Step 1. Making the model
The first part of the activity involves building the model:
1- Cover the wood board representing the ground with black sandpaper.
2- Paint the wood board representing the sky in blue.
3- Make tiny holes on the board representing the stars (they can be in constellation forms)
4- Put the small led lamps (Christmas Tree Lights) into the holes to represent the stars.
5- Put a removable reflective paper on the ground when needed. This model takes into consideration the nature of the ground and its reflectivity (albedo) in order to show its effect on the diffusion of light where it’s not needed.
Step 2. Observations
Once the model is ready, students are encourage to observe the model under different lighting configurations:
1- Observing the model with no lighting added (see Image 1- Absence of Light pollution)
2- Observing the model when bad lighting is added (see Image 2 - Light pollution)
3- Observing the model when better lighting is added (see Image 3 - Minimize light pollution effects)
4- Observing the model with the reflective floor (see Image 4 - effect of reflective floors even with good lighting)
Image 4 : absence of Light pollution
Image 5 : light pollution
Image 6 : minimization of light pollution effects
Image 7 : effect of reflective floors even with good lighting
Step 3. Discuss the results
Observing different lighting setups, the students can learn how to use outdoor lighting responsibly by only using it where it’s needed and in the amount required (images 4,5,6). This model also takes into consideration the nature of the ground and its reflectivity (albedo) in order to show its effect on the diffusion of light where it’s not needed (image 7).
In the following discussion, it is very important to raise awareness about the negative impact light pollution can have on the night sky and on biodiversity.
You can also discuss with the students different kinds of "good and bad" light shown in Image 8.
Image 8 : examples of acceptable and unacceptable lighting
Step 4. Minimize light pollution in your school (optional)
If the activity is taking place in a school we can suggest that, afterwards, the students who worked on the activity take a tour of the school and give their opinion on whether the external lighting installed meets the requirements to minimize light pollution and if not to submit their suggestions to the management.