At 10.26am Beijing time (2.26am GMT), the Chang’e-4 probe touched down in the South Pole-Aitken Basin, Chinese state media said. The unmanned craft is carrying instruments to analyse the unexplored region’s geology and conduct experiments. The Chang’e-4 probe has already sent back its first pictures from the surface.
This achievement is a major milestone in space exploration.
While there have been many Moon missions over recent years, they have all been to orbit, flyby or impact.
Previous Moon missions have landed on the Earth-facing side, but this is the first time any craft has landed on the unexplored and rugged far side.
The last time a crewed vessel landed on the Moon was Apollo 17 in 1972.
The first time we had a look at the far side of the Moon was in 1959, when it was photographed by the Soviet Luna 3 space probe.
What is the far side of the moon?
The far side of the Moon is the hemisphere of the Moon that always faces away from Earth.
The far side’s terrain is rugged with a multitude of impact craters.
It has one of the largest craters in the Solar System, the South Pole–Aitken basin, where Chang’e-4 landed.
The far side is also sometimes called the “dark side” of the Moon.
However, this only refers to the side of the moon being unseen on earth – it still receives sunlight.
Does the moon rotate?
Yes, the moon does indeed rotate.
But the reason we never see the far side of the moon is due to what scientists call “synchronous rotation.”
The moon orbits the Earth once every 27.322 days.
It also takes approximately 27 days for the moon to rotate once on its axis.
This isn’t a coincidence: Tidal forces from Earth have slowed down the Moon’s rotation to the point where the same side is always facing the Earth — a phenomenon called tidal locking.
As a result, the moon does not seem to be spinning but appears to observers from Earth to be keeping still.