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I'm not buying this. The Moon is only a reflector, not a producer of light. The temperature of the light is that of the reflected source. Moonlight is sunlight, more or less. The fact that the moon reflects poorly is compensated by the size of the gathering lens or mirror.

Suppose we build a 100 foot mirror which reflects 10% of sunlight, such that the spectrum remains the same. We could still make a fire with the reflected light, if we just gather 10 times more of it with a larger lens. We could do this in the Arctic, with the mirror's temperature at below zero; the mirror's temperature is irrelevant.




What matters is that we have intensity with quadratic falloff. Light from the sun has quadratic falloff based on the distance from the sun and hence can't be bent to become more intense than at the suns surface. Similarly light from the moon has quadratic falloff based on the distance from the moon and hence can't be bent to become more intense than at the moons surface. If you put a mirror on the moon, then the light from it will have quadratic falloff from the reflected sun and not the moon, which is why it can be used to heat to sun level temperatures.


Yes, since the moon is a scattering reflector, in fact the inverse square dropoff of moonlight is based on the distance from the moon.

Note that the article claims that no matter how much moonlight we are able to gather (i.e. we are allowed to overcome the inverse square law however much we want) we cannot create a temperature that will ignite paper.




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