Designing and validation of asteroid medium angle camera (AMAC) of Tianwen-2

<p indent="0mm">Through a single launch, China’s Tianwen-2 asteroid exploration mission will accomplish close-range exploration, sampling, and return of the near-Earth asteroid 2016HO3. Subsequently, the probe will proceed to the main-belt comet 311P to conduct fly-around detection. The asteroid medium angle camera (AMAC) is one of the main scientific payloads carried on the Tianwen-2 probe. Its scientific exploration mission is to image asteroids and main-belt comets and obtain their characteristics such as size, shape, morphology, and rotation parameters. The AMAC adopts a lightweight and integrated design, mainly consisting of the optical, focal plane, camera-control, power, camera-support, thermal-control and reference modules. Radiometric, color, and geometric calibrations have been carried out to ensure that the camera can accurately and correctly acquire images of the asteroid surface. This paper introduces the detection mission, system composition, working principle, ground calibration tests and results of the AMAC, providing a reference for scientific data processing and applications.