China’s latest quest to sample and analyse material from the Moon is underway.
But unlike previous lunar voyages, the Chang’e 6 mission – launched at 5:27pm local time on Friday – aims to become just the second time a spacecraft has set down on the far side of the Moon, and the first to return soil samples from the region.
It’s the highly cratered side of the Moon that cannot be seen from our planet’s surface, thanks to the synchronous rotation that sees our lunar neighbour spin in lockstep with the Earth.
Chinese state news agency Xinhua reported the mission’s chief designer Wu Weiren as saying “we know very little about the moon’s far side. If the Chang’e-6 mission can achieve its goal, it will provide scientists with the first direct evidence to understand the environment and material composition of the far side of the moon, which is of great significance”.
Chang’e 6 is the latest phase of China’s ongoing lunar exploration efforts: the almost identical Chang’e 5 probe landed on the near side of the Moon in 2020 to collect lunar regolith (Moon soil) samples; Chang’e 4 was the first of any nation to touch down on the moon’s far side in 2019.
A mission to understand far side history
Across its 53-day mission, Chang’e 6 will land, collect and bring home about 2kg of regolith from the 2,600km wide South Pole-Aitken (SPA) basin, the site of an ancient impact with another space body.
That collision deformed this southern pocket of the Moon enough to cause a vertical differential of about 15km from the basin’s central depths to the ridge of peaks formed in the impact.
By landing the Chang’e 6 spacecraft inside this region, China – and a global network of collaborating scientists – hopes to learn how old the SPA is.
The lander will use drills and scoops to collect the regolith before ascending to an orbiting service module, where the material will be transferred to a re-entry stage for its return to Earth. Those samples will be shared among several space research agencies for analysis.
However other space agencies are cautious about China’s plans for lunar exploration. NASA Administrator Bill Nelson has repeatedly voiced his concerns that China may not play nicely when it comes to space claims, though the Outer Space Treaty explicitly states space bodies (and space itself) cannot be claimed by any nation.
Following the Chang’e 6 launch, Nelson told NPR the Moon’s south pole “ought to be for the international community, for scientific research”, and that it was “important [for the US] to get there first”.
