The Sun never rises above the lunar poles by more than 7°. This means that the astronauts will be in difficult lighting conditions. The Sun will blind their eyes, and where there is shade, it will be extremely deep.
The Sun at the lunar poles
Like the Earth, the Moon has its axis of rotation. However, unlike the Earth’s, its inclination relative to the perpendicular to the ecliptic plane is quite small. As a result, the Sun never rises above the poles of our satellite by more than 7°.
This is very good because in this way the Sun’s rays never reach the bottom of lunar craters. This means that water ice can be stored there, which would have to be sublimated elsewhere, that is, directly transformed from a solid to a gaseous state. And then that vapor would dissipate into space.
Due to the low angle of incidence of the rays on the lunar poles, there are water reserves there that can be used in the construction and operation of the base. But now experts have turned their attention to the other side of this situation.
Abnormal lighting conditions
The low angle of the Sun relative to the horizon means that even at noon it hangs above it. This could be compared to a long dawn that gradually turns into a sunset. However, our sunrises and sunsets are much softer due to the presence of the atmosphere, which greatly softens the rays.
There is no atmosphere on the Moon, which means that astronauts may face a situation where the bright Sun will shine directly into their eyes in a few years. At the same time, the low angle of incidence of the rays will mean that each rock will cast long and very deep shadows.
Human eyes are simply not adapted to such sudden changes in illumination. We need to use our eyesight and navigate well with its help in a variety of operations. From simple movement to the construction of building structures.
Right now, engineers are developing spacesuits for future missions. But so far, no one has thought about how to take into account the problem of illumination in their design. After all, during the Apollo missions, the modules landed much closer to the equator, where there was no such problem.
Now something needs to be done about it. Experts suggest starting with experiments to determine how such lighting conditions affect people’s ability to identify objects and perform other tasks. Based on these, develop recommendations for spacesuit manufacturers.
Provided by phys.org
