The Long March 4B rocket took off from China’s Taiyuan Satellite Launch Center on Monday with a remote sensing satellite. The 50-year-old spacecraft is located in northwestern China, about 500 kilometers southwest of Beijing.
As often begins with the first stage of the Chinese rocket from the inner Taiyuan facility, the spent Long March 4B booster fell below the spaceport. In this situation, it approached a school, creating an estimated large cloud of toxic gas.
Unlike many of the world’s space airports, many of China’s launch sites are located inland rather than close to the water to avoid such threats. For security purposes, amid tensions between China and the United States and the Soviet Union, it built three large opening centers off the water during the Cold War.
Some impressive footage of the return of the first phase of today’s Long March 4B.
– LaunchStuff (@ LaunchStuff) September 7, 2020
In recent years, China has begun experimenting with grid fins to get its rockets back to Earth – and finally for land boosters like the SpaceX, as it does with the Falcon 9 rocket. However, the project seems to be more influenced by the desire to master recycling technology than to save its population, as China has been less visible to people around Taiwan since 1968.
Complicating the problem of the first phase of rocket launches in the surrounding countryside is that China has been using toxic hydrogen fuel for its first phase. Hydrogen, which is two nitrogens bound to hydrogen atoms, is an efficient, steel fuel. But it is also extremely harmful and toxic.
When a do dragon The spacecraft exploded During an experiment in April 2019, it produced large clouds of toxic orange gas that could be seen for miles around the coast of Florida. These red clouds were caused by nitrogen tetroxide, an oxidizer that burns with hydrogen fuel. The spacecraft – and in the past many included the space shuttle – used sustainable propellants to operate in space. NASA Is working To find “green” propellants that prevent the need to use hydrazine for internal operations as well.
However, this is a different story for Rocket. Hydrogen has been phased out to be used as vehicle openings. The last major US rocket to use hydrazine was the United Launch Alliance’s Delta II rocket, which used toxic fuel in its second phase. The rocket retired in 2018. Russia’s work horse proton rocket uses hydrogen for its first and second phase.
However, the majority of Chinese fleets have hydrogen fuel and nitrogen tetroxide oxidizers. This includes the human-rated Long March 2F rocket as well as the widely used Long March 4 family. All of these rockets, with their toxic first phase, launch to the ground and many events have occurred over the years. These fuels are cheap and relatively easy, and it would have been natural for China to use these boosters when they were developed in the 1980s and 1990s. But their use continues today.
China is slowly changing. The new family of its larger rockets, the Long March 5 fleet, is powered by liquid oxygen and kerosene like SpaceX’s Falcon 9 rocket. Ironically, the Long March 5 rockets typically cross the Wenchang spacecraft launch site launch ocean.