China's methane-powered rocket Zhuque-2 Y2 has been successfully launched from northwestern China. This is the first rocket in the world with such a propellant to be launched into orbit. One of the designers of the rocket explains to CGTN why the model is so important to the future of space travel. 

ZHENG YIBING, CGTN Reporter "Thank you very much for receiving our interview. So, after the success of the mission, what's your feeling now?"

DAI ZHENG, Deputy Chief Designer of Zhuque-2 "We officially began research and development for Zhuque-2 in the second half of 2017, and it's been nearly six years. So our entire team has been waiting for this success for a very long time. After the failure of the launch in December last year, we underwent a thorough check from the very start. Like I said, space is challenging, and any small problems can bring about the collapse of the entire system. It's either a yes or no and there's no middle ground. So for us, the failure last year was also very painful. We've been working hard for a long time to achieve success."

ZHENG YIBING, CGTN Reporter "Why Zhuque 2 uses methalox (the combination of methane and liquid oxygen) as propellant and what are its advantages?"

DAI ZHENG, Deputy Chief Designer of Zhuque-2 "Because liquid oxygen methane is actually highly suitable for commercial launch vehicles, especially for the development of reusable rockets. It's much cheaper than liquid hydrogen, liquid oxygen, and the liquid oxygen kerosene that we are familiar with, because we have a very large LNG energy industry that's supporting the supply of methane. The second point is that methane is not relatively easy to accumulate carbon, when the engine is burning, and it's not easy to accumulate carbon on the turbine disc. The commercial space companies, including those in the United States, have chosen liquid oxygen methane as propellant for its potential in reusable scenarios."

ZHENG YIBING, CGTN Reporter "So, what kinds of technical improvement measures you would do for this rocket? And how do you plan for the reusable launch vehicle?"

DAI ZHENG, Deputy Chief Designer of Zhuque-2 "First, we're going to use super cool refueling, which means lowering the temperature of the propellant, and to improve the performance of the rocket. Second, we'll make the engine nozzle bigger, so as to add activation during the second stage to improve the carrying capacity of the rocket. Then the third step is that our rocket engine will continue to carry out thrust enhancement. Our reusable rockets' development has started. It's still based on our "Tianque 12" 80-ton liquid oxygen methane engine. So, we expect to complete the first test flight in the second half of 2025."