China is about to land on the far side of the moon, exploring a place that remains almost entirely unknown to us despite being so close by.
The mission will be a pioneering look at the far side of the moon – a region that is forever hidden from the Earth, since we see the same side all of the time. Even messages cannot be relayed easily from that distant area, and it has remained unexplored by any rover.
And the Chinese robot that will make its way to the surface is almost as mysterious as the world it has explored: China has revealed very little about the process of getting it there, and the exact time and location of the landing remains unknown. Its space agency is likely to announce both after it has successfully happened.
State media reports suggest the Chang'e-4 craft will drop onto the surface some time over the next day. Rumours suggest that is likely to happen early on Thursday morning UK time.
It has already dropped into the Moon's orbit and engineers will be preparing to land on its surface soon.
When it does arrive on the surface, it will be carrying a whole host of instruments ready to explore what it finds there. Those include tools that will help it understand the Moon's geology – as well as experiments that will test out the possibility of growing living things there.
China has successfully landed on the Moon before with a predecessor, the Chang'e-3. But this mission will be much more difficult, in large part because it will involve dropping around to an area entirely unexplored by robots like this before.
As well as being permanently hidden from view – meaning that the distant part of the moon is sometimes known as the "dark side" – the area is also thought to be quite different from the part of the Moon we see from the Earth. Scientists will explore those differences, and its unknown geology, with the new lander.
