China's unmanned spacecraft marks the second successful landing on the far side of the moon and is expected to be the first to bring samples from this unexplored lunar region to Earth.

China has successfully landed an unmanned spacecraft on the far side of the moon, and it is expected to bring back soil samples to Earth, marking the first attempt to retrieve soil samples from this region. The Chang’e-6 mission lander successfully touched down in the Apollo Basin, a crater about 500 kilometers in diameter located within the Aitken Basin, a massive crater over 2,000 kilometers wide. The crater is situated in the southern region of the far side of the moon, which never faces Earth. The lander is equipped with a scoop and a drill for sampling the soil, and the Chinese space agency hopes it will collect about two kilograms of soil and rocks.

The lander is expected to collect samples for about two days, after which a portion containing the sample container will launch from the surface and dock with an orbiter—another unmanned spacecraft waiting in lunar orbit. If successful, the samples will reach Earth in about three weeks.

China is the only country to have successfully landed spacecraft on the far side of the moon. The Chang’e-4 mission was the first to do so in 2019, and there have been no landings or attempts since then. Missions to the far side are particularly challenging, partly because direct radio communication with the area is impossible. Therefore, the Chinese spacecraft relies on the Queqiao-2 relay satellite, launched by China in March this year, to transmit information from the far side of the moon to Earth.

Successful landing. A video compiled from still images of the landing stages: 

Combining The Two Capabilities 

The Chang’e-6 mission was launched about a month ago, and after four days successfully entered lunar orbit. Since then, it has made several maneuvers to enter a closer orbit around the moon, and the autonomous landing was scheduled for lunar morning in the Apollo Basin, when lighting and visibility conditions are optimal.The mission also involves a small rover and collaborations with several countries, including scientific instruments from France and Sweden to study gas ions near the lunar surface, an Italian laser reflector for distance measurement, and a small Pakistani satellite placed into lunar orbit.

As noted, China is the only country to have achieved a spacecraft landing on the far side of the moon and the first since the Soviet Union in the 1970s to successfully conduct an unmanned sample collection mission from the moon, in 2020. The current mission integrates both capabilities, aiming to retrieve the first samples from the far side. Researchers anticipate that these samples will help us better understand the geological differences between the moon's two hemispheres and, consequently, shed light on the geological history of our celestial neighbor and its formation. The mission will also represent another step toward China’s plan to land humans on the moon and ultimately establish a manned lunar base.

In recent years, many countries have been active in lunar exploration. The United States intends to return humans to the moon under the Artemis program, aiming to establish a research station as a base and testing ground for manned missions to Mars. As part of this, NASA's CLPS program encourages private company missions to the moon. In February of this year, the first private company spacecraft, Intuitive Machines' "Odysseus" lander, successfully touched down. India achieved a significant milestone by becoming the first country to successfully land a spacecraft near the moon's south pole, a region of great interest partly because researchers believe there are frozen water deposits near the lunar surface in that region, marking it as a prime target for the planned manned station. Shortly before India’s success, Russia's attempt to land its own unmanned spacecraft there ended in failure. Earlier this year, Japan also successfully landed its own spacecraft on the moon, bringing the number of countries  with successful moon landings to five.

 

 

Translated with the assistance of ChatGTP. Revised, expanded and edited by the staff of the Davidson Institute of Science Education