About the moon

Question

Why the Moon looks:
1. bigger
2. more yellow
when it is raising?

When it reaches the top of the sky, it becomes smaller and white in colour

Answer 1

This phenomenon is similar to the case of the sun during sun rise or sun set.

During moon rise, the light from the moon has to travel thicker atmosphere than when it is high up at the sky. Refraction effect is more prominent and the moon looks larger.

Since the moon itself is not a light source, it only reflects light from the sun and the temperature of the moon surface is much much lower than that of the sum. Because of the lower temperature, light reflected from the sun is shifted toward the red-yellow end of the visible spectrum. When light from the moon reaches the earth's atmsophere, Rayleigh scattering further deprives off the shorter wavelength light (i.e. those at the blue violet end of the spectrum). As a result, Only light of wavelength at the yellow end remains and thus the moon looks yellow.

Answer 2

或者可以參考 NASA 以下的網址
http://science.nasa.gov/headlines/y2002/24jun_moonillusion.htm