China's Lunar Exploration Program today announced plans to land its Chang'e-4 spacecreaft on the far side of the moon, which has never before been explored, only photographed.
"We probably will choose a site on which it is more difficult to land and more technically challenging... Our next move will probably see some spacecraft land on the far side of the moon," said Wu Weiren, the agency's chief engineer, in an interview with China's state-run news service CCTV.
The far side of the moon -- also known as the dark side -- is never visible from Earth due to a phenomenon known as "tidal locking": tidal forces on Earth have slowed the moon's rotation to match the speed of its orbit. Thus, the "far side" is always facing away from Earth. It was first seen in 1959, when photographs taken by the Soviet lunar probe Luna 3 depicted hundreds of features of the lunar landscape.
China has already launched three lunar missions, two lunar orbiters and a lunar rover. In 2013, its Yutu rover was the first spacecraft to soft-land on the Moon since 1976; China is only the third nation to land on the surface of the moon.