Influence of the layered Moon and Earth’s orientation on lunar rotation

Abstract

One of the most efficient ways to probe the lunar inner structure at present is through the study of its rotation. Range and range rate (Doppler) data between the Chang’E-3 lander and station on the Earth were collected from the beginning of the Chang’E-3 lunar mission in 2013. These observation data, taken together with the existing lunar laser ranging data, provide a new approach to extend research on the Earth-Moon system. The high precision of current observation data imposes exacting demands, making it necessary to include previously neglected factors. In this paper, motivated by progress of the Chinese lunar exploration project and to use its data in the near future, two lunar models: a one-layer model and a two-layer model with a fluid core, were applied to the rotational equations based on our implemented algorithm of the Moon’s motion. There was a difference of about 0.5″ in ϕ and ψ, but 0.2″ in θ between the two models. This result confirms that stratification of the inner structure of the Moon can be inferred from rotation data. We also added precise Earth rotation parameters in our model; the results show that this factor is negligible at present, due to the limited precision of the existing data. These results will help us understand the rotational process clearly and build a more realistic Earth-Moon model when we combine Lunar Laser Ranging data with high precision radio data to fit lunar motion in the near future.

Soft-Landing Dynamic Analysis of a Manned Lunar Lander Em-Ploying Energy Absorption Materials of Carbon Nanotube Buckypaper

“…The most eye-catching one was the “Apollo 11” lunar manned probe, which succeeded in manned soft landing on the moon for the first time [ 1 , 2 , 3 , 4 ]. After years of silence, China’s “Chang’e Project” also successfully realized the soft landing of unmanned lunar landers on the moon three times from 2014 to 2020 [ 5 , 6 , 7 ]. Soft landing means that the maximum center-of-mass acceleration of the lander is limited within several g to a dozen g during the whole landing process.…”