China’s twin-launch Chang’e 4 mission to the far side of the moon will place a pair of microsatellites in lunar orbit this spring “to test low-frequency radio astronomy and space-based interferometry.” The two satellites, unofficially called DSLWP-A1 and DSLWP-A2 (DSLWP = Discovering the Sky at Longest Wavelengths Pathfinder), could launch this spring. The pair represent the first phase of the Chang’e 4 mission, which involves placing a relay satellite in a halo orbit to facilitate communication with the Chang’e 4 lander and rover, which will be sent to the far side of the moon in December. Because the moon’s far side never faces Earth, the satellite is needed to serve as an Earth-moon relay. The Chang’e 4 mission will be the first-ever attempt at a soft-landing on the far side of the moon.
The two spacecraft also will carry Amateur Radio and educational payloads, but not a transponder. Developed by students at the Harbin Institute of Technology, the Amateur Radio payload on DSLWP-A1 will provide a telecommand uplink and a telemetry and digital image downlink. Radio amateurs will be able to transmit commands that allow them to send commands to take and download an image.