On [specific date], China successfully launched a low-orbit satellite for satellite internet using the Long March 8A carrier rocket (also known as the modified Long March 8 carrier rocket) from the Wenchang Spacecraft Launch Site. The satellite entered its predetermined orbit smoothly, marking a complete success of the launch mission and signifying the addition of a new member to China's new generation of carrier rocket family.

On [Month] [Day] at [Time], China successfully launched a low-orbit satellite for the satellite internet constellation using the Long March 8 modified carrier rocket at the Wenchang Space Launch Site. The satellite entered its predetermined orbit smoothly, marking the complete success of the launch mission. Photo by Guo Cheng, Xinhua News Agency.

Song Zhengyu, the chief designer of the Long March 8A carrier rocket at the First Academy of the China Aerospace Science and Technology Corporation, explained that the Long March 8A carrier rocket is an improved version developed on the basis of the Long March 8 rocket, tailored to meet the future launch requirements for mega-constellation networks in medium and low Earth orbits. It retains the core first stage and boosters of the Long March 8 rocket, while the core second stage is newly developed with a .-meter diameter universal hydrogen-oxygen upper stage, equipped with a .-meter diameter fairing.

Together with the basic model of the Long March 8 carrier rocket and the tandem configuration without boosters, they form the Long March 8 series of carrier rockets, creating a tiered capability for launching payloads of several tons into sun-synchronous orbit, significantly enhancing China's ability to launch satellite networks in low and medium Earth orbits," said Song Zhengyu.

Song Zhengyu revealed that the Long March 8A carrier rocket innovatively integrated the functions of the satellite bracket, adapter frame, and instrument module into a multifunctional module, successfully reducing weight by kilograms and improving the rocket's carrying efficiency. This integrated design approach applied to the rocket structure is the first of its kind in the country.

Additionally, as the first rocket to feature a .-meter diameter final stage paired with a .-meter diameter fairing, the Long March 8A carrier rocket appears to have a "larger head" in terms of its shape. This design provides satellites with more space, accommodating a wider variety and larger volume of satellites, thereby enhancing mission adaptability.

What are the "outstanding features" of the newly developed 5-meter diameter universal hydrogen-oxygen upper stage? Fan Chenxiao, a designer from the First Academy of China Aerospace Science and Technology Corporation, explained that it can carry more fuel and incorporates new technologies, products, and processes such as a new foam sandwich common bulkhead tank, a closed expander cycle engine, and a new electrically controlled safety relief valve. These enhancements significantly increase the payload capacity, effectively reduce the satellite's time to orbit, save fuel, and extend the satellite's lifespan.

"The final stage of rockets using liquid hydrogen and liquid oxygen as fuel has the characteristic of high specific impulse, enabling the rocket to achieve relatively large thrust with less fuel, which is currently the propellant with a relatively high specific impulse that our country has mastered," said Liu Lidong, a designer at the China Academy of Launch Vehicle Technology. In the planning of the new generation of medium-sized launch vehicle models in our country, the main configurations of future medium and high orbit launch vehicles will adopt the hydrogen-oxygen final stage.

Liu Lidong explained that before the advent of the universal hydrogen-oxygen upper stage, China only had hydrogen-oxygen upper stages with a diameter of meters, which could no longer meet the development needs of China's new generation of medium-sized launch vehicles in terms of rocket body diameter and power system optimization. Choosing the hydrogen-oxygen upper stage module for universal design can meet the unified product specifications for China's new generation of medium-sized rockets, enhance the productization level of the module, improve production efficiency, and further reduce costs.

Song Zhengyu stated that the 5-meter diameter universal hydrogen-oxygen upper stage will serve as a mature module in the future, available for selection by other rockets, significantly enhancing the carrying capacity of the Long March series of launch vehicles.

长征八号甲运载火箭首发成功的背后是中国航天近年来的蓬勃发展。探索浩瀚苍穹，长征系列运载火箭见证一次次启航与奔赴。蛇年首发“开门红”，中国航天定能“巳巳如意”，向着星辰大海扬帆启新程！（记者宋晨、陈凯姿） Statement: Xinhua Finance is the national financial information platform constructed by Xinhua News Agency. Under no circumstances does the information released by this platform constitute investment advice.

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