The Chang'e 4 mission's landing site was within a crater, known scientifically as the Aitken Basin.
The reason for choosing this location is related to the analyses by scientists from various countries on this southern polar region in the past, believing it to be extremely rich in mineral and ice content. The utilizable ice layers alone could weigh up to 270 billion tons, enough to manufacture an endless supply of fuel.
If a base for producing fuel could be constructed here, it could even provide fuel and supplies for Mars spacecraft.
Launching the same weight of fuel from Earth compared to launching from the Moon, even just to low Earth orbit, would be much easier due to the Moon's one-sixth gravity, saving a lot of resources.
The outside world only knew that Explorer 1 could travel by hopping, but the specific data and detection equipment it carried were unknown, let alone what Explorer 1 was there for.
