The first crucial step of the Chang'e-6's historic journey to retrieve samples from the far side of the Moon is made possible by China's most powerful carrier rocket, the Long March-5Y8. Sun Ye finds out how the rocket has been upgraded.

SUN YE, Wenchang, Hainan province "Whenever a Long March 5 rocket gets ready at the Wenchang Launch Center, it almost always means something major is going to happen."

In 2020, it's a Long March 5 rocket that started the Chang'e 5 mission, China's first lunar sample-return mission. In 2020, it's a Long March 5 rocket that started China's first Mars probe mission, Tianwen-1.

Modified versions of the Long March 5 rocket, or the Long March 5B rockets, have been the heavy-lifters that, one by one, propelled all three modules of China Space Station to space. And now, for the Chang'e 6 mission – where the probe is to retrieve samples from the mysterious far side of the Moon – an even more powerful Long March 5 rocket is tasked.

LI PINGQI, China Aerospace Science and Technology Corporation "This Long March 5 rocket has a greater carrying capacity. It can haul a heavier probe. Compared to the Chang'e 5 mission, the weight of the probe this time is heavier by 100 kilograms. Going to a lunar transfer orbit with an increase of 100 kilograms is a considerable upgrade for our rocket."

Li said Chang'e 6 probe would be the heaviest probe ever for China's deep space missions. And for Chang'e 6, the rocket is also better when it comes to time management.

LI PINGQI, China Aerospace Science and Technology Corporation "For deep space exploration missions, the launch time window requirements are quite strict. So, it must be launched at a specific time so that the follow-up procedures, lunar orbiting and landing could take place. Therefore, in this mission, we adopted the 'narrow window, multiple trajectories' launch scheme. For the Chang'e 6 mission, the launch window has a width of 50 minutes each day for two consecutive days."

The rocket is also available for some last minute operational needs.

LI PINGQI, China Aerospace Science and Technology Corporation "We have added an operation port to our fairing this time. So, if we need to operate at the last moment, including when it's at the launch tower, we can open the relevant port to operate."

Compared to the Chang'e 5 mission rocket, this Long March 5 rocket catering to the Chang'e 6 mission also has its reliability index up from 0.86 to 0.93. SY, CGTN, Wenchang, Hainan Province.