Largest sample returned from the Moon by an autonomous lander

The largest sample returned from the Moon by an uncrewed lander comprised 1,935.3 grams (4 lb 4.2 oz) of regolith, returned to Earth by Chang'e-6 on 25 June 2024. This uncrewed lander, operated by the China National Space Administration (CNSA), collected its samples from the Apollo Basin on the Moon's far side between 1 and 3 June 2024.

The Chang'e-6 lander was based on hardware originally built as the backup for the 2020 Chang'e-5 sample-return mission. As that was a success, the spare backup was repurposed for a secondary mission. The CNSA has placed a lander on the lunar far side before (2018's Chang'e-4), and many aspects of this mission's design were informed by that previous experience. The launch of the probe itself was preceded by the launch of a relay satellite called Queqiao-2 on 20 March 2024, which was to maintain a halo orbit around the lunar far side, enabling communication with the lander.

The mission launched on a Long March 5 heavy-lift rocket from the Wenchang Space Launch Site, located off China's southern coast on the island of Hainan. The Chang'e-6 spacecraft entered lunar orbit on 8 May and remained there for three weeks while mission controllers checked its systems.

The basic architecture of the Chang'e-6 (and Chang'e-5) mission was broadly similar to the crewed Apollo missions of the 1960s and 1970s. The spacecraft consisted of two main parts, a service module/orbiter and a lander/ascender. On 30 May, the lander section detached and began its descent to the surface, touching down in the approximately 4-billion-year-old impact crater known as the Apollo Basin on 1 June.

The Chang'e-6 lander was not designed for a long operational life. On landing it deployed a small rover to take pictures, set up a few static experimental payloads and began extracting soil samples with its robotic arm and drill. The samples were loaded into the payload capsule of the ascender module, which took off from the Moon's surface on 3 June, making the rendezvous with the service module in lunar orbit. The combined spacecraft returned to Earth, with the ascender detaching to return to Earth.

Scientists in China are currently studying the samples, and they are likely to be shared with international research teams within a few years of their return (as were the samples from Chang'e-5). It is hoped that the material extracted from the Apollo Basin – where a massive impact likely uncovered material from the Moon's interior – will shed some light on the Moon's ancient volcanoes and the reasons for the differences between the Moon's far side and near side.

Chang'e-6 claimed the record previously held by Chang'e-5, which returned 1,731 grams (3 lb 13 oz) to Earth on 16 December 2020. Prior to that, the record had been held by the Soviet Luna 24 mission, which brought back 170 grams (6 oz) of lunar soil, since 1976.