Chang'e 4 (Chinese: 嫦娥四号; pinyin: Cháng'é sìhào) will be a Chinese lunar exploration mission, incorporating a robotic lander and rover. Chang'e 4 will be China's second lunar lander and rover, and was built as a backup to Chang'e 3, as Chang'e 2 was to Chang'e 1. Following the successful landing of the Chang'e 3 mission, the configuration of Chang'e 4 will be adjusted to meet new scientific objectives. Like its predecessors, the spacecraft is named after the Chinese Moon goddess.
The mission was scheduled for launch in 2015 as part of the second phase of the Chinese Lunar Exploration Program but the adjusted design of the mission imposed delays. It will now be launched by the end of 2018. Since Chang'e 4 is re-purposed to land on the far side of the Moon, CNSA will first launch a communication relay satellite to Earth-Moon L2 point in June 2018 as a communication relay station to relay the signals between the lander/rover and the earth station. The adjusted aims will include piloting a program that uses private investment from individuals and enterprises for the first time, a move aimed at accelerating aerospace innovation, cutting production costs and promoting military-civilian relationships.
An engineer from Chinese Academy of Sciences said the mission's re-purposed objective would be to study geological conditions on the far side of the Moon. It will be the first ever landing on the lunar far side. The potential landing spots include the South Pole-Aitken Basin  (the vast basin in the southern hemisphere of the far side which extends from the South Pole to Aitken crater).