Question

Why there is no rain on moon?

Answer 1

For there to be any sort of rain over a planet you need two things:

-An atmosphere.

-Some component of that atmosphere that remains suspended above ground most of the time, but is able to condense and “precipitate” out of the air and fall to the ground in liquid form.

On Earth, that’s water. Or, more precisely, water vapor.

The Moon doesn’t have an atmosphere (okay, so it totally does, but it’s so thin as to be almost non-existent. Think “vacuum”. The pressure and density on the moon’s surface and actual outer space are pretty much the same.)

On other worlds (and their satellites), you can have it rain carbon bits, boiling sulfuric acid, liquefied methane, liquefied helium, or what have you.

Answer 2

atmosphere is not present on moon