Parameter optimization for Rayleigh–Mie lidar under different dust conditions for the landing area of Martian Tianwen-1

Abstract

Mars is the terrestrial planet in the solar system that is closest to the Earth. Studying the atmospheric parameters of Mars and studying the evolutionary history of the Martian environment on this basis is helpful for people to discover signs of extraterrestrial life and to study the trend of climate change on Earth. Mie–Rayleigh scattering lidar is an important technology for detecting parameters from the surface to the middle and upper atmosphere. Because of the different aerosol distributions, Mie scattering and Rayleigh scattering have their own optimal detection ranges. Given the long period and high cost of any deep space exploration program, it is important to conduct sufficient feasibility studies and parameter simulations before the payload is launched. In this study, a parameterized lidar mathematical model and Earth’s atmospheric mode are used to compare with the measured signals of ground-based Mie–Rayleigh scattering lidar, and the correctness of the lidar mathematical model is verified. Using the model, we select the landing area of Tianwen-1 and substitute it into the Martian atmospheric mode, and then the Mie–Rayleigh lidar backscattering signal and the key parameters of the lidar system are systematically analyzed under the conditions of a clean Martian atmosphere and a global sandstorm. In addition, the optimal detection altitude ranges of Mie scattering and Rayleigh scattering on Mars under different atmospheric conditions are obtained, which provides a reference for the practical design and development of the subsequent lidar system for the Martian atmospheric environment.

Keywords

• lidar
• martian atmospheric mode
• mie scattering
• rayleigh scattering