not only environmentally friendly, but also can produce a greater speed increment and improve engine efficiency. It is the best choice for rocket propellant.

Helium leak: The invisible killer in the aerospace field

SpaceX was originally scheduled to carry out the “North Star Dawn” mission at the end of August, but the launch was postponed due to the detection of helium leak before launch. Helium plays the role of “giving you a hand” on the rocket. It outputs liquid oxygen into the engine like a syringe.

However, helium has a small molecular weight and is very easy to leak, which is extremely dangerous for space technology. This incident once again highlights the importance of helium in the aerospace field and the complexity of its application.

Hydrogen and helium: the most abundant elements in the universe

Hydrogen and helium are not only “neighbors” in the periodic table, but also the most abundant elements in the universe. Hydrogen fusion releases heat to become helium, a phenomenon that happens every day on the sun.

The liquefaction of hydrogen and helium uses the same refrigeration method, and their liquefaction temperatures are extremely low, at -253℃ and -269℃ respectively. When the temperature of liquid helium drops to -271℃, a superfluid transition will also occur, which is a macroscopic quantum effect.

The development of cutting-edge technologies such as quantum computing will have an increasing demand for extremely low temperature environments, and Chinese scientists will continue to forge ahead on the low-temperature journey and contribute more to scientific and technological progress. Salute to the scientists, and let us look forward to their brilliant achievements in the future!