Published on : 26/06/2024
The Chang'e-6 lunar exploration mission has gone through 53 days since its launch, and at 14:07 on June 25, the returner of the Chang'e-6 probe touched down on Earth in Siziwang Banner of north China's Inner Mongolia Autonomous Region, bringing back the world's first samples collected from the moon's far side.
Chang'e-6｜Re-entered the atmosphere in a semi-ballistic skip manner
The Chang'e-6 returner adopted a "semi-ballistic skip return" method.
Specifically, the Chang'e-6 returner entered the earth's atmosphere for the first time over the Atlantic at a high speed close to the second cosmic velocity, at an altitude of about 120 kilometres from the ground, to implement the initial aerodynamic deceleration.
After descending to the predetermined altitude, the returner jumped out of the atmosphere over the Indian Ocean and began to glide down after reaching the highest point. Then, the returner re-entered the atmosphere and implemented a second aerodynamic deceleration.
According to researchers, the Chang'e-6 returner flew from the moon to the earth at a very fast speed and had to decelerate during the return process.
This design aims to use the resistance and heat generated by friction with the atmosphere over several thousand kilometres to quickly deplete the returner's energy, so that its speed is reduced to below the first cosmic speed when it passes through the atmosphere again, lacking the conditions for circumventing the earth and entering the atmosphere for the second time.
In addition to slowing down, it also had to overcome the impact of high temperatures.
To ensure that the returner is both heat resistant and erosion resistant, the Chang'e-6 returner borrowed from the experience of Chang'e-5, and "wore" a tailor-made "intimate heat-resistant clothing" according to the specific requirements and indexes of burn resistance and insulation of different parts, and returned to Earth safely and smoothly.
At an altitude of about 10 kilometres from the ground, the Chang'e-6 returner opened the parachute to complete the final deceleration and maintain a stable attitude, and then accurately landed in the designated area.
Chang'e-6｜Transported to Beijing for further studies
Chang'e-6 returner will be transported to Beijing for opening and removal of the sample container and payloads.
The National Space Administration will hold a ceremony at an appropriate time, officially hand over the lunar samples to the ground application system, and subsequently carry out sample storage, analysis, and research related work.
After completing the Chang'e-6 mission, the Queqiao-2 relay satellite will conduct scientific exploration missions at an appropriate time, and its extreme ultraviolet camera, array neutral atom imaging instrument, and Earth-Moon very long baseline interferometry measurement test system, will collect scientific data from the moon and deep space.
Read more: Chang'e-6 mission: Humans will return soil from the far side of the moon for the first time
