On March 4, the China National Space Administration (CNSA) publically released the first set of high-definition pictures - two black-and-white and one color - of Mars taken by Tianwen-1, China's unmanned Mars probe.  

Color picture of Mars' north pole taken by Tianwen-1 probe. [Photo provided by CNSA] 

The Mars probe carries two types of cameras. One is a mediate resolution camera (MRC) with a resolution of 100 meters in orbit at an altitude of 400 kilometers, and can be used to draw a global remote sensing image map of Mars, and assess the Martian topography and its changes. 

The others are high resolution cameras (HRC) with a resolution of 2 meters in orbit at an altitude of 400 km, and can carry out detailed observations of the topography and landforms of key areas on Mars. 

The Changchun Institute of Optics, Fine Mechanics and Physics and the Xi'an Institute of Optics and Precision Mechanics, two institutes under the Chinese Academy of Sciences (CAS), have made great contributions to the Mars photography. The HRC load was developed by the Changchun institute, while the Xi'an institute undertook the research and development of MRC's optical modules.  

Their achievements have previously been exhibited at the China Hi-Tech Fair (CHTF). 

The Changchun institute showcased its optical products, including the space optical remote sensors, ultra-large aperture optical materials, and the COMS image sensor, at the 17th CHTF, which took place in Shenzhen, Guangdong province from Nov 16 to 21, 2015. 

The Xi'an institute presented their scientific and technological achievements made during the 13th Five-Year Plan period (2016-20) at the 22nd CHTF, which was held in Shenzhen from Nov 11 to 15, 2020, exhibiting 15 products in six categories.