Chang'e-4 has played its part in these plans by proving out new and improved precision landing technology that facilitated a safe descent and landing in challenging lunar terrain (make sure you check out the footage if you haven't already).

While this is all rather vague, further details of the new Chang'e mission concepts have been made available in conference papers from top lunar scientists. At a June conference in Macau, China last year, Zou Yongliao of the General Office of the Lunar and Deep Space Exploration under the Chinese Academy of Sciences gave a glimpse of the early plans for Chang'e-7. The mission is to consist of five spacecraft: an orbiter, relay satellite (whether this will be Qeqiao or a new spacecraft is not stated), lander, rover and 'fly-by robot.' The rover would analyze volatiles and the fly-by robot would be equipped with a water molecule and hydrogen isotope analyzer for in-situ detection of water ice in permanently shadowed areas.

Another paper, presented at LPSC 2018 (PDF) by Zou and others, also states lunar in-situ resource utilization and bio-scientific experiments as main scientific goals for the extended missions, along with an Earth-Moon Very Long Baseline Interferometry (VLBI) experiment involving the relay satellite. Chang'e-8, it says, could focus on in-situ rare-gas extraction and 3D-printing tests. Ecosystem experiments could also be carried out with a view to providing insight into systems to assist potential human lunar missions in the 2030s and even crewed lunar base concepts.

Who will be involved?

The press conference underlined that China is looking for partners for its lunar projects, and cited the coordination of images, data and landing information between teams involved in NASA's Lunar Reconnaissance Orbiter and China's Chang'e-4 mission.

CNSA Secretary-General Li Guoping also stated that China would be cooperating with Russia in its Luna 26 (Luna-Resurs-Orbiter) mission and on a Chinese lunar south pole landing, as well as research on lunar water ice and ultrasonic drilling. Beyond this, Chang'e-8 could involve input from ESA and others.

"We hope that Chang'e-8 will help test some technologies and do some exploring for the building of a joint lunar base shared by multiple countries," Wu Yanhua said, citing lunar 3D printing, which ESA is already researching.

When will all this happen?

Various timelines for the missions have been offered, none of which are official. One of the latest has Chang'e-7 launching in 2023 (as early as 2021 in others), followed perhaps a touch confusingly by Chang'e-6 in 2024, and Chang'e-8 in 2027. Another, presented (PDF) at the Sixty-first session of the Committee on the Peaceful Uses of Outer Space in June last year, has Chang'e-6 launching as soon as 2020, and Chang'e-7 and 8 in 2023 and 2026 respectively.