China has lost contact with one of the two test cubesats that were launched to the moon with their Queqiao Chang’e-4 communications satellite.
Though they continue to receive telemetry from one cubesat, without the second they will be unable to do the radio astronomy and interferometry experiments planned.
The interferometry experiments would have seen the observations made simultaneously by the DSLWP/Longjiang microsatellites to be combined. The test would be verification of technology for a constellation of small, low-frequency radio astronomy satellites that would emulate a telescope with a size equal to the maximum separation between the satellites.
The Chang’e-4 mission could however see some interferometry tests carried out, with Queqiao carrying the Netherlands-China Low-frequency Explorer (NCLE) astronomy instrument, and a Low Frequency Spectrometer (LFS) on the Chang’e-4 lander, which is expected to launch in November or December, following testing of Queqiao.
All is not lost. The cubesat that still functions has a camera, built in Saudi Arabia, and if it takes and successfully transmits any pictures this will be a cubesat landmark, the first interplanetary images ever taken by a cubesat.
Meanwhile, Queqiao Change’-4 is working as expected, laying the ground work for the launch of the Chang’e-4 lander later this year.