Chang’e 6 Brings Back First Samples From the Lunar Far Side

On June 25, 2024, at 06:07 UTC, the return capsule carrying lunar samples from China’s Chang’e 6 mission successfully landed in Siziwang Banner, Inner Mongolia. This marks the successful conclusion of the sixth lunar exploration mission after 53 days.

Chang'e 6 return capsule with lunar samples. Credits: Jin Liwang — *Chang’e 6 return capsule with lunar samples. Credits: Jin Liwang*

Chang’e 6 mission achievements

The Chang’e 6 mission marks a historic milestone for lunar exploration. It is, in fact, the first mission to collect and return samples from the far side of the Moon to Earth. The return capsule contains about 2 kg of lunar material collected from the Apollo crater in the South Pole-Aitken (SPA) basin, a geological formation of crucial scientific interest.

Illustration of the Chang'e 6 on the lunar surface. Credits: CNSA — *Illustration of the Chang’e 6 on the lunar surface. Credits: CNSA*

These samples, extracted both from the surface and subsurface, could provide new insights into the Moon’s formation and evolution, particularly regarding the differences between the near side and the far side. The analysis of this material could help explain the Moon’s geological history and the reasons behind the significant differences between the two hemispheres of the satellite.

The mission timeline

The Chang’e 6 mission went through several critical phases. On June 3, at 23:38 UTC, the ascent module made the first historic takeoff from the far side of the Moon, entering a predetermined circumlunar orbit.

At 06:48 UTC, on June 6, the ascent module successfully rendezvoused and docked with the orbiter/returner in lunar orbit, safely transferring the sample container to the returner at 07:24 UTC. On June 21, the service module likely fired its engines to begin the return journey to Earth.

Illustration of the capsule reentry scheme with the lunar samples collected by the Chang'e 6 mission. Credits: Deep Space Exploration Jump Re-entry Return Mission Design — *Illustration of the capsule reentry scheme with the lunar samples collected by the Chang’e 6 mission. Credits: Deep Space Exploration Jump Re-entry Return Mission Design*

The final phase began on June 25, when the re-entry capsule, weighing about 300 kg, separated from the service module approximately 5,000 km from Earth. It then performed a semi-ballistic skip re-entry into the atmosphere over the Atlantic Ocean at 05:41 UTC to decelerate, entering at the second cosmic velocity of 11.2 kilometers per second. This maneuver preceded the final landing at the preselected site in Siziwang Banner, Inner Mongolia. Similar to Chang’e-5, the Chang’e-6 return capsule separated from the orbital module at about 5,000 kilometers from Earth.

While the return module re-entered on its own, the propulsion module fired its engines at perigee to avoid re-entry. The “Flying to the Moon” video documents the return and recovery process, drawing parallels with the Chang’e-5 mission.

Next steps in lunar exploration

The lunar samples collected by Chang’e 6 will now be distributed among various Chinese and international laboratories for a series of in-depth tests and research. These studies will cover different scientific fields and could provide new perspectives on lunar geology and evolution.

*Extraction of lunar samples from the capsule. Credits: Jin Liwang*

A key element in Chang’e 6’s success was the flawless operation of the Queqiao relay satellites, which ensured constant communication with the far side of the Moon, demonstrating their reliability for future missions. Furthermore, Chang’e 6 has provided rich visual documentation of its endeavor, releasing numerous extraordinary images and videos that have captured the attention of audiences worldwide.

The success of this mission paves the way for the next phase of Chinese lunar exploration, with Chang’e 7 already scheduled for the coming years.