Establishing communications with the farside
The Moon’s rotation and orbital periods are similar, leaving one face toward Earth. Equipment on the farside cannot communicate directly with ground stations, so Chang’e-4 relied on the Queqiao relay satellite.
Launched in 2018, Queqiao operated near the Earth–Moon L2 region, able to communicate with Earth and the farside craft. It provided a route for images, data and commands around the lunar obstruction.
Descending into Von Kármán crater
Chang’e-4 made a soft landing inside Von Kármán crater on January 3, 2019. The crater lies within the South Pole–Aitken basin, offering terrain relevant to lunar impact history and interior materials.
During descent the engine slowed the craft as onboard systems assessed terrain and adjusted position. The descent camera recorded changing views as the lander approached touchdown.
The lander and Yutu-2 begin surface work
After landing, Yutu-2 drove onto the surface. The lander remained stationary while the rover examined nearby terrain. Cameras, spectroscopy and subsurface measurements returned observations of the farside environment.
Long lunar days and nights required planning for power, temperature control and dormancy. Queqiao continued relaying communications between surface equipment and Earth.
Reconstructing the descent from images
Liu and colleagues published a 2019 study combining descent and navigation images with terrain data to reconstruct the powered trajectory and locate the landing site. Queqiao had returned the image sequence.
The first farside soft landing preserved both its engineering path and its scientific setting: how the craft descended and what it found afterward. These records connect surface views, orbital terrain and rover routes.