2.6 Other Lunar Environments
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Fig. 2.16 The variation of elevation angle and azimuth angle of Sun in one lunar daytime
Fig. 2.17 The variation of elevation angle and azimuth angle of Sun in one Earth year
Similar to Earth, the elevation angle and the azimuth angle of Sun vary with the
different longitude and latitude of locations on the lunar surface. And the rotational
period of the Moon is about 28 times of that of the Earth. Therefore, the rate of
variation of solar angle on lunar surface is about 1/28 of that of the Earth. Figure 2.16
shows the variation of elevation angle and azimuth angle of Sun in one lunar daytime
regarding the local horizontal plane of the landing site of the Chang’E-3 probe.
Figure 2.17 is the variation of elevation angle and azimuth angle of Sun in one Earth
year (December of 2013–December of 2014) at local level.
2.7 Summary
The lunar environment faced by lunar soft-landing mission on lunar orbit or on
lunar surface is introduced in this chapter. Lunar natural environment including the
radiation environment, the thermal environment on lunar surface, the landform and
topography of lunar surface, the lunar soil and dust, the lunar gravitational field, the