A released photo shows part of the moon with the earth as background. China and Saudi Arabia on June 14, 2018 jointly unveiled three lunar images acquired through cooperation on the relay satellite mission for Chang'e-4 lunar probe. An optical camera, developed by the King Abdulaziz City for Science and Technology of Saudi Arabia, was installed on a micro satellite, named Longjiang-2. The micro satellite is orbiting around the Moon. The camera, which began to work on May 28, has conducted observations of the Moon and acquired a series of clear lunar images and data. (Xinhua)