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Given the changes of large camera angles and lighting conditions，the traditional algorithm of images’ feature point extraction cannot robustly realize extraction and matching between series images in the process of optical navigation during landing of the Mars rover. A joint detection-description feature extraction method based on convolutional neural network（CNN） is proposed to solve this. First，the video of the simulated Mars rover landing process is obtained by Blender. Then，the sparse reconstruction method is used to deal these images and real images of Mars，and establish a training dataset. Second，a convolutional neural network is built to process images by combining the dual roles of feature descriptor. And feature detector，and more accurate matching results are obtained by improving the loss function. Experiments show that this method has better results in feature detection of the Martian surface with multiple viewing angles and changing lighting conditions，and achieves better performance than traditional methods in the matching stage. [ABSTRACT FROM AUTHOR]

Mars shares many similarities with Earth. The comparative study of the climate between the two planets is of great significance to understand the evolution of the Earth's atmosphere. On the other hand, Mars is a desert planet with plenty of dust particles both on the ground and in the atmosphere. The dust cycle including the dust storm is an extremely important component of the climate system to Mars. Based on previous researches on the Martian dust storms and atmospheric waves, we summarized the temporal and spatial scales and the seasonal evolution of Martian dust storms. We introduced the characteristics of the Martian atmospheric tides and planetary waves and their responses to dust storms. The dynamical effect of the atmospheric waves on the transport and evolution of dust storms and the spatial distribution of the airborne dust is also significant. More future studies are needed to understand the coupling process between dust storms and atmospheric waves.

Objectives: The Chinese Mars probe has been successfully launched and is currently orbiting Mars. This article analyzes several different satellite orbit characteristics in detail to find out the suitable orbits with stable operation characteristics. Methods: This paper uses the MAGREAS （Mars gravity recovery and analysis software/system） independently developed by Wuhan University to analyze the evolution of satellite orbits under different initial orbit heights, different initial orbital inclinations, different initial orbital eccentricities, and different orders of Martian gravitational field models. Then we make orbit predictions for the four situations.Results: The results show that satellite can run for nearly two years without any orbital adjustment. When the initial orbital inclination is 90°, it does not contribute to the running time of the satellite. In the calculation of orbital integration, the Martian gravity field model can be intercepted to 100 degrees without affecting the calculation accuracy.Conclusions: This paper has done a lot of orbit predictions based on different initial orbit elements, and analyzed the evolution characteristics of different satellite orbits. This research can provide a certain reference for China's Mars exploration project. [ABSTRACT FROM AUTHOR]