The Chang'e 8 robotic probe, the third to be placed on the moon during China's next lunar exploration endeavor, is open to foreign science payloads, according to the China National Space Administration, according to China Daily.com.cn.

Wang Qiong, deputy head designer of the Chang'e 8 mission, said on Monday at the ongoing 74th International Astronautical Congress in Baku - capital of Azerbaijan - that there will be 200 kilograms of payload capacity for piggyback missions on the Chang'e 8 robotic spacecraft.

Each piggyback payload should not weigh over 100kg. Preference will be given to independently controllable devices, lunar-surface robots as well as equipment new to Chinese lunar missions, according to Wang Qiong.

He said lunar regions around Leibnitz Beta, Amundsen crater, Cabeus crater and the Shackleton-de Gerlache Connecting Ridge have been chosen as candidate landing sites.

The Chinese space administration has set a deadline of Dec 31 for letters of intent, with preliminary and final selections to be completed by April and September 2024 respectively.

According to Chinese mission planners, the Chang'e 8 probe will consist of a lander, rover and robot. The spacecraft is set to land on the moon's south pole around 2028 to make on-site investigations of the environment and mineral composition of the landing site, carry out observation of the Earth, and test technologies for in-situ resource utilization.

In space exploration, in-situ resource utilization is the practice of collection, processing, storing and using materials found or manufactured on other astronomical objects like our moon or Mars that replace materials that would otherwise be brought from Earth.

The utilization of local resources will be crucial in human activities on the moon in the future, according to Wu Weiren, an academician of the Chinese Academy of Engineering and a leading scientist at the space administration.

"If we wish to stay for a long time on the moon, we need to set up stations by utilizing the moon's own materials. Lunar soil will be our raw material and will be made into construction materials through 3D printing technology," he told China Daily in April.

Wu and other space officials have said that the Chang'e 8 will follow the Chang'e 7 mission in 2026, which will also target the lunar south pole. The two coming missions will lay the groundwork for the nation's International Lunar Research Station project, an ambitious venture led by China that aims to take shape in the 2030s.