Measurement of the temperature of the lunar surface

Light is only a manifestation of temperature. The colder the light source, the longer the radiation waves emit.
There are two sources of energy from the moon.
1. Reflection of the sun light. Most of the radiation energy is concentrated in the visible spectrum near cyan.
2. The moon itself. Because the temperature is very low, the energy is concentrated in the infrared region, the wavelength of 10 microns.

By using a filter, it is easy to separate two sources of radiation from each other and then measure them with a very sensitive thermoelectric pair. The temperature of the moon surface can be obtained by calculating the measured results.

In addition, it is concluded that the material of lunar soil has very small heat capacity and weak conductivity. This is exactly what happens when the powder is made of fine opaque particles in the vacuum tube.

Measurement of the temperature of the lunar surface