Reflection of only visible (safe) light on moon/mars

In summary, engineers are proposing shelter designs using local materials to protect astronauts from radiation on manned missions to the moon and Mars. However, the inclusion of windows poses challenges as they are not as effective in blocking radiation and can affect crop yields. The question is whether silver mirrors could be used to reflect only visible light while allowing gamma and x-rays to pass through, but this may not work for alpha, beta, and neutron particles. Additionally, cosmic rays can come from all directions and slow neutrons may not be a major concern. It is possible to apply filters to glass on silver mirrors to block UV, but the filtered UV is converted to heat.
  • #1
I have seen many articles lately regarding planned manned missions to the moon and Mars but the question of radiation protection constantly comes up. Engineers keep proposing various shelter designs that use local materials (regolith) as a concrete base to absorb harmful radiation so that the astronauts are not fried.

The problem I see is that every design also includes windows to allow some light in. I know windows can be created with heavy metal impurities to help absorb some radiation but: it is not as effective as a solid wall would be, a window with impurities is not as strong as one without impurities, and the addition of impurities also blocks some visible light that might reduce crop yields in a greenhouse.

My question is that if the habitat was built so that no window faced the sun during any point of the day or year (moon or mars), could silver mirrors (or other types) be used to reflect only the visible (safe) light but allow gamma and xrays to pass through the mirror so that they are not reflected into the habitat?

I know this wouldn't do anything for the Alpha, Beta, and Neutron particles that might be traveling in an angle to pass through the windows, but my question is only about the gamma and xray radiation.
 
  • Like
Likes Dale
Science news on Phys.org
  • #2
Cosmic rays come from all directions, not just from the Sun. Conventional mirrors mainly reflect infrared, visible light and maybe UV, but UV can be easily blocked by a window, so reflected light from a mirror is fine. A window that only points towards shielding outside plus a mirror in between would work. Maybe a two-mirror system. You would probably want to rotate the mirror to track the Sun.
 
  • #3
As I understand it, Cosmic rays are mostly Alpha, Beta, and Neutron particles. Would any of these be coming from the ground (below the horizon)? or would these particles only travel on a direct path from above the horizon (with the exception of minor reflections off of positive or negatively charged surfaces)?
 
  • #4
Not that much alpha, more protons but also heavier nuclei. Neutrons are not part of the primary cosmic rays but they can be produced in the atmosphere and on the ground. Photons (gamma) are relevant as well. Slow neutrons will come from all directions but they are probably not a big concern. The rest won't come from below.
 
  • #5
Since glass can have a filter applied to block UV, could you apply this directly to the glass on silver mirror?

If so, is that blocked UV light converted to thermal energy or reflected along the glass?
 
  • #6
Sam Phillips said:
Since glass can have a filter applied to block UV, could you apply this directly to the glass on silver mirror?
Probably, but every window that withstands the pressure difference will filter UV anyway (unless you take very special materials that don't).

It is converted to heat.
 

1. How does the reflection of visible light on the moon/mars affect their surface temperature?

The reflection of visible light on the moon/mars plays a crucial role in determining their surface temperature. Since visible light carries a significant amount of energy, the amount of light reflected back into space has a direct impact on the surface temperature. If more light is reflected, the surface will be cooler, and if less light is reflected, the surface will be warmer.

2. What factors influence the amount of visible light reflected on the moon/mars?

The amount of visible light reflected on the moon/mars is influenced by several factors such as the composition of the surface, the angle at which the light hits the surface, and the presence of reflective materials like ice or water. These factors can vary depending on the location and time on the moon/mars, resulting in different levels of light reflection.

3. Can the reflection of visible light on the moon/mars be measured?

Yes, the reflection of visible light on the moon/mars can be measured using instruments like spectrometers or radiometers. These devices can detect and measure the amount of light reflected at different wavelengths, providing valuable information about the composition and surface characteristics of the moon/mars.

4. Is the reflection of visible light on the moon/mars constant?

No, the reflection of visible light on the moon/mars is not constant. The amount of light reflected can vary depending on the factors mentioned above and can also change over time due to natural processes like erosion or human activities like spacecraft landings. Continuous monitoring is necessary to understand these changes and their impact on the moon/mars.

5. How does the reflection of visible light on the moon/mars impact the growth of plants?

The reflection of visible light on the moon/mars is essential for the growth of plants. Plants use visible light for photosynthesis, and the amount of light reflected affects the intensity and quality of light reaching the plants. Too little light reflected can hinder plant growth, while too much light reflected can cause damage. Understanding the reflection of visible light on the moon/mars is crucial for future plant growth experiments and colonization efforts.

Suggested for: Reflection of only visible (safe) light on moon/mars

Replies
64
Views
280
Replies
5
Views
186
Replies
2
Views
1K
Replies
172
Views
14K
Replies
3
Views
966
Replies
23
Views
2K
Replies
10
Views
668
Replies
4
Views
911
Back
Top