Tiandu 1, 2

Tiandu 1 and Tiandu 2 before separation []

Tiandu 1 and 2 are two Chinese lunar navigation and communications test satellites.

Tiandu-1 and 2 will perform navigation and communications technology verification experiments while flying in formation in lunar orbit. Satellite-to-ground laser ranging as well as intersatellite microwave ranging techniques will be tested.

The Tiandu satellites' mission is to inform the design of China's proposed Queqiao lunar navigation and communication array. Supporting services for lunar surface operations would be provided by such system. Line-of-sight communications limits affect robotic and crewed operations on the moon, especially at the lunar south pole, an area of great interest, or the lunar far side.

The 61 kilogram Tiandu-1 carries a Ka dual-band integrated communication payload, a laser retroreflector, a space router and other payloads. The 15 kilogram Tiandu-2 carries a communication payload and navigation devices.

The mission is to be launched together with Queqiao 2 in 2024 on a CZ-8 (1).