Chang’e 6 Chinese Lunar Mission Lands on the Far Side of the Moon

The Chinese lunar mission Chang’e 6 successfully landed on the far side of the Moon at 22:23 UTC on June 1. The lander descended into the South Pole-Aitken Basin, aided by communication with the Queqiao-2 lunar relay satellite.

Following the landing, the probe commenced drilling operations to collect samples for return to Earth. This mission marks a historic milestone as the second successful landing on the Moon’s far side and the first mission to retrieve samples from this region.

The Chinese lunar exploration program

Chang’e 6 is part of China’s Chang’e Lunar Exploration Program (CLEP), a long-term initiative aimed at fully exploring the Moon and establishing a permanent lunar base by 2030. The CLEP program is structured into four phases:

The first phase, from 2007 to 2013, involved sending lunar orbiters to map and select landing sites. The second phase, spanning from 2013 to 2020, focused on sending lunar landers and rovers to explore the lunar surface. The third phase, which runs from 2020 to 2030, is dedicated to developing technologies for lunar sample return and constructing lunar infrastructure. The final phase, beginning in 2030, aims to establish a permanent lunar base and send human missions to the Moon.

Overview of Chang’e 6 Mission

Chang’e 6, the sixth mission in this program, launched in May 2024 from the Wenchang Space Launch Center in southern China’s Hainan Province. The mission’s primary objective is to collect and return samples from the Moon’s far side.

This mission consists of an orbiter, a lander, an ascender, and a re-entry capsule, all designed by the China Academy of Space Technology. Upon reaching lunar orbit, the probe’s components separate, with the lander and ascender descending to the surface while the orbiter and re-entry capsule remain in orbit. After landing, the lander uses a drill and mechanical arm to gather surface and underground samples.

Chang’e-6 probe carries 4 international scientific payloads, including 3 installed on the #lander:
The #DORN (Detection of Outgassing Radon) from @CNES; #NILS (The Negative Ions at the Lunar Surface) from @esa; and a retroreflector from #Italy. pic.twitter.com/97CwAAIpmD

— Wu Lei (@wulei2020) June 2, 2024

This mission also includes multiple international scientific payloads, making it a collaborative effort. The collected samples will be transferred to the ascender, which will then dock with the orbit-return combination. The returner will re-enter Earth’s atmosphere and land in Siziwangqi, Inner Mongolia, completing the historic mission.

The landing of Chang’e 6

The Chang’e 6 mission achieved a significant milestone on June 2, 2024, when the lander-ascender combination successfully touched down on the far side of the Moon at 6:23 a.m. Beijing Time. Supported by the Queqiao-2 relay satellite, the landing occurred in the South Pole-Aitken (SPA) Basin, marking the first time samples will be collected from this rarely explored terrain.

After its launch on May 3, 2024, the mission underwent several critical stages, including Earth-Moon transfer, near-Moon braking, lunar orbiting, and the final landing descent. On May 30, the lander-ascender combination separated from the orbiter-returner combination to begin its descent.

The powered descent started at 6:09 a.m., with the main engine igniting to adjust the spacecraft’s attitude as it approached the lunar surface. An autonomous visual obstacle avoidance system was employed to detect and avoid hazards, with a visible light camera selecting a safe landing area.

The lander then hovered approximately 100 meters above the surface to use a laser 3D scanner for final obstacle detection before a controlled vertical descent. The engine shut down just before touchdown, allowing the lander to fall freely onto the surface, cushioned by its landing system.

Equipped with advanced sensors, including microwave, laser, and optical imaging tools, the lander ensured a precise and safe landing. The rugged terrain of the far side of the Moon, particularly the SPA Basin, presented unique challenges, but the site was chosen for its relative flatness and scientific value.

Post-landing, the Chang’e 6 probe commenced its mission to collect lunar material. Utilizing a drill for subsurface extraction and a robotic arm for surface collection, the probe aims to complete this task within 14 hours due to the limited communication window.

The mission’s efficiency is enhanced by its autonomous capabilities, reducing the need for constant ground intervention and allowing for more streamlined operations. This breakthrough in intelligent and rapid sampling represents a significant advancement in lunar exploration technology.