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Science Challenge #25
How does the surface of the moon
affect the reflection of sunlight?

Part 1; A smooth surface

Assume the Apollo astronauts took light sensors to the moon (similar to the light meters that professional photographers use) to measure the intensity of the sunlight.

The sensor at location A is facing the sun, so it will receive 100% of the sunlight.
The sensors at locations B and C will measure reflected light.

If the moon was a smooth, polished sphere of granite, what percent of the reflected light would reach sensors B and C?

Assume the sun is at an angle of 30°, as shown in this diagram.
Assume sensors A and B are also 30°, but rotated as shown.
Sensor C is only a few degrees from horizontal, as an astronaut's eyes might be if were looking at the horizon.

Astronaut George Bush has his back to the sun in this drawing.
What percentage of the sunlight will enter his eyes?
Will so much sunlight enter his eyes that he is unable to see the stars in the sky?



 
 

Part 2; An uneven surface of crushed rocks

Sensor A is facing the sun, so it will receive 100% of the sunlight, just as in Part 1 of this Science Challenge.

What percent of the reflected light would reach sensors B and C?

The Astronaut has his back to the sun.

Is NASA correct that the reflected light is so intense that he cannot see the stars?

Would an astronaut on the moon be amazed at the brightness of the surface, or the darkness of the surface?

Can you figure out if NASA is lying to us?

Were the Apollo moon landings a fake?