Chang’e-6 Lunar Mission: A Historic Leap to the Far Side

Space exploration took a significant step forward in 2024 with China’s Chang’e-6 mission. While humans and robots have visited the Moon many times, almost every sample collected previously came from the side facing Earth. The Chang’e-6 mission successfully changed that paradigm by becoming the first endeavor in history to retrieve soil and rock samples from the mysterious far side of the Moon.

The Mission Profile and Timeline

The Chang’e-6 mission was a complex 53-day undertaking orchestrated by the China National Space Administration (CNSA). It launched on May 3, 2024, from the Wenchang Space Launch Center in Hainan province atop a massive Long March-5 Y8 rocket.

Unlike direct missions that fly straight to the surface, this mission required a sophisticated series of maneuvers. The spacecraft consisted of four distinct modules:

  • Orbiter: To stay in space and transport the return capsule.
  • Lander: To descend to the lunar surface.
  • Ascender: To launch the samples back up from the Moon.
  • Returner: To bring the samples safely through Earth’s atmosphere.

On June 2, 2024, the lander successfully touched down in the Apollo crater. This impact crater lies within the South Pole-Aitken (SPA) Basin, which is the largest, deepest, and oldest impact basin on the Moon. The choice of this location was deliberate. Scientists believe the SPA Basin holds debris from the lunar mantle ejected during a massive ancient impact, offering clues to the Moon’s early formation.

Why the Far Side is Different

To understand the importance of Chang’e-6, you have to understand the “Lunar Dichotomy.” The Moon is not symmetrical. The near side (the one we see) is covered in “maria,” which are large, dark plains of cooled lava. The far side is heavily cratered, possesses a thicker crust, and has very little ancient volcanic activity.

Previous samples from the US Apollo missions and the Soviet Luna missions, as well as China’s own Chang’e-5, all came from the near side. This created a scientific blind spot. We have built our theories of lunar evolution based on data from only one hemisphere.

By collecting samples from the far side, scientists hope to answer specific questions:

  • Why is the crust thicker on the far side?
  • When did the South Pole-Aitken basin form?
  • Does the soil contain materials from the deep lunar mantle?

The Collection Process

Once the lander settled in the Apollo crater, it had to work quickly. The probe used a drill to bore into the surface and a robotic arm to scoop up loose regolith (surface soil). The goal was to collect about 2 kilograms of material.

The process was highly automated. Because the far side of the Moon never faces Earth, direct radio communication is impossible. To solve this, China deployed the Queqiao-2 relay satellite in March 2024. This satellite orbits the Moon in a specific pattern that allows it to “see” both the lander on the far side and ground stations on Earth simultaneously, acting as a data bridge.

After gathering the samples, the ascender module blasted off from the lunar surface on June 4. In a feat of incredible precision, it rendezvoused and docked with the orbiter module circling the Moon. The samples were transferred to the return capsule, which then began the long journey back to Earth.

International Collaboration

While this was a Chinese mission, it carried significant international payloads, marking a new era of cooperation for the CNSA. The lander and orbiter hosted four scientific instruments from other nations:

  1. France (DORN): The Detection of Outgassing Randon instrument measured radon gas to study how the lunar atmosphere interacts with the regolith.
  2. Italy (INRRI): A passive laser retro-reflector used for laser ranging and positioning.
  3. ESA/Sweden (NILS): The Negative Ions at the Lunar Surface instrument, developed by the Swedish Institute of Space Physics with support from the European Space Agency, detected negative ions emitted from the surface.
  4. Pakistan (ICUBE-Q): A miniature satellite (CubeSat) that separated from the orbiter to take optical images of the moon and the mission.

Return and Results

The mission concluded successfully on June 25, 2024. The return capsule landed in the Siziwang Banner region of Inner Mongolia. Upon opening the canister in Beijing, scientists confirmed the mission had retrieved 1,935.3 grams (roughly 1.9 kg) of lunar material.

These samples are visually distinct from near-side samples. Initial visual inspections showed the soil appears looser and more distinct than the samples brought back by Chang’e-5 in 2020. Research teams are now analyzing the isotopes within these rocks to determine their exact age. If the samples are as old as expected (around 4 billion years), they could rewrite the timeline of the heavy meteorite bombardment that occurred in the early solar system.

Frequently Asked Questions

Is the far side of the Moon the same as the “dark side”? No. This is a common misconception. The “far side” is simply the side facing away from Earth. It gets just as much sunlight as the near side. When we see a “new moon” from Earth, the far side is fully illuminated by the sun.

What happens to the samples now? The samples are stored at the Chinese Academy of Sciences in Beijing. They will be distributed to research teams for chemical and geological analysis. Eventually, portions of the samples may be shared with international scientists, similar to how Apollo samples were distributed globally.

Will humans go to the far side of the Moon? Currently, most crewed programs (like NASA’s Artemis program and China’s future crewed missions) target the lunar South Pole rather than the specific far side regions visited by Chang’e-6. The South Pole is of high interest because deep craters there may contain frozen water ice.

How does this compare to the Apollo missions? The Apollo missions (1969-1972) brought back much more material (382 kg total) and involved human explorers. However, Chang’e-6 achieved something Apollo did not: accessing the geographically distinct terrain of the far side, which provides the missing half of the Moon’s geological history.